Process for the production of fluoropolymers

Abstract

Disclosed is a novel method for producing a fluorine-containing polymer. The present invention relates to a method for producing a fluorine-containing polymer, which comprises a step of polymerizing a fluorine-containing monomer in an aqueous medium in the presence of a polymer (1) containing a polymerization unit (1) based on a monomer represented by the following general formula (1). CX2=CY(-CZ2-O-Rf-A) (1).

Description

[0001] This application is a divisional application. The original application has the application number 201980015419.5, the application date is March 1, 2019, and the invention title is "Method for manufacturing fluoropolymers". Technical Field

[0002] This invention relates to a method for manufacturing fluoropolymers. Background Technology

[0003] In the case of manufacturing fluoropolymers via emulsion polymerization, specific methods for using fluoropolymers are known.

[0004] For example, Patent Document 1 discloses a method for manufacturing an aqueous dispersion containing rod-shaped microparticles of polytetrafluoroethylene with an average aspect ratio of 2 or more. The method is characterized in that tetrafluoroethylene is polymerized in the presence of a polymer composed of polymeric units shown in Formula 1, or a copolymer composed of polymeric units shown in Formula 1 and polymeric units shown in Formula 2 (wherein the polymeric units shown in Formula 1 account for 40 mol% or more of all polymeric units).

[0005] [Chemistry 1]

[0006]

[0007] -CF2CFX-···Form 2

[0008] In Equation 1, R f It is a perfluoroperfluoroalkylene group with 1 to 6 carbon atoms, M is an alkali metal ion or an ammonium ion, and X is a fluorine atom or a chlorine atom in Formula 2.

[0009] Existing technical documents

[0010] Patent documents

[0011] Patent Document 1: Japanese Patent Application Publication No. 11-181009 Summary of the Invention

[0012] The problem that the invention aims to solve

[0013] The purpose of this invention is to provide a novel method for manufacturing fluoropolymers.

[0014] Methods for solving problems

[0015] The present invention relates to a method for manufacturing a fluoropolymer, comprising the following steps: polymerizing a fluorinated monomer in an aqueous medium in the presence of a polymer (1) containing a polymerization unit (1) to obtain a fluoropolymer, wherein the polymerization unit (1) is based on a monomer represented by the following general formula (1).

[0016] CX2=CY(-CZ2-O-Rf-A) (1)

[0017] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0018] In the above general formula (1), at least one of X is preferably -H. In addition, in general formula (1), it is also preferred that both X are -H.

[0019] In the above general formula (1), Rf is preferably a fluorinated alkylene group with 1 to 10 carbon atoms or a fluorinated alkylene group with 2 to 12 carbon atoms having an ether bond.

[0020] The above-mentioned polymerization unit (1) is preferably a polymerization unit (1A) based on the monomer shown in the following general formula (1A).

[0021] CH2=CF(-CF2-O-Rf-A)(1A)

[0022] (In the formula, Rf and A are the same as above.)

[0023] In addition, the above-mentioned polymer unit (1) is preferably a polymer unit (1a) based on the fluoroallyl ether compound shown in the following general formula (1a).

[0024] CX2=CFCF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-A(1a)

[0025] (In the formula, each X is the same, representing F or H. n5 represents 0 or an integer from 1 to 10, and A is defined as above.)

[0026] In the above formula, A is preferably -COOM. Additionally, in the above formula, M is preferably -H, -Na, -K, -Li, or -NH4.

[0027] The content of polymeric unit (1) in the above polymer (1) is preferably 90 mol% or more relative to all polymeric units.

[0028] The number-average molecular weight of the polymer (1) is preferably 1.0 × 10⁻⁶. 4The above, and more preferably 3.0×10 4 above.

[0029] The fluoropolymer mentioned above is preferably polytetrafluoroethylene (PTFE). Furthermore, the PTFE mentioned above is preferably modified PTFE.

[0030] In addition, the present invention also relates to a method for manufacturing a stretched body, characterized in that it includes a step of stretching polytetrafluoroethylene obtained by the above manufacturing method.

[0031] Furthermore, the present invention also relates to a composition characterized in that it contains a fluoropolymer and a polymer (1) comprising a polymeric unit (1) based on a monomer represented by the following general formula (1).

[0032] CX2=CY(-CZ2-O-Rf-A) (1)

[0033] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0034] The above-mentioned polymerization unit (1) is preferably a polymerization unit (1A) based on the monomer shown in the following general formula (1A).

[0035] CH2=CF(-CF2-O-Rf-A)(1A)

[0036] (In the formula, Rf and A are the same as above.)

[0037] In the composition of the present invention, the content of the above polymer (1) is preferably 0.0001% by mass or more and 20% by mass or less relative to the fluoropolymer.

[0038] The fluoropolymer mentioned above is preferably polytetrafluoroethylene.

[0039] The polytetrafluoroethylene mentioned above is preferably modified polytetrafluoroethylene.

[0040] The composition of the present invention is preferably stretchable.

[0041] The fracture strength of the composition of the present invention is preferably 10.0 N or more.

[0042] The compositions of the present invention preferably do not contain fluorinated surfactants.

[0043] The composition of the present invention is preferably a powder.

[0044] The effects of the invention

[0045] The manufacturing method of the present invention is a novel method for manufacturing fluoropolymers. Detailed Implementation

[0046] Before describing the invention in detail, some terms used in this specification are defined or explained.

[0047] In this specification, fluoropolymer refers to partially crystalline fluoropolymers, also known as fluoroplastics. Fluoropolymers have a melting point, are thermoplastic, and can be melt-processed or non-melt-processed.

[0048] In this specification, melt processability refers to the ability to melt and process the polymer using existing processing equipment such as extruders and injection molding machines. Therefore, the melt flow rate of fluoropolymers with melt processability, as determined by the methods described later, is typically 0.01 to 500 g / 10 min.

[0049] In this specification, fluororubber refers to amorphous fluoropolymers. "Amorphous" means that the melting peak (ΔH) observed in differential scanning calorimetry (DSC) (heating rate 10°C / min) or differential thermal analysis (DTA) (heating rate 10°C / min) of the fluoropolymer is below 4.5 J / g. Fluororubber exhibits elastomeric properties through crosslinking. Elastomeric properties refer to the following characteristics: the polymer can be stretched and retains its original length when the force required for stretching is no longer applied.

[0050] In this specification, partially fluorinated rubber refers to a fluorinated polymer containing less than 90 mol% of fluorinated monomer units and perfluorinated monomer units relative to all polymer units. It is a fluorinated polymer with a glass transition temperature below 20°C and a melting peak (ΔH) size below 4.5 J / g.

[0051] In this specification, perfluorinated rubber refers to a fluoropolymer in which the content of perfluorinated monomer units relative to all polymer units is 90 mol% or more. It is a fluoropolymer with a glass transition temperature below 20°C and a melting peak (ΔH) value below 4.5 J / g, and further, a polymer containing fluorine atoms at a concentration of 71% by mass or more. In this specification, the concentration of fluorine atoms in a fluoropolymer is determined by calculating the concentration (by mass%) of fluorine atoms in the fluoropolymer based on the types and contents of each monomer constituting the fluoropolymer.

[0052] In this specification, a perfluorinated monomer refers to a monomer whose molecule does not contain carbon-hydrogen bonds. The aforementioned perfluorinated monomer may also be a monomer in which several fluorine atoms bonded to carbon atoms are replaced by chlorine atoms, in addition to carbon and fluorine atoms; or it may be a monomer in which nitrogen, oxygen, sulfur, phosphorus, boron, or silicon atoms are present in addition to carbon atoms. Preferably, the perfluorinated monomer in which all hydrogen atoms are replaced by fluorine atoms is a preferred embodiment. The aforementioned perfluorinated monomers do not contain monomers that provide crosslinking sites.

[0053] The monomer that provides the crosslinking site refers to a monomer with a crosslinking group (vulcanization point monomer), which provides the crosslinking site to the fluoropolymer for crosslinking by a curing agent.

[0054] In this specification, polytetrafluoroethylene (PTFE) is preferably a fluoropolymer in which the content of tetrafluoroethylene relative to all polymer units is 99 mol% or more.

[0055] In this specification, fluoropolymers (excluding polytetrafluoroethylene) and fluororubbers are preferably fluoropolymers in which the content of tetrafluoroethylene relative to all polymer units is less than 99 mol%.

[0056] In this specification, the content of each monomer constituting the fluoropolymer can be calculated by appropriately combining NMR, FT-IR, elemental analysis, fluorescence X-ray analysis, and other known methods according to the type of monomer.

[0057] In this specification, "organic group" refers to a group containing one or more carbon atoms, or a group formed by removing one hydrogen atom from an organic compound.

[0058] Examples of this "organic group" include:

[0059] Alkyl groups that can have more than one substituent

[0060] Alkenes that can have more than one substituent

[0061] Alkyne groups can have more than one substituent.

[0062] Cycloalkyl groups can have more than one substituent.

[0063] Cycloalkenyl groups can have more than one substituent.

[0064] Cyclodiene groups can have more than one substituent.

[0065] Aryl groups can have more than one substituent.

[0066] Aryl groups can have more than one substituent.

[0067] Non-aromatic heterocyclic groups that can have more than one substituent

[0068] Heteroaryl groups that can have more than one substituent

[0069] cyano,

[0070] formyl group,

[0071] RaO-、

[0072] RaCO-、

[0073] RaSO2-、

[0074] RaCOO-、

[0075] RaNRaCO-、

[0076] RaCONRa-、

[0077] RaOCO-、

[0078] RaOSO2-, and,

[0079] RaNRbSO2-

[0080] (In these formulas, Ra is independently...)

[0081] Alkyl groups that can have more than one substituent

[0082] Alkenes that can have more than one substituent

[0083] Alkyne groups can have more than one substituent.

[0084] Cycloalkyl groups can have more than one substituent.

[0085] Cycloalkenyl groups can have more than one substituent.

[0086] Cyclodiene groups can have more than one substituent.

[0087] Aryl groups can have more than one substituent.

[0088] Aryl groups can have more than one substituent.

[0089] It can be a non-aromatic heterocyclic group with more than one substituent, or

[0090] Heteroaryl groups can have more than one substituent.

[0091] Rb is independently H or may be an alkyl group having more than one substituent.

[0092] As the aforementioned organic group, it is preferable to have an alkyl group having one or more substituents.

[0093] In addition, in this specification, "substituent" refers to a group that can be substituted. Examples of such "substituents" include: aliphatic groups, aromatic groups, heterocyclic groups, acyl groups, acyloxy groups, amide groups, aliphatic oxy groups, aromatic oxy groups, heterocyclic oxy groups, aliphatic oxycarbonyl groups, aromatic oxycarbonyl groups, heterocyclic oxycarbonyl groups, carbamoyl groups, aliphatic sulfonyl groups, aromatic sulfonyl groups, heterocyclic sulfonyl groups, aliphatic sulfonyloxy groups, aromatic sulfonyloxy groups, heterocyclic sulfonyloxy groups, amino sulfonyl groups, aliphatic sulfonamide groups, aromatic sulfonamide groups, heterocyclic sulfonamide groups, amino groups, and aliphatic groups. Aliphatic amino, aromatic amino, heterocyclic amino, aliphatic oxycarbonyl amino, aromatic oxycarbonyl amino, heterocyclic oxycarbonyl amino, aliphatic sulfinyl, aromatic sulfinyl, aliphatic thio, aromatic thio, hydroxyl, cyano, sulfonyl, carboxyl, aliphatic oxyamino, aromatic oxyamino, carbamoylamino, aminosulfonylamino, halogen atom, aminosulfonylcarbamoyl, carbamoylaminosulfonyl, dialiphatic oxyphosphine, and diaromatic oxyphosphine.

[0094] The aforementioned aliphatic groups can be saturated or unsaturated. Furthermore, they may include hydroxyl, aliphatic oxygen, carbamoyl, aliphatic oxygen carbonyl, aliphatic thio, amino, aliphatic amino, amide, carbamoylamino, etc. Examples of aliphatic groups include alkyl groups with a total carbon number of 1 to 8, preferably 1 to 4, such as methyl, ethyl, vinyl, cyclohexyl, carbamoylmethyl, etc.

[0095] The aforementioned aromatic groups may include, for example, nitro, halogen, aliphatic oxygen, carbamoyl, aliphatic oxygen carbonyl, aliphatic thio, amino, aliphatic amino, amide, carbamoylamino, etc. Examples of such aromatic groups include aryl groups with 6 to 12 carbon atoms, preferably 6 to 10 total carbon atoms, such as phenyl, 4-nitrophenyl, 4-acetylaminophenyl, 4-methanesulfonylphenyl, etc.

[0096] The aforementioned heterocyclic group may have halogen atoms, hydroxyl groups, aliphatic oxygen groups, carbamoyl groups, aliphatic oxygen carbonyl groups, aliphatic thio groups, amino groups, aliphatic amino groups, amide groups, carbamoylamino groups, etc. Examples of such heterocyclic groups include 5- to 6-membered heterocycles with a total number of carbon atoms of 2 to 12, preferably 2 to 10, such as 2-tetrahydrofuranyl and 2-pyrimidinyl groups.

[0097] The aforementioned acyl group may be aliphatic carbonyl, aryl carbonyl, heterocyclic carbonyl, hydroxyl, halogen atom, aromatic group, aliphatic oxygen group, carbamoyl, aliphatic oxygen carbonyl, aliphatic thio, amino, aliphatic amino, amide, carbamoylamino, etc. Examples of such acyl groups include those with a total carbon number of 2 to 8, preferably 2 to 4, such as acetyl, propionyl, benzoyl, 3-pyridine carbonyl, etc.

[0098] The aforementioned amide groups may have aliphatic groups, aromatic groups, heterocyclic groups, etc., such as acetylamino, benzoylamino, 2-pyridine carbonylamino, propionylamino, etc. Examples of such amide groups include amide groups with a total carbon number of 2 to 12, preferably 2 to 8, and alkyl carbonylamino groups with a total carbon number of 2 to 8, such as acetylamino, benzoylamino, 2-pyridine carbonylamino, propionylamino, etc.

[0099] The aforementioned aliphatic oxycarbonyl group can be saturated or unsaturated. Furthermore, it can be hydroxyl, aliphatic oxy, carbamoyl, aliphatic oxycarbonyl, aliphatic thio, amino, aliphatic amino, amide, carbamoylamino, etc. Examples of aliphatic oxycarbonyl groups include alkoxycarbonyl groups with a total carbon number of 2 to 8, preferably 2 to 4, such as methoxycarbonyl, ethoxycarbonyl, tert-butoxycarbonyl, etc.

[0100] The aforementioned carbamoyl group may have an aliphatic group, an aromatic group, a heterocyclic group, etc. Examples of the aforementioned carbamoyl group include unsubstituted carbamoyl groups and alkyl carbamoyl groups with a total number of carbon atoms of 2 to 9. Preferred examples include unsubstituted carbamoyl groups, alkyl carbamoyl groups with a total number of carbon atoms of 2 to 5, such as N-methylcarbamoyl groups, N,N-dimethylcarbamoyl groups, and N-phenylcarbamoyl groups.

[0101] The aforementioned aliphatic sulfonyl groups can be saturated or unsaturated. Furthermore, they may contain hydroxyl groups, aromatic groups, aliphatic oxygen groups, carbamoyl groups, aliphatic oxygen carbonyl groups, aliphatic thio groups, amino groups, aliphatic amino groups, amide groups, carbamoylamino groups, etc. Examples of aliphatic sulfonyl groups include alkyl sulfonyl groups with a total carbon number of 1 to 6, preferably 1 to 4, such as methanesulfonyl groups.

[0102] The aforementioned aromatic sulfonyl groups may have hydroxyl, aliphatic, aliphatic oxygen, carbamoyl, aliphatic oxygen carbonyl, aliphatic thio, amino, aliphatic amino, amide, carbamoylamino, etc. Examples of such aromatic sulfonyl groups include arylsulfonyl groups with a total number of carbon atoms of 6 to 10, such as benzenesulfonyl groups.

[0103] The amino groups mentioned above can have aliphatic groups, aromatic groups, heterocyclic groups, etc.

[0104] The aforementioned acylamino group may be, for example, acetylamino, benzoylamino, 2-pyridine carbonylamino, propionylamino, etc. Examples of such acylamino groups include those with a total carbon number of 2 to 12, preferably 2 to 8, and more preferably alkyl carbonylamino groups with a total carbon number of 2 to 8, such as acetylamino, benzoylamino, 2-pyridine carbonylamino, propionylamino, etc.

[0105] The aforementioned aliphatic sulfonamide group, aromatic sulfonamide group, and heterocyclic sulfonamide group can be, for example, methylsulfonamide group, benzenesulfonamide group, 2-pyridinesulfonamide group, etc.

[0106] The aforementioned aminosulfonyl group may have an aliphatic group, an aromatic group, a heterocyclic group, etc. Examples of the aforementioned aminosulfonyl group include aminosulfonyl, alkyl aminosulfonyl with 1 to 9 total carbon atoms, dialkyl aminosulfonyl with 2 to 10 total carbon atoms, aryl aminosulfonyl with 7 to 13 total carbon atoms, heterocyclic aminosulfonyl with 2 to 12 total carbon atoms, more preferably aminosulfonyl, alkyl aminosulfonyl with 1 to 7 total carbon atoms, dialkyl aminosulfonyl with 3 to 6 total carbon atoms, aryl aminosulfonyl with 6 to 11 total carbon atoms, heterocyclic aminosulfonyl with 2 to 10 total carbon atoms, such as aminosulfonyl, methyl aminosulfonyl, N,N-dimethylaminosulfonyl, phenyl aminosulfonyl, 4-pyridine aminosulfonyl, etc.

[0107] The aforementioned aliphatic oxygen groups can be saturated or unsaturated, and may include methoxy, ethoxy, isopropoxy, cyclohexyloxy, methoxyethoxy, etc. Examples of aliphatic oxygen groups include alkoxy groups with a total carbon number of 1 to 8, preferably 1 to 6, such as methoxy, ethoxy, isopropoxy, cyclohexyloxy, methoxyethoxy, etc.

[0108] The aforementioned aromatic amino groups and heterocyclic amino groups may have aliphatic groups, aliphatic oxygen groups, halogen atoms, carbamoyl groups, heterocyclic groups fused with the aryl group, and aliphatic oxygen carbonyl groups. Preferably, they may have aliphatic groups with a total number of carbon atoms of 1 to 4, aliphatic oxygen groups with a total number of carbon atoms of 1 to 4, halogen atoms, carbamoyl groups with a total number of carbon atoms of 1 to 4, nitro groups, and aliphatic oxygen carbonyl groups with a total number of carbon atoms of 2 to 4.

[0109] The aforementioned aliphatic thio groups can be saturated or unsaturated. In addition, examples include alkylthio groups with a total number of carbon atoms of 1 to 8, more preferably 1 to 6, such as methylthio, ethylthio, carbamoylmethylthio, tert-butylthio, etc.

[0110] The aforementioned carbamoylamino group may have an aliphatic group, an aryl group, a heterocyclic group, etc. Examples of the aforementioned carbamoylamino group include carbamoylamino, alkyl carbamoylamino with 2 to 9 total carbon atoms, dialkyl carbamoylamino with 3 to 10 total carbon atoms, aryl carbamoylamino with 7 to 13 total carbon atoms, and heterocyclic carbamoylamino with 3 to 12 total carbon atoms. Preferably, carbamoylamino, alkyl carbamoylamino with 2 to 7 total carbon atoms, dialkyl carbamoylamino with 3 to 6 total carbon atoms, aryl carbamoylamino with 7 to 11 total carbon atoms, and heterocyclic carbamoylamino with 3 to 10 total carbon atoms, such as carbamoylamino, methyl carbamoylamino, N,N-dimethyl carbamoylamino, phenyl carbamoylamino, 4-pyridine carbamoylamino, etc.

[0111] Furthermore, in this specification, the range represented by the endpoints includes all values ​​contained in that range (for example, 1 to 10 includes 1.4, 1.9, 2.33, 5.75, 9.98, etc.).

[0112] Furthermore, in this specification, the term "at least 1" includes all values ​​greater than 1 (e.g., at least 2, at least 4, at least 6, at least 8, at least 10, at least 25, at least 50, at least 100, etc.).

[0113] Next, the method for manufacturing the fluoropolymer of the present invention will be described in detail.

[0114] The present invention relates to a method for manufacturing a fluoropolymer, comprising the following steps: polymerizing a fluorinated monomer in an aqueous medium in the presence of a polymer (1) containing a polymerization unit (1) to obtain a fluoropolymer, wherein the polymerization unit (1) is based on a monomer represented by the following general formula (1).

[0115] CX2=CY(-CZ2-O-Rf-A) (1)

[0116] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0117] The manufacturing method of the present invention, by using the above-described polymer (1), enables the stable and efficient production of fluoropolymers. Furthermore, it allows for the production of high molecular weight fluoropolymers in high yields.

[0118] In the above general formula (1), X is -H or -F. X can be both -F or at least one -H. For example, one can be -F and the other can be -H, or both can be -H.

[0119] In the above general formula (1), Y is -H, -F, alkyl or fluorinated alkyl.

[0120] The alkyl group described above is an alkyl group that does not contain fluorine atoms and has 1 or more carbon atoms. Preferably, the alkyl group has 6 or fewer carbon atoms, more preferably 4 or fewer, and even more preferably 3 or fewer.

[0121] The aforementioned fluorinated alkyl group is an alkyl group containing at least one fluorine atom, and the number of carbon atoms is one or more. Preferably, the number of carbon atoms in the aforementioned fluorinated alkyl group is 6 or less, more preferably 4 or less, and even more preferably 3 or less.

[0122] As for Y, -H, -F or -CF3 are preferred, and -F is more preferred.

[0123] In the above general formula (1), Z may be the same or different, and may be -H, -F, alkyl or fluoroalkyl.

[0124] The alkyl group described above is an alkyl group that does not contain fluorine atoms and has 1 or more carbon atoms. Preferably, the alkyl group has 6 or fewer carbon atoms, more preferably 4 or fewer, and even more preferably 3 or fewer.

[0125] The aforementioned fluorinated alkyl group is an alkyl group containing at least one fluorine atom, and the number of carbon atoms is one or more. Preferably, the number of carbon atoms in the aforementioned fluorinated alkyl group is 6 or less, more preferably 4 or less, and even more preferably 3 or less.

[0126] As Z is mentioned above, -H, -F or -CF3 are preferred, and -F is more preferred.

[0127] In the above general formula (1), at least one of X, Y and Z contains a fluorine atom. For example, X can be -H, and Y and Z can be -F.

[0128] In the above general formula (1), Rf is a fluorinated alkylene group having 1 to 40 carbon atoms, or a fluorinated alkylene group having 2 to 100 carbon atoms with ether bonds. It should be noted that the above fluorinated alkylene group having 2 to 100 carbon atoms with ether bonds does not contain a structure with an oxygen atom at the end, but is an alkylene group containing ether bonds between carbon atoms.

[0129] The number of carbon atoms in the aforementioned fluorinated alkylene group is preferably 2 or more. Furthermore, it is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less. Examples of the aforementioned fluorinated alkylene group include -CF2-, -CH2CF2-, -CF2CF2-, -CF2CH2-, -CF2CF2CH2-, -CF(CF3)-, -CF(CF3)CF2-, and -CF(CF3)CH2-. The aforementioned fluorinated alkylene group is preferably a perfluoroalkylene group.

[0130] The number of carbon atoms in the aforementioned fluorinated alkylene group having an ether bond is preferably 3 or more. Furthermore, it is preferably 60 or less, more preferably 30 or less, and even more preferably 12 or less.

[0131] For example, the following formula is also preferred:

[0132] [Chemistry 2]

[0133]

[0134] (where Z) 1 For F or CF3; Z 2 and Z 3 H or F respectively; Z 4 Let H, F, or CF3 be the integers p1+q1+r1, 0 to 10; s1 be 0 or 1; t1 be 0 to 5, where Z is an integer. 3 and Z 4 When all are H, p1+q1+r1+s1 is not 0, as shown by the divalent group.

[0135] Specifically, examples of fluorinated alkylene groups with ether bonds include -CF(CF3)CF2-O-CF(CF3)- and -(CF(CF3)CF2-O). n -CF(CF3)- (where n is an integer from 1 to 10), -CF(CF3)CF2-O-CF(CF3)CH2-, -(CF(CF3)CF2-O) n -CF(CF3)CH2- (where n is an integer from 1 to 10), -CH2CF2CF2O-CH2CF2CH2-, -CF2CF2CF2O-CF2CF2-, -CF2CF2CF2O-CF2CF2CH2-, -CF2CF2O-CF2CF2-, -CF2CF2O-CF2CH2-, -CF2CF2O-CF2-, -CF2CF2O-CF2CH2-, -CF(CF3)CH2-, etc.

[0136] The fluorinated alkylene groups with ether bonds mentioned above are preferably perfluoroalkylene groups.

[0137] In the above general formula (1), A is -COOM, -SO3M or -OSO3M (M is -H, a metal atom, or -NR). 74. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is H or an organic group.

[0138] As R 7 H or C are preferred 1-10 Organic groups, more preferably H or C 1-4 The organic groups, preferably H or C, are preferred. 1-4 Alkyl groups.

[0139] Examples of metal atoms that can be used as the aforementioned metal atoms include alkali metals (Group 1) and alkaline earth metals (Group 2), with Na, K, or Li being preferred.

[0140] As for M above, -H, a metal atom, or -NR is preferred. 7 4. More preferably -H, alkali metal (Group 1), alkaline earth metal (Group 2) or -NR 7 4. Further preferred are -H, -Na, -K, -Li or -NH4, even more preferred are -Na, -K or -NH4, particularly preferred are -Na or -NH4, and most preferred are -NH4.

[0141] As for A above, -COOM or -SO3M is preferred, and -COOM is more preferred.

[0142] As a monomer represented by general formula (1), for example, the following formula (1a) can be exemplified:

[0143] CX2=CFCF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-A(1a)

[0144] (In the formula, each X is the same, representing F or H. n5 represents 0 or an integer from 1 to 10, and A is the same as defined above.) The polymer unit based on the fluoroallyl ether compound shown is the preferred material.

[0145] In formula (1a) above, from the perspective of obtaining PTFE particles with small primary particle size, n5 is preferably an integer from 0 to 5, more preferably 0, 1 or 2, and even more preferably 0 or 1. From the perspective of obtaining moderate water solubility and surface activity, A is preferably -COOM. From the perspective of being less likely to remain as an impurity and improving the heat resistance of the obtained molded article, M is preferably H or NH4.

[0146] The polymer (1) mentioned above can be a homopolymer of the fluoroallyl ether compound represented by general formula (1a), or a copolymer with other monomers.

[0147] The above-mentioned polymerization unit (1) is preferably a polymerization unit (1A) based on the monomer shown in the following general formula (1A).

[0148] CH2=CF(-CF2-O-Rf-A)(1A)

[0149] (In the formula, Rf and A are the same as above.)

[0150] The polymer (1) mentioned above can be a homopolymer of the monomers represented by general formula (1A) or a copolymer of other monomers.

[0151] As a monomer represented by formula (1A), specifically, the following formula can be cited.

[0152] [Chemistry 3]

[0153]

[0154] (where Z) 1 For F or CF3; Z 2 and Z 3 H or F respectively; Z 4 Let H, F, or CF3 be the integers p1+q1+r1 from 0 to 10; s1 be 0 or 1; t1 be an integer from 0 to 5, where Z 3 and Z 4 The monomers shown are those where p1+q1+r1+s1 are not 0 when all are H. More specifically, preferred examples include...

[0155] [Chemistry 4]

[0156]

[0157] CH2=CFCF2OCH2CF2-A, CH2=CFCF2O(CH2CF2CF2O)CH2CF2-A,

[0158] CH2=CFCF2OCH2CF2CH2-A,

[0159] CH2=CFCF2O(CH2CF2CF2O)CH2CF2CH2-A,

[0160] CH2=CFCF2OCF2CF2-A, CH2=CFCF2O(CF2CF2CF2O)CF2CF2-A,

[0161] CH2=CFCF2OCF2CF2CH2-A,

[0162] CH2=CFCF2O(CF2CF2CF2O)CF2CF2CH2-A,

[0163] CH2=CFCF2OCF2-A, CH2=CFCF2O(CF2CF2O)CF2-A,

[0164] CH2=CFCF2OCF2CH2-A,

[0165] CH2=CFCF2O(CF2CF2O)CF2CH2-A,

[0166] etc., among which the preferred option is

[0167] [Chemistry 5]

[0168]

[0169] As the monomer shown in the above general formula (1A), A in the preferred formula (1A) is -COOM, and is particularly preferably selected from at least one of the group consisting of CH2=CFCF2OCF(CF3)COOM and CH2=CFCF2OCF(CF3)CF2OCF(CF3)COOM (where M is the same as defined above), and more preferably CH2=CFCF2OCF(CF3)COOM.

[0170] In addition, as a monomer shown in general formula (1), monomers such as those shown in the following formula can also be cited.

[0171] CF2 = CFCF2-O-Rf-A

[0172] (In the formula, Rf and A are the same as above)

[0173] More specifically, examples can be given.

[0174] [Chemistry 6]

[0175] CF2 = CFCF2OCF2CF2CF2-A,

[0176]

[0177] CF2=CFCF2OCF2CF2CF2CH2-A,

[0178] wait.

[0179] The polymer (1) described above can be a homopolymer consisting only of the polymeric unit (1) described above, or it can be a copolymer comprising the polymeric unit (1) described above and polymeric units based on other monomers that can copolymerize with the monomers shown in general formula (1). From the perspective of solubility in the polymerization medium, a homopolymer consisting only of polymeric unit (1) is preferred.

[0180] As other monomers mentioned above, fluorinated olefinic monomers with 2 or 3 carbon atoms are preferred, such as CF2=CF2, CF2=CFCl, CH2=CF2, CFH=CH2, CFH=CF2, CF2=CFCF3, CH2=CFCF3, CH2=CHCF3, etc.

[0181] From the perspective of good copolymerization, at least one of the following groups is preferred: tetrafluoroethylene (CF2=CF2), trifluorochloroethylene (CF2=CFCl), and vinylidene fluoride (CH2=CF2).

[0182] In addition, as other monomers mentioned above, the following formula (n1-2) can be cited:

[0183] [Chemistry 7]

[0184]

[0185] (where X) 1 X 2 Same or different, indicated by H or F; X 3 For example, H, F, Cl, CH3 or CF3; X 4 X 5 If they are the same or different, the value is H or F; if a and c are the same or different, the value is 0 or 1. Rf 3 It is a monomer represented by a fluorinated alkyl group having 1 to 40 carbon atoms or a fluorinated alkyl group having ether bonds having 2 to 100 carbon atoms.

[0186] Specifically, a preferred example is CH2=CFCF2-O-Rf 3 CF2 = CF-O-Rf 3 CF2 = CFCF2-O-Rf 3 CF2 = CF - Rf 3 CH2=CH-Rf 3 CH2=CH-O-Rf 3 (where Rf) 3 (Same as the above formula (n1-2) etc.)

[0187] As for the other monomers mentioned above, equation (n2-1) can also be cited:

[0188] [Chemistry 8]

[0189]

[0190] (where X) 9 For H, F, or CH3; Rf 4 It is a fluorinated acrylate monomer represented by a fluorinated alkyl group having 1 to 40 carbon atoms or a fluorinated alkyl group having an ether bond having 2 to 100 carbon atoms. The above Rf4 The base can be cited as an example

[0191] [Chemistry 9]

[0192]

[0193] (where Z) 8 (H, F, or C1; d1 is an integer from 1 to 4; e1 is an integer from 1 to 10), -CH(CF3)2,

[0194]

[0195] (In the formula, e2 is an integer from 1 to 5)

[0196]

[0197] (In the formula, d3 is an integer from 1 to 4; e3 is an integer from 1 to 10) etc.

[0198] As for the other monomers mentioned above, equation (n2-2) can also be cited:

[0199] CH2=CHO-Rf 5 (n2-2)

[0200] (where Rf) 5 It is a fluorinated vinyl ether represented by a fluorinated alkyl group having 1 to 40 carbon atoms or a fluorinated alkyl group having ether bonds having 2 to 100 carbon atoms.

[0201] As a single entity in formula (n2-2), specifically, preferred examples can be cited.

[0202] [Chemistry 10]

[0203]

[0204] (where Z) 9 (e4 is an integer from 1 to 10)

[0205]

[0206] (In the formula, e5 is an integer from 1 to 10)

[0207]

[0208] (In the formula, e6 is an integer from 1 to 10) etc.

[0209] More specifically, examples can be given.

[0210] [Chemistry 11]

[0211] CH2=CHOCH2CF2CF2H、

[0212]

[0213] CH2=CHOCH2CF2CF3、

[0214] CH2=CHOCH2CF3、

[0215]

[0216] wait.

[0217] Alternatively, equation (n²-3) can also be cited:

[0218] CH2=CHCH2O-Rf 6 (n2-3)

[0219] (where Rf) 6 Fluorinated allyl ethers of formula (n2-4) are fluorinated alkyl groups having 1 to 40 carbon atoms or fluorinated alkyl groups having ether bonds having 2 to 100 carbon atoms.

[0220] CH2=CH-Rf 7 (n2-4)

[0221] (where Rf) 7 Fluorinated vinyl monomers, etc., are fluorinated alkyl groups having 1 to 40 carbon atoms or fluorinated alkyl groups having ether bonds having 2 to 100 carbon atoms.

[0222] Specifically, as the monomers shown in equations (n2-3) and (n2-4) above, examples can be given as follows:

[0223] [Chemistry 12]

[0224] CH2=CHCH2OCH2CF2CF2H、

[0225]

[0226] CH2=CHCH2OCH2CF2CF3、

[0227] CH2=CHCH2OCH2CF3、

[0228]

[0229] Monomers, etc.

[0230] In polymer (1), the content of polymeric unit (1) relative to all polymeric units is preferably 1.0 mol% or more, more preferably 3.0 mol% or more, further preferably 5.0 mol% or more, even more preferably 10 mol% or more, particularly preferably 20 mol% or more, especially preferably 30 mol% or more. More preferably 40 mol% or more, further preferably 60 mol% or more, even more preferably 80 mol% or more, especially preferably 90 mol% or more, substantially especially preferably 100 mol%.

[0231] In polymer (1), the content of polymerization units based on other monomers capable of copolymerizing with the monomers shown in general formula (1) is preferably 70 mol% or less, more preferably 60 mol% or less, further preferably 40 mol% or less, even more preferably 20 mol% or less, particularly preferably 10 mol% or less, and substantially especially preferably 0 mol% relative to all polymerization units.

[0232] The number-average molecular weight of the polymer (1) is preferably 0.1 × 10⁻⁶. 4 The above, and more preferably 0.2×10 4 The above, and more preferably 0.3×10 4 The above, and even more preferably, is 0.4 × 10 4 The above, and especially preferred, is 0.5 × 10⁻⁶. 4 The above, and especially preferred, is 1.0 × 10 4 The above, and the optimal value, is 3.0 × 10. 4 That's all. Additionally, 75.0 × 10 is preferred. 4 The following, or more preferably, is 50.0 × 10 4 The following, and more preferably 30.0 × 10 4 The following, particularly preferred, is 20.0 × 10 4 The following applies. If the number average molecular weight is too low, the stability of the aqueous solution may be insufficient. If the number average molecular weight is too high, the polymer (1) may partially precipitate, precipitate, or become cloudy due to storage or the addition of other additives.

[0233] The number-average molecular weight mentioned above and the weight-average molecular weight mentioned later are values ​​obtained by calculating the molecular weight using gel permeation chromatography (GPC) with monodisperse polystyrene as the standard.

[0234] The weight-average molecular weight of the polymer (1) is preferably 0.2 × 10⁻⁶. 4 The above, and more preferably 0.4×10 4 The above, and more preferably 0.6×10 4 The above, and especially preferred, is 0.8×10 4 The above, and especially preferred, is 1.0 × 10 4That's all. Additionally, 150.0 × 10 is preferred. 4 The following, or more preferably, is 100.0 × 10 4 The following, and more preferably, is 60.0 × 10 4 The following, particularly preferred, is 40.0 × 10 4 the following.

[0235] The polymer (1) described above can be manufactured by existing known methods, except for the monomers described above.

[0236] The method for manufacturing the fluoropolymer of the present invention includes the following steps: in the presence of a polymer (1) containing a polymerization unit (1), a fluorinated monomer is polymerized in an aqueous medium to obtain the fluoropolymer, wherein the polymerization unit (1) is based on a monomer represented by the following general formula (1).

[0237] As the aforementioned fluorinated monomer, it is preferred to have at least one double bond.

[0238] The preferred fluorinated monomers are selected from tetrafluoroethylene [TFE], hexafluoropropylene [HFP], trifluorochloroethylene [CTFE], fluoroethylene, vinylidene fluoride [VDF], trifluoroethylene, fluoroalkyl vinyl ether, fluoroalkyl ethylene, trifluoropropylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutylene, hexafluoroisobutylene, and general formula (100): CH2=CFRf 101 (where Rf) 101 It is at least one of the following groups: fluorinated monomers (represented by straight-chain or branched fluorinated alkyl groups having 1 to 12 carbon atoms), fluorinated vinyl heterocyclic compounds, and monomers that provide crosslinking sites.

[0239] As the above-mentioned fluoroalkyl vinyl ether, at least one of the following fluorinated monomers is preferred, for example:

[0240] General formula (110): CF2 = CF - ORf 111

[0241] (where Rf) 111 Fluorinated monomers (representing perfluorinated organic groups)

[0242] General formula (120): CF2=CF-OCH2-Rf 121

[0243] (where Rf) 121 Fluorinated monomers (represented by perfluoroalkyl groups having 1 to 5 carbon atoms)

[0244] General formula (130): CF2=CFOCF2ORf 131

[0245] (where Rf)131 It refers to fluorinated monomers represented by straight-chain or branched perfluoroalkyl groups having 1 to 6 carbon atoms, cyclic perfluoroalkyl groups having 5 to 6 carbon atoms, and straight-chain or branched perfluorooxyalkyl groups having 2 to 6 carbon atoms containing 1 to 3 oxygen atoms.

[0246] General formula (140): CF2=CFO(CF2CF(Y 141 )O) m (CF2) n F

[0247] (where Y) 141 Represents a fluorine atom or a trifluoromethyl group. m is an integer from 1 to 4. n is an integer from 1 to 4. The fluorine-containing monomers shown are...

[0248] General formula (150): CF2=CF-O-(CF2CFY) 151 -O) n -(CFY 152 ) m -A 151

[0249] (where Y) 151 This indicates a fluorine atom, a chlorine atom, a -SO2F group, or a perfluoroalkyl group. Perfluoroalkyl groups may contain ether-like oxygen atoms and -SO2F groups. n represents an integer from 0 to 3. n Y atoms 151 They can be the same or different. Y 152 Represents a fluorine atom, a chlorine atom, or a -SO2F group. m represents an integer from 1 to 5. m Y atoms 152 They can be the same or different. A 151 Indicates -SO2X 151 -COZ 151 or -POZ 152 Z 153 X 151 Represents F, Cl, Br, I, -OR 151 or -NR 152 R 153 Z 151 Z 152 and Z 153 Same or different, indicating -NR 154 R 155 or -OR 156 R 151 R 152 R 153 R 154 R 155 and R 156 The same or different refers to fluorine-containing monomers represented by H, ammonium, alkali metal, alkyl, aryl or sulfonyl groups (with or without fluorine atoms).

[0250] In this specification, "perfluorinated organic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are replaced by fluorine atoms. The aforementioned perfluorinated organic group may contain ether oxygen.

[0251] As a fluorinated monomer represented by general formula (110), Rf can be cited as an example. 111 It is a fluorinated monomer of a perfluoroalkyl group having 1 to 10 carbon atoms. The preferred number of carbon atoms in the perfluoroalkyl group is 1 to 5.

[0252] Examples of perfluorinated organic groups in general formula (110) include perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, and perfluorohexyl.

[0253] As a fluorinated monomer represented by general formula (110), Rf in the above general formula (110) can be further cited as an example. 111 It is a perfluorinated (alkoxyalkyl) monomer with 4 to 9 carbon atoms, Rf 111 It is the following formula:

[0254] [Chemistry 13]

[0255]

[0256] (where m represents 0 or an integer from 1 to 4) the monomer of the group shown, Rf 111 It is the following formula:

[0257] [Chemistry 14]

[0258]

[0259] Monomers of groups shown in the formula (where n represents an integer from 1 to 4).

[0260] As a fluorinated monomer represented by general formula (110), wherein general formula (160) is preferred: CF2=CF-ORf 161

[0261] (where Rf) 161 The fluorinated monomer (representing a perfluoroalkyl group having 1 to 10 carbon atoms) is shown as Rf. 161 The preferred form is a perfluoroalkyl group having 1 to 5 carbon atoms.

[0262] As a fluoroalkyl vinyl ether, it is preferably at least one selected from the group consisting of fluorinated monomers represented by general formulas (160), (130) and (140).

[0263] As the fluorinated monomer represented by general formula (160), it is preferably selected from at least one of the group consisting of perfluorinated (methyl vinyl ether), perfluorinated (ethyl vinyl ether) and perfluorinated (propyl vinyl ether), and more preferably from at least one of the group consisting of perfluorinated (methyl vinyl ether) and perfluorinated (propyl vinyl ether).

[0264] As the fluorinated monomer represented by general formula (130), it is preferably at least one selected from the group consisting of CF2=CFOCF2OCF3, CF2=CFOCF2OCF2CF3 and CF2=CFOCF2OCF2CF2OCF3.

[0265] As the fluorinated monomer represented by general formula (140), it is preferably at least one selected from the group consisting of CF2=CFOCF2CF(CF3)O(CF2)3F, CF2=CFO(CF2CF(CF3)O)2(CF2)3F and CF2=CFO(CF2CF(CF3)O)2(CF2)2F.

[0266] As the fluorinated monomer represented by general formula (150), it is preferably selected from at least one of the group consisting of CF2=CFOCF2CF2SO2F, CF2=CFOCF2CF(CF3)OCF2CF2SO2F, CF2=CFOCF2CF(CF2CF2SO2F)OCF2CF2SO2F and CF2=CFOCF2CF(SO2F)2.

[0267] Rf is preferred as the fluorinated monomer represented by general formula (100). 101 It is a straight-chain fluorinated alkyl fluorinated monomer, more preferably Rf 101 It is a straight-chain perfluoroalkyl fluorinated monomer. Rf 101 The number of carbon atoms is preferably 1 to 6. Examples of fluorinated monomers represented by general formula (100) include CH2=CFCF3, CH2=CFCF2CF3, CH2=CFCF2CF2CF3, CH2=CFCF2CF2CF2H, CH2=CFCF2CF2CF2CF3, etc., among which 2,3,3,3-tetrafluoropropylene represented by CH2=CFCF3 is preferred.

[0268] As a fluoroalkyl ethylene, the preferred formula is (170): CH2=CH-(CF2). n- X 171

[0269] (where X) 171 Fluoroalkyl ethylene (where H or F, n is an integer from 3 to 10) is more preferably selected from CH2=CH-C4F9 and CH2=CH-C6F9. 13 At least one of the groups.

[0270] The monomer providing the crosslinking site is preferably at least one selected from the group consisting of:

[0271] General formula (180): CX 181 2 = CX 182 -R f 181 CHR 181 X 183

[0272] (where X) 181 and X 182 Independently, it can be a hydrogen atom, a fluorine atom, or CH3, R f 181 It is a fluoroalkylene, perfluoroalkylene, fluoro(poly)oxyalkylene, or perfluoro(poly)oxyalkylene, R 181 For hydrogen atoms or CH3, X 183 Fluorine-containing monomers (represented by iodine or bromine atoms)

[0273] General formula (190): CX 191 2 = CX 192 -R f 191 X 193

[0274] (where X) 191 and X 192 Independently, it can be a hydrogen atom, a fluorine atom, or CH3, R f 191 It is a fluoroalkylene, perfluoroalkylene, fluoropolyoxyalkylene, or perfluoropolyoxyalkylene, X 193 Fluorine-containing monomers (represented by iodine or bromine atoms)

[0275] General formula (200): CF2 = CFO(CF2CF(CF3)O) m (CF2) n- X 201

[0276] (In the formula, m is an integer from 0 to 5, n is an integer from 1 to 3, X) 201 Fluorine-containing monomers represented by cyano, carboxyl, alkoxycarbonyl, iodine, bromine, or -CH2I, and

[0277] General formula (210): CH2=CFCF2O(CF(CF3)CF2O) m (CF(CF3)) n- X 211

[0278] (In the formula, m is an integer from 0 to 5, n is an integer from 1 to 3, X)211 Fluorine-containing monomers represented by cyano, carboxyl, alkoxycarbonyl, iodine, bromine, or -CH2OH, and

[0279] General formula (220): CR 221 R 222 =CR 223 -Z 221 -CR 224 =CR 225 R 226

[0280] (where R is in the formula) 221 R 222 R 223 R 224 R 225 and R 226 Whether the groups are the same or different, they are either alkyl groups with 1 to 5 hydrogen atoms or carbon atoms. Z 221 It is a straight-chain or branched alkylene group with or without oxygen atoms, having 1 to 18 carbon atoms, a cycloalkylene group with 3 to 18 carbon atoms, an alkylene group with at least partially fluorinated carbon atoms with 1 to 10 carbon atoms, or an alkylene oxide group, or

[0281] -(Q) p -CF₂O-(CF₂CF₂O) m (CF2O) n -CF2-(Q) p -

[0282] (In the formula, Q is an alkylene or alkylene oxide. p is 0 or 1. m / n is 0.2 to 5) The monomers shown are (per)fluoropolyalkylene oxides with a molecular weight of 500 to 10000.

[0283] X 183 and X 193 Preferably, it contains an iodine atom. R f 181 and R f 191 Preferably, it is a perfluoroalkylene group having 1 to 5 carbon atoms. 181 Preferably, it contains hydrogen atoms. X 201 Preferably, it consists of a cyano group, an alkoxycarbonyl group, an iodine atom, a bromine atom, or -CH2I. X 211 Preferably, it is a cyano group, an alkoxycarbonyl group, an iodine atom, a bromine atom, or -CH2OH.

[0284] Examples of the above-mentioned fluorinated vinyl heterocyclic compounds include general formula (230):

[0285] [Chemistry 15]

[0286]

[0287] (where X) 231 and X 232 Y can be independently F, Cl, methoxy, or fluoromethoxy. 231 For formula Y 232 or Y 233 .

[0288] [Chemistry 16]

[0289]

[0290] (where Z) 231 and Z 232 Fluorinated vinyl heterocyclic compounds that are independently represented by F or fluoroalkyl groups having 1 to 3 carbon atoms.

[0291] The monomers providing the crosslinking sites are preferably selected from CF2=CFOCF2CF(CF3)OCF2CF2CN, CF2=CFOCF2CF(CF3)OCF2CF2COOH, CF2=CFOCF2CF(CF3)OCF2CF2CH2I, CF2=CFOCF2CF2CH2I, CH2=CFCF2OCF(CF3)CF2OCF(CF3)CN, CH2=CFCF2OCF(CF3)CF2OCF(CF3)COOH, CH2=CFCF2OCF(CF3)CF2OCF(CF3)CH2OH, and CH2=CHCF2CF2I. At least one of the group consisting of CH2=CH(CF2)2CH=CH2, CH2=CH(CF2)6CH=CH2 and CF2=CFO(CF2)5CN, more preferably at least one of the group consisting of CF2=CFOCF2CF(CF3)OCF2CF2CN and CF2=CFOCF2CF2CH2I.

[0292] In the above process, the fluorinated monomer and the non-fluorinated monomer can be polymerized. Examples of non-fluorinated monomers include hydrocarbon monomers that are reactive with the fluorinated monomers. Examples of hydrocarbon monomers include: olefins such as ethylene, propylene, butene, and isobutylene; alkyl vinyl ethers such as ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether, and cyclohexyl vinyl ether; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl valerate, vinyl neopentanoate, vinyl hexanoate, vinyl octanoate, vinyl decanoate, vinyl tert-carbonate, vinyl laurate, vinyl tetradecanoate, vinyl palmitate, vinyl stearate, vinyl benzoate, p-tert-butylbenzoate, vinyl cyclohexanecarboxylate, and monochloroacetic acid. Vinyl esters such as vinyl esters, vinyl adipate, vinyl acrylate, vinyl methacrylate, vinyl butenoate, vinyl sorbate, vinyl cinnamate, vinyl undecenoate, vinyl glycol acetate, vinyl hydroxypropionate, vinyl hydroxybutyrate, vinyl hydroxyvalerate, vinyl hydroxyisobutyrate, and vinyl hydroxycyclohexanecarboxylate; alkyl allyl ethers such as ethyl allyl ether, propyl allyl ether, butyl allyl ether, isobutyl allyl ether, and cyclohexyl allyl ether; alkyl allyl esters such as ethyl allyl ester, propyl allyl ester, butyl allyl ester, isobutyl allyl ester, and cyclohexyl allyl ester; and so on.

[0293] In addition, the aforementioned non-fluorinated monomers can also be hydrocarbon monomers containing functional groups (excluding monomers that provide crosslinking sites). Examples of such hydrocarbon monomers containing functional groups include: hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, hydroxyisobutyl vinyl ether, and hydroxycyclohexyl vinyl ether; non-fluorinated monomers with carboxyl groups such as itaconic acid, succinic acid, succinic anhydride, fumaric acid, fumaric anhydride, butenoic acid, maleic acid, maleic anhydride, and perfluorobutenoic acid; non-fluorinated monomers with glycidyl groups such as glycidyl vinyl ether and glycidyl allyl ether; non-fluorinated monomers with amino groups such as aminoalkyl vinyl ether and aminoalkyl allyl ether; non-fluorinated monomers with amide groups such as (meth)acrylamide and hydroxymethylacrylamide; and so on.

[0294] In the above process, by polymerizing one or more of the fluorinated monomers, the desired fluorinated polymer particles can be obtained.

[0295] When the manufacturing method of the present invention uses at least one of the above-described polymers (1), it can effectively manufacture fluoropolymers. In addition, in the manufacturing method of the present invention, two or more of the above-described polymers (1) can be used simultaneously, as long as they are volatile polymers or polymers that can remain in molded articles made of fluoropolymers, etc., and other compounds with surface-active properties can also be used simultaneously.

[0296] In the manufacturing method of the present invention, the above polymerization can also be carried out in the presence of a nonionic surfactant. Preferably, the nonionic surfactant is at least one selected from the group consisting of:

[0297] General formula (240): Rf 241 -(X 241 ) n -Y 241

[0298] (where Rf) 241 It is a partially fluorinated or fully fluorinated alkyl group having 1 to 12 carbon atoms, where n is 0 or 1, and X 241 Y is -O-, -COO-, or -OCO-. 241 -(CH2) p H, -(CH2) p OH or -(OR) 241 ) q (OR 242 ) r OH, p is an integer from 1 to 12, q is an integer from 1 to 12, r is an integer from 0 to 12, R 241 and R 242 It is an alkylene group having 2 to 4 carbon atoms. Wherein R... 241 and R 242 The compounds shown are different from each other.

[0299] General formula (250): H(OR) 251 ) u (OR 252 ) v OH

[0300] (where R is in the formula) 251 and R 252 It is an alkylene group having 1 to 4 carbon atoms, where u and v are integers from 1 to 5. Where R... 251 and R 252 Block polymers (which are different from each other) are shown.

[0301] Nonionic surfactants containing hydrophobic groups composed of hydrocarbon groups with 8 to 20 carbon atoms and hydrophilic groups composed of polyepoxides within their molecules, and

[0302] General formula (260): R 261 m -Si-(OR 262 ) 4-m

[0303] (where R is in the formula) 261 R is an alkyl group having 1 to 12 carbon atoms. 262The silicon compound is shown as an alkyl group having 1 to 4 carbon atoms, where m is an integer from 1 to 3.

[0304] As a block polymer represented by general formula (250), specific examples include block polymers composed of at least two segments selected from the group consisting of polyethylene oxide, polypropylene oxide, and polybutylene oxide. Examples include polyethylene oxide-polypropylene oxide block polymers and polyethylene oxide-polybutylene oxide block polymers; AB-type block polymers and ABA-type block polymers are also preferred examples. It is further preferred that a stable dispersion of the fluoropolymer can be prepared at a high concentration using polyethylene oxide-polypropylene oxide block polymers and polypropylene oxide-polyethylene oxide-polypropylene oxide block polymers. Furthermore, a polyethylene oxide segment content of 10-50% is considered to result in less agglomerate formation due to re-agglomeration, and is therefore preferred; furthermore, a content of 20-40% allows for the preparation of a low-viscosity dispersion of the fluoropolymer, which is also preferred. There are no particular restrictions on molecular weight, as long as it is between 1000 and 7000 g / mol; and especially when the molecular weight is between 2500 and 6500 g / mol, dispersions with low viscosity and excellent dispersibility can be prepared.

[0305] Nucleating agents can be used in the manufacturing method of the present invention. The preferred amount of the nucleating agent can be appropriately selected according to the type of nucleating agent. For example, it is 1000 ppm or less relative to the aqueous medium, more preferably 500 ppm or less, further preferably 100 ppm or less, particularly preferably 50 ppm or less, and especially preferably 10 ppm or less.

[0306] The manufacturing method of the present invention preferably further includes the following step: adding a nucleating agent to the aqueous medium before polymerization begins, or when the concentration of polytetrafluoroethylene particles formed in the aqueous medium is less than 5.0% by mass. By adding a nucleating agent at the initial stage of polymerization, an aqueous dispersion with small average primary particle size and excellent stability can be obtained.

[0307] The amount of nucleating agent added before polymerization begins, or when the concentration of PTFE particles formed in the aqueous medium is less than 5.0% by mass, is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, further preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more relative to the obtained polytetrafluoroethylene. There is no upper limit, for example, 2000% by mass.

[0308] By using the above-mentioned nucleating agent, a fluoropolymer with a smaller primary particle size can be obtained compared to polymerization in the absence of the above-mentioned nucleating agent.

[0309] Examples of nucleating agents include dicarboxylic acids, perfluoropolyether (PFPE) acids or their salts, and hydrocarbon-containing surfactants. Preferably, the nucleating agent does not contain an aromatic ring and is preferably an aliphatic compound.

[0310] The nucleating agent is preferably added before or simultaneously with the polymerization initiator. Alternatively, it can be added during polymerization to adjust the particle size distribution.

[0311] The preferred amount of the dicarboxylic acid is 1000 ppm or less relative to the aqueous medium, the more preferred amount is 500 ppm or less, and the even more preferred amount is 100 ppm or less.

[0312] The aforementioned perfluoropolyether (PFPE) acids or their salts can have any chain structure in which oxygen atoms in the main chain of the molecule are separated by saturated fluorinated carbomers having 1 to 3 carbon atoms. Furthermore, two or more types of fluorinated carbomers can be present in the molecule. A representative structure has repeating units as shown in the following formula.

[0313] (-CFCF3-CF2-O-) n (VII)

[0314] (-CF2-CF2-CF2-O-) n (VIII)

[0315] (-CF2-CF2-O-) n -(-CF2-O-) m (IX)

[0316] (-CF2-CFCF3-O-) n -(-CF2-O-) m (X)

[0317] These structures are described by Kasai in J. Appl. Polymer Sci. 57, 797 (1995). As disclosed in that document, the aforementioned PFPE acid or its salt may have a carboxylic acid group or its salt at one or both ends. The aforementioned PFPE acid or its salt may also have a sulfonic acid group, a phosphonic acid group or its salt at one or both ends. In addition, the aforementioned PFPE acid or its salt may have different groups at each end. With regard to monofunctional PFPE, the other end of the molecule is usually perfluorinated and may also contain hydrogen or chlorine atoms. The aforementioned PFPE acid or its salt has at least 2 ether oxygen atoms, preferably at least 4 ether oxygen atoms, and more preferably at least 6 ether oxygen atoms. Preferably, at least one of the fluorinated carbon groups separating the ether oxygen atoms, more preferably at least two of such fluorinated carbon groups, has 2 or 3 carbon atoms. More preferably, at least 50% of the fluorinated carbon groups separating the ether oxygen atoms have 2 or 3 carbon atoms. Furthermore, the PFPE acid or its salt preferably has a total of at least 15 carbon atoms; for example, the minimum value of n or n+m in the repeating unit structure is preferably at least 5. Two or more of the PFPE acid or its salt having an acid group at one or both ends can be used in the manufacturing method of the present invention. The PFPE acid or its salt preferably has a number-average molecular weight of less than 6000 g / mol.

[0318] Compared to the aforementioned aqueous medium, the amount of the hydrocarbon-containing surfactant added is preferably 40 ppm or less, more preferably 30 ppm or less, and even more preferably 20 ppm or less. It is presumed that the amount of lipophilic nucleating sites present in the aforementioned aqueous medium is less than the aforementioned added amount. Therefore, the amount of the lipophilic nucleating sites is less than the aforementioned 50 ppm, 40 ppm, 30 ppm, and 20 ppm, respectively. Since the lipophilic nucleating sites exist as molecules, even a very small amount of the aforementioned hydrocarbon-containing surfactant can generate a large number of lipophilic nucleating sites. Therefore, even adding only about 1 ppm of the aforementioned hydrocarbon-containing surfactant to the aqueous medium can yield beneficial effects. The preferred lower limit is 0.01 ppm, more preferably 0.1 ppm.

[0319] The aforementioned hydrocarbon-containing surfactants include siloxane surfactants such as those disclosed in U.S. Patent No. 7,897,682 (Brothers et al.) and U.S. Patent No. 7,977,438 (Brothers et al.), including nonionic surfactants and cationic surfactants.

[0320] As the aforementioned hydrocarbon-containing surfactant, a nonionic surfactant (e.g., a nonionic hydrocarbon surfactant) is preferred. That is, as a nucleating agent, a nonionic surfactant is preferred. The aforementioned nonionic surfactant preferably does not contain an aromatic moiety.

[0321] Examples of nonionic surfactants include, for example, the following general formula (i).

[0322] R 3 -OA 1 -H(i)

[0323] (where R is in the formula) 3 It is a straight-chain or branched primary or secondary alkyl group with 8 to 18 carbon atoms, A 1 The compound shown is a polyoxyethylene chain.

[0324] R 3 The number of carbon atoms is preferably 10 to 16, more preferably 12 to 16. If R 3 When the number of carbon atoms is 18 or less, it is easy to obtain good dispersion stability in aqueous dispersions. Additionally, if R... 3 If the number of carbon atoms exceeds 18, the flow temperature is high, making it difficult to process. If R 3 If the number of carbon atoms is less than 8, the surface tension of the aqueous dispersion will increase, and its permeability and wettability will easily decrease.

[0325] Polyoxyethylene chains can be composed of ethylene oxide and propylene oxide. A polyoxyethylene chain is composed of an average repeating number of 5–20 for vinyl oxide groups and an average repeating number of 0–2 for propylene oxide groups, and consists of hydrophilic groups. The number of ethylene oxide units can include either a commonly provided broad or narrow unimodal distribution, or a broader or bimodal distribution obtained through blending. When the average repeating number of propylene oxide groups exceeds 0, the vinyl oxide and propylene oxide groups in the polyoxyethylene chain can be arranged in a block or random configuration.

[0326] From the perspective of viscosity and stability of the aqueous dispersion, polyoxyethylene chains composed of an average repeating number of 7 to 12 for vinyl oxides and an average repeating number of 0 to 2 for propylene oxides are preferred. In particular, if A 1 Having an average of 0.5 to 1.5 propylene oxide groups results in good low foaming properties, making it a preferred choice.

[0327] More preferably R 3 The formula is (R')(R”)HC-, where R' and R” are the same or different straight-chain, branched, or cyclic alkyl groups, and the total number of carbon atoms is at least 5, preferably 7 to 17. Preferably, at least one of R' or R” is a branched or cyclic hydrocarbon group.

[0328] As a specific example of the aforementioned polyoxyethylene alkyl ethers, C can be cited. 13 H 27 -O-(C2H4O) 10 -H, C 12 H 25 -O-(C2H4O)10 -H, C 10 H 21 CH(CH3)CH2-O-(C2H4O)9-H, C 13 H 27 -O-(C2H4O)9-(CH(CH3)CH2O)-H,C 16 H 33 -O-(C2H4O) 10 -H, HC(C5H) 11 (C7H) 15 Examples of commercially available polyoxyethylene alkyl ethers include Genapol X080 (manufactured by Clariant), the Noigen TDS series (manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.) with Noigen TDS-80 as an example, the Leocol TD series (manufactured by LION) with Leocol TD-90 as an example, the LIONOL TD series (manufactured by LION), the T-Det A series (manufactured by Harcros Chemicals) with T-Det A138 as an example, and the TERGITOL 15S series (manufactured by Dow Chemical Co., Ltd.).

[0329] The aforementioned nonionic surfactants are preferably ethoxylated derivatives of 2,6,8-trimethyl-4-nonanol having an average of about 4 to about 18 ethylene oxide units, ethoxylated derivatives of 2,6,8-trimethyl-4-nonanol having an average of about 6 to about 12 ethylene oxide units, or mixtures thereof. This type of nonionic surfactant is also commercially available, for example, as TERGITOL TMN-6, TERGITOL TMN-10, and TERGITOL TMN-100X (all product names, manufactured by Dow Chemical Company).

[0330] In addition, the hydrophobic group of a nonionic surfactant can be any one of alkylphenol, straight-chain alkyl, and branched-chain alkyl.

[0331] For example, examples of nonionic compounds based on polyoxyethylene alkylphenyl ethers include those of the following general formula (ii).

[0332] R 4 -C6H4-OA 2 -H(ii)

[0333] (where R is in the formula) 4 It is a straight-chain or branched primary or secondary alkyl group with 4 to 12 carbon atoms, A 2The compound is shown as a polyoxyethylene alkylphenyl ether. Examples of the above-mentioned nonionic polyoxyethylene alkylphenyl ether compounds include TRITONX-100 (trade name, manufactured by Dow Chemical).

[0334] Polyol compounds can also be cited as nonionic surfactants. Specifically, polyol compounds described in International Publication No. 2011 / 014715 can be cited.

[0335] Typical examples of polyol compounds include compounds having one or more sugar units as polyol units. The sugar units can be modified to contain at least one long chain. Suitable polyol compounds containing at least one long chain moiety include, for example, alkyl glycosides, modified alkyl glycosides, sugar esters, and combinations thereof. Examples of sugars include monosaccharides, oligosaccharides, and sorbitan, but are not limited to these. Examples of monosaccharides include pentoses and hexoses. Typical examples of monosaccharides include ribose, glucose, galactose, mannose, fructose, arabinose, and xylose. Examples of oligosaccharides include oligosaccharides of 2 to 10 identical or different monosaccharides. Examples of oligosaccharides include sucrose, maltose, lactose, raffinose, and isomaltose, but are not limited to these.

[0336] Typically, sugars suitable for use as polyol compounds include cyclic compounds with a five-membered ring containing four carbon atoms and one heteroatom (typically oxygen or sulfur, preferably oxygen), or cyclic compounds with a six-membered ring containing five carbon atoms and the aforementioned heteroatom, preferably oxygen. They further contain at least two or at least three hydroxyl groups (-OH groups) bonded to the carbon ring atoms. Typically, to form an ether or ester bond between the long-chain residues and the sugar moiety, the sugar is modified in that one or more hydrogen atoms of the hydroxyl (and / or hydroxyalkyl) groups bonded to the carbon ring atoms are replaced by long-chain residues.

[0337] Sugar-based polyols may contain one or more sugar units. One or more sugar units may be modified using the aforementioned long-chain moiety. Specific examples of sugar-based polyol compounds include glycosides, sugar esters, sorbitan esters, and mixtures and combinations thereof.

[0338] Preferred types of polyol compounds are alkyl or modified alkyl glucosides. These types of surfactants contain at least one glucose moiety. Examples include...

[0339] [Chemistry 17]

[0340]

[0341] (In the formula, x represents 0, 1, 2, 3, 4, or 5, R)1 and R 2 Independently represents H or a long-chain unit containing at least 6 carbon atoms, where R 1 and R 2 At least one of the compounds shown in the diagram is not H. As R 1 and R 2 Typical examples include aliphatic alcohol residues. Examples of aliphatic alcohols include hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol (lauryl alcohol), tetradecanol, hexadecanol (cetyl alcohol), heptadecanol, octadecanol (stearyl alcohol), eicosanoic acid, and combinations thereof.

[0342] The above formula shows a specific example of an alkyl polyglucan representing glucose in the form of pyranose, but it is understood that other sugars or sugars that are the same sugar but in different mirror isomers or diastereomers may also be used.

[0343] Alkyl glucosides can be obtained, for example, by acid-catalyzed reactions of glucose, starch, or n-butyl glucoside with aliphatic alcohols, typically yielding mixtures of various alkyl glucosides (Alkylpolygylcoside, Rompp, Lexikon Chemie, Version 2.0, Stuttgart / New York, Georg Thieme Verlag, 1999). Examples of aliphatic alcohols include hexanol, heptanol, octanol, nonanol, decanol, undecaneol, dodecaneol (laurate), tetradecaneol, hexadecaneol (cetyl alcohol), heptadecanol, octadecaneol (stearyl), eicosanoic acid, and combinations thereof. Alkyl glucosides are also commercially available from Cognis GmbH in Düsseldorf, Germany, under the trade names GLUCOPON or DISPONIL.

[0344] Other nonionic surfactants include difunctional block copolymers supplied by BASF as part of the Pluronic (registered trademark) R series, tridecyl alcohol alkoxylates supplied by BASF as part of the Iconol (registered trademark) TDA series, hydrocarbon-containing siloxane surfactants, and preferably hydrocarbon surfactants. Here, in cases where the hydrocarbon group can be replaced by halogens such as fluorine, it is completely replaced by hydrogen atoms. Thus, these siloxane surfactants can also be regarded as hydrocarbon surfactants, that is, the monovalent substituent on the hydrocarbon group is hydrogen.

[0345] Furthermore, when using TFE as a fluorinated monomer and manufacturing polytetrafluoroethylene [PTFE] as a fluorinated polymer, at the beginning of TFE polymerization, by including (polyfluoroalkyl) ethylene (a) and / or a comonomer (b) with a monomer reactivity ratio rTFE of 0.1 to 8 with TFE in the copolymerization system at a rate of 0.001 to 0.01% by mass relative to the final PTFE production, an aqueous PTFE dispersion with high stability can be produced without impairing subsequent processability, moldability, etc., and with high heat resistance of molded products can be obtained.

[0346] Here, the monomer reactivity ratio in the copolymerization with TFE is obtained as follows: when the number of growth radicals is less than the number of repeating units based on TFE, the rate constant of the reaction between the growth radical and TFE is divided by the rate constant of the reaction between the growth radical and the comonomer. The resulting value is the monomer reactivity ratio. The lower this value, the higher the reactivity between the comonomer and TFE. The reactivity ratio can be calculated as follows: copolymerize the comonomer with TFE with various feed compositions, determine the composition of the polymer formed at the beginning of copolymerization, and calculate the reactivity ratio using the Fineman-Ross formula based on the composition.

[0347] The copolymerization was carried out in a 6.0L stainless steel autoclave using 3600g of deionized degassed water, 1000ppm of ammonium perfluorooctanoate relative to the water, and 100g of paraffin wax at a pressure of 0.78MPa and a temperature of 70°C. Comonomers of 0.05g, 0.1g, 0.2g, 0.5g, and 1.0g were added to the reactor, along with 0.072g of ammonium persulfate (20ppm relative to water). To maintain a polymerization pressure of 0.78MPa, TFE was continuously supplied. After 1000g of TFE was added, stirring was stopped, and depressurization was performed until the reactor reached atmospheric pressure. After cooling, the paraffin wax was separated, yielding an aqueous dispersion containing the polymer. The aqueous dispersion was stirred to precipitate the polymer, which was then dried at 150°C. The composition of the resulting polymer was calculated by appropriately combining NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis based on the monomer type.

[0348] In the manufacturing method of the present invention, a compound having functional groups and hydrophilic groups capable of undergoing free radical polymerization can be used with the polymer (1) described above. Examples of functional groups capable of undergoing free radical polymerization include groups having unsaturated bonds such as vinyl and allyl groups. Details are described below.

[0349] Examples of hydrophilic groups include -NH2, -PO3M, -OPO3M, -SO3M, -OSO3M, and -COOM (where M represents H, NH4, or an alkali metal). Among these, -SO3M or -COOM are preferred. Examples of alkali metals include Na and K.

[0350] Examples of compounds possessing functional groups and hydrophilic groups capable of undergoing free radical polymerization include, for example, those of general formula (270a):

[0351] CF2 = CF - (CF2) n271a -Y 271

[0352] (In the formula, n271a represents an integer from 1 to 10, Y) 271 Indicates -SO3M 271 or -COOM 271 M 271 Surfactants represented by H, NH4, or alkali metals, general formula (270b):

[0353] CF2 = CF - (CF2C(CF3)F) n271b -Y 271

[0354] (In the formula, n271b represents an integer from 1 to 5, Y) 271 Surfactants of the same formula (270c) as defined above:

[0355] CF2 = CF-O-(CFX) 271 ) n271c -Y 271

[0356] (where X) 271 Indicates F or CF3, n271c represents an integer from 1 to 10, Y 271 Surfactants of the same formula (270d) as defined above:

[0357] CF2 = CF-O-(CF2CFX) 271 O) n271d -CF2CF2-Y 271

[0358] (In the formula, n271d represents an integer from 1 to 10, Y) 271 and X 271 Surfactants of the same formula as defined above, general formula: (270e):

[0359] CX 272 2=CFCF2-O-(CF(CF3)CF2O)n271e -CF(CF3)-Y 271

[0360] (In the formula, each X) 272 Same, indicating F or H. n271e represents 0 or an integer from 1 to 10, Y 271 Compounds, etc. (as defined above).

[0361] Furthermore, in the manufacturing method of the present invention, in addition to the polymer (1) described above and other compounds with surface-active capabilities as desired, additives for stabilizing each compound may also be used. Examples of such additives include buffers, pH adjusters, stabilizing agents, and dispersing stabilizers.

[0362] Preferred stabilizing agents include paraffin wax, fluorinated oils, fluorinated solvents, and silicone oils. One stabilizing agent can be used alone or in combination of two or more. Paraffin wax is more preferred. Paraffin wax can be liquid, semi-solid, or solid at room temperature, but is preferably a saturated hydrocarbon with 12 or more carbon atoms. The melting point of paraffin wax is typically preferred to be 40–65°C, more preferably 50–65°C.

[0363] The amount of stabilizing agent used is preferably 0.1 to 12% by mass, more preferably 0.1 to 8% by mass, based on the mass of the aqueous medium used. The stabilizing agent is preferably sufficiently hydrophobic and completely separates from the PTFE dispersion after PTFE polymerization without becoming a contaminating component.

[0364] In the manufacturing method of the present invention, polymerization is carried out as follows: an aqueous medium, the polymer (1) described above, monomers, and other additives, if necessary, are added to a polymerization reactor; the contents of the reactor are stirred; the reactor is maintained at a predetermined polymerization temperature; and then a predetermined amount of polymerization initiator is added to initiate the polymerization reaction, thereby carrying out polymerization. After the polymerization reaction begins, monomers, polymerization initiators, chain transfer agents, and the polymer (1) described above may be added as needed. The polymer (1) described above may be added after the polymerization reaction begins.

[0365] In the above polymerization, the polymerization temperature is typically 5–120℃ and the polymerization pressure is 0.05–10 MPaG. The polymerization temperature and pressure are appropriately determined based on the type of monomer used, the molecular weight of the target fluoropolymer, and the reaction rate.

[0366] The polymer (1) is preferably added in an amount of 0.0001 to 10% by mass relative to 100% by mass of the aqueous medium, based on the total amount added. A more preferred lower limit is 0.001% by mass, and a more preferred upper limit is 1% by mass. If the amount added is less than 0.0001% by mass, the dispersing power may be insufficient; if it is greater than 10% by mass, the effect will not be commensurate with the amount added, and may instead cause a decrease in the polymerization rate or cessation of the reaction. The amount of the above-mentioned compound added is appropriately determined according to the type of monomer used, the molecular weight of the target fluoropolymer, etc.

[0367] The method for manufacturing the fluoropolymer of the present invention preferably further includes a step of continuously adding the polymer (1). Continuously adding the polymer (1) means, for example, adding the polymer (1) over time and without interruption or in batches, not all at once. The polymer (1) may be added in the form of an aqueous solution containing the polymer (1) and water.

[0368] In the method for manufacturing the fluoropolymer of the present invention, the step of continuously adding the polymer (1) is preferably to begin adding the polymer (1) to the aqueous medium when the solid content of the fluoropolymer formed in the aqueous medium is 0.5% by mass or less. More preferably, the polymer (1) is added when the solid content is 0.3% by mass or less, even more preferably when the solid content is 0.2% by mass or less, and even more preferably when the solid content is 0.1% by mass or less. Particularly preferably, the addition is started simultaneously with the start of polymerization. The solid content is the concentration relative to the total concentration of the aqueous medium and the fluoropolymer.

[0369] In the process of continuously adding the above polymer (1), the amount of polymer (1) added is preferably 0.0001 to 10% by mass relative to 100% by mass of the aqueous medium. The preferred lower limit is 0.001% by mass, more preferably 0.01% by mass, and even more preferably 0.1% by mass. The preferred upper limit is 10% by mass, more preferably 1.0% by mass, and even more preferably 0.50% by mass. If the amount is less than 0.0001% by mass, the dispersing power may be insufficient; if the amount is greater than 10% by mass, the effect commensurate with the added amount will not be obtained, and it may instead cause a decrease in the polymerization rate or cessation of the reaction. The amount of the above compound added is appropriately determined according to the type of monomer used, the molecular weight of the target fluoropolymer, etc.

[0370] As for the polymerization initiator described above, there are no particular limitations as long as free radicals can be generated within the aforementioned polymerization temperature range; known oil-soluble and / or water-soluble polymerization initiators can be used. Furthermore, it can be combined with reducing agents to initiate polymerization in a redox manner. The concentration of the polymerization initiator is appropriately determined based on the type of monomer, the molecular weight of the target fluoropolymer, and the reaction rate.

[0371] Oil-soluble free radical polymerization initiators or water-soluble free radical polymerization initiators can be used as the polymerization initiators mentioned above.

[0372] As an oil-soluble free radical polymerization initiator, it can be a known oil-soluble peroxide, such as the following peroxides as representative substances: diisopropyl peroxide, disec-butyl peroxide, and other dialkyl peroxide esters; tert-butyl peroxide, tert-butyl peroxyisobutyrate, and other peroxide esters; dialkyl peroxides such as di-tert-butyl peroxide; and bis(ω-hydro-dodecylfluoroheptanoyl) peroxide, bis(ω-hydro-tetradecylfluoroheptanoyl) peroxide, bis(ω-hydro-hexadecylfluorononanoyl) peroxide, bis(perfluorobutyryl) peroxide, bis(perfluoropentanoyl) peroxide, bis(perfluorohexanoyl) peroxide, bis(perfluoroheptanoyl) peroxide, bis(perfluorooctanoyl) peroxide, bis(perfluorooctanoyl) peroxide, etc. Oxides, di(perfluorononanoyl) peroxides, di(ω-chloro-hexafluorobutyryl) peroxides, di(ω-chloro-decafluorohexanoyl) peroxides, di(ω-chloro-tetrafluorooctanoyl) peroxides, ω-hydro-dodecanoyl-ω-hydrohexafluorononanoyl-peroxides, ω-chloro-hexafluorobutyryl-ω-chloro-decafluorohexanoyl-peroxides, ω-hydro-dodecanoyl-perfluorobutyryl-peroxides, di(dichloropentafluorobutyryl) peroxides, di(trichlorooctafluorohexanoyl) peroxides, di(tetrachloroundecanoyl) peroxides, di(pentachlorotetrafluorodecanoyl) peroxides, di(undecanoyltridodecanoyl)fluoroethoacyl) peroxides, etc., are all di[perfluoro(or fluorochloro)acyl] peroxides; etc.

[0373] As a water-soluble free radical polymerization initiator, it can be a known water-soluble peroxide, such as ammonium salts, potassium salts, sodium salts of persulfate, perboric acid, perchloric acid, superphosphoric acid, and percarbonate, as well as tert-butyl maleate peroxide and tert-butyl hydroperoxide. It can also contain reducing agents such as sulfites and sulfites, and their amount relative to the peroxide can be 0.1 to 20 times.

[0374] For example, in the case of polymerization at low temperatures below 30°C, a redox initiator consisting of an oxidant and a reducing agent is preferably used as the polymerization initiator. Examples of oxidants include persulfates, organic peroxides, potassium permanganate, manganese triacetate, and cerium ammonium nitrate. Examples of reducing agents include sulfites, bisulfites, bromates, diimides, and oxalic acid. Examples of persulfates include ammonium persulfate and potassium persulfate. Examples of sulfites include sodium sulfite and ammonium sulfite. To improve the decomposition rate of the initiator, it is also preferable to add copper or iron salts to the combination of redox initiators. Examples of copper salts include copper(II) sulfate, and examples of iron salts include ferric(II) sulfate.

[0375] Examples of redox initiators include potassium permanganate / oxalic acid, ammonium persulfate / bisulfite / ferric sulfate, manganese triacetate / oxalic acid, cerium ammonium nitrate / oxalic acid, and bromate / bisulfite, with potassium permanganate / oxalic acid being preferred. When using a redox initiator, either the oxidant or the reducing agent can be added to the polymerization reactor beforehand, followed by the addition of the other continuously or intermittently to initiate polymerization. For example, when using potassium permanganate / oxalic acid, it is preferable to add oxalic acid to the polymerization reactor and then continuously add potassium permanganate thereto.

[0376] There is no particular limitation on the amount of polymerization initiator added. It is acceptable to add an amount (e.g., a concentration of several ppm relative to water) that will not significantly reduce the polymerization rate when added once, gradually, or continuously at the beginning of polymerization. The upper limit is the range in which the heat of polymerization can be deheated from the surface of the equipment while increasing the reaction temperature. More preferably, the upper limit is the range in which the heat of polymerization can be removed from the surface of the equipment.

[0377] The aforementioned aqueous medium refers to the reaction medium that enables polymerization, which is a liquid containing water. There are no particular limitations on the aqueous medium as long as it contains water; it can contain water and non-fluorinated organic solvents such as alcohols, ethers, and ketones, and / or fluorinated organic solvents with a boiling point below 40°C.

[0378] In the above polymerization process, known chain transfer agents, free radical scavengers, and decomposition agents can be added to adjust the polymerization rate and molecular weight, depending on the purpose.

[0379] Examples of chain transfer agents include esters such as dimethyl malonate, diethyl malonate, methyl acetate, ethyl acetate, butyl acetate, and dimethyl succinate, as well as isopentane, methane, ethane, propane, methanol, ethanol, isopropanol, acetone, various thiols, carbon tetrachloride, and various halogenated hydrocarbons, cyclohexane, etc.

[0380] Bromine or iodine compounds can be used as chain transfer agents. Examples of polymerization methods using bromine or iodine compounds include, for instance, the polymerization of fluorinated monomers in an aqueous medium under substantially oxygen-free conditions in the presence of bromine or iodine compounds (iodine transfer polymerization). Representative examples of the bromine or iodine compounds used include, for example, those with the general formula:

[0381] R a I x Br y

[0382] (In the formula, x and y are integers from 0 to 2 and satisfy 1≤x+y≤2, R) a It is a saturated or unsaturated fluorocarbon or chlorofluorocarbon group with 1 to 16 carbon atoms, or a hydrocarbon group with 1 to 3 carbon atoms. a Compounds (with or without oxygen atoms). Iodine or bromine is introduced into the polymer using bromine or iodine compounds, acting as crosslinking points.

[0383] Examples of iodine compounds include, for instance, 1,3-diiodoperfluoropropane, 2-iodoperfluoropropane, 1,3-diiodo-2-chloroperfluoropropane, 1,4-diiodoperfluorobutane, 1,5-diiodo-2,4-dichloroperfluoropentane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1,12-diiodoperfluorododecane, 1,16-diiodoperfluorohexadecane, diiodomethane, 1,2-diiodoethane, 1,3-diiodopropane, CF₂Br₂, BrCF₂CF₂Br, CF₃CFBrCF₂Br, CFClBr₂, and BrC. F2CFClBr, CFBrClCFClBr, BrCF2CF2CF2Br, BrCF2CFBrOCF3, 1-bromo-2-iodoperfluoroethane, 1-bromo-3-iodoperfluoropropane, 1-bromo-4-iodoperfluorobutane, 2-bromo-3-iodoperfluorobutane, 3-bromo-4-iodoperfluoro-1-butene, 2-bromo-4-iodoperfluoro-1-butene, monoiodomonobromine substituted derivatives of benzene, diiodomonobromine substituted derivatives, and (2-iodoethyl) and (2-bromoethyl) substituted derivatives, etc., these compounds can be used alone or in combination with each other.

[0384] Among these, 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane, and 2-iodoperfluoropropane are preferred in terms of polymerization reactivity, crosslinking reactivity, and ease of acquisition.

[0385] The amount of the chain transfer agent used is typically 1 to 50,000 ppm, preferably 1 to 20,000 ppm, relative to the total amount of fluorinated monomers supplied.

[0386] The chain transfer agent described above can be added to the reaction vessel all at once before polymerization begins, all at once after polymerization begins, added in several installments during polymerization, or added continuously during polymerization.

[0387] The manufacturing method of the present invention preferably further includes a step of adding a polymerization terminator (free radical scavenger) (hereinafter also referred to as the "polymerization terminator addition step"). The above-mentioned polymerization terminator addition step is performed in the above-mentioned polymerization step.

[0388] As polymerization terminators, compounds that add to free radicals within the polymerization system or do not have the ability to re-initiate after chain transfer are used. Specifically, compounds with the following functions are used: readily undergoing chain transfer reactions with primary or growth radicals to generate stable radicals that do not react with monomers; or readily undergoing addition reactions with primary or growth radicals to generate stable radicals.

[0389] The activity of a substance commonly referred to as a chain transfer agent is characterized by its chain transfer constant and re-initiation efficiency. Among chain transfer agents, a substance with a re-initiation efficiency of essentially 0% is called a polymerization terminator. As the polymerization terminator described above in this invention, preferably, for example, at least one selected from the group consisting of aromatic hydroxyl compounds, aromatic amines, N,N-diethylhydroxylamine, quinone compounds, terpenes, thiocyanates, and copper chloride (CuCl2).

[0390] Examples of aromatic hydroxyl compounds include non-substituted phenols, polyphenols, salicylic acid, m- or para-salicylic acid, gallic acid, and naphthol. Examples of non-substituted phenols include o-nitrophenol, m- or para-nitrophenol, o-aminophenol, m- or para-aminophenol, and para-nitrosophenol. Examples of polyphenols include catechol, resorcinol, hydroquinone, pyrogallol, pyrogallol, and naphthol-resorcinol.

[0391] Examples of aromatic amines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, and benzidine.

[0392] Examples of the aforementioned quinone compounds include hydroquinone, ortho-benzoquinone, meta-benzoquinone or para-benzoquinone, 1,4-naphthoquinone, alizarin, etc.

[0393] Examples of thiocyanates include ammonium thiocyanate (NH4SCN), potassium thiocyanate (KSCN), and sodium thiocyanate (NaSCN).

[0394] As the polymerization terminator mentioned above, quinone compounds are preferred, and hydroquinone is more preferred.

[0395] From the perspective of reducing the standard proportion, the above-mentioned polymerization terminator is preferably added before the polymerization of 90% by mass of the perfluoroethylene consumed in the polymerization reaction. More preferably, it is added before the polymerization of 85% by mass of the perfluoroethylene, and even more preferably, it is added before the polymerization of 80% by mass of the perfluoroethylene.

[0396] Furthermore, it is preferable to add 5% by mass of the perfluorinated monomer consumed in the polymerization reaction after polymerization, and more preferably to add 10% by mass after polymerization.

[0397] The amount of the polymerization terminator added is preferably 0.1 to 20 ppm of the mass of the aqueous medium used, and more preferably 3 to 10 ppm.

[0398] The manufacturing method of the present invention preferably further includes a step of adding a decomposing agent to an aqueous medium. By adding a decomposing agent, the concentration of free radicals in the polymerization can be adjusted. Examples of decomposing agents include sulfites, bisulfites, bromates, diimides, oxalic acid, copper salts, and iron salts. Examples of sulfites include sodium sulfite and ammonium sulfite. Examples of copper salts include copper(II), and examples of iron salts include ferric(II) sulfate.

[0399] The amount of the above-mentioned decomposing agent added is in the range of 25 to 300% by mass, relative to the amount of oxidant incorporated as a polymerization initiator (e.g., a redox initiator). Preferably, it is 25 to 150% by mass, more preferably 50 to 100% by mass.

[0400] Furthermore, it is preferable to add 5% by mass of the perfluoroethylene consumed in the polymerization reaction after polymerization, and more preferably to add 10% by mass after polymerization.

[0401] The amount of the polymerization terminator added is preferably 0.1 to 20 ppm of the mass of the aqueous medium used, and more preferably 3 to 10 ppm.

[0402] The manufacturing method of the present invention preferably involves polymerizing fluorinated monomers in the substantially non-existent presence of fluorinated surfactants.

[0403] In the past, fluorinated surfactants were used in the polymerization of fluorinated polymers, but the manufacturing method of the present invention can obtain fluorinated polymers even without the use of fluorinated surfactants by using the above-mentioned polymer (1).

[0404] In this specification, "in the substantially non-existent state of the fluorinated surfactant" means that the fluorinated surfactant relative to the aqueous medium is 10 ppm or less, preferably 1 ppm or less, more preferably 100 ppb or less, even more preferably 10 ppb or less, and even more preferably 1 ppb or less.

[0405] Examples of fluorinated surfactants include anionic fluorinated surfactants.

[0406] The aforementioned anionic fluorinated surfactants can be, for example, surfactants containing fluorine atoms in which the total number of carbon atoms in the portion excluding the anionic groups is 20 or less.

[0407] Alternatively, the aforementioned fluorinated surfactant may also be a fluorinated surfactant with an anionic moiety having a molecular weight of 800 or less.

[0408] It should be noted that the "anionic portion" mentioned above refers to the portion of the fluorinated surfactant other than the cationic portion. For example, in F(CF2) shown in formula (I) described later. n1 In the case of COOM, it is "F(CF2)". n1 The "COO" part.

[0409] Furthermore, examples of fluorinated surfactants mentioned above include those with a LogPOW of 3.5 or less. LogPOW is the partition coefficient between 1-octanol and water, expressed as LogP [where P represents the ratio of the concentration of the fluorinated surfactant in octanol to the concentration of the fluorinated surfactant in water during phase separation in an octanol / water (1:1) mixture containing the fluorinated surfactant].

[0410] The above LogPOW is calculated as follows: In column: TOSOH ODS-120T column ( Under the following conditions (manufactured by Tosoh Corporation), eluent: acetonitrile / 0.6% HClO4 water = 1 / 1 (vol / vol%), flow rate: 1.0 ml / min, sample volume: 300 μL, column temperature: 40 °C, detection light: UV210 nm, HPLC was performed on standard substances (heptanoic acid, octanoic acid, nonanoic acid, and decanoic acid) with known octanol / water partition coefficients. Calibration curves of each elution time and the known octanol / water partition coefficient were prepared. Based on the calibration curves, the elution time of the sample solution in the HPLC was calculated.

[0411] Specifically, examples of the aforementioned fluorinated surfactants include U.S. Patent Application Publication No. 2007 / 0015864, U.S. Patent Application Publication No. 2007 / 0015865, U.S. Patent Application Publication No. 2007 / 0015866, U.S. Patent Application Publication No. 2007 / 0276103, U.S. Patent Application Publication No. 2007 / 0117914, U.S. Patent Application Publication No. 2007 / 0142541, U.S. Patent Application Publication No. 2008 / 0015319, and U.S. Patent No. 3250808. Fluorinated surfactants described in patent applications, U.S. Patent No. 3,271,341, Japanese Patent Application Publication No. 2003-119204, International Publication No. 2005 / 042593, International Publication No. 2008 / 060461, International Publication No. 2007 / 046377, International Publication No. 2007 / 119526, International Publication No. 2007 / 046482, International Publication No. 2007 / 046345, U.S. Patent Application Publication No. 2014 / 0228531, International Publication No. 2013 / 189824, and International Publication No. 2013 / 189826.

[0412] Examples of anionic fluorinated surfactants include those with the following general formula (N 0 ):

[0413] X n0 -Rf n0 -Y 0 (N 0 )

[0414] (where X) n0 For H, Cl, or F. Rf n0 It is a chain, branched, or cyclic alkylene group with 3 to 20 carbon atoms, in which some or all of the H atoms are replaced by F. This alkylene group may contain more than one ether bond, and some of the H atoms may be replaced by Cl. 0 The compound shown is an anionic group.

[0415] Y 0 The anionic group can be -COOM, -SO2M or -SO3M, or it can be -COOM or -SO3M.

[0416] M represents H, a metal atom, and NR. 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is H or an organic group.

[0417] Examples of metal atoms mentioned above include alkali metals (Group 1) and alkaline earth metals (Group 2), such as Na, K, or Li.

[0418] As R 7 It can be H or C 1-10 The organic group can also be H or C. 1-4 The organic groups can also be H or C. 1-4 Alkyl groups.

[0419] M can be H, a metal atom, or NR. 7 4, can also be H, alkali metals (Group 1), alkaline earth metals (Group 2), or NR. 7 4. It can also be H, Na, K, Li or NH4.

[0420] The above Rf n0 In this process, more than 50% of H can be replaced by fluorine.

[0421] As the above general formula (N) 0 Examples of compounds shown in the diagram include:

[0422] The following general formula (N) 1 ):

[0423] X n0 -(CF2) m1 -Y 0 (N 1 )

[0424] (where X) n0 H, Cl, and F are given, m1 is an integer from 3 to 15, and Y is given. 0 Compounds represented by the substances defined above; compounds of the following general formula (N 2 ):

[0425] Rf n1 -O-(CF(CF3)CF2O) m2 CFX n1 -Y 0 (N 2 )

[0426] (where Rf) n1 It is a perfluoroalkyl group with 1 to 5 carbon atoms, m2 is an integer from 0 to 3, X n1 For F or CF3, Y 0 Compounds represented by the substances defined above; compounds of the following general formula (N 3 ):

[0427] Rf n2 (CH2) m3 -(Rf n3 ) q -Y0 (N 3 )

[0428] (where Rf) n2 It is an alkyl group with 1 to 13 carbon atoms, which may contain ether bonds or be partially or fully fluorinated, m3 is an integer from 1 to 3, and Rf n3 It is a straight-chain or branched perfluoroalkylene group with 1 to 3 carbon atoms, where q is 0 or 1, and Y is... 0 Compounds represented by the substances defined above; compounds of the following general formula (N 4 ):

[0429] Rf n4 -O-(CY n1 Y n2 ) p CF2-Y 0 (N 4 )

[0430] (where Rf) n4 Y is a straight-chain or branched partially or fully fluorinated alkyl group with 1 to 12 carbon atoms, which may contain ether bonds. n1 and Y n2 Same or different, H or F, p is 0 or 1, Y 0 Compounds of the above-defined substance; and compounds of the general formula (N 5 ):

[0431] [Chemistry 18]

[0432]

[0433] (where X) n2 X n3 and X n4 They can be the same or different, and can be H, F, or a straight-chain or branched partially or fully fluorinated alkyl group having 1 to 6 carbon atoms and containing ether bonds. Rf n5 It is a linear or branched partially or fully fluorinated alkylene group with 1 to 3 carbon atoms, which may contain ether bonds, where L is a linking group and Y is a linking group. 0 The substance is defined above. Where X is... n2 X n3 X n4 and Rf n5 The compound shown has a total number of carbon atoms of 18 or less.

[0434] As the above general formula (N) 0The compounds shown in the formula (I) are, more specifically, perfluorocarboxylic acids (I) represented by general formula (II), ω-H perfluorocarboxylic acids (II) represented by general formula (III), perfluoropolyether carboxylic acids (III) represented by general formula (III), perfluoroalkylalkylene carboxylic acids (IV) represented by general formula (IV), perfluoroalkoxyfluorocarboxylic acids (V) represented by general formula (V), perfluoroalkylsulfonic acids (VI) represented by general formula (VI), ω-H perfluorosulfonic acids (VII) represented by general formula (VII), perfluoroalkylalkylene sulfonic acids (VIII) represented by general formula (VIII), alkylalkylene carboxylic acids (IX) represented by general formula (IX), fluorocarboxylic acids (X) represented by general formula (X), alkoxyfluorosulfonic acids (XI) represented by general formula (XI), and compounds represented by general formula (XII).

[0435] The above-mentioned perfluorocarboxylic acid (I) is derived from the following general formula (I).

[0436] F(CF2) n1 COOM(I)

[0437] (In the formula, n1 is an integer from 3 to 14, M is H, metal atom, NR) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is represented by H or an organic group.

[0438] The above-mentioned ω-H perfluorocarboxylic acid (II) is derived from the following general formula (II).

[0439] H(CF2) n2 COOM(II)

[0440] (where n2 is an integer from 4 to 15, and M is the substance defined above.)

[0441] The above-mentioned perfluoropolyether carboxylic acid (III) is derived from the following general formula (III).

[0442] Rf 1 -O-(CF(CF3)CF2O) n3 CF(CF3)COOM(III)

[0443] (where Rf) 1 It is represented by a perfluoroalkyl group having 1 to 5 carbon atoms, n3 being an integer from 0 to 3, and M being a substance as defined above.

[0444] The above-mentioned perfluoroalkylalkylene carboxylic acids (IV) are derived from the following general formula (IV).

[0445] Rf 2 (CH2)n4 Rf 3 COOM(IV)

[0446] (where Rf) 2 It is a perfluoroalkyl group with 1 to 5 carbon atoms, Rf 3 It is represented by a straight-chain or branched perfluoroalkylene group with 1 to 3 carbon atoms (n4 is an integer from 1 to 3, and M is a substance as defined above).

[0447] The above-mentioned alkoxyfluorocarboxylic acid (V) is derived from the following general formula (V).

[0448] Rf 4 -O-CY 1 Y 2 CF2-COOM(V)

[0449] (where Rf) 4 Y is a straight-chain or branched partially or fully fluorinated alkyl group with 1 to 12 carbon atoms, which may contain ether bonds. 1 and Y 2 The same or different (H or F, M is the substance defined above) are represented by this.

[0450] The above-mentioned perfluoroalkyl sulfonic acid (VI) is produced by the following general formula (VI).

[0451] F(CF2) n5 SO3M(VI)

[0452] (In the formula, n5 is an integer from 3 to 14, and M is the substance defined above.)

[0453] The above-mentioned ω-H perfluorosulfonic acid (VII) is derived from the following general formula (VII).

[0454] H(CF2) n6 SO3M(VII)

[0455] (In the formula, n6 is an integer from 4 to 14, and M is the substance defined above.)

[0456] The above-mentioned perfluoroalkyl alkylene sulfonic acid (VIII) is produced by the following general formula (VIII).

[0457] Rf 5 (CH2) n7 SO3M(VIII)

[0458] (where Rf) 5 It is represented by a perfluoroalkyl group having 1 to 13 carbon atoms, n7 being an integer from 1 to 3, and M being a substance as defined above.

[0459] The above-mentioned alkylalkylene carboxylic acids (IX) are derived from the following general formula (IX).

[0460] Rf 6 (CH2) n8 COOM(IX)

[0461] (where Rf) 6 It is represented by a straight-chain or branched partially or fully fluorinated alkyl group with 1 to 13 carbon atoms that may contain ether bonds, where n8 is an integer from 1 to 3 and M is a substance as defined above.

[0462] The above-mentioned fluorocarboxylic acid (X) is derived from the following general formula (X).

[0463] Rf 7 -O-Rf 8 -O-CF2-COOM(X)

[0464] (where Rf) 7 It is a linear or branched partially or fully fluorinated alkyl group with 1 to 6 carbon atoms, which may contain ether bonds, Rf 8 It is represented by a straight-chain or branched partially or fully fluorinated alkyl group having 1 to 6 carbon atoms (M being a substance as defined above).

[0465] The above-mentioned alkoxyfluorosulfonic acid (XI) is derived from the following general formula (XI).

[0466] Rf 9 -O-CY 1 Y 2 CF2-SO3M(XI)

[0467] (where Rf) 9 It is a straight-chain or branched alkyl group with 1 to 12 carbon atoms, which may contain ether bonds and may be partially or fully fluorinated with chlorine. 1 and Y 2 The same or different (H or F, M is the substance defined above) are represented by this.

[0468] The above compound (XII) is derived from the following general formula (XII):

[0469] [Chemistry 19]

[0470]

[0471] In the formula, X 1 X 2 and X 3 They can be the same or different, and are H, F, and linear or branched partially or fully fluorinated alkyl groups with 1 to 6 carbon atoms, which may contain ether bonds; Rf 10 It is a perfluoroalkylene group with 1 to 3 carbon atoms, where L is a linking group and Y is a linking group. 0 It is represented by an anionic group.

[0472] Y 0 It can be -COOM, -SO2M or -SO3M, or -SO3M or COOM (where M is the substance defined above).

[0473] Examples of L include single bonds, partially or fully fluorinated alkylene groups with 1 to 10 carbon atoms that may contain ether bonds.

[0474] As mentioned above, examples of anionic fluorinated surfactants include carboxylic acid surfactants and sulfonic acid surfactants.

[0475] The above-mentioned method for manufacturing fluoropolymers may be a method for manufacturing fluoropolymers including the following steps: step (I), polymerizing the above-mentioned fluorinated monomers in an aqueous medium in the presence of the above-mentioned polymer (1) to produce an aqueous dispersion of fluoropolymer (A) particles; and step (II), seeding the above-mentioned fluorinated monomers on the fluoropolymer (A) particles in the aqueous dispersion of the above-mentioned fluoropolymer (A) particles.

[0476] As a fluoropolymer that is suitably manufactured by the manufacturing method of the present invention, it is acceptable as long as it is different from the polymer (1) described above. Examples include a TFE polymer in which the monomer with the highest molar fraction of monomers (hereinafter referred to as "most monomer") is TFE, a VDF polymer in which the most monomer is VDF, and a CTFE polymer in which the most monomer is CTFE.

[0477] The TFE polymer can be suitably a TFE homopolymer, or a copolymer composed of the following components: (1) TFE; (2) one or more fluorinated monomers other than TFE having 2 to 8 carbon atoms, particularly VDF, HFP, or CTFE; and (3) other monomers. Examples of the other monomers mentioned in (3) include, for example, fluorinated (alkyl vinyl ethers) having 1 to 5 carbon atoms, particularly 1 to 3 carbon atoms; fluorinated m-dioxane; perfluoroalkyl ethylene; ω-hydrogenated perfluoroolefin; etc.

[0478] The TFE polymer can also be a copolymer of TFE and one or more non-fluorinated monomers. Examples of non-fluorinated monomers include olefins such as ethylene and propylene; vinyl esters; and vinyl ethers. The TFE polymer can also be a copolymer of TFE, one or more fluorinated monomers having 2 to 8 carbon atoms, and one or more non-fluorinated monomers.

[0479] As a VDF polymer, it may suitably be a VDF homopolymer [PVDF] or a copolymer composed of the following components: (1) VDF; (2) one or more fluoroolefins other than VDF having 2 to 8 carbon atoms, particularly TFE, HFP or CTFE; and (3) a perfluorinated (alkyl vinyl ether) having 1 to 5 carbon atoms, particularly 1 to 3 carbon atoms; etc.

[0480] As a CTFE polymer, it may suitably be a CTFE homopolymer or a copolymer composed of the following components: (1) CTFE; (2) one or more fluoroolefins other than CTFE having 2 to 8 carbon atoms, particularly TFE or HFP; and (3) a perfluorinated (alkyl vinyl ether) having 1 to 5 carbon atoms, particularly 1 to 3 carbon atoms.

[0481] As a CTFE polymer, it can also be a copolymer of CTFE with one or more non-fluorinated monomers. Examples of non-fluorinated monomers include olefins such as ethylene and propylene; vinyl esters; and vinyl ethers.

[0482] The fluoropolymers manufactured by the method of the present invention can be glassy, ​​plastic, or elastomeric. These substances are amorphous or partially crystalline and can be used in compression calcination, melt processing, or non-melt processing.

[0483] The manufacturing method of the present invention can be used to suitably manufacture, for example, the following substances: (I) tetrafluoroethylene polymers [TFE polymer (PTFE)] as non-melt processable fluoropolymers; (II) ethylene / TFE copolymers [ETFE], TFE / HFP copolymers [FEP], TFE / perfluoro(alkyl vinyl ether) copolymers [PFA, MFA, etc.], TFE / VDF copolymers, electrolyte polymer precursors; (III) TFE / propylene copolymers, TFE / propylene / third monomer copolymers (the third monomer being VDF, HFP, CTFE, fluoroalkyl vinyl ethers, etc.) as fluororubbers; copolymers composed of TFE and fluoroalkyl vinyl ethers; HFP / ethylene copolymers, HFP / ethylene / TFE copolymers; PVDF; VDF / HFP copolymers, HFP / ethylene copolymers, VDF / TFE / HFP copolymers, and other thermoplastic elastomers; and fluorinated segmented polymers as described in Japanese Patent Publication No. 61-49327; etc.

[0484] As the aforementioned fluoropolymer, fluoropolymers are preferred, with fluoropolymers having a fluorine substitution rate of 50% or more calculated by the following formula being more preferred, fluoropolymers having a fluorine substitution rate greater than 50% being even more preferred, fluoropolymers having a fluorine substitution rate of 55% or more being even more preferred, fluoropolymers having a fluorine substitution rate of 60% or more being even more preferred, fluoropolymers having a fluorine substitution rate of 75% or more being even more preferred, fluoropolymers having a fluorine substitution rate of 80% or more being particularly preferred, and fluoropolymers having a fluorine substitution rate of 90 to 100%, i.e., perfluorinated resins, being the most preferred type of fluoropolymer.

[0485] (Mode)

[0486] Fluorine substitution rate (%) = (Number of fluorine atoms bonded to the carbon atoms constituting the fluoropolymer) / ((Number of hydrogen atoms bonded to the carbon atoms constituting the fluoropolymer) + (Number of fluorine and chlorine atoms bonded to the carbon atoms constituting the fluoropolymer)) × 100

[0487] As the aforementioned perfluorinated resin, a fluorinated resin with a fluorine substitution rate of 95-100% is more preferred, PTFE, FEP, and PFA are even more preferred, and PTFE is particularly preferred.

[0488] The above-mentioned (I) non-melt processable fluoropolymer, (II) melt processable fluoropolymer and (III) fluororubber, which are suitably manufactured by the manufacturing method of the present invention, are preferably manufactured in the following manner.

[0489] (I) Non-melt processable fluoropolymers

[0490] In the manufacturing method of the present invention, the polymerization of TFE is generally carried out at a polymerization temperature of 10 to 150°C and a polymerization pressure of 0.05 to 5 MPaG. For example, the polymerization temperature is more preferably 30°C or higher, and even more preferably 50°C or higher. Furthermore, it is more preferably 120°C or lower, and even more preferably 100°C or lower. Furthermore, the polymerization pressure is more preferably 0.3 MPaG or higher, even more preferably 0.5 MPaG or higher, and even more preferably 5.0 MPaG or lower, and even more preferably 3.0 MPaG or lower. In particular, from the viewpoint of increasing the yield of fluoropolymer, it is preferably 1.0 MPaG or higher, more preferably 1.2 MPaG or higher, even more preferably 1.5 MPaG or higher, and even more preferably 2.0 MPaG or higher.

[0491] In one approach, regarding the above polymerization, pure water is added to a pressure-resistant reaction vessel equipped with a stirrer, deoxygenated, and then TFE is added. The mixture is brought to a predetermined temperature, and a polymerization initiator is added to initiate the reaction. As the pressure decreases with the reaction, additional TFE is supplied continuously or intermittently to maintain the initial pressure. The supply of TFE is stopped when a predetermined amount has been supplied, the TFE in the reaction vessel is purged, the temperature is restored to room temperature, and the reaction is terminated. To prevent a decrease in pressure, additional TFE can be supplied continuously or intermittently.

[0492] In the manufacture of the aforementioned TFE polymer (PTFE), various known modifying monomers may be used in combination. In this specification, the term "TFE polymer" refers not only to TFE homopolymers but also to non-melt processable substances (hereinafter referred to as "modified PTFE") that are copolymers of TFE and modifying monomers.

[0493] Examples of the aforementioned modifying monomers include: perhaloolefins such as HFP, CTFE, and perfluorovinyl ethers; fluorinated (alkyl vinyl ethers) having alkyl groups with 1 to 5 carbon atoms, particularly 1 to 3 carbon atoms; cyclic fluorinated monomers such as fluorinated m-dioxanepentene; perhaloalkyl ethylenes such as (perfluoroalkyl)ethylene; and ω-hydrogenated perhaloolefins. The supply of the modifying monomers can be carried out either initially in a single addition or continuously or intermittently in multiple additions, depending on the intended use or the supply of TFE.

[0494] As for the aforementioned perfluorovinyl ethers, there are no particular limitations; examples such as the following general formula (A) can be cited:

[0495] CF2 = CF - ORf(A)

[0496] (where Rf represents a perfluorinated organic group) This refers to perfluorinated unsaturated compounds, etc. In this specification, the term "perfluorinated organic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are replaced by fluorine atoms. The aforementioned perfluorinated organic group may contain ether oxygen.

[0497] Examples of perfluorovinyl ethers include, for instance, perfluoro(alkylvinyl ethers) [PAVE] in which Rf is a perfluoroalkyl group having 1 to 10 carbon atoms in the above general formula (A). The preferred number of carbon atoms in the perfluoroalkyl group is 1 to 5.

[0498] Examples of perfluoroalkyl groups in the aforementioned PAVE include perfluoromethyl, perfluoroethyl, perfluoropropyl, perfluorobutyl, perfluoropentyl, and perfluorohexyl.

[0499] Examples of perfluorovinyl ethers include substances in which Rf in the above general formula (A) is a perfluoro(alkoxyalkyl) compound with 4 to 9 carbon atoms; or substances with the following formula:

[0500] [Chemistry 20]

[0501]

[0502] (where m represents 0 or an integer from 1 to 4) represents the substance with the indicated group; Rf is the following formula:

[0503] [Chemistry 21]

[0504]

[0505] Substances containing groups such as (where n represents an integer from 1 to 4).

[0506] There is no particular limitation on (perfluoroalkyl)ethylene (PFAE), and examples include (perfluorobutyl)ethylene (PFBE) and (perfluorohexyl)ethylene.

[0507] As the modified monomers mentioned above, comonomers (3) with a monomer reactivity ratio of 0.1 to 8 are also preferred examples. With the presence of comonomers (3), modified PTFE particles with small particle size can be obtained, and aqueous dispersions with high dispersion stability can be obtained.

[0508] Here, the monomer reactivity ratio in the copolymerization with TFE is obtained as follows: when the number of growth radicals is less than the number of repeating units based on TFE, the rate constant of the reaction between the growth radical and TFE is divided by the rate constant of the reaction between the growth radical and the comonomer. The resulting value is the monomer reactivity ratio. The lower this value, the higher the reactivity of the comonomer with TFE. The monomer reactivity ratio can be calculated as follows: copolymerize TFE with the comonomer, determine the composition of the initially formed polymer, and calculate using the Fineman-Ross formula.

[0509] The copolymerization was carried out in a 6.0L stainless steel autoclave using 3600g of deionized degassed water, 1000ppm of ammonium perfluorooctanoate relative to the water, and 100g of paraffin wax at a pressure of 0.78MPa and a temperature of 70°C. Comonomers of 0.05g, 0.1g, 0.2g, 0.5g, and 1.0g were added to the reactor, along with 0.072g of ammonium persulfate (20ppm relative to water). To maintain a polymerization pressure of 0.78MPa, TFE was continuously supplied. After 1000g of TFE was added, stirring was stopped, and depressurization was performed until the reactor reached atmospheric pressure. After cooling, the paraffin wax was separated, yielding an aqueous dispersion containing the polymer. The aqueous dispersion was stirred to precipitate the polymer, which was then dried at 150°C. The composition of the resulting polymer was calculated by appropriately combining NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis based on the monomer type.

[0510] The comonomer (3) having a monomer reactivity ratio of 0.1 to 8 is preferably at least one of the group consisting of comonomers represented by free formulas (3a) to (3d).

[0511] CH2=CH-Rf 1 (3a)

[0512] (where Rf) 1 It is a perfluoroalkyl group with 1 to 10 carbon atoms.

[0513] CF2 = CF-O-Rf 2 (3b)

[0514] (where Rf) 2 It is a perfluoroalkyl group having 1 to 2 carbon atoms.

[0515] CF2 = CF - O - (CF2) n CF = CF2(3c)

[0516] (In the formula, n is 1 or 2.)

[0517] [Chemistry 22]

[0518]

[0519] (where X) 3 and X 4 (The atom is F, Cl, or methoxy, and Y is of formula Y1 or Y2.)

[0520] [Chemistry 23]

[0521] -CF=CF- (Y1)

[0522]

[0523] (In formula Y2, Z and Z' are F or fluoroalkyl groups with 1 to 3 carbon atoms.)

[0524] The content of comonomer (3) relative to the modified PTFE is preferably in the range of 0.00001 to 1.0% by mass. As a lower limit, it is more preferably 0.0001% by mass, further preferably 0.001% by mass, even more preferably 0.005% by mass, and particularly preferably 0.009% by mass. As an upper limit, it is more preferably 0.50% by mass, further preferably 0.40% by mass, even more preferably 0.30% by mass, particularly preferably 0.10% by mass, and particularly preferably 0.05% by mass.

[0525] As the modified monomers described above, since an aqueous dispersion with small average primary particle size, small aspect ratio, and excellent stability of polytetrafluoroethylene particles can be obtained, it is preferable to select at least one from the group consisting of hexafluoropropylene, vinylidene fluoride, fluorinated (alkyl vinyl ether), (perfluoroalkyl) ethylene, ethylene, and modified monomers having functional groups and hydrophilic groups capable of undergoing free radical polymerization.

[0526] From the perspective of reactivity with TFE, the modified monomers mentioned above preferably include at least one selected from the group consisting of hexafluoropropylene, perfluoro(alkyl vinyl ether) and (perfluoroalkyl)ethylene.

[0527] More preferably, it comprises at least one selected from the group consisting of hexafluoropropylene, perfluoro(methyl vinyl ether), perfluoro(propyl vinyl ether), (perfluorobutyl)ethylene, (perfluorohexyl)ethylene and (perfluorooctyl)ethylene.

[0528] The total amount of the aforementioned hexafluoropropylene unit, perfluoro(alkyl vinyl ether) unit, and (perfluoroalkyl)ethylene unit is preferably in the range of 0.00001 to 1.0% by mass relative to the modified PTFE. As a lower limit of the above total amount, it is more preferably 0.001% by mass, further preferably 0.005% by mass, and particularly preferably 0.009% by mass. As an upper limit, it is more preferably 0.50% by mass, further preferably 0.40% by mass, even more preferably 0.30% by mass, particularly preferably 0.10% by mass, and especially preferably 0.05% by mass.

[0529] In the manufacturing method of the present invention, a modified monomer (hereinafter referred to as "modified monomer (A)") having functional groups and hydrophilic groups capable of undergoing free radical polymerization can also be used in conjunction with the above-mentioned surfactant. As the modified monomer (A), any compound containing at least one vinyl group and possessing surface-active capabilities is acceptable. Examples of hydrophilic groups in the modified monomer (A) include, for example, -NH2, -PO3M, -OPO3M, -SO3M, -OSO3M, and -COOM (where M is H, a metal atom, or NR). 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It can be an H or an organic group, which can be the same or different. Any two can bond together to form a ring. As the above-mentioned hydrophilic group, -SO3M or -COOM is preferred. As R 7 H or C are preferred 1-10 Organic groups, more preferably H or C 1-4 The organic groups, preferably H or C, are preferred. 1-4 Alkyl groups.

[0530] Examples of metal atoms that can be classified as monovalent or divalent include alkali metals (Group 1) and alkaline earth metals (Group 2), with Na, K, or Li being preferred.

[0531] As a "functional group capable of undergoing free radical polymerization" in the aforementioned modified monomer (A), examples include groups having olefinic unsaturated bonds. Examples of groups having olefinic unsaturated bonds include R (described later). a Linking groups, preferably, include groups with unsaturated bonds such as -CH=CH2, -CF=CH2, -CH=CF2, -CF=CF2, -CH2-CH=CH2, -CF2-CF=CH2, -CF2-CF=CF2, -(C=O)-CH=CH2, -(C=O)-CF=CH2, -(C=O)-CH=CF2, -(C=O)-CF=CF2, -(C=O)-C(CH3)=CH2, -(C=O)-C(CF3)=CH2, -(C=O)-C(CH3)=CF2, -(C=O)-C(CF3)=CF2, -O-CH2-CH=CH2, -O-CF2-CF=CH2, -O-CH2-CH=CF2, -O-CF2-CF=CF2, and -O-CF2-CF=CF2.

[0532] The preferred general formula for the modified monomer (A) is (4):

[0533] CX i X k =CX j R a -(CZ 1 Z 2 ) k -Y 3 (4)

[0534] (where X) i X j and X k Each is independently F, Cl, H or CF3; Y 3 R is a hydrophilic group; a Z is a linking group; 1 and Z 2 The compounds are each independently H, F or CF3, and k is 0 or 1.

[0535] Examples of hydrophilic groups mentioned above include -NH2, -PO3M, -OPO3M, -SO3M, -OSO3M, and -COOM (where M represents H, a metal atom, or NR). 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7It can be an H or an organic group, which can be the same or different. Any two can bond together to form a ring. As the above-mentioned hydrophilic group, -SO3M or -COOM is preferred. As R 7 H or C are preferred 1-10 Organic groups, more preferably H or C 1-4 The organic groups, preferably H or C, are preferred. 1-4 Alkyl groups.

[0536] Examples of metal atoms that can be classified as monovalent or divalent include alkali metals (Group 1) and alkaline earth metals (Group 2), with Na, K, or Li being preferred.

[0537] By using the modified monomer (A) described above, an aqueous dispersion with a smaller average primary particle size and superior stability can be obtained. Furthermore, the aspect ratio of the primary particles can be further reduced.

[0538] The above R a The linking group is a divalent linking group. In this specification, "linking group" refers to a divalent linking group. The linking group can be a single bond, preferably containing at least one carbon atom. The number of carbon atoms can be 2 or more, 4 or more, 8 or more, 10 or more, or 20 or more. There is no upper limit; for example, it can be less than 100 or less than 50.

[0539] The linking group described above may be chain-like or branched, cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and may contain one or more heteroatoms selected from the group consisting of sulfur, oxygen, and nitrogen, and may contain one or more functional groups selected from the group consisting of esters, amides, sulfonamides, carbonyl groups, carbonates, carbamates, ureas, and carbamates. The linking group described above does not contain carbon atoms and may be chain-like heteroatoms such as oxygen, sulfur, or nitrogen.

[0540] The above R a Preferably, it consists of chain heteroatoms such as oxygen, sulfur, and nitrogen, or divalent organic groups.

[0541] R a In the case of a divalent organic group, the hydrogen atom bonded to the carbon atom can be replaced by a halogen other than fluorine, such as chlorine, and may or may not contain a double bond. Additionally, R... a It can be either chain-like or branched, or cyclic or acyclic. Additionally, R... a It may contain functional groups (such as esters, ethers, ketones, amines, halides, etc.).

[0542] Additionally, R a It can be a non-fluorinated divalent organic group, or a partially fluorinated or perfluorinated divalent organic group.

[0543] As R a For example, a hydrocarbon group with no fluorine atom bonded to the carbon atom; a hydrocarbon group with some of the hydrogen atoms bonded to the carbon atom replaced by fluorine atoms; a hydrocarbon group with all the hydrogen atoms bonded to the carbon atom replaced by fluorine atoms; a hydrocarbon group containing -(C=O)-, -(C=O)-O-, or -(C=O)-, which may contain oxygen atoms, double bonds, or functional groups.

[0544] R a Preferably, it is a hydrocarbon group with 1 to 100 carbon atoms, containing or not containing -(C=O)-, -(C=O)-O- or ether bonds, and containing or not containing a carbonyl group, wherein some or all of the hydrogen atoms bonded to the carbon atoms in the hydrocarbon group can be replaced by fluorine.

[0545] As R a Preferably selected from -(CH2) a -、-(CF2) a -、-O-(CF2) a -、-(CF2) a -O-(CF2) b -、-O(CF2) a -O-(CF2) b -、-(CF2) a -[O-(CF2) b ] c -、-O(CF2) a -[O-(CF2) b ] c -、-[(CF2) a -O] b -[(CF2) c -O] d -、-O[(CF2) a -O] b -[(CF2) c -O] d -、-O-[CF2CF(CF3)O] a -(CF2) b -, -(C=O)-, -(C=O)-O-, -(C=O)-(CH2) a -、-(C=O)-(CF2) a -、-(C=O)-O-(CH2) a -、-(C=O)-O-(CF2) a -、-(C=O)-[(CH2) a -O] b -、-(C=O)-[(CF2) a -O] b-、-(C=O)-O[(CH2) a -O] b -、-(C=O)-O[(CF2) a -O] b -、-(C=O)-O[(CH2) a -O] b -(CH2) c -、-(C=O)-O[(CF2) a -O] b -(CF2) c -、-(C=O)-(CH2) a -O-(CH2) b -、-(C=O)-(CF2) a -O-(CF2) b -、-(C=O)-O-(CH2) a -O-(CH2) b -、-(C=O)-O-(CF2) a -O-(CF2) b -, -(C=O)-O-C6H4- and at least one of their combinations.

[0546] In the formula, a, b, c, and d are each at least 1. a, b, c, and d can each be 2 or higher, 3 or higher, 4 or higher, 10 or higher, or 20 or higher. The upper limit for a, b, c, and d is, for example, 100.

[0547] As R a Preferred specific examples include -CF2-O-, -CF2-O-CF2-, -CF2-O-CH2-, -CF2-O-CH2CF2-, -CF2-O-CF2CF2-, -CF2-O-CF2CH2-, -CF2-O-CF2CF2CH2-, -CF2-O-CF2CF2CH2-, -CF2-O-CF(CF3)-, -CF2-O-CF(CF3)CF2-, -CF2-O-CF(CF3)CF2-O-, -CF2-O-CF(CF3)CH2-, -(C=O)-, -(C=O)-O-, -(C=O)-(CH2)-, -(C=O)-(CF2)-, -(C=O)-O-(CH2)-, -(C=O)-O-(CF2)-, and -(C=O)-[(CH2)2-O] n -、-(C=O)-[(CF2)2-O] n -、-(C=O)-O[(CH2)2-O] n -、-(C=O)-O[(CF2)2-O] n-、-(C=O)-O[(CH2)2-O] n -(CH2)-, -(C=O)-O[(CF2)2-O] n -(CF2)-, -(C=O)-(CH2)2-O-(CH2)-, -(C=O)-(CF2)2-O-(CF2)-, -(C=O)-O-(CH2)2-O-(CH2)-, -(C=O)-O-(CF2)2-O-(CF2)-, -(C=O)-O-C6H4-, etc. Specifically, the above R... a Preferably -CF2-O-, -CF2-O-CF2-, -CF2-O-CF2CF2-, -CF2-O-CF(CF3)-, -CF2-O-CF(CF3)CF2-, -CF2-O- CF(CF3)CF2-O-, -(C=O)-, -(C=O)-O-, -(C=O)-(CH2)-, -(C=O)-O-(CH2)-, -(C=O)-O[(CH2)2-O] n -、-(C=O)-O[(CH2)2-O] n -(CH2)-, -(C=O)-(CH2)2-O-(CH2)-, or -(C=O)-O-C6H4-.

[0548] In the above formula, n is an integer from 1 to 10.

[0549] As in the above general formula (4) -R a -(CZ 1 Z 2 ) k, preferably -CF2-O-CF2-, -CF2-O-CF(CF3)-, -CF2-O-C(CF3)2-, -CF2-O-CF2-CF2-, -CF2-O-CF2-CF(CF3)-, -CF2-O-CF2-C(CF3)2-, -CF2-O-CF2CF2-CF2-, -CF2-O-CF2CF2-CF(CF3)-, -CF2-O-CF2CF2-C(CF3)2-, -CF2-O-CF(CF3)-CF2-, -CF2-O-CF(CF3)-CF(CF3)-, -CF2-O-CF(CF3)-C(CF3)2-, -CF2-O-CF(CF3)-CF2-, -CF2-O-CF(CF3)-CF(CF3)-, -CF2-O-CF(CF3)-C(CF3)2-, -CF2-O-CF(CF3)CF2-CF2-, -CF2-O-CF(CF3)CF2-CF(CF3)-, -CF2-O-CF(CF3)CF2-C(CF3)2-, -CF2-O-CF(CF3)CF2-O-CF2-, -CF2-O-CF(CF3)CF2-O-CF(CF3)-, -CF2-O-CF(CF3)CF2-O-C(CF3)2-, -(C=O)-, -(C=O)-O-, -(C=O)-(CH2)-, -(C=O)-(CF2)-, -(C=O)-O-(CH2)-, -(C=O)-O-(CF2)-, -(C=O)-[(CH2)2-O] n -(CH2)-, -(C=O)-[(CF2)2-O] n -(CF2)- , -(C=O)-[(CH2)2-O] n -(CH2)-(CH2)- ,-(C=O)-[(CF2)2-O] n -(CF2)-(CF2)- , -(C=O)-O[(CH2)2-O] n -(CF2)- ,-(C=O)-O[(CH2)2-O] n -(CH2)-(CH2)- , -(C=O)-O[(CF2)2-O] n -(CF2)- ,-(C=O)-O[(CF2)2-O] n-(CF2)-(CF2)- , -(C=O)-(CH2)2-O-(CH2)-(CH2)- , -(C=O)-(CF2)2-O-(CF2)-(CF2)- , -(C=O)-O-(CH2)2-O-(CH2)-(CH2)- , -(C=O)-O-(CF2)2-O-(CF2)-(CF2)-, -(C=O)-O-(CH2)2-O-(CH2)-C(CF3)2-, -(C=O)-O-(CF2)2-O -(CF2)-C(CF3)2-, or -(C=O)-O-C6H4-C(CF3)2-, more preferably -CF2-O-CF(CF3)-, -CF2-O-CF2-CF(CF3)-, -C F2-O-CF2CF2-CF(CF3)-, -CF2-O-CF(CF3)-CF(CF3)-, -CF2-O-CF(CF3)CF2-CF(CF3)-, -CF2-O-CF( CF3)CF2-O-CF(CF3)-, -(C=O)-, -(C=O)-O-(CH2)-, -(C=O)-O-(CH2)-(CH2)-, -(C=O)-O[(CH2)2-O] n -(CH2)-(CH2)-, -(C=O)-O-(CH2)2-O-(CH2)-C(CF3)2-, or -(C=O)-O-C6H4-C(CF3)2-.

[0550] In the above formula, n is an integer from 1 to 10.

[0551] Specific examples of compounds represented by general formula (4) can be given as follows:

[0552] [Chemistry 24]

[0553]

[0554] (where X) j and Y 3 Same as above. (n is an integer from 1 to 10), etc.

[0555] As R a The following general formula (r1) is preferred:

[0556] -(C=O) h -(O) i- CF2-O-(CX 6 2) e -{O-CF(CF3)} f -(O) g -(r1)

[0557] (where X) 6Each of the divalent groups is independently H, F, or CF3, e is an integer from 0 to 3, f is an integer from 0 to 3, g is 0 or 1, h is 0 or 1, and i is 0 or 1. The following general formula (r2) is also preferred:

[0558] -(C=O) h -(O) i- CF2-O-(CX 7 2) e -(O) g -(r2)

[0559] (where X) 7 Each of the following is a divalent group, which is H, F or CF3, e is an integer from 0 to 3, g is 0 or 1, h is 0 or 1, and i is 0 or 1.

[0560] In addition, -R is the general formula (4) mentioned above. a -CZ 1 Z 2 - It is also preferable to use the following formula (t1):

[0561] -(C=O) h -(O) i- CF2-O-(CX 6 2) e -{O-CF(CF3)} f -(O) g -CZ 1 Z 2 -(t1)

[0562] (where X) 6 Each is independently H, F, or CF3, e is an integer from 0 to 3, f is an integer from 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1, Z is 0 or 1. 1 and Z 2 Each is an independent divalent group represented by F or CF3), in formula (t1), Z 1 and Z 2 One of them is F, and the other is CF3.

[0563] In addition, in the above general formula (4), -R a -CZ 1 Z 2 - It is also preferable to use the following formula (t2):

[0564] -(C=O) h -(O) i- CF2-O-(CX 7 2) e -(O) g -CZ 1 Z 2 -(t2)

[0565] (where X) 7 Each is independently H, F, or CF3, e is an integer from 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1, and Z is 0 or 1. 1 and Z 2 Each of the following is a divalent group, independently represented by H, F, or CF3, in formula (t2), Z 1 and Z 2 One of them is F, and the other is CF3.

[0566] The compounds represented by general formula (4) are also preferably provided with the addition of the hydrophilic group (Y). 3 It has CF bonds but no CH bonds, except for X. That is, in general formula (4), X is preferred. i X j and X k All are F, R a It is a perfluoroalkylene group having 1 or more carbon atoms. The perfluoroalkylene group can be either chain-like or branched, cyclic or acyclic, and can contain at least one chain heteroatom. The number of carbon atoms in the perfluoroalkylene group can be 2 to 20, or 4 to 18.

[0567] The compound represented by general formula (4) can also be partially fluorinated. That is, the compound represented by general formula (4) is preferably free of hydrophilic groups (Y). 3 It has at least one hydrogen atom bonded to a carbon atom, and at least one fluorine atom bonded to a carbon atom, in addition to the above.

[0568] The compound represented by general formula (4) is also preferably the compound represented by formula (4a) below.

[0569] CF2 = CF-O-Rf 0 -Y 3 (4a)

[0570] (where Y) 3 Rf is a hydrophilic group. 0 Perfluorinated compounds can be chain-like or branched, cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and can arbitrarily contain one or more heteroatoms selected from the group consisting of sulfur, oxygen, and nitrogen as a perfluorinated divalent linking group.

[0571] The compound represented by general formula (4) is also preferably the compound represented by formula (4b) below.

[0572] CH2=CH-O-Rf 0 -Y 3 (4b)

[0573] (where Y) 3 Rf is a hydrophilic group.0 (This refers to the perfluorinated divalent linker as defined in formula (4a).)

[0574] In general formula (4), Y 3 -OSO3M is one of the preferred methods. In Y 3 In the case of -OSO3M, as a polymerization unit based on the compound shown in general formula (4), examples include -[CF2CF(OCF2CF2CH2OSO3M)]-, -[CH2CH((CF2)4CH2OSO3M)]-, -[CF2CF(O(CF2)4CH2OSO3M)]-, -[CF2CF(OCF2CF(CF3)CH2OSO3M)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CH2OSO3M)]-, -[CH2CH((CF2)4CH2OSO3M)]-, -[CF2CF(OCF2CF2SO2N(CH3)CH2CH2OSO3M)]-, and -[CH2CH(CF2CF2CH2OSO3M)]-. =-[CF2CF(OCF2CF2CF2CF2SO2N(CH3)CH2CH2OSO3M)]-, -[CH2CH(CF2CF2CH2OSO3M)]-, etc. In the above formula, M is the same as above.

[0575] In general formula (4), Y 3 -SO3M is also one of the preferred methods. In Y 3 In the case of -SO3M, as a polymerization unit based on the compound shown in general formula (4), examples include -[CF2CF(OCF2CF2SO3M)]-, -[CF2CF(O(CF2)4SO3M)]-, -[CF2CF(OCF2CF(CF3)SO3M)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2SO3M)]-, -[CH2CH(CF2CF2SO3M)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CF2CF2SO3M)]-, -[CH2CH((CF2)4SO3M)]-, -[CH2CH(CF2CF2SO3M)]-, -[CH2CH((CF2)4SO3M)]-, etc. In the above formula, M is the same as above.

[0576] In general formula (4), Y 3 Using -COOM is also a preferred method. In Y 3In the case of -COOM, examples of polymerization units based on compounds represented by general formula (4) include -[CF2CF(OCF2CF2COOM)]-, -[CF2CF(O(CF2)5COOM)]-, -[CF2CF(OCF2CF(CF3)COOM)]-, and -[CF2CF(OCF2CF(CF3)O(CF2)]-. n COOM)]-(n is greater than 1),-[CH2CH(CF2CF2COOM)]-,-[CH2CH((CF2)4COOM)]-,-[CH2CH(CF2CF2COOM)]-,-[CH2CH((CF2)4COOM)] -, -[CF2CF(OCF2CF2SO2NR'CH2COOM)]-, -[CF2CF(O(CF2)4SO2NR'CH2COOM)]-, -[CF2CF(OCF2CF(CF3)SO2NR'CH2COOM)]- , -[CF2CF(OCF2CF(CF3)OCF2CF2SO2NR'CH2COOM)]- , -[CH2CH(CF2CF2SO2NR'CH2COOM)]- , -[CF2CF(OCF2CF(CF3)OCF2CF2CF2CF2SO2NR'CH2COOM)]- Formulas such as -[CH2CH((CF2)4SO2NR'CH2COOM)]-, -[CH2CH(CF2CF2SO2NR'CH2COOM)]-, and -[CH2CH((CF2)4SO2NR'CH2COOM)]- are used. In these formulas, R' represents H or C. 1-4 Alkyl groups, M is the same as above.

[0577] In general formula (4), Y 3 -OPO3M is also one of the preferred methods. In Y 3In the case of -OPO3M, as polymerization units based on compounds represented by general formula (4), examples include -[CF2CF(OCF2CF2CH2OP(O)(OM)2)]-, -[CF2CF(O(CF2)4CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF2SO2N(CH3)CH2CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF2CF2CF2SO2N(CH3)CH2CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF2CF2CF2SO2N(CH3)CH2CH2OP(O)(OM)2)]- =-[CH2CH(CF2CF2CH2OP(O)(OM)2)]-,-[CH2CH((CF2)4CH2OP(O)(OM)2)]-,-[CH2CH(CF2CF2CH2OP(O)(OM)2)]-,-[CH2CH((CF2)4CH2OP(O)(OM)2)]-, etc. In the above formulas, M is the same as above.

[0578] In general formula (4), Y 3 -PO3M is also one of the preferred methods. In Y 3 In the case of -PO3M, as a polymerization unit based on the compound shown in general formula (4), examples include -[CF2CF(OCF2CF2P(O)(OM)2)]-, -[CF2CF(O(CF2)4P(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)P(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2P(O)(OM)2)]-, -[CH2CH(CF2CF2P(O)(OM)2)]-, -[CH2CH((CF2)4P(O)(OM)2)]-, -[CH2CH(CF2CF2P(O)(OM)2)]-, and -[CH2CH((CF2)4P(O)(OM)2)]-, where M is the same as above.

[0579] The compound represented by the above general formula (4) is preferably at least one selected from the group consisting of the following monomers, which are of the following general formula (5):

[0580] CX2=CY(-CZ2-O-Rf-Y 3 (5)

[0581] (In the formula, X may be the same or different and is -H or -F; Y may be -H, -F, alkyl or fluoroalkyl; Z may be the same or different and is -H, -F, alkyl or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms, or a fluoroalkylene group with ether bonds with 2 to 100 carbon atoms. Y) 3 Same as above). The monomer shown; the following general formula (6):

[0582] CX2=CY(-O-Rf-Y 3 (6)

[0583] (In the formula, X may be the same or different, and can be -H or -F; Y can be -H, -F, alkyl or fluorinated alkyl; Rf is a fluorinated alkylene with 1 to 40 carbon atoms, or a fluorinated alkylene with ether bonds having 2 to 100 carbon atoms. Y) 3 The same monomers as those described above; and the following general formula (7):

[0584] CX2 = CY(-Rf-Y) 3 (7)

[0585] (In the formula, X may be the same or different, and can be -H or -F; Y can be -H, -F, alkyl or fluorinated alkyl; Rf is a fluorinated alkylene with 1 to 40 carbon atoms, or a fluorinated alkylene with ether bonds having 2 to 100 carbon atoms. Y) 3 The same monomers as described above.

[0586] In the above general formula (5), X is -H or -F. X can be both -H, both -F, or at least one -H. For example, one can be -F and the other -H, or both -H.

[0587] In the above general formula (5), Y is -H, -F, alkyl or fluorinated alkyl.

[0588] The alkyl group described above is an alkyl group that does not contain fluorine atoms and has 1 or more carbon atoms. Preferably, the alkyl group has 6 or fewer carbon atoms, more preferably 4 or fewer, and even more preferably 3 or fewer.

[0589] The aforementioned fluorinated alkyl group is an alkyl group containing at least one fluorine atom, and the number of carbon atoms is one or more. Preferably, the number of carbon atoms in the aforementioned fluorinated alkyl group is 6 or less, more preferably 4 or less, and even more preferably 3 or less.

[0590] As for Y, -H, -F or -CF3 are preferred, and -F is more preferred.

[0591] In the above general formula (5), Z may be the same or different, and may be -H, -F, alkyl or fluoroalkyl.

[0592] The alkyl group described above is an alkyl group that does not contain fluorine atoms and has 1 or more carbon atoms. Preferably, the alkyl group has 6 or fewer carbon atoms, more preferably 4 or fewer, and even more preferably 3 or fewer.

[0593] The aforementioned fluorinated alkyl group is an alkyl group containing at least one fluorine atom, and the number of carbon atoms is one or more. Preferably, the number of carbon atoms in the aforementioned fluorinated alkyl group is 6 or less, more preferably 4 or less, and even more preferably 3 or less.

[0594] As Z is mentioned above, -H, -F or -CF3 are preferred, and -F is more preferred.

[0595] In the above general formula (5), at least one of X, Y and Z preferably contains a fluorine atom. For example, X can be -H, and Y and Z can be -F.

[0596] In the above general formula (5), Rf is a fluorinated alkylene group with 1 to 40 carbon atoms, or a fluorinated alkylene group with ether bonds having 2 to 100 carbon atoms. It should be noted that the above fluorinated alkylene group with ether bonds having 2 to 100 carbon atoms does not contain a structure with an oxygen atom at the end, but is an alkylene group with ether bonds between carbon atoms.

[0597] The number of carbon atoms in the aforementioned fluorinated alkylene group is preferably 2 or more. Furthermore, it is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less. Examples of the aforementioned fluorinated alkylene group include -CF2-, -CH2CF2-, -CF2CF2-, -CF2CH2-, -CF2CF2CH2-, -CF(CF3)-, -CF(CF3)CF2-, and -CF(CF3)CH2-. The aforementioned fluorinated alkylene group is preferably a perfluoroalkylene group.

[0598] The number of carbon atoms in the aforementioned fluorinated alkylene group having an ether bond is preferably 3 or more. Furthermore, it is preferably 60 or less, more preferably 30 or less, and even more preferably 12 or less.

[0599] For example, the following formula is also preferred:

[0600] [Chemistry 25]

[0601]

[0602] (where Z) 1 For F or CF3; Z 2 and Z 3 H or F respectively; Z 4 Let H, F, or CF3 be the integers p1+q1+r1, 0 to 10; s1 be 0 or 1; t1 be 0 to 5, where Z is an integer. 3 and Z 4 When all are H, p1+q1+r1+s1 is not 0, as shown by the divalent group.

[0603] Specifically, examples of fluorinated alkylene groups with ether bonds include -CF(CF3)CF2-O-CF(CF3)- and -(CF(CF3)CF2-O). n -CF(CF3)- (where n is an integer from 1 to 10), -CF(CF3)CF2-O-CF(CF3)CH2-, -(CF(CF3)CF2-O) n -CF(CF3)CH2- (where n is an integer from 1 to 10), -CH2CF2CF2O-CH2CF2CH2-, -CF2CF2CF2O-CF2CF2-, -CF2CF2CF2O-CF2CF2CH2-, -CF2CF2O-CF2CF2-, -CF2CF2O-CF2CH2-, -CF2CF2O-CF2-, -CF2CF2O-CF2CH2-, -CF(CF3)CH2-, etc.

[0604] The fluorinated alkylene groups with ether bonds mentioned above are preferably perfluoroalkylene groups.

[0605] In the above general formula (5), Y 3 It can be -COOM, -SO3M or -OSO3M (M is H, a metal atom, or NR). 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It can be an H group or an organic group, which can be the same or different. Any two can bond together to form a ring.

[0606] As R 7 H or C are preferred 1-10 Organic groups, more preferably H or C 1-4 The organic groups, preferably H or C, are preferred. 1-4 Alkyl groups.

[0607] Examples of metal atoms that can be used as the aforementioned metal atoms include alkali metals (Group 1) and alkaline earth metals (Group 2), with Na, K, or Li being preferred.

[0608] As for M above, -H, a metal atom, or -NR is preferred. 7 4. More preferably -H, alkali metal (Group 1), alkaline earth metal (Group 2) or -NR 7 4. Further preferred are -H, -Na, -K, -Li or -NH4, even more preferred are -Na, -K or -NH4, particularly preferred are -Na or -NH4, and most preferred are -NH4.

[0609] As mentioned above, Y 3 Preferably -COOM or -SO3M, more preferably -COOM.

[0610] As a monomer represented by general formula (5), for example, the following formula (5a) can be exemplified:

[0611] CX h 2=CFCF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-Y 3 (5a)

[0612] (In the formula, each X) h Same, indicating F or H. n5 represents 0 or an integer from 1 to 10, Y 3 Fluoroallyl ether compounds (as defined above) are preferred substances.

[0613] In general formula (5a), from the perspective of obtaining PTFE particles with small primary particle size, n5 is preferably an integer from 0 to 5, more preferably 0, 1, or 2, and even more preferably 0 or 1. From the perspective of obtaining suitable water solubility and surface activity, the above-mentioned Y 3 Preferably, -COOM is preferred, and from the perspective of minimizing its residue as an impurity and improving the heat resistance of the resulting composition and the stretched body obtained from the composition, the M is preferably H or NH4.

[0614] The monomer represented by general formula (5) is preferably the monomer (5b) represented by the following general formula (5b).

[0615] CH2=CF(-CF2-O-Rf-Y 3 (5b)

[0616] (where Rf and Y are in the formula) 3 Same as above.

[0617] As a monomer represented by general formula (5b), specifically, the following formula can be cited.

[0618] [Chemistry 26]

[0619]

[0620] (where Z) 1 For F or CF3; Z 2 and Z 3 H or F respectively; Z 4 For H, F, or CF3; p1+q1+r1 is an integer from 0 to 10; s1 is 0 or 1; t1 is an integer from 0 to 5, Y 3 Same as above. Wherein, Z 3 and Z 4 The monomers shown are those where p1+q1+r1+s1 are not 0 when all are H. More specifically, preferred examples include...

[0621] [Chemistry 27]

[0622]

[0623] CH2=CFCF2OCH2CF2-Y 3 , CH2=CFCF2O(CH2CF2CF2O)CH2CF2-Y 3 ,

[0624] CH2=CFCF2OCH2CF2CH2-Y 3 ,

[0625] CH2=CFCF2O(CH2CF2CF2O)CH2CF2CH2-Y 3 ,

[0626] CH2=CFCF2OCF2CF2-Y 3 , CH2=CFCF2O(CF2CF2CF2O)CF2CF2-Y 3 ,

[0627] CH2=CFCF2OCF2CF2CH2-Y 3 ,

[0628] CH2=CFCF2O(CF2CF2CF2O)CF2CF2CH2-Y 3 ,

[0629] CH2=CFCF2OCF2-Y 3 CH2=CFCF2O(CF2CF2O)CF2-Y 3 ,

[0630] CH2=CFCF2OCF2CH2-Y 3 ,

[0631] CH2=CFCF2O(CF2CF2O)CF2CH2-Y 3 ,

[0632] etc., among which the preferred option is

[0633] [Chemistry 28]

[0634]

[0635] As the monomer shown in the above general formula (5b), Y in the preferred formula (5b) 3For -COOM, it is particularly preferred to select at least one of the group consisting of CH2=CFCF2OCF(CF3)COOM and CH2=CFCF2OCF(CF3)CF2OCF(CF3)COOM (where M is the same as defined above), and more preferably CH2=CFCF2OCF(CF3)COOM.

[0636] The monomer represented by general formula (5) is preferably the monomer (5c) represented by the following general formula (5c).

[0637] CX 2 2=CFCF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-Y 3 (5c)

[0638] (In the formula, each X) 2 Same, indicating F or H. n5 represents 0 or an integer from 1 to 10, Y 3 Same as the definition above.

[0639] In the above formula (5c), from the perspective of the stability of the obtained aqueous dispersion, n5 is preferably an integer from 0 or 1 to 5, more preferably 0, 1 or 2, and even more preferably 0 or 1. From the perspective of obtaining suitable water solubility and stability of the aqueous dispersion, the above Y 3 Preferred -COOM 1 From the perspective of minimizing the residue as an impurity and improving the heat resistance of the resulting molded article, the above-mentioned M... 1 H or NH4 is preferred.

[0640] Examples of perfluorovinylalkyl compounds represented by formula (5c) above include CH2=CFCF2OCF(CF3)COOM. 1 , CH2=CFCF2OCF(CF3)CF2OCF(CF3)COOM 1 (where M is in the formula) 1 Same as the definition above).

[0641] In addition, as monomers represented by general formula (5), examples of monomers represented by general formula (5d) and general formula (5e) can also be given.

[0642] Examples include:

[0643] CF2 = CFCF2-O-Rf-Y 3 (5d)

[0644] CF2 = CF - Rf - Y 3 (5e)

[0645] (where Rf and Y are in the formula)3 Same as above)

[0646] More specifically, examples include:

[0647] [Chemistry 29]

[0648] CF2 = CFCF2OCF2CF2CF2-Y 3 ,

[0649]

[0650] CF2=CFCF2OCF2CF2CF2CH2-Y 3 ,

[0651] wait.

[0652] In the above general formula (6), X is -H or -F. X can be both -F or at least one -H. For example, one can be -F and the other -H, or both can be -H.

[0653] In the above general formula (6), Y is -H, -F, alkyl or fluorinated alkyl.

[0654] The alkyl group described above is an alkyl group that does not contain fluorine atoms and has 1 or more carbon atoms. Preferably, the alkyl group has 6 or fewer carbon atoms, more preferably 4 or fewer, and even more preferably 3 or fewer.

[0655] The aforementioned fluorinated alkyl group is an alkyl group containing at least one fluorine atom, and the number of carbon atoms is one or more. Preferably, the number of carbon atoms in the aforementioned fluorinated alkyl group is 6 or less, more preferably 4 or less, and even more preferably 3 or less.

[0656] As for Y, -H, -F or -CF3 are preferred, and -F is more preferred.

[0657] In the above general formula (6), at least one of X and Y preferably contains a fluorine atom. For example, X can be -H, and Y and Z can be -F.

[0658] In the above general formula (6), Rf is a fluorinated alkylene group with 1 to 40 carbon atoms, or a fluorinated alkylene group with ether bonds having 2 to 100 carbon atoms. It should be noted that the above fluorinated alkylene group with ether bonds having 2 to 100 carbon atoms does not contain a structure with an oxygen atom at the end, but is an alkylene group with ether bonds between carbon atoms.

[0659] The number of carbon atoms in the aforementioned fluorinated alkylene group is preferably 2 or more. Furthermore, it is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less. Examples of the aforementioned fluorinated alkylene group include -CF2-, -CH2CF2-, -CF2CF2-, -CF2CH2-, -CF2CF2CH2-, -CF(CF3)-, -CF(CF3)CF2-, and -CF(CF3)CH2-. The aforementioned fluorinated alkylene group is preferably a perfluoroalkylene group.

[0660] The monomer shown in the above general formula (6) is preferably selected from at least one of the groups consisting of the monomers shown in the following general formulas (6a), (6b), (6c) and (6d).

[0661] CF2 = CF - O - (CF2) n1 -Y 3 (6a)

[0662] (In the formula, n1 represents an integer from 1 to 10, Y) 3 Indicates -SO3M 1 or -COOM 1 M 1 Represents H, metal atoms, and NR 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 (This indicates an H group or an organic group.)

[0663] CF2=CF-O-(CF2C(CF3)F) n2 -Y 3 (6b)

[0664] (In the formula, n2 represents an integer from 1 to 5, Y) 3 Same as the definition above.

[0665] CF2 = CF-O-(CFX) 1 ) n3 -Y 3 (6c)

[0666] (where X) 1 Let F or CF3 represent n3, where n3 represents an integer from 1 to 10, and Y represents n3. 3 Same as the definition above.

[0667] CF2 = CF-O-(CF2CFX) 1 O) n4 -CF2CF2-Y 3 (6d)

[0668] (In the formula, n4 represents an integer from 1 to 10, Y) 3 and X 1Same as the definition above.

[0669] In the above formula (6a), n1 is preferably an integer of 5 or less, more preferably an integer of 2 or less. From the perspective of obtaining moderate water solubility and stability of the aqueous dispersion, the above Y 3 Preferred -COOM 1 From the perspective of minimizing the residue as an impurity and improving the heat resistance of the resulting molded article, M 1 H or NH4 is preferred.

[0670] Examples of perfluorovinylalkyl compounds represented by formula (6a) above include, for example, CF2=CF-O-CF2COOM. 1 (where M is in the formula) 1 Same as the definition above).

[0671] In the above formula (6b), from the perspective of the stability of the obtained aqueous dispersion, n2 is preferably an integer of 3 or less; from the perspective of obtaining moderate water solubility and stability of the aqueous dispersion, Y 3 Preferred -COOM 1 From the perspective of minimizing the residue as an impurity and improving the heat resistance of the resulting molded article, M 1 H or NH4 is preferred.

[0672] In the above formula (6c), from the perspective of water solubility, n3 is preferably an integer of 5 or less; from the perspective of obtaining moderate water solubility and stability of the aqueous dispersion, Y... 3 Preferred -COOM 1 From the perspective of improving dispersion stability, the above-mentioned M 1 H or NH4 is preferred.

[0673] In the above formula (6d), from the perspective of the stability of the aqueous dispersion, the above X... 1 Preferably -CF3, from the perspective of water solubility, the above-mentioned n4 is preferably an integer of 5 or less, and from the perspective of obtaining moderate water solubility and stability of the aqueous dispersion, the above-mentioned Y 3 Preferred -COOM 1 The above M 1 H or NH4 is preferred.

[0674] Examples of perfluorovinyl ether compounds represented by formula (6d) above include CF2=CFOCF2CF(CF3)OCF2CF2COOM. 1 (where M is in the formula) 1 (Indicates H, NH4, or alkali metal).

[0675] In the above general formula (7), Rf is preferably a fluorinated alkylene group having 1 to 40 carbon atoms. In general formula (7), at least one of X and Y preferably contains a fluorine atom.

[0676] The monomer represented by the above general formula (7) is preferably selected from the following general formula (7a):

[0677] CF2 = CF - (CF2) n1 -Y 3 (7a)

[0678] (In the formula, n1 represents an integer from 1 to 10, Y) 3 The monomers shown in the above definition, and the following general formula (7b):

[0679] CF2 = CF - (CF2C(CF3)F) n2 -Y 3 (7b)

[0680] (In the formula, n2 represents an integer from 1 to 5, Y) 3 At least one of the groups consisting of monomers as defined above.

[0681] The above Y 3 Preferred - SO3M 1 or -COOM 1 M 1 Preferably, H, metal atoms, and NR are preferred. 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents. The above R... 7 It represents H or an organic group.

[0682] In the above formula (7a), n1 is preferably an integer of 5 or less, more preferably an integer of 2 or less. From the perspective of obtaining moderate water solubility and stability of the aqueous dispersion, the above Y 3 Preferred -COOM 1 From the perspective of minimizing the residue as an impurity and improving the heat resistance of the resulting molded article, M 1 H or NH4 is preferred.

[0683] Examples of perfluorovinylalkyl compounds represented by formula (7a) above include, for example, CF2=CFCF2COOM. 1 (where M is in the formula) 1 Same as the definition above).

[0684] In the above formula (7b), from the perspective of the stability of the obtained aqueous dispersion, n2 is preferably an integer of 3 or less; from the perspective of obtaining moderate water solubility and stability of the aqueous dispersion, Y 3Preferred -COOM 1 From the perspective of minimizing the residue as an impurity and improving the heat resistance of the resulting molded article, M 1 H or NH4 is preferred.

[0685] The content of the modified monomer (A) is preferably in the range of 0.00001 to 1.0% by mass. As a lower limit, it is more preferably 0.0001% by mass, further preferably 0.001% by mass, even more preferably 0.005% by mass, and particularly preferably 0.009% by mass. As an upper limit, it is preferably 0.90% by mass, more preferably 0.50% by mass, further preferably 0.40% by mass, even more preferably 0.30% by mass, particularly preferably 0.10% by mass, and particularly preferably 0.05% by mass.

[0686] In the manufacture of the aforementioned TFE polymer, the polymer (1) can be used within the scope of use described in the manufacturing method of the present invention. The concentration of the polymer (1) is not particularly limited as long as it falls within the aforementioned range, and is typically added at or below the critical micelle concentration (CMC) at the start of polymerization. If a large amount is added, needle-like particles with a large aspect ratio are generated, the aqueous dispersion becomes gel-like, and its stability is compromised. The lower limit of the amount of the polymer (1) relative to the aqueous medium is preferably 0.0001% by mass, more preferably 0.001% by mass, further preferably 0.01% by mass, and particularly preferably 0.1% by mass. The upper limit of the amount of the polymer (1) relative to the aqueous medium is preferably 10% by mass, more preferably 5% by mass, further preferably 3% by mass, and particularly preferably 2% by mass.

[0687] The polymer (1) can be added to the reaction vessel once before the start of polymerization, once after the start of polymerization, added in several installments during polymerization, or added continuously during polymerization.

[0688] In the manufacture of the aforementioned TFE polymer, organic peroxides such as persulfates (e.g., ammonium persulfate), disuccinic acid peroxide, and diglutaric acid peroxide can be used as polymerization initiators, either alone or in mixtures thereof. Alternatively, they can be used in conjunction with a reducing agent to create a redox system. Furthermore, free radical scavengers such as hydroquinone and catechol, or peroxide decomposers such as ammonium sulfite, can be added during polymerization to adjust the free radical concentration within the system.

[0689] As polymerization initiators for the aforementioned redox system, redox initiators combining oxidants and reductants are preferred. Examples of oxidants include persulfates, organic peroxides, potassium permanganate, manganese triacetate, and cerium ammonium nitrate. Examples of reductants include sulfites, bisulfites, bromates, diimides, and oxalic acid. Examples of persulfates include ammonium persulfate and potassium persulfate. Examples of sulfites include sodium sulfite and ammonium sulfite. To improve the decomposition rate of the initiator, it is also preferable to add copper or iron salts to the combination of redox initiators. Examples of copper salts include copper(II) sulfate, and examples of iron salts include ferric(II) sulfate.

[0690] Examples of redox initiators include potassium permanganate / oxalic acid, ammonium persulfate / bisulfite / ferric sulfate, manganese triacetate / oxalic acid, cerium ammonium nitrate / oxalic acid, and bromate / bisulfite, with potassium permanganate / oxalic acid being preferred. When using a redox initiator, either the oxidant or the reducing agent can be added to the polymerization reactor beforehand, followed by the addition of the other continuously or intermittently to initiate polymerization. For example, when using potassium permanganate / oxalic acid, it is preferable to add oxalic acid to the polymerization reactor and then continuously add potassium permanganate thereto.

[0691] In the manufacture of the aforementioned TFE polymer, known substances can be used as chain transfer agents, such as saturated hydrocarbons like methane, ethane, propane, and butane; halogenated hydrocarbons like chloromethane, dichloromethane, and difluoroethane; alcohols like methanol and ethanol; and hydrogen, etc., preferably substances that are in a gaseous state at room temperature and pressure.

[0692] The amount of the chain transfer agent used is typically 1 to 10,000 ppm, preferably 1 to 5,000 ppm, relative to the total amount of TFE supplied. The amount can be 1 to 1,000 ppm or 1 to 500 ppm.

[0693] In the manufacture of the aforementioned TFE polymer, a saturated hydrocarbon with 12 or more carbon atoms, which is substantially inert in the reaction and is liquid under the aforementioned reaction conditions, can be used as a dispersion stabilizer for the reaction system at 2 to 10 parts by mass relative to 100 parts by mass of the aqueous medium. Additionally, ammonium carbonate, ammonium phosphate, etc., can be added as a buffer to adjust the pH of the reaction.

[0694] At the point of termination of polymerization of the above-mentioned TFE polymer, an aqueous dispersion with a solid content concentration of 1.0 to 70% by mass and an average primary particle size of 50 to 500 nm can be obtained. The above-mentioned aqueous dispersion contains the above-mentioned polymer (1) and a fluoropolymer. In addition, by using the above-mentioned polymer (1), an aqueous dispersion of particles formed by the TFE polymer with a small particle size of less than 0.5 μm can be obtained.

[0695] The lower limit of the above-mentioned solid component concentration is preferably 5% by mass, more preferably 8% by mass. The upper limit is not particularly limited and can be 40% by mass or 35% by mass.

[0696] The lower limit of the above-mentioned average primary particle size is preferably 100 nm, more preferably 150 nm. The upper limit is preferably 400 nm, more preferably 350 nm.

[0697] Fine powder can be produced by precipitating the above-mentioned aqueous dispersion. The above-mentioned aqueous dispersion of TFE polymer can be precipitated, washed, and dried to produce fine powder for various applications. When precipitating the above-mentioned aqueous dispersion of TFE polymer, the aqueous dispersion obtained by polymerization of polymer emulsions, etc., is usually diluted with water to a polymer concentration of 10-20% by mass. Depending on the situation, after adjusting the pH to neutral or alkaline, the mixture is stirred more vigorously than the stirring during the reaction in a container equipped with a stirrer. During the above precipitation, water-soluble organic compounds such as methanol and acetone, inorganic salts such as potassium nitrate and ammonium carbonate, and inorganic acids such as hydrochloric acid, sulfuric acid, and nitric acid can be added as precipitating agents while stirring simultaneously. The above precipitation can also be carried out continuously using a pipe mixer or the like.

[0698] From a productivity standpoint, it is preferable that the concentration of uncoagulated TFE polymer in the wastewater generated by the above coagulation is low, more preferably less than 0.4% by mass, and particularly preferably less than 0.3% by mass.

[0699] Before or during the precipitation process, by adding pigments for coloring or various fillers for improving mechanical properties, a fine powder of TFE polymer containing pigments or fillers can be obtained that is uniformly mixed with pigments or fillers.

[0700] The drying of the wet powder obtained by precipitating the aqueous dispersion of the above-mentioned TFE polymer is usually carried out using methods such as vacuum, high frequency, or hot air while keeping the wet powder in a nearly non-flowing state, preferably in a static state. Friction between powders, especially at high temperatures, usually has an adverse effect on fine TFE polymer powders. This is because the particles composed of this TFE polymer have the property of easily fibrillating even under small shear forces, thus losing their originally stable particle structure.

[0701] The drying process described above is carried out at a drying temperature of 10–250°C, preferably 100–200°C. The drying temperature can also be below 200°C.

[0702] The obtained TFE polymer fine powder is preferably used for molding. Suitable applications include pipes for hydraulic systems and fuel systems in aircraft and automobiles, flexible hoses for reagents and vapors, and wire coating applications.

[0703] The aqueous dispersion of the TFE polymer obtained by the above polymerization is preferably stabilized by adding a nonionic surfactant, further concentrated, and then an organic or inorganic filler is added according to the purpose to prepare a composition for various applications. The above composition, when coated onto a substrate formed of metal or ceramic, can produce a coating surface with excellent non-adhesiveness, low coefficient of friction, gloss, smoothness, abrasion resistance, weather resistance, and heat resistance, suitable for coating rollers or cooking devices, impregnation processing of glass cloth, etc.

[0704] Organosols of TFE polymers can also be prepared from the above-mentioned aqueous dispersion. The organosols may comprise the above-mentioned TFE polymer and an organic solvent. Examples of organic solvents include ether-based solvents, ketone-based solvents, alcohol-based solvents, amide-based solvents, ester-based solvents, aliphatic hydrocarbon-based solvents, aromatic hydrocarbon-based solvents, and halogenated hydrocarbon-based solvents. N-methyl-2-pyrrolidone, dimethylacetamide, etc., may be appropriately used. The preparation of the above-mentioned organosols can be carried out, for example, by the method described in International Publication No. 2012 / 002038.

[0705] The aqueous dispersion of the aforementioned TFE polymer or the fine powder of the aforementioned TFE polymer is also preferably used as a processing aid. When used as a processing aid, by mixing the aforementioned aqueous dispersion or the aforementioned fine powder into the main polymer, the melt strength of the main polymer during melt processing can be improved, and the mechanical strength, electrical properties, flame retardancy, anti-dripping properties during combustion, and sliding properties of the obtained polymer can be improved.

[0706] The aqueous dispersion of the above-mentioned TFE polymer or the fine powder of the above-mentioned TFE polymer is also preferably used as a battery binder and for dustproof applications.

[0707] The aqueous dispersion or fine powder of the aforementioned TFE polymer is preferably used as a processing aid after being compounded with resins other than TFE polymers. The aqueous dispersion or fine powder is suitable as a raw material for PTFE as described in, for example, Japanese Patent Application Publication No. 11-49912, US Patent No. 5804654, Japanese Patent Application Publication No. 11-29679, and Japanese Patent Application Publication No. 2003-2980. Processing aids using the aforementioned aqueous dispersion or fine powder are in no way inferior to those described in the aforementioned publications.

[0708] The aqueous dispersion of the above-mentioned TFE polymer is preferably prepared into a coprecipitate powder by mixing it with an aqueous dispersion of a melt-processable fluoropolymer and allowing it to precipitate. The coprecipitate powder is suitable as a processing aid.

[0709] Examples of melt-processable fluoropolymers include FEP, PFA, ETFE, and ethylene / TFE / HFP copolymer [EFEP], with FEP being the preferred choice.

[0710] The aqueous dispersion described above preferably includes the melt-processable fluoropolymer. Examples of melt-processable fluoropolymers include FEP, PFA, ETFE, and EFEP. The aqueous dispersion containing the melt-processable fluoropolymer can be used as a coating. The melt-processable fluoropolymer enables the TFE polymer particles to fuse fully together, thereby improving film-forming properties and giving the resulting coating a glossy appearance.

[0711] The non-fluorinated resin to which the co-precipitated powder is added can be in powder, granular, or emulsion form. From the perspective of thoroughly mixing the resins, it is preferable to add the resin while applying shear force using known methods such as extrusion mixing or roll mixing.

[0712] The aqueous dispersion of the above-mentioned TFE polymer is also preferably used as a dust suppressant. This dust suppressant can be used in the following methods: mixing with a dust-generating substance and applying compression-shear action to the mixture at a temperature of 20–200°C, thereby fibrillating the TFE polymer and suppressing dust from the dust-generating substance; for example, the methods described in Japanese Patent No. 2827152 and Japanese Patent No. 2538783.

[0713] The aqueous dispersion of the above-mentioned TFE polymer can be suitably used in, for example, the dust suppressant composition described in International Publication No. 2007 / 004250, and can also be suitably used in the dust suppressant treatment method described in International Publication No. 2007 / 000812.

[0714] The dust suppressant described above is suitable for dust suppression in the fields of building materials, soil stabilization materials, solidification materials, fertilizers, filling treatment of incinerator ash and hazardous substances, explosion protection, cosmetics, and pet litter such as cat litter.

[0715] The aqueous dispersion of the aforementioned TFE polymer is also preferably used as a raw material for obtaining TFE polymer fibers via dispersion spinning. The dispersion spinning method involves mixing the aqueous dispersion of the aforementioned TFE polymer with an aqueous dispersion of a matrix polymer, extruding the mixture to form an intermediate fiber structure, and then sintering the intermediate fiber structure to decompose the matrix polymer and sinter the TFE polymer particles, thereby obtaining TFE polymer fibers.

[0716] High molecular weight PTFE can also be manufactured using the above-described polymer (1). That is, in the manufacturing method of the present invention using the above-described polymer (1), even without using existing fluorinated surfactants, it is surprisingly possible to manufacture PTFE with the same molecular weight as that manufactured using existing fluorinated surfactants.

[0717] High molecular weight PTFE powder obtained through polymerization possesses stretchability and non-melt processability, making it useful as a raw material for stretched bodies (porous bodies). When this stretched body is a membrane (PTFE stretched membrane or PTFE porous membrane), it can be stretched using known PTFE stretching methods. Through stretching, high molecular weight PTFE readily fibrils, forming a PTFE porous body (membrane) composed of nodules and fibers.

[0718] Preferably, the sheet or rod-shaped paste extruder is rolled along the extrusion direction to obtain a uniaxially stretched film.

[0719] Furthermore, biaxially oriented films can also be obtained by stretching along the width direction using a tenter frame or similar equipment.

[0720] It is also preferable to perform a semi-firing process before stretching.

[0721] This invention also relates to a method for manufacturing a stretched body, characterized by a step of stretching the polytetrafluoroethylene obtained by the above-described manufacturing method. The stretching can be performed using existing, known PTFE stretching methods and conditions, and is not limited thereto.

[0722] The present invention also provides a method for manufacturing a stretched body, characterized by comprising the following steps: polymerizing tetrafluoroethylene in an aqueous medium in the presence of a polymer (1) containing a polymerization unit (1) to obtain polytetrafluoroethylene, wherein the polymer (1) is based on a monomer represented by the following general formula (1); and stretching the obtained polytetrafluoroethylene.

[0723] CX2=CY(-CZ2-O-Rf-A) (1)

[0724] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0725] This PTFE stretchable body is a porous body with high porosity, and can be appropriately used as filter media for various precision filters such as air filters and reagent filters, as well as support material for polymer electrolyte membranes.

[0726] In addition, it is also useful as a material for products used in the fields of fibers, medicine, electrochemistry, sealing materials, air filtration, ventilation / internal pressure regulation, liquid filtration, and general consumables.

[0727] The following examples illustrate specific uses.

[0728] Electrochemistry

[0729] Dielectric prepregs, EMI shielding materials, heat transfer materials, etc. More specifically, printed circuit boards, electromagnetic shielding materials, insulating and heat transfer materials, insulating materials, etc.

[0730] Sealing materials field

[0731] Gaskets, sealing gaskets, pump diaphragms, pump tubing, sealing materials for aircraft, etc.

[0732] air filtration field

[0733] ULPA filters (for semiconductor manufacturing), HEPA filters (for hospitals and semiconductor manufacturing), cylindrical cartridge filters (for industrial use), bag filters (for industrial use), heat-resistant bag filters (for exhaust gas treatment), heat-resistant pleated filters (for exhaust gas treatment), SINBRAN filters (for industrial use), catalytic filters (for exhaust gas treatment), filters with adsorbents (for HDD assembly), air filters with adsorbents (for HDD assembly), air filters (for HDD assembly, etc.), vacuum cleaner filters (for vacuum cleaners), general-purpose multi-layer felt, GT cartridge filters (for interchangeable parts suitable for GT), cooling filters (for electronic device housings), etc.

[0734] Ventilation / Internal Pressure Adjustment

[0735] Freeze-drying materials such as freeze-drying containers; automotive ventilation materials suitable for electronic circuits or lights; container applications such as container lids; protective ventilation applications suitable for electronic devices containing small terminals such as input board terminals or mobile phone terminals; medical ventilation applications, etc.

[0736] Liquid filtration field

[0737] Semiconductor liquid filters (for semiconductor manufacturing), hydrophilic PTFE filters (for semiconductor manufacturing), filters suitable for chemicals (for reagent processing), filters for pure water production lines (for pure water production), backwashing type liquid filters (for industrial wastewater treatment), etc.

[0738] General consumables sector

[0739] Clothing, cable conduits (removable cables suitable for motorcycles), motorcycle clothing, cast padding (medical protective gear), vacuum cleaner filters, bagpipes (musical instruments), cables (signal cables for guitars, etc.), strings (for stringed instruments), etc.

[0740] Fiber field

[0741] PTFE fiber (fiber material), sewing thread (fabric), knitting thread (fabric), rope, etc.

[0742] medical field

[0743] Intraocular implants (stretching materials), artificial blood vessels, catheters, general surgery (tissue enhancement materials), head and neck products (dura mater substitutes), intraoral health (tissue regeneration medicine), and plastic surgery (bandages), etc.

[0744] Low molecular weight PTFE can also be manufactured using the above polymer (1).

[0745] Low molecular weight PTFE can be manufactured through polymerization, or high molecular weight PTFE obtained through polymerization can be reduced in molecular weight using known methods (thermal decomposition, radiation decomposition, etc.).

[0746] Low molecular weight PTFE (also known as PTFE micro powder) with a molecular weight of less than 600,000 has excellent chemical stability, extremely low surface energy, and is not prone to fibrillation. Therefore, it is suitable as an additive for improving lubricity and coating surface texture, and is used in the manufacture of plastics, inks, cosmetics, coatings, greases, office automation equipment parts, colorants, etc. (see, for example, Japanese Patent Application Publication No. 10-147617).

[0747] Alternatively, in the presence of a chain transfer agent, the polymerization initiator and the polymer (1) can be dispersed in an aqueous medium to polymerize TFE or a monomer that can copolymerize with TFE, thereby obtaining low molecular weight PTFE.

[0748] When using the low molecular weight PTFE obtained by the above polymerization as a powder, it can be produced as powder particles by precipitating the above aqueous dispersion.

[0749] In this invention, high molecular weight PTFE refers to PTFE that has non-melt processability and fibrillation properties. Conversely, low molecular weight PTFE refers to PTFE that has melt processability but does not have fibrillation properties.

[0750] The aforementioned non-melting processability refers to the property that the melt flow rate cannot be determined at temperatures above the crystallization melting point, according to ASTM D-1238 and D-2116.

[0751] The presence or absence of fibrillability can be determined using "paste extrusion," a representative method for molding powders made from TFE polymers, i.e., "high molecular weight PTFE powder." This is because, typically, high molecular weight PTFE exhibits fibrillability when paste extrusion is possible. If the unfired molded article obtained by paste extrusion does not possess substantial strength or elongation—for example, if the elongation is 0% and it breaks upon stretching—it can be considered to lack fibrillability.

[0752] The preferred standard specific gravity (SSG) of the aforementioned high molecular weight PTFE is 2.130 to 2.280. This standard specific gravity is determined using samples molded according to ASTM D4895-89 and measured by the water displacement method according to ASTM D-792. In this invention, "high molecular weight" refers to a standard specific gravity falling within the aforementioned range.

[0753] The complex viscosity of the aforementioned low molecular weight PTFE at 380℃ is 1×10⁻⁶. 2 ~7×10 5 Pa·s. In this invention, "low molecular weight" means that the complex viscosity is within the range described above.

[0754] The complex viscosity of the high molecular weight PTFE is significantly higher than that of the low molecular weight PTFE, making it difficult to accurately measure its complex viscosity. On the other hand, while the complex viscosity of the low molecular weight PTFE can be measured, it is difficult to obtain molded articles suitable for measuring standard specific gravity from the low molecular weight PTFE, making it difficult to accurately measure its standard specific gravity. Therefore, in this invention, standard specific gravity is used as an indicator of the molecular weight of the high molecular weight PTFE, and complex viscosity is used as an indicator of the molecular weight of the low molecular weight PTFE. It should be noted that methods for directly measuring specific molecular weights for both the high molecular weight and low molecular weight PTFE are unknown.

[0755] The peak temperature of the aforementioned high molecular weight PTFE is preferably 333–347°C, more preferably 335–345°C. The peak temperature of the aforementioned low molecular weight PTFE is preferably 322–333°C, more preferably 324–332°C. The aforementioned peak temperature corresponds to the maximum value in the following pyrolysis curve, which is the pyrolysis curve of PTFE that has not undergone a heating history to a temperature above 300°C when heated using a differential scanning calorimeter [DSC] at a rate of 10°C / min.

[0756] In the pyrolysis curve of PTFE that has not been heated to a temperature above 300°C using a differential scanning calorimeter (DSC) at a heating rate of 10°C / min, the high molecular weight PTFE preferably exhibits at least one endothermic peak in the range of 333 to 347°C, and the pyrolysis heat at 290 to 350°C calculated from the above pyrolysis curve is 62 mJ / mg or more.

[0757] Unburned tape (raw tape) can also be obtained from the PTFE fine powder obtained using the above polymer (1).

[0758] The polymer (1), byproducts of the polymer (1), and residual monomers are recovered and purified from the wastewater generated by the precipitation or washing process and / or the waste gas generated by the drying process, thereby enabling the reuse of the polymer (1), byproducts of the polymer (1), and residual monomers. There are no particular limitations on the method for performing the recovery and purification; known methods can be used. For example, the method described in Japanese Patent Publication No. 2011-520020 can be employed.

[0759] (II) Melt-processable fluoropolymers

[0760] (1) In the manufacturing method of the present invention, the polymerization of FEP is preferably carried out at a polymerization temperature of 10 to 150°C and a polymerization pressure of 0.3 to 6.0 MPaG.

[0761] The preferred monomer composition (mass%) of the FEP is TFE:HFP = (60–98):(2–40), more preferably (60–95):(5–40), and even more preferably (85–92):(8–15). As the above FEP, a perfluoro(alkyl vinyl ether) can also be used as a third component, modified in the range of 0.1–2% by mass of all monomers.

[0762] In the polymerization of the above-mentioned FEP, the above-mentioned polymer (1) can be used within the scope of use in the manufacturing method of the present invention, typically added in an amount of 0.0001 to 10% by mass relative to 100% by mass of the aqueous medium.

[0763] In the polymerization of FEP described above, cyclohexane, methanol, ethanol, propanol, ethane, propane, butane, pentane, hexane, carbon tetrachloride, chloroform, dichloromethane, chloromethane, etc. are preferably used as chain transfer agents, and ammonium carbonate, disodium hydrogen phosphate, etc. are preferably used as pH buffers.

[0764] The aqueous dispersion of FEP obtained by the manufacturing method of the present invention is concentrated and then dried to form a powder, followed by melt extrusion to form granules. The aqueous medium in the aqueous dispersion of FEP may contain additives such as nonionic surfactants, or may contain water-soluble organic solvents such as water-soluble alcohols, or may not contain water-soluble organic solvents.

[0765] In addition, as long as the extrusion conditions are generally capable of granulation, the extrusion conditions can be appropriately set for melt extrusion.

[0766] In the manufacturing method of the present invention, the obtained FEP may have terminal groups such as -CF3 and -CF2H at at least one of the polymer main chain and polymer side chain. Preferably, the content of thermally unstable groups such as -COOH, -CH2OH, -COF, -CF=CF-, -CONH2, and -COOCH3 (hereinafter referred to as "unstable terminal groups") is low or absent.

[0767] The aforementioned unstable terminal groups are chemically unstable, which not only reduces the heat resistance of the resin, but also contributes to the increased attenuation of the resulting wires.

[0768] In the manufacturing method of the present invention, it is preferable to use polymers at the point where polymerization is terminated at every 1×10 6 The method of manufacturing is to ensure that the total number of unstable terminal groups and -CF2H terminal groups in each carbon atom is less than 50. In each 1×10 6 The total number of the above-mentioned groups in each carbon atom is more preferably less than 20, and even more preferably less than 5. The above-mentioned unstable terminal groups and -CF2H terminal groups may also be absent, and all are -CF3 terminal groups.

[0769] Unstable terminal groups and -CF2H terminal groups can be stabilized by fluorination treatment, which converts them into -CF3 terminal groups. The fluorination treatment method is not particularly limited; examples include exposing the polymer to a fluorine radical source that generates fluorine radicals under fluorination conditions. Examples of such fluorine radical sources include fluorine gas, CoF3, AgF2, UF6, OF2, N2F2, CF3OF, and fluorinated halides (e.g., IF5, ClF3). Preferably, the method involves directly contacting the fluorinated gas with the FEP obtained by this invention. From a reaction control perspective, this contact is preferably performed using diluted fluorine gas with a fluorine concentration of 10–50% by mass. This diluted fluorine gas can be obtained by diluting the fluorine gas with an inert gas such as nitrogen or argon. The fluorine treatment is performed, for example, at a temperature of 100–250°C. It should be noted that the treatment temperature is not limited to the above range and can be appropriately set depending on the circumstances. The fluorine treatment is preferably performed by continuously or intermittently supplying diluted fluorine gas into the reactor. This fluorination treatment can be applied to dried powders after polymerization or to granules after melt extrusion.

[0770] The FEP obtained by the manufacturing method of the present invention has good formability, is not prone to molding defects, and has good heat resistance, chemical resistance, solvent resistance, insulation, and electrical properties.

[0771] The above-mentioned method for manufacturing FEP powder is a method of obtaining powder by drying and pulverizing the FEP obtained by the manufacturing method of the present invention.

[0772] The powder described above can be fluorinated. The method for manufacturing the fluorinated powder described above is a method of obtaining fluorinated powder by supplying fluorine gas to the powder obtained by the above powder manufacturing method to fluorinate it.

[0773] The above-mentioned method for manufacturing FEP granules is a method of obtaining granules by granulating the FEP obtained by the manufacturing method of the present invention.

[0774] The aforementioned granules can be fluorinated. The method for manufacturing the aforementioned fluorinated granules is a method of obtaining fluorinated granules by supplying fluorine gas to the granules obtained by the aforementioned granule manufacturing method to fluorinate them.

[0775] Therefore, this FEP can be supplied to the manufacture of various molded products such as coating materials, tubes, films, sheets, and filaments for wires, foamed wires, cables, conductors, etc.

[0776] (2) In the manufacturing method of the present invention, the polymerization of TFE / perfluoro (alkyl vinyl ether) copolymers such as PFA and MFA is generally preferably carried out at a polymerization temperature of 10 to 100°C and a polymerization pressure of 0.3 to 6.0 MPaG.

[0777] The preferred monomer composition (mol%) of the TFE / perfluoro(alkyl vinyl ether) copolymer is TFE:perfluoro(alkyl vinyl ether) = (90-99.7):(0.3-10), more preferably (97-99):(1-3). As the aforementioned perfluoro(alkyl vinyl ether), the formula CF2 = CFORf is preferred. 4 (where Rf) 4 It is a substance represented by a perfluoroalkyl group having 1 to 6 carbon atoms.

[0778] In the polymerization of the above-mentioned TFE / perfluoro (alkyl vinyl ether) copolymer, the above-mentioned polymer (1) can be used within the scope of use in the manufacturing method of the present invention, and is usually added in an amount of 0.0001 to 10% by mass relative to 100% by mass of the aqueous medium.

[0779] In the polymerization of the above-mentioned TFE / perfluoro (alkyl vinyl ether) copolymer, cyclohexane, methanol, ethanol, propanol, propane, butane, pentane, hexane, carbon tetrachloride, chloroform, dichloromethane, chloromethane, methane, ethane, etc. are preferably used as chain transfer agents, and ammonium carbonate, disodium hydrogen phosphate, etc. are preferably used as pH buffers.

[0780] The aqueous dispersion of TFE / perfluoro(alkyl vinyl ether) copolymers such as PFA and MFA obtained by the manufacturing method of the present invention is concentrated and post-treated as needed, then dried and made into powder, and then melt-extruded to form granules. The aqueous medium in the above-mentioned aqueous dispersion may contain additives such as nonionic surfactants, or may contain water-soluble organic solvents such as water-soluble alcohols, or may not contain water-soluble organic solvents.

[0781] In addition, as long as the extrusion conditions are generally capable of granulation, the extrusion conditions can be appropriately set for melt extrusion.

[0782] In the above copolymers, fluorine treatment is preferred for the purpose of improving their heat resistance and further enhancing the reagent permeation suppression effect of the molded articles.

[0783] Fluorine treatment is carried out by contacting the fluorine gas with a reagent through an inhibitor. However, since the reaction with fluorine is highly exothermic, it is suitable to dilute the fluorine with an inert gas such as nitrogen. The amount of fluorine in the fluorine / inert gas mixture is 1 to 100% by weight, preferably 10 to 25% by weight. The treatment temperature is 150 to 250°C, preferably 200 to 250°C, and the fluorine treatment time is 3 to 16 hours, preferably 4 to 12 hours. The gas pressure for fluorine treatment is in the range of 1 to 10 atm, preferably atmospheric pressure. When using a reactor at atmospheric pressure, the fluorine / inert gas mixture can be continuously passed into the reactor. As a result, the unstable ends of the above copolymer are converted into -CF3 ends, which are thermally stable.

[0784] As for the molding methods of the above copolymers and their compositions, they can be applied in the same way as existing PFA molding methods such as compression molding, transfer molding, extrusion molding, injection molding, and blow molding.

[0785] The desired molded products can be obtained through this molding method. Examples of molded products include sheets, films, gaskets, round bars, square bars, tube blanks, tubes, round channels, square channels, cans, wafer carriers, wafer boxes, beakers, filter housings, flow meters, pumps, valves, stopcocks, connectors, nuts, wires, heat-resistant wires, etc.

[0786] Among these, tubes, tube blanks, cans, connectors, etc., are particularly suitable for use in various chemical reaction devices, semiconductor manufacturing devices, and acid or alkali reagent supply devices that require impermeability of reagents.

[0787] Furthermore, a nonionic surfactant can be appropriately added to an aqueous dispersion of TFE / perfluoro(alkyl vinyl ether) copolymers such as PFA and MFA, and polyethersulfone, polyamide-imide, and / or polyimide, along with metal powder, can be dissolved or dispersed in an organic solvent as needed to obtain a base coat composition. This composition can also be used in coating methods for coating metal surfaces with fluoropolymers, comprising: applying the base coat composition to the metal surface; applying a melt-processable fluoropolymer composition to the resulting base coat; and firing the melt-processable fluoropolymer composition layer together with the base coat.

[0788] (3) In the manufacturing method of the present invention, the polymerization of ETFE is preferably carried out at a polymerization temperature of 10 to 100°C and a polymerization pressure of 0.3 to 2.0 MPaG.

[0789] The preferred monomer composition (mol%) of ETFE is TFE:ethylene = (50-99):(50-1). A third monomer can also be used as the ETFE, modified in the range of 0-20% by mass of all monomers. The preferred TFE:ethylene:third monomer ratio is (63-94):(27-2):(1-10). The preferred third monomers are perfluorobutylethylene, perfluorobutylethylene, 3,3,4,4,5,5,6,6,7,7,8,8,8-tetrafluoro-1-octene, 2,3,3,4,4,5,5-heptafluoro-1-pentene (CH2=CFCF2CF2CF2H), and 2-trifluoromethyl-3,3,3-trifluoropropylene ((CF3)2C=CH2).

[0790] In the polymerization of the above-mentioned ETFE, the above-mentioned polymer (1) can be used within the scope of use in the manufacturing method of the present invention, and is usually added in an amount of 0.0001 to 10% by mass relative to 100% by mass of the aqueous medium.

[0791] In the polymerization of ETFE described above, cyclohexane, methanol, ethanol, propanol, ethane, propane, butane, pentane, hexane, carbon tetrachloride, chloroform, dichloromethane, chloromethane, etc., are preferably used as chain transfer agents.

[0792] The aqueous dispersion of ETFE obtained by the manufacturing method of the present invention is concentrated and then dried to form a powder, followed by melt extrusion to form granules. The aqueous medium in the above-mentioned aqueous dispersion may contain additives such as nonionic surfactants, or may contain water-soluble organic solvents such as water-soluble alcohols, or may not contain water-soluble organic solvents.

[0793] In addition, as long as the extrusion conditions are generally capable of granulation, the extrusion conditions can be appropriately set for melt extrusion.

[0794] The ETFE flakes described above can be extruded into sheets. That is, ETFE powder or granules can be melted, continuously extruded through a die, and cooled to obtain a sheet-like molded product. Additives can be added to ETFE.

[0795] As additives, well-known substances can be appropriately used. Specific examples include ultraviolet absorbers, light stabilizers, antioxidants, infrared absorbers, flame retardants, flame-retardant fillers, organic pigments, inorganic pigments, and dyes. From the perspective of excellent weather resistance, inorganic additives are preferred.

[0796] The content of additives in the ETFE tablets is preferably 20% by mass or less, and particularly preferably 10% by mass or less, relative to the total mass of the ETFE tablets.

[0797] The aforementioned ETFE sheets have excellent mechanical strength and appearance, making them suitable as membrane materials (roofing materials, ceiling materials, exterior wall materials, interior wall materials, covering materials, etc.) for membrane structure buildings (sports facilities, garden facilities, atriums, etc.).

[0798] In addition, it can be used not only as a membrane material for membrane structure buildings, but also in the following materials: outdoor panels (soundproof walls, windbreaks, breakwaters, garage roofs, shopping malls, pedestrian street sidewalls, roofing materials), glass scattering prevention membranes, heat-resistant and water-resistant sheets, building materials (tent materials for tent warehouses, sunshade membrane materials, partial roofing materials for lighting, window materials to replace glass, fireproof partition membrane materials, curtains, external wall reinforcement, waterproof membranes, smoke-proof membranes, flame-retardant transparent partitions, road reinforcement, interior decoration (lighting, walls, blinds, etc.), exterior decoration (curtains, signs, etc.), etc.), leisure and lifestyle products (fishing rods, rackets, golf clubs, screens, etc.), automotive materials (canopies, damping materials, car bodies, etc.), aircraft materials, shipbuilding materials, appliance exteriors, storage tanks, container inner walls, filters, construction membrane materials, electronic materials (printed circuit boards, wiring boards, insulating films, release films, etc.), surface materials for solar cell modules, reflector protection materials for solar power generation, surface materials for solar water heaters, etc.

[0799] (4) The manufacturing method of the present invention can also be used to manufacture the electrolyte polymer precursor. In the manufacturing method of the present invention, the polymerization of the electrolyte polymer precursor is preferably carried out at a polymerization temperature of 10 to 100°C and a polymerization pressure of 0.1 to 2.0 MPaG. The electrolyte polymer precursor contains vinyl ether monomers as shown below, which can be converted into ion-exchangeable polymers by hydrolysis.

[0800] Vinyl ether monomers used as precursors for electrolyte polymers can be exemplified by:

[0801] General formula (150): CF2=CF-O-(CF2CFY) 151 -O)n-(CFY 152 ) m -A 151

[0802] (where Y) 151 This indicates a fluorine atom, a chlorine atom, a -SO2F group, or a perfluoroalkyl group. Perfluoroalkyl groups may contain ether-like oxygen atoms and -SO2F groups. n represents an integer from 0 to 3. n Y atoms 151 They can be the same or different. Y 152 This represents a fluorine atom, a chlorine atom, or a -SO2F group. m represents an integer from 1 to 5. The Y of m... 152 They can be the same or different. A 151 Indicates -SO2X 151 -COZ 151or -POZ 152 Z 153 X 151 Represents F, Cl, Br, I, -OR 151 or -NR 152 R 153 Z 151 Z 152 and Z 153 Same or different, indicating -NR 154 R 155 or -OR 156 R 151 R 152 R 153 R 154 R 155 and R 156 The same or different refers to fluorinated monomers represented by H, ammonium, alkali metal, alkyl, aryl, or sulfonyl groups that may contain fluorine atoms. The preferred monomer composition (mol%) of the electrolyte polymer precursor is TFE: vinyl ether = (50-99):(50-1), more preferably TFE: vinyl ether = (50-93):(50-7).

[0803] The aforementioned electrolyte polymer precursor can be modified using a third monomer within the range of 0–20% by mass of all monomers. Examples of the third monomer include multifunctional monomers such as CTFE, vinylidene fluoride, perfluoroalkyl vinyl ethers, and divinylbenzene.

[0804] The resulting electrolyte polymer precursor can be hydrolyzed using an alkaline solution and treated with an inorganic acid after being formed into a membrane, and then used as a polymer electrolyte membrane in fuel cells, electrolysis devices, and redox flow batteries.

[0805] Alternatively, hydrolysis can be carried out using an alkaline solution while maintaining the dispersed state of the electrolyte polymer precursor, thereby obtaining an electrolyte polymer dispersion.

[0806] Next, by heating it to above 120°C in a pressurized container, it can be dissolved in a water / alcohol mixture to form a solution.

[0807] The resulting solution can be used as a binder for electrodes, for example, or it can be compounded with various additives and cast into films for use in antifouling coatings, organic actuators, etc.

[0808] (5) TFE / VDF copolymer

[0809] In the manufacturing method of this invention, the polymerization temperature of the TFE / VDF copolymer is not particularly limited and can be 0 to 100°C. The polymerization pressure is appropriately set according to the polymerization temperature and other polymerization conditions, and is typically 0 to 9.8 MPaG.

[0810] The preferred monomer composition (mol%) of the TFE / VDF copolymer is TFE:VDF = (5-90):(95-10). A third monomer can also be used as the TFE / VDF copolymer, and modification can be performed within the range of 0-50 mol% of all monomers. Preferably, TFE:ethylene:third monomer = (30-85):(10-69.9):(0.1-10).

[0811] As the third monomer mentioned above, preferred

[0812] Formula: CX 11 X 12 =CX 13 (CX 14 X 15 ) n11 X 16

[0813] (where X) 11 ~X 16 Same or different, representing H, F or Cl, n11 represents an integer from 0 to 8. This excludes monomers represented by TFE and VDF, or...

[0814] Formula: CX 21 X 22 =CX 23 -O(CX 24 X 25 ) n21 X 26

[0815] (where X) 21 ~X 26 The same or different, representing H, F or Cl, n21 represents an integer from 0 to 8) indicates the monomer.

[0816] Furthermore, the third monomer can be a non-fluorinated olefinic monomer. From the perspective of maintaining heat resistance and chemical resistance, the aforementioned non-fluorinated olefinic monomer is preferably selected from olefinic monomers with 6 or fewer carbon atoms. Examples include ethylene, propylene, 1-butene, 2-butene, vinyl chloride, vinylidene chloride, alkyl vinyl ethers (methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, etc.), maleic acid, itaconic acid, 3-butenoic acid, 4-pentenoic acid, vinyl sulfonic acid, acrylic acid, methacrylic acid, etc.

[0817] In the polymerization of TFE / VDF copolymer, the above polymer (1) can be used within the scope of use in the manufacturing method of the present invention, and is usually added in an amount of 0.0001 to 5% by mass relative to 100% by mass of the aqueous medium.

[0818] The TFE / VDF copolymer obtained by polymerization can be amidated by contacting it with ammonia water, ammonia gas, or nitrogen compounds that can generate ammonia.

[0819] The TFE / VDF copolymer obtained by the above method is also preferably used as a raw material for obtaining TFE / VDF copolymer fibers by a spinning and stretching method. The above spinning and stretching method refers to the following method: the TFE / VDF copolymer is melt-spun and then cooled and solidified to obtain an unstretched filament, which is then stretched in a heated cylindrical body to obtain TFE / VDF copolymer fibers.

[0820] Alternatively, the above-mentioned TFE / VDF copolymer can be dissolved in an organic solvent to obtain a solution of the TFE / VDF copolymer. Examples of such organic solvents include nitrogen-containing organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and dimethylformamide; ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone, and methyl isobutyl ketone; ester solvents such as ethyl acetate and butyl acetate; ether solvents such as tetrahydrofuran and dioxane; and mixtures thereof, as well as other low-boiling-point general-purpose organic solvents. The above solution can be used as a battery binder.

[0821] It is also preferable to coat the aqueous dispersion of the above-mentioned TFE / VDF copolymer onto a porous substrate made of polyolefin resin to use it as a composite porous membrane. It is also preferable to disperse inorganic particles and / or organic particles in an aqueous dispersion and coat it onto a porous substrate to use it as a composite porous membrane. The resulting composite porous membrane can be used as a separator for lithium secondary batteries, etc.

[0822] The above-mentioned melt-processable fluoropolymer powders are suitable for use as powder coatings. When powder coatings composed of the above-mentioned melt-processable fluoropolymer powders are applied to a substrate, a smooth film can be obtained. Melt-processable fluoropolymer powders with an average particle size of 1 μm or more but less than 100 μm are particularly suitable as powder coatings for electrostatic coating, and melt-processable fluoropolymer powders with an average particle size of 100 μm or more but less than 1000 μm are particularly suitable as powder coatings for rotational coating or rotational molding.

[0823] The above-mentioned melt-processable fluoropolymer powder can be manufactured by drying and pulverizing the melt-processable fluoropolymer obtained by the manufacturing method of the present invention. The manufacturing method for producing the above-mentioned melt-processable fluoropolymer powder is also one aspect of the present invention.

[0824] (III) Fluororubber

[0825] In the manufacturing method of the present invention, regarding the polymerization of the above-mentioned fluororubber, pure water and the above-mentioned polymer (1) are added to a pressure-resistant reaction vessel equipped with a stirrer. After deoxygenation, monomer is added, and the temperature is brought to a predetermined temperature. A polymerization initiator is then added to initiate the reaction. Since the pressure decreases as the reaction proceeds, additional monomer is supplied continuously or intermittently to maintain the initial pressure. When a predetermined amount of monomer has been supplied, the supply is stopped, the monomer in the reaction vessel is removed, the temperature is restored to room temperature, and the reaction is terminated. In this case, the polymer emulsion can be continuously removed from the reaction vessel.

[0826] In particular, when manufacturing thermoplastic elastomers as the aforementioned fluororubbers, as disclosed in International Publication No. 00 / 01741, it is also possible to use the following method: temporarily synthesize fluoropolymer microparticles at a higher concentration, then dilute and further polymerize them, thereby accelerating the final polymerization rate compared to conventional polymerization.

[0827] In the polymerization of the aforementioned fluororubber, suitable conditions are selected based on the physical properties of the target polymer and the control of the polymerization rate. The polymerization is carried out at a temperature typically between -20 and 200°C, preferably between 5 and 150°C, and a polymerization pressure typically between 0.5 and 10 MPaG, preferably between 1 and 7 MPaG. Furthermore, the pH of the polymerization medium is preferably maintained at a typically 2.5 to 13 using known methods or pH adjusters, as described later.

[0828] Besides vinylidene fluoride, other monomers used in the polymerization of the aforementioned fluororubbers include fluorinated olefinic unsaturated monomers having at least the same number of fluorine atoms as carbon atoms and capable of copolymerizing with vinylidene fluoride. Examples of these fluorinated olefinic unsaturated monomers include trifluoropropylene, pentafluoropropylene, hexafluorobutene, and octafluorobutene. Hexafluoropropylene is particularly suitable due to the elastomer properties it produces when the polymer's crystal growth is inhibited. Other examples of these fluorinated olefinic unsaturated monomers include trifluoroethylene, TFE, and CTFE, and one or more fluorinated monomers having chlorine and / or bromine substituents can also be used. Perfluoro(alkyl vinyl ethers), such as perfluoro(methyl vinyl ethers), can also be used. TFE and HFP are preferred in the manufacture of fluororubbers.

[0829] The preferred monomer composition (mass%) of the fluororubber is vinylidene fluoride:HFP:TFE = (20–70):(30–48):(0–32), more preferably (20–70):(30–48):(0–32), and even more preferably (32–64):(30–48):(0–27). Fluororubbers with this composition exhibit good elastomer properties, chemical resistance, and thermal stability.

[0830] In the polymerization of the fluororubber described above, the polymer (1) can be used within the scope of use in the manufacturing method of the present invention, and is typically added in an amount of 0.0001 to 20% by mass relative to 100% by mass of the aqueous medium. Preferably, it is 10% by mass or less, more preferably 2% by mass or less.

[0831] In the polymerization of the aforementioned fluororubber, known inorganic free radical polymerization initiators can be used as polymerization initiators. Existing water-soluble inorganic peroxides, such as sodium, potassium, and ammonium persulfates, superphosphates, perborates, percarbonates, or permanganates, are particularly useful as these inorganic free radical polymerization initiators. These free radical polymerization initiators can also be further activated using reducing agents (e.g., sodium, potassium, or ammonium sulfites, bisulfites, metabisulfites, hyposulfites, thiosulfates, phosphites, or hypophosphites) or easily oxidized metal compounds (e.g., ferrous salts, cuprous salts, or silver salts). A suitable inorganic free radical polymerization initiator is ammonium persulfate, and more preferably, ammonium persulfate and sodium bisulfite are used simultaneously in a redox system.

[0832] The concentration of the polymerization initiator is appropriately determined based on the molecular weight of the target fluoropolymer and the polymerization reaction rate, and is set to an amount of 0.0001 to 10% by mass, preferably 0.01 to 5% by mass, relative to 100% of the total monomer amount.

[0833] In the polymerization of the aforementioned fluororubber, known substances can be used as chain transfer agents, such as hydrocarbons, esters, ethers, alcohols, ketones, chlorides, and carbonates. Hydrocarbons, esters, ethers, alcohols, chlorides, and iodides can be used in the thermoplastic elastomer. Acetone and isopropanol are preferred. In the polymerization of the thermoplastic elastomer, isopentane, diethyl malonate, and ethyl acetate are preferred from the perspective of not easily reducing the reaction rate. Diiodide compounds such as I(CF2)4I, I(CF2)6I, and ICH2I are preferred from the perspective of being able to perform iodination at the polymer ends and be used as reactive polymers.

[0834] The preferred amount of the chain transfer agent is typically 0.5 × 10⁻⁶ relative to the total amount of monomer supplied. -3 ~5×10 -3 mol% (preferably 1.0 × 10⁻⁶) -3 ~3.5×10-3 mole%.

[0835] In the polymerization of the aforementioned fluororubber, paraffin wax is preferably used as a stabilizer, and in the polymerization of thermoplastic elastomers, phosphates, sodium hydroxide, potassium hydroxide, etc. are preferably used as pH adjusters.

[0836] The fluororubber obtained by the manufacturing method of the present invention has a solid content concentration of 1.0 to 40% by mass at the time of polymerization termination, an average particle size of 0.03 to 1 μm, preferably 0.05 to 0.5 μm, and a number average molecular weight of 1,000 to 2,000,000.

[0837] The fluororubber obtained by the manufacturing method of the present invention can be formulated into a dispersion suitable for rubber molding by adding dispersing stabilizers such as hydrocarbon surfactants and concentrating as needed. The dispersion is then subjected to treatments such as pH adjustment, coagulation, and heating. Each treatment is performed as follows.

[0838] The pH adjustment mentioned above includes adding inorganic acids such as nitric acid, sulfuric acid, hydrochloric acid, or phosphoric acid, and / or carboxylic acids with 5 or fewer carbon atoms and pK = 4.2 or less, to make the pH below 2.

[0839] The aforementioned solidification is achieved by adding alkaline earth metal salts. Examples of such alkaline earth metal salts include calcium or magnesium nitrates, chlorates, and acetates.

[0840] Either the pH adjustment or the coagulation process described above can be performed first, but pH adjustment is preferred.

[0841] After each operation, the rubber is rinsed with the same volume of water as the fluororubber to remove any small amounts of buffer solution, salts, or other impurities present. Then, it is dried. Drying is typically carried out in a drying oven at a high temperature of approximately 70–200°C while air is circulated.

[0842] The aforementioned fluororubber can be either partially fluorinated rubber or perfluorinated rubber.

[0843] Examples of partially fluorinated rubbers include vinylidene fluoride (VdF) fluororubbers, tetrafluoroethylene (TFE) / propylene (Pr) fluororubbers, tetrafluoroethylene (TFE) / propylene / vinylidene fluoride (VdF) fluororubbers, ethylene / hexafluoropropylene (HFP) fluororubbers, ethylene / hexafluoropropylene (HFP) / vinylidene fluoride (VdF) fluororubbers, and ethylene / hexafluoropropylene (HFP) / tetrafluoroethylene (TFE) fluororubbers. Preferably, at least one type selected from the group consisting of vinylidene fluoride fluororubbers and tetrafluoroethylene / propylene fluororubbers is preferred.

[0844] The aforementioned vinylidene fluoride-based fluororubber is preferably a copolymer composed of 45-85 mol% vinylidene fluoride and 55-15 mol% of at least one other monomer capable of copolymerizing with vinylidene fluoride. More preferably, it is a copolymer composed of 50-80 mol% vinylidene fluoride and 50-20 mol% of at least one other monomer capable of copolymerizing with vinylidene fluoride.

[0845] Examples of other monomers capable of copolymerizing with vinylidene fluoride include: tetrafluoroethylene [TFE], hexafluoropropylene [HFP], fluoroalkyl vinyl ethers, trifluorochloroethylene [CTFE], trifluoroethylene, trifluoropropylene, pentafluoropropylene, trifluorobutylene, tetrafluoroisobutylene, hexafluoroisobutylene, fluoroethylene, and general formula (100): CH2=CFRf 101 (where Rf) 101 It is a fluorinated monomer represented by a straight-chain or branched fluoroalkyl group having 1 to 12 carbon atoms, with the general formula (170): CH2=CH-(CF2). n -X 171 (where X) 171 The monomers include fluorinated monomers (where H or F, n is an integer from 3 to 10), monomers providing crosslinking sites, and non-fluorinated monomers such as ethylene, propylene, and alkyl vinyl ethers. They can be used individually or in any combination. Among these, at least one selected from the group consisting of TFE, HFP, fluoroalkyl vinyl ethers, and CTFE is preferred. As a fluoroalkyl vinyl ether, the fluorinated monomer represented by general formula (160) is preferred.

[0846] Specific examples of vinylidene fluoride-based fluororubbers include VdF / HFP rubbers, VdF / HFP / TFE rubbers, VdF / CTFE rubbers, VdF / CTFE / TFE rubbers, VDF / fluorinated monomer rubbers of general formula (100), VDF / fluorinated monomer / TFE rubbers of general formula (100), VDF / perfluoro(methyl vinyl ether) [PMVE] rubbers, VDF / PMVE / TFE rubbers, and VDF / PMVE / TFE / HFP rubbers. Among the VDF / fluorinated monomer rubbers of general formula (100), VDF / CH2=CFCF3 rubbers are preferred; among the VDF / fluorinated monomer / TFE rubbers of general formula (100), VDF / TFE / CH2=CFCF3 rubbers are preferred.

[0847] The VDF / CH2=CFCF3 rubber is preferably a copolymer composed of 40 to 99.5 mol% VDF and 0.5 to 60 mol% CH2=CFCF3, and more preferably a copolymer composed of 50 to 85 mol% VDF and 20 to 50 mol% CH2=CFCF3.

[0848] The aforementioned tetrafluoroethylene / propylene fluororubber is preferably a copolymer composed of 45-70 mol% tetrafluoroethylene, 55-30 mol% propylene, and 0-5 mol% fluorinated monomers providing crosslinking sites.

[0849] The aforementioned fluororubber can be a perfluororubber. As the aforementioned perfluororubber, it is preferred to be a perfluororubber containing TFE, for example, preferably at least one selected from the group consisting of a fluorinated monomer copolymer of TFE / general formula (160), (130) or (140) and a monomer copolymer of TFE / general formula (160), (130) or (140) / providing a crosslinking site.

[0850] Regarding its composition, in the case of TFE / PMVE copolymer, it is preferably 45-90 / 10-55 (mol%), more preferably 55-80 / 20-45, and even more preferably 55-70 / 30-45.

[0851] When TFE / PMVE is a monomer copolymer providing crosslinking sites, the preferred composition is 45–89.9 / 10–54.9 / 0.01–4 (mol%), more preferably 55–77.9 / 20–49.9 / 0.1–3.5, and even more preferably 55–69.8 / 30–44.8 / 0.2–3.

[0852] In the case of TFE / fluorinated monomer copolymers of general formula (160), (130) or (140) having 4 to 12 carbon atoms, the preferred value is 50 to 90 / 10 to 50 (mol%), more preferably 60 to 88 / 12 to 40, and even more preferably 65 to 85 / 15 to 35.

[0853] In the case of TFE / fluorinated monomers of general formula (160), (130) or (140) having 4 to 12 carbon atoms / monomer copolymers providing crosslinking sites, the preferred ratio is 50 to 89.9 / 10 to 49.9 / 0.01 to 4 (mol%), more preferably 60 to 87.9 / 12 to 39.9 / 0.1 to 3.5, and even more preferably 65 to 84.8 / 15 to 34.8 / 0.2 to 3.

[0854] If it falls outside this composition range, it loses its properties as a rubber elastomer and tends to exhibit properties closer to those of a resin.

[0855] The perfluorinated rubber described above is preferably selected from at least one group consisting of a fluorinated monomer / fluorinated monomer copolymer of TFE / general formula (140), a perfluorinated vinyl ether copolymer of TFE / general formula (140), a fluorinated monomer copolymer of TFE / general formula (160), and a fluorinated monomer / monomer copolymer of TFE / general formula (160).

[0856] Other examples of perfluorinated rubber mentioned above include those described in International Publication No. 97 / 24381, Japanese Patent Publication No. 61-57324, Japanese Patent Publication No. 4-81608, and Japanese Patent Publication No. 5-13961.

[0857] From the perspective of excellent compression set at high temperatures, the glass transition temperature of the aforementioned fluororubber is preferably -70°C or higher, more preferably -60°C or higher, and even more preferably -50°C or higher. Furthermore, from the perspective of good cold resistance, the glass transition temperature is preferably 5°C or lower, more preferably 0°C or lower, and even more preferably -3°C or lower.

[0858] The glass transition temperature mentioned above can be determined as follows: Using a differential scanning calorimeter (manufactured by Mettler Toredo, DSC822e), a DSC curve is obtained by heating 10 mg of sample at 10 °C / min. The temperature of the midpoint between the extension of the baseline representing the second-order phase transition of the DSC curve and the tangent at the inflection point of the DSC curve is determined and taken as the glass transition temperature mentioned above.

[0859] Of the aforementioned fluororubbers, from the perspective of good heat resistance, the Mooney viscosity ML(1+20) at 170°C is preferably 30 or more, more preferably 40 or more, and even more preferably 50 or more. Furthermore, from the perspective of good processability, it is preferably 150 or less, more preferably 120 or less, and even more preferably 110 or less.

[0860] Of the aforementioned fluororubbers, from the perspective of good heat resistance, the Mooney viscosity ML(1+20) at 140°C is preferably 30 or more, more preferably 40 or more, and even more preferably 50 or more. Furthermore, from the perspective of good processability, it is preferably 180 or less, more preferably 150 or less, and even more preferably 110 or less.

[0861] Of the aforementioned fluororubbers, from the perspective of good heat resistance, the Mooney viscosity ML(1+10) at 100°C is preferably 10 or more, more preferably 20 or more, and even more preferably 30 or more. Furthermore, from the perspective of good processability, it is preferably 120 or less, more preferably 100 or less, and even more preferably 80 or less.

[0862] The Mooney viscosity described above can be measured using a Mooney viscometer MV2000E manufactured by ALPHA TECHNOLOGIES at 170°C, 140°C, or 100°C according to JIS K6300.

[0863] The fluororubber obtained by the manufacturing method of the present invention can be in any form as long as it is obtained from the above polymerization. It can be an aqueous dispersion after polymerization, or it can be used in the form of gum or crumb by precipitation, drying, etc., using existing known methods. The surfactant used in the manufacturing method of the present invention can improve the stability of the aqueous dispersion, and is more preferably used in polymerization methods in which water-poorly soluble substances such as initiators such as organic peroxides and chain transfer agents such as iodine or bromine compounds are added during polymerization as described above.

[0864] The aforementioned gum is a granular block made of fluororubber, while the aforementioned crumb is an amorphous block formed when fluororubber fails to maintain its granular form as a block at room temperature and fuses together.

[0865] The aforementioned fluororubber can be processed into fluororubber compositions by adding curing agents, fillers, etc.

[0866] Examples of curing agents include polyols, polyamines, organic peroxides, organotin compounds, bis(aminophenol)tetramine, or bis(thioaminophenol).

[0867] The above-mentioned fluororubber composition is composed of the above-mentioned fluororubber, and therefore does not contain emulsifiers in substance. It is easy to crosslink during molding and processing, which is excellent.

[0868] Fluororubber molded articles can be obtained by molding using the fluororubber described above. There are no particular limitations on the molding process described above; known methods using the curing agent described above can be cited as examples.

[0869] The aforementioned fluororubber molded bodies are suitable for use as seals, gaskets, wire sheaths, hoses, tubes, laminates, decorative products, etc., and are particularly suitable for components for semiconductor manufacturing equipment, automotive parts, etc.

[0870] The above polymerization typically yields an aqueous dispersion containing the aforementioned fluoropolymer. The fluoropolymer is typically present in the aqueous dispersion obtained by the above polymerization at a concentration of 8 to 50% by mass. The preferred lower limit of the concentration of the fluoropolymer in the aqueous dispersion is 10% by mass, more preferably 15% by mass, and the preferred upper limit is 40% by mass, more preferably 35% by mass.

[0871] The aqueous dispersion obtained by the above polymerization can be concentrated or dispersed and stabilized to form a dispersion, or it can be used for precipitation or coagulation, recovered and dried to produce the resulting powder and other solid substances.

[0872] The polymer (1) described above can also be used appropriately as a dispersant for dispersing fluoropolymers obtained by polymerization in an aqueous medium.

[0873] In the above polymerization, an aqueous dispersion containing particles made of the above-mentioned fluoropolymer, the above-mentioned polymer (1), and the above-mentioned aqueous medium is typically obtained. The above-mentioned aqueous dispersion is formed by dispersing particles made of the fluoropolymer in an aqueous medium in the presence of the above-mentioned surfactant.

[0874] The polymer (1) is preferably present in an amount of 0.0001 to 15% by mass relative to the aqueous dispersion. If the amount is less than 0.0001% by mass, the dispersion stability may deteriorate; if the amount exceeds 15% by mass, the dispersion effect will not be commensurate with the amount present, and it will be impractical. The more preferred lower limit of the surfactant is 0.001% by mass, the more preferred upper limit is 10% by mass, and the even more preferred upper limit is 2% by mass.

[0875] The aqueous dispersion can be any one of the following: an aqueous dispersion obtained by performing the above polymerization, a dispersion obtained by concentrating or dispersing and stabilizing the aqueous dispersion, or an aqueous dispersion obtained by dispersing a powder composed of a fluoropolymer in an aqueous medium in the presence of the above polymer (1).

[0876] As a method for manufacturing the above-mentioned aqueous dispersion, the aqueous dispersion obtained from the above polymerization can also be further refined by the following steps: (I) contacting the aqueous dispersion with an anion exchange resin or a mixed bed containing an anion exchange resin and a cation exchange resin in the presence of a nonionic surfactant (I); and / or, (II) concentrating the aqueous dispersion in such a way that the concentration of the solid components is 30 to 70% by mass relative to 100% by mass of the aqueous dispersion (II). The nonionic surfactant is not particularly limited, and substances described later can be used. The anion exchange resin is not particularly limited, and known substances can be used. Furthermore, the method of contacting the anion exchange resin described above can be a known method.

[0877] As a method for manufacturing the above-mentioned aqueous dispersion, the aqueous dispersion obtained from the above polymerization can be subjected to step (I), and the aqueous dispersion obtained from step (I) can be subjected to step (II) to produce a refined aqueous dispersion. Alternatively, step (II) can be performed without step (I) to produce a refined aqueous dispersion. Furthermore, steps (I) and (II) can be performed repeatedly, or they can be combined.

[0878] Examples of anion exchange resins that can be cited as having the functional group -N + X -A strongly basic anion exchange resin containing (CH3)3 group (X represents Cl or OH), and having -N + X - Well-known substances include strongly basic anion exchange resins containing the (CH3)3(C2H4OH) group (X is the same as above). Specifically, examples include substances described in International Publication No. 99 / 62858, International Publication No. 03 / 020836, International Publication No. 2004 / 078836, International Publication No. 2013 / 027850, and International Publication No. 2014 / 084399.

[0879] There are no particular limitations on the above-mentioned cation exchange resins; for example, those with the functional group -SO3 can be cited. - Strongly acidic cation exchange resins with -COO functional groups - Among known substances such as weakly acidic cation exchange resins, strong acidic cation exchange resins are preferred from the perspective of removal efficiency, and H+ is more preferred. + A strong acid cation exchange resin of the type.

[0880] The term "mixed bed containing cation exchange resin and anion exchange resin" is not particularly limited, and includes cases where both are packed in the same column, cases where both are packed in different columns, and cases where both are dispersed in an aqueous dispersion.

[0881] As a method for the aforementioned condensation, a well-known method is adopted. Specifically, methods described in International Publication No. 2007 / 046482 and International Publication No. 2014 / 084399 can be cited as examples.

[0882] Examples of methods include phase separation, centrifugal sedimentation, cloud point concentration, electroconcentration, electrophoresis, filtration using reverse osmosis (RO) membranes, and nanofiltration. The concentrations described above can be adjusted to 30–70% by mass depending on the intended use. The stability of the dispersion may be compromised by concentration, but in such cases, a dispersion stabilizer can be added. As the dispersion stabilizer, the polymer (1), the nonionic surfactant, and various other surfactants can be added. As the nonionic surfactant, the same nonionic surfactant exemplified as the nucleating agent described above can be appropriately used.

[0883] Furthermore, the cloud point of a nonionic surfactant is a measure of its solubility in water. The surfactant used in the above-mentioned aqueous dispersion has a cloud point of about 30°C to about 90°C, preferably about 35°C to about 85°C.

[0884] The total amount of the above-mentioned dispersant stabilizer is a concentration of 0.5% to 20% by mass relative to the solid content of the above-mentioned dispersion. If it is less than 0.5% by mass, the dispersion stability may deteriorate; if it exceeds 20% by mass, it does not have a dispersion effect commensurate with its amount and is not practical. A more preferred lower limit for the above-mentioned dispersant stabilizer is 2% by mass, and a more preferred upper limit is 12% by mass.

[0885] The above-described concentration process can remove the polymer (1).

[0886] The aqueous dispersion obtained by the above polymerization can be further dispersed and stabilized without concentration to prepare an aqueous dispersion with a long shelf life, depending on the intended use. Examples of the same substances as described above can be used as dispersion stabilizers.

[0887] There are no particular limitations on the uses of the above-mentioned aqueous dispersions. Direct applications of aqueous dispersions include: coatings formed by applying the dispersion to a substrate and firing it as needed after drying; impregnation formed by impregnating a porous support such as nonwoven fabric or resin molded article and firing it after drying; and casting formed by coating the dispersion to a substrate such as glass, immersing it in water as needed after drying, and peeling off the substrate to obtain a film. Examples of these applications include aqueous dispersion coatings, tent films, conveyor belts, printed circuit boards (CCLs), electrode adhesives, and electrode waterproofing agents.

[0888] The above-mentioned aqueous dispersion can be used as a water-based coating by mixing with known pigments, thickeners, dispersants, defoamers, antifreeze agents, film-forming aids and other compounding agents, or by further compounding with other polymer compounds.

[0889] In addition, as an additive, it can be used as a binder to suppress the shedding of active material from electrodes, as an anti-drip agent, and as a dust suppression treatment to prevent sand or dust from flying.

[0890] To adjust the viscosity of the aforementioned aqueous dispersion or to improve the miscibility of pigments, fillers, etc., anionic surfactants are preferably included. Anionic surfactants can be added appropriately within limits where there are no economic or environmental concerns.

[0891] Examples of anionic surfactants include non-fluorinated anionic surfactants and fluorinated anionic surfactants, with non-fluorinated anionic surfactants that do not contain fluorine, i.e., hydrocarbon anionic surfactants, being preferred.

[0892] For the purpose of adjusting viscosity, any known anionic surfactant can be used, regardless of the type. For example, anionic surfactants described in International Publication Nos. 2013 / 146950 and 2013 / 146947 can be used. Examples include anionic surfactants having saturated or unsaturated aliphatic chains with 6 to 40 carbon atoms, preferably 8 to 20, and more preferably 9 to 13 carbon atoms. The saturated or unsaturated aliphatic chains can be straight-chain or branched, and can also have a cyclic structure. The hydrocarbon can be aromatic or contain aromatic groups. The hydrocarbon can also contain heteroatoms such as oxygen, nitrogen, and sulfur.

[0893] Examples of anionic surfactants include alkyl sulfonates, alkyl sulfates, alkyl aryl sulfates and their salts; aliphatic (carboxylic) acids and their salts; alkyl phosphates, alkyl aryl phosphates or their salts; and so on, with alkyl sulfonates, alkyl sulfates, aliphatic carboxylic acids or their salts being preferred.

[0894] As an alkyl sulfate or its salt, ammonium lauryl sulfate or sodium lauryl sulfate are preferred.

[0895] As an aliphatic carboxylic acid or its salt, succinic acid, decanoic acid, undecanoic acid, undecenoic acid, lauric acid, hydrogen dodecanoic acid or their salts are preferred.

[0896] The amount of anionic surfactant added also depends on the type of anionic surfactant or other compounding agent, preferably 10 ppm to 5000 ppm relative to the solid component of the fluoropolymer.

[0897] The lower limit for the amount of anionic surfactant added is preferably 50 ppm or more, and even more preferably 100 ppm or more. If the amount added is too small, the viscosity-adjusting effect will be insufficient.

[0898] The upper limit for the amount of anionic surfactant added is preferably 3000 ppm or less, and more preferably 2000 ppm or less. If the amount added is too high, the mechanical stability and storage stability of the aqueous dispersion may be impaired.

[0899] In order to adjust the viscosity of the above-mentioned aqueous dispersion, in addition to anionic surfactants, other substances such as methylcellulose, alumina sol, polyvinyl alcohol, and carboxylated vinyl polymers can also be mixed.

[0900] For the purpose of adjusting the pH of the above aqueous dispersion, a pH adjuster such as ammonia can also be mixed in.

[0901] In the above-mentioned aqueous dispersion, other water-soluble polymeric compounds may be contained within a range that does not impair the characteristics of the aqueous dispersion, if necessary.

[0902] Other water-soluble polymers mentioned above are not particularly limited, and examples include polyethylene oxide (dispersion stabilizer), polyethylene glycol (dispersion stabilizer), polyvinylpyrrolidone (dispersion stabilizer), phenolic resin, urea resin, epoxy resin, melamine resin, polyester resin, polyether resin, acrylic silicone resin, silicone resin, silicone polyester resin, polyurethane resin, etc. In addition, it may also contain isothiazolone compounds, azole compounds, bropol, chlorothalonil, methylsulfonyltetrachloropyridine, carbendazim, 2-[(dichlorofluoromethyl)-thio]-1H-isoindole-1,3-(2H)-dione (Fluor Folpet), sodium diacetate, diiodomethyl-p-tolyl sulfone, etc., as preservatives.

[0903] The polymer (1), decomposition products or byproducts of polymer (1) and residual monomers generated by the above-mentioned precipitation or washing and / or waste gas generated by the drying process are recovered and purified from the wastewater generated by the above-mentioned precipitation or washing and / or waste gas generated by the drying process. This allows for the reuse of the polymer (1), the decomposition products or byproducts of polymer (1) and residual monomers. There are no particular limitations on the method for performing the above-mentioned recovery and purification; known methods can be used. For example, the method described in Japanese Patent Publication No. 2011-520020 can be used.

[0904] There are no particular limitations on the method for recovering and refining the polymer (1) from the wastewater generated by the above precipitation, the wastewater generated by the washing process, and the exhaust gas generated by the drying process, as well as the decomposition products or byproducts of the polymer (1) byproducts and residual monomers. Existing known methods can be used, and examples include the methods described in U.S. Patent Application Publication No. 2007 / 0015937, U.S. Patent Application Publication No. 2007 / 0025902, and U.S. Patent Application Publication No. 2007 / 0027251. Specifically, the following methods can be cited.

[0905] As a method for recovering polymer (1), decomposition products or byproducts of polymer (1) byproducts, residual monomers, etc. from the above-mentioned wastewater, the following method can be cited: the wastewater is contacted with adsorbent particles such as ion exchange resin, activated carbon, silica gel, clay, zeolite, etc., to adsorb the above-mentioned polymer (1), etc., and then the wastewater and adsorbent particles are separated. If the adsorbent particles adsorbed with the above-mentioned polymer (1), etc. are incinerated, the release of the above-mentioned polymer (1), etc. into the environment can be prevented.

[0906] Alternatively, known methods can be used to detach and dissolve the aforementioned polymer (1) from the ion exchange resin particles on which the polymer (1) is adsorbed, and then recover it. For example, if the ion exchange resin particles are anion exchange resin particles, the polymer (1) can be dissolved by contacting an inorganic acid with the anion exchange resin. When a water-soluble organic solvent is subsequently added to the resulting leachate, it usually separates into two phases. Therefore, the polymer (1) can be recovered by recovering the lower phase containing the polymer (1) and neutralizing it. Examples of such water-soluble organic solvents include polar solvents such as alcohols, ketones, and ethers.

[0907] Other methods for recovering the aforementioned polymer (1) from ion exchange resin particles include methods using ammonium salts and water-soluble organic solvents, and methods using alcohols and desired acids. In the latter method, since ester derivatives of the polymer (1) are generated, it can be easily separated from the alcohol by distillation.

[0908] In cases where the wastewater contains fluoropolymer particles or other solid components, it is preferable to remove them before the wastewater comes into contact with the adsorbed particles. Methods for removing fluoropolymer particles and other solid components include methods such as adding aluminum salts to precipitate them and then separating the wastewater from the precipitate, and electrocoagulation. Alternatively, mechanical methods can be used for removal, such as cross-flow filtration, depth filtration, and pre-coating filtration.

[0909] From a productivity perspective, it is preferable to have a low concentration of the aforementioned uncoagulated fluoropolymers in the wastewater, more preferably less than 0.4% by mass, and particularly preferably less than 0.3% by mass.

[0910] As a method for recovering the polymer (1) and the like from the aforementioned waste gas, one example is to use a scrubber to contact the waste gas with organic solvents such as deionized water, alkaline aqueous solution, or glycol ether solvent to obtain a scrubbing gas solution containing surfactants. When a high-concentration alkaline aqueous solution is used as the alkaline aqueous solution, the scrubbing gas solution can be recovered while the polymer (1) and the like are in a phase-separated state, thus facilitating the recovery and reuse of the polymer (1) and the like. Examples of alkaline compounds include alkali metal hydroxides and quaternary ammonium salts.

[0911] The scrubbing gas solution containing the polymer (1) can be concentrated using a reverse osmosis membrane or similar method. The concentrated scrubbing gas solution usually contains fluoride ions, but these fluoride ions can be removed by further adding alumina after concentration, making it easy to reuse the polymer (1). Alternatively, adsorbent particles can be brought into contact with the scrubbing gas solution to adsorb the polymer (1), and the polymer (1) can be recovered by the above method.

[0912] Polymers (1) recovered by any of the above methods can be reused in the manufacture of fluoropolymers.

[0913] In addition, the present invention relates to a use for manufacturing a polymer of a fluoropolymer by polymerizing a fluoropolymer in an aqueous medium, characterized in that the polymer is a polymer (1) comprising a polymerization unit (1) based on a monomer represented by the following general formula (1).

[0914] CX2=CY(-CZ2-O-Rf-A) (1)

[0915] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0916] The aqueous medium, the fluorinated monomer, and the fluorinated polymer described above are preferably the same substances that can be used in the manufacturing method of the present invention. The suitable composition of the polymer (1) described above is the same as that of the polymer (1) used in the manufacturing method of the present invention.

[0917] In addition, the present invention relates to a composition characterized in that it contains a fluoropolymer and a polymer (1) comprising a polymeric unit (1) based on a monomer represented by the following general formula (1).

[0918] CX2=CY(-CZ2-O-Rf-A) (1)

[0919] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).) 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0920] In the composition of the present invention, the polymerization unit (1) is preferably a polymerization unit (1A) based on the monomer shown in the following general formula (1A).

[0921] CH2=CF(-CF2-O-Rf-A)(1A)

[0922] (In the formula, Rf and A are the same as above.)

[0923] The fluoropolymer described above may be different from the polymer (1) described above. Preferably, it is the same as the substance that can be used in the manufacturing method of the present invention. More preferably, it is a fluoropolymer. More preferably, it is a fluoropolymer with a fluorine substitution rate of 50% or more. More preferably, it is a fluoropolymer with a fluorine substitution rate of more than 50%. More preferably, it is a fluoropolymer with a fluorine substitution rate of 55% or more. More preferably, it is a fluoropolymer with a fluorine substitution rate of 60% or more. More preferably, it is a fluoropolymer with a fluorine substitution rate of 75% or more. Particularly preferred, it is a fluoropolymer with a fluorine substitution rate of 80% or more. Most preferably, it is a fluoropolymer with a fluorine substitution rate of 90 to 100%, i.e., a perfluorinated resin.

[0924] As the aforementioned perfluorinated resin, a fluorinated resin with a fluorine substitution rate of 95-100% is more preferred, PTFE, FEP, and PFA are even more preferred, and PTFE is particularly preferred.

[0925] That is, in the above composition, the fluoropolymer is preferably polytetrafluoroethylene (PTFE). Furthermore, from the perspective of the stability and yield of the aqueous dispersion, the PTFE is more preferably modified PTFE.

[0926] The suitable composition of the polymer (1) is the same as that of the polymer (1) used in the manufacturing method of the present invention.

[0927] The composition of the present invention can be an aqueous dispersion, a powder, or granules. The aqueous dispersion can be a polymerized dispersion or a substance obtained by processing a polymerized dispersion. For example, nonionic surfactants can be added for mechanical stability and storage stability. When the aforementioned nonionic surfactant is added, its amount relative to the aforementioned fluoropolymer is preferably 0.5 to 25% by mass. A further preferred lower limit is 1% by mass, an even more preferred lower limit is 3% by mass, a more preferred upper limit is 20% by mass, a further preferred upper limit is 15% by mass, and an even more preferred upper limit is 10% by mass.

[0928] An aqueous dispersion refers to a dispersion system in which an aqueous medium is used as the dispersion medium and the aforementioned fluoropolymer is used as the dispersed phase. The aqueous medium is not particularly limited as long as it is a liquid containing water; in addition to water, it may also contain organic solvents such as alcohols, ethers, ketones, and paraffin wax.

[0929] The lower limit of the content of the polymer (1) in the above composition is preferably 0.0001% by mass, more preferably 0.001% by mass, further preferably 0.01% by mass, and particularly preferably 0.1% by mass relative to the fluoropolymer. The upper limit is preferably 20% by mass, more preferably 10% by mass, further preferably 6% by mass, 4% by mass, and even more preferably 2% by mass or less, particularly preferably 1.5% by mass or less, and most preferably 1% by mass or less.

[0930] In this specification, the content of the above polymer (1) is determined by solid-state NMR measurement.

[0931] In addition, methods for determining the content of the aforementioned polymer (1) are described in International Publication No. 2014 / 099453, International Publication No. 2010 / 075497, International Publication No. 2010 / 075496, International Publication No. 2011 / 008381, International Publication No. 2009 / 055521, International Publication No. 1987 / 007619, Japanese Patent Application Publication No. 61-293476, International Publication No. 2010 / 075494, International Publication No. 2010 / 075359, International Publication No. 2012 / 082454, International Publication No. 2006 / 119224, and International Publication No. 2013 / 0858. Methods for determining various polymers described in Japanese Patent Application Publication No. 64, International Publication No. 2012 / 082707, International Publication No. 2012 / 082703, International Publication No. 2012 / 082454, International Publication No. 2012 / 082451, International Publication No. 2006 / 135825, International Publication No. 2004 / 067588, International Publication No. 2009 / 068528, Japanese Patent Application Publication No. 2004-075978, Japanese Patent Application Publication No. 2001-226436, International Publication No. 1992 / 017635, International Publication No. 2014 / 069165, and Japanese Patent Application Publication No. 11-181009, etc.

[0932] The content of the polymer (1) in the above composition can be, for example, determined by solid-state... 19 The determination was obtained by F-MAS NMR.

[0933] As specific devices, Bruker's AVANCE III HD400 and AVANCE 300, etc., can be used.

[0934] The rotational speed is set according to the resonant frequency of the device, and is set so that the rotating sideband does not overlap with the peak used in the calculation of the content of the fluoropolymer or the polymer (1).

[0935] The present invention also relates to molded articles composed of the above-described composition. The molded article is preferably a stretched article. Examples of stretched articles include, but are not limited to, filaments, tubes, belts, and films (uniaxial stretched films, biaxial stretched films).

[0936] The composition of the present invention preferably uses polytetrafluoroethylene as the fluoropolymer.

[0937] The following provides a more detailed description of the case where the fluoropolymer in the composition of the present invention is polytetrafluoroethylene.

[0938] The composition of the present invention is a composition comprising polytetrafluoroethylene and polymer (1). The content of polymer (1) is preferably 0.0001% by mass or more and 20% by mass or less relative to polytetrafluoroethylene. In the composition of the present invention, the lower limit of the content of polymer (1) relative to polytetrafluoroethylene is more preferably 0.001% by mass, further preferably 0.01% by mass, and particularly preferably 0.1% by mass. The upper limit is more preferably 10% by mass, further preferably 6% by mass, even more preferably 4% by mass, particularly preferably 2% by mass or less, particularly preferably 1.5% by mass or less, and most preferably 1% by mass or less.

[0939] The content of the above polymer (1) was determined by solid-state NMR.

[0940] For example, if the polymer (1) in the above composition is a copolymer of TFE and the monomer shown in CH2=CF(CF2OCFCF3COONH4), when determining the content of the copolymer of TFE and the monomer shown in CH2=CF(CF2OCFCF3COONH4) in the composition, the rotation speed can be set to 30 kHz when using the AVANCE300 manufactured by Bruker Japan Co., Ltd.

[0941] For example, if the polymer (1) in the above composition is a copolymer of TFE and the monomer shown in CH2=CF(CF2OCFCF3COONH4), the content of the copolymer of TFE and the monomer shown in CH2=CF(CF2OCFCF3COONH4) in the composition can be determined by the following formula from the solid state. 19 The spectrum was obtained from F-MAS NMR measurement (rotation speed 30 kHz).

[0942] Y = (400B / (5×A+3×B))×100

[0943] Y: Content (mol%) of the copolymer of TFE and the monomers shown in CH2=CF(CF2OCFCF3COONH4).

[0944] A: The integral value of a signal of -120ppm

[0945] B: The sum of the integral values ​​of the CF2 and CF3 signals at -83ppm

[0946] The chemical shift value is the value when the peak of the signal from the PTFE backbone is set to -120 ppm.

[0947] x: The proportion (mol%) of polymeric units based on the monomer shown in CH2=CF(CF2OCFCF3COONH4) in the copolymer of TFE and the monomer shown in CH2=CF(CF2OCFCF3COONH4).

[0948] In the composition of the present invention, the total amount of polytetrafluoroethylene and polymer (1) is preferably 90% by mass or more, more preferably 99% by mass or more, and even more preferably substantially 100% by mass.

[0949] In the composition of the present invention, polytetrafluoroethylene is more preferably modified polytetrafluoroethylene.

[0950] The aspect ratio of the primary polytetrafluoroethylene particles is preferably less than 2.00, more preferably 1.90 or less, even more preferably 1.80 or less, even more preferably 1.70 or less, particularly preferably 1.60 or less, and especially preferably 1.50 or less. The aspect ratio is more preferably 1.45 or less, even more preferably 1.40 or less, even more preferably 1.35 or less, especially preferably 1.30 or less, particularly preferably 1.20 or less, and most preferably 1.10 or less.

[0951] In the case of determination in an aqueous dispersion, the above length and width ratios are obtained as follows: using a scanning electron microscope (SEM) to observe an aqueous dispersion of PTFE diluted to a solid component concentration of about 1% by mass, image processing is performed on more than 400 randomly selected particles, and the ratio of their major axis to minor axis is used to determine the length and width ratios.

[0952] In the case of powder measurement, the above aspect ratio is obtained as follows: After irradiating PTFE powder with electron beams, it is added to an aqueous solution of a fluorinated surfactant and redispersed using ultrasound, thereby obtaining an aqueous PTFE dispersion. The aspect ratio is then determined from this aqueous PTFE dispersion using the same method as that used for measurement with the above aqueous dispersion.

[0953] The compositions of the present invention are also suitable for use as materials for forming stretched bodies (stretching materials). That is, the compositions of the present invention are preferably capable of being stretched.

[0954] The composition of the present invention preferably has a polymer (1) content of 0.0001% by mass or more and 20% by mass or less relative to polytetrafluoroethylene, and is capable of stretching.

[0955] When used as a stretching material, the composition of the present invention is preferably in the form of a powder.

[0956] In this instruction manual, "able to stretch" means that the following criteria are used to determine this.

[0957] Add 21.7g of lubricant (trade name: Isopar H (registered trademark), manufactured by Exxon) to 100g of PTFE powder and mix for 3 minutes at room temperature in a glass bottle. Next, before extrusion, leave the glass bottle at room temperature (25°C) for at least 1 hour to obtain lubricating resin. Extrude the lubricating resin through an orifice (2.5mm diameter, 11mm blade length, 30° inlet angle) at room temperature with a 100:1 reduction ratio to obtain uniform beads. Set the extrusion speed, i.e., the stamping speed, to 20 inches / minute (51cm / minute). Heat the beads obtained by extrusion at 230°C for 30 minutes to remove the lubricant from the beads. Next, cut the beads (extruded bodies) to appropriate lengths, secure the ends to the chucks with a chuck spacing of 1.5 inches (38mm), and heat to 300°C in an air-circulating oven. Next, the clamps are separated at the desired speed (elongation rate) to a separation distance equivalent to the desired elongation (total elongation), and an elongation test is performed. This elongation method is essentially the same as that disclosed in U.S. Patent No. 4,576,869, except for the extrusion speed (51 cm / min instead of 84 cm / min). "Elongation" refers to the increase in length caused by stretching, usually expressed in relation to the original length. In the above manufacturing method, the elongation rate is 1000% / second, and the total elongation is 2400%. This means that no beads were cut during the stretching test, resulting in stretched beads with a uniform appearance.

[0958] The standard specific gravity (SSG) of the composition of the present invention is preferably 2.200 or less. By setting the standard specific gravity to 2.200 or less, a composition capable of stretching can be formed, and a tensile body with excellent breaking strength can also be obtained. The above-mentioned standard specific gravity is preferably 2.195 or less, more preferably 2.190 or less, and even more preferably 2.185 or less.

[0959] The above standard specific gravity was determined using samples molded according to ASTM D4895-89 by the water displacement method according to ASTM D-792.

[0960] The extrusion pressure of the composition of the present invention is preferably 30.0 MPa or less, more preferably 25.0 MPa or less, more preferably 5.0 MPa or more, and more preferably 10.0 MPa or more. The above-mentioned extrusion pressure is a value obtained by means of the method described in Japanese Patent Application Publication No. 2002-201217.

[0961] Add 21.7g of lubricant (trade name: Isopar H (registered trademark), manufactured by Exxon) to 100g of PTFE powder and mix for 3 minutes at room temperature in a glass bottle. Next, before extrusion, leave the glass bottle at room temperature (25°C) for at least 1 hour to obtain lubricated resin. Extrude the lubricated resin through an orifice (2.5mm diameter, 11mm blade length, 30° inlet angle) at room temperature with a reduction ratio of 100:1 to obtain uniform beads (beadings). The extrusion speed, i.e., the punching speed, is set to 20 inches / minute (51cm / minute). The extrusion pressure is obtained by dividing the load at which the extrusion load reaches equilibrium during paste extrusion by the cross-sectional area of ​​the barrel used in the paste extrusion.

[0962] The tensile strength of the composition of the present invention is preferably 10.0 N or more. Preferably, the composition of the present invention has a tensile strength of 10.0 N or more when the content of polymer (1) is 0.0001% by mass or more and 20% by mass or less relative to polytetrafluoroethylene.

[0963] The fracture strength is more preferably 13.0 N or more, further preferably 16.0 N or more, and even more preferably 19.0 N or more. The higher the fracture strength, the better, and the upper limit of the fracture strength is, for example, 50.0 N.

[0964] The fracture strength mentioned above was obtained using the following method.

[0965] First, tensile tests were conducted on the extruded beads using the following method to prepare samples for determining their fracture strength.

[0966] The beads obtained by extruding the above-described paste are heated at 230°C for 30 minutes to remove the lubricant from the beads. Next, the beads (extruded bodies) are cut to appropriate lengths, and each end is secured to a chuck at 1.5-inch (38 mm) intervals. The chucks are then heated to 300°C in an air-circulating oven. Next, the chucks are separated at a desired speed (elongation rate) to a separation distance commensurate with the desired elongation (total elongation), and an elongation test is performed. This elongation method is essentially the same as that disclosed in U.S. Patent No. 4,576,869, except for the extrusion speed (51 cm / min instead of 84 cm / min). "Elongation" refers to the increase in length caused by stretching, usually expressed in relation to the original length. In the above manufacturing method, the elongation rate is 1000% / second, and the total elongation is 2400%.

[0967] For the tensile beads obtained in the above tensile test (made by elongating beads), they are clamped and fixed in the movable jaws of a gauge with a length of 5.0 cm, and a tensile test is performed at 25°C at a speed of 300 mm / min. The strength at break is taken as the breaking strength.

[0968] The stress relaxation time of the composition of the present invention is preferably 50 seconds or more, more preferably 80 seconds or more, even more preferably 100 seconds or more, and may also be 150 seconds or more. The above-mentioned stress relaxation time is a value measured by the method described below.

[0969] The two ends of the tensile beads obtained in the above tensile test were connected to a fixing tool to form a taut bead sample with a total length of 8 inches (20 cm). The oven was maintained at 390°C, and the fixing tool was inserted into the oven through a slit located on the side (covered). The time required from the moment of insertion into the oven until the bead sample broke was defined as the stress relaxation time.

[0970] The compositions of the present invention preferably do not substantially contain fluorinated surfactants. In this specification, "substantially do not contain fluorinated surfactants" means that the fluorinated surfactant content is 10 ppm or less relative to the fluorinated polymer. The content of the fluorinated surfactant is preferably 1 ppm or less, more preferably 100 ppb or less, even more preferably 10 ppb or less, even more preferably 1 ppb or less, and particularly preferably below the detection limit as determined by liquid chromatography-mass spectrometry (LC / MS / MS).

[0971] The amount of the aforementioned fluorinated surfactant can be quantified using known methods. For example, it can be quantified by LC / MS / MS analysis. First, the obtained aqueous dispersion, powder, molded body, granules, or fluorinated polymer formed by micronizing the molded body or fluorinated polymer formed by micronizing the granules is extracted into an organic solvent of methanol. For the extract, the molecular weight information is selected by LC / MS / MS spectroscopy to confirm that it is consistent with the structural formula of the candidate surfactant.

[0972] Subsequently, aqueous solutions of the identified surfactants at concentrations of five or more were prepared, and LC / MS / MS analyses were performed at each concentration to generate calibration curves based on the area of ​​the region.

[0973] The obtained aqueous dispersion, powder, or powder obtained by pulverizing the molded body is subjected to Soxhlet extraction with methanol, and the extract is analyzed by LC / MS / MS, thereby enabling quantitative determination.

[0974] The fluorinated surfactant described above is the same as the substance exemplified in the manufacturing method of the present invention. For example, it can be a surfactant containing fluorine atoms in which the total number of carbon atoms in the portion excluding the anionic group is 20 or less, a fluorinated surfactant containing fluorine in which the molecular weight of the anionic portion is 800 or less, or a fluorinated surfactant containing fluorine with a LogPOW of 3.5 or less.

[0975] Examples of anionic fluorinated surfactants include those with the general formula (N... 0 The compounds shown in the figure, specifically, those with the general formula (N) can be cited. 1 The compound shown in the figure, general formula (N) 2 The compound shown in the figure, general formula (N) 3 The compound shown in the figure, general formula (N) 4 The compounds shown in the figure and the general formula (N) 5 The compounds shown in the formula are as follows. More specifically, examples include perfluorocarboxylic acids (I) of general formula (I), ω-H perfluorocarboxylic acids (II) of general formula (II), perfluoropolyether carboxylic acids (III) of general formula (III), perfluoroalkylalkylene carboxylic acids (IV) of general formula (IV), perfluoroalkoxyfluorocarboxylic acids (V) of general formula (V), perfluoroalkylsulfonic acids (VI) of general formula (VI), ω-H perfluorosulfonic acids (VII) of general formula (VII), perfluoroalkylalkylene sulfonic acids (VIII) of general formula (VIII), alkylalkylene carboxylic acids (IX) of general formula (IX), fluorocarboxylic acids (X) of general formula (X), alkoxyfluorosulfonic acids (XI) of general formula (XI), and compounds (XII) of general formula (XII).

[0976] The present invention also provides a stretchable body obtained by stretching the above-described composition. The stretching can be performed using existing, well-known PTFE stretching methods and conditions, and is not limited thereto.

[0977] The present invention also provides a tensile body, characterized in that it contains a fluoropolymer and a polymer (1) comprising a polymeric unit (1) having a tensile strength of 10.0 N or more, wherein the polymeric unit (1) is based on a monomer represented by the following general formula (1).

[0978] CX2=CY(-CZ2-O-Rf-A) (1)

[0979] (In the formula, X may be the same or different, and is -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and is -H, -F, alkyl, or fluoroalkyl. Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms. A is -COOM, -SO3M, or -OSO3M (M is -H, a metal atom, or -NR).)7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or organic group. At least one of X, Y, and Z contains a fluorine atom.

[0980] In the stretching body of the present invention, polytetrafluoroethylene and polymer (1) are the same substances as those described in the composition of the present invention, and can be used in preferred manner.

[0981] The tensile strength of the tensile body of the present invention is more preferably 13.0 N or more, further preferably 16.0 N or more, and even more preferably 19.0 N or more. The higher the tensile strength, the better; the upper limit of the tensile strength is, for example, 50.0 N.

[0982] Regarding the fracture strength of the tensile body, the tensile body was clamped and fixed in the movable jaw of a gauge with a length of 5.0 cm, and a tensile test was performed at 25°C at a speed of 300 mm / min. The strength at fracture was taken as the fracture strength.

[0983] The stress relaxation time of the tensile body of the present invention is preferably 50 seconds or more, more preferably 80 seconds or more, even more preferably 100 seconds or more, and may also be 150 seconds or more. The above-mentioned stress relaxation time is a value measured using the method described below.

[0984] Regarding the stress relaxation time of the tensile specimen, the two ends of the tensile specimen were connected to a fixing tool to form a sample with a total length of 8 inches (20 cm) under tension. The oven was maintained at 390°C, and the fixing tool was inserted into the oven through a slit located on the side (covered). The stress relaxation time is defined as the time required from the moment of insertion into the oven until the sample breaks.

[0985] The endothermic peak temperature of the stretched body of the present invention is preferably between 325 and 350°C. Furthermore, the endothermic peak temperature of the stretched body of the present invention is preferably between 325 and 350°C and between 360 and 390°C. The aforementioned endothermic peak temperature corresponds to the maximum value in the heat of fusion curve when the stretched body is heated at a rate of 10°C / minute using a differential scanning calorimeter (DSC).

[0986] The porosity of the stretched body of the present invention is preferably in the range of 30% to 99%. More preferably, it is 40% or more; even more preferably, 50% or more; still more preferably, 60% or more; and particularly preferably, 70% or more. If the proportion of PTFE in the stretched body is too small, the strength of the stretched body may be insufficient; therefore, the porosity is preferably 95% or less, more preferably 90% or less.

[0987] The porosity of a stretched body can be calculated using the apparent density ρ by the following formula.

[0988] Porosity (%) = [(2.2 - ρ) / 2.2] × 100

[0989] In the above formula, 2.2 is the true density of PTFE (g / cm³). 3 ).

[0990] Regarding the density ρ of the above-mentioned tensile body, when the tensile body is in the form of a film or sheet, the mass of a sample cut into a specific size is measured using a precision balance, and the density of the sample is calculated from the measured mass of the sample and the film thickness using the following formula.

[0991] ρ=M / (4.0×12.0×t)

[0992] ρ = density (membrane density) (g / cm3)

[0993] M = mass (g)

[0994] t=Film thickness (cm)

[0995] The above measurements and calculations were performed at the three locations, and their average value was taken as the membrane density.

[0996] Regarding film thickness, a film thickness gauge is used to overlap 5 stretched bodies and measure the overall film thickness. Divide the value by 5 to obtain the film thickness of 1 sheet.

[0997] When the tensile body is cylindrical, the density ρ of the tensile body is determined by measuring the mass of a sample cut to a certain length using a precision balance. The density of the sample is then calculated using the following formula based on the measured mass and outer diameter of the sample.

[0998] ρ=M / (r×r×π)×L

[0999] ρ = density (g / cm3)

[1000] M = mass (g)

[1001] r = radius (cm)

[1002] L = Length (cm)

[1003] π = Pi

[1004] The outer diameter of the stretched body was measured using a laser displacement sensor. The radius was obtained by dividing this value by 2.

[1005] The above measurements and calculations were performed at the three locations, and their average value was taken as the density.

[1006] The preferred content of polymer (1) in the stretchable body of the present invention is 0.0001% by mass or more and 20% by mass or less relative to polytetrafluoroethylene. In the stretchable body of the present invention, the lower limit of the content of polymer (1) relative to polytetrafluoroethylene is more preferably 0.001% by mass, further preferably 0.01% by mass, and particularly preferably 0.1% by mass. The upper limit is more preferably 10% by mass, further preferably 6% by mass, even more preferably 4% by mass, particularly preferably 2% by mass or less, particularly preferably 1.5% by mass or less, and most preferably 1% by mass or less.

[1007] The content of the above polymer (1) was determined by solid-state NMR.

[1008] The stretched body of the present invention preferably does not substantially contain fluorinated surfactants. In this specification, "substantially does not contain fluorinated surfactants" means that the fluorinated surfactant content is 10 ppm or less relative to the fluorinated polymer. The content of the fluorinated surfactant is preferably 1 ppm or less, more preferably 100 ppb or less, even more preferably 10 ppb or less, even more preferably 1 ppb or less, and particularly preferably below the detection limit as determined by liquid chromatography-mass spectrometry (LC / MS / MS).

[1009] The amount of the fluorinated surfactant mentioned above can be quantified using known methods. For example, it can be quantified by LC / MS / MS analysis. First, the micronized stretched body is extracted into an organic solvent of methanol. For the extract, the molecular weight information is selected by LC / MS / MS spectroscopy to confirm that it is consistent with the structural formula of the candidate surfactant.

[1010] Subsequently, aqueous solutions of the identified surfactants at concentrations of five or more were prepared, and LC / MS / MS analyses were performed at each concentration to generate calibration curves based on the area of ​​the region.

[1011] The powder obtained by pulverizing the stretched body was subjected to Soxhlet extraction with methanol, and the extract was analyzed by LC / MS / MS, which allowed for quantitative determination.

[1012] The fluorinated surfactant described above is the same as the substance exemplified in the manufacturing method of the present invention. For example, it can be a surfactant containing fluorine atoms in which the total number of carbon atoms in the portion excluding the anionic group is 20 or less, a fluorinated surfactant containing fluorine in which the molecular weight of the anionic portion is 800 or less, or a fluorinated surfactant containing fluorine with a LogPOW of 3.5 or less.

[1013] Examples of anionic fluorinated surfactants include those with the general formula (N... 0 The compounds shown in the figure, specifically, those with the general formula (N) can be cited. 1The compound shown in the figure, general formula (N) 2 The compound shown in the figure, general formula (N) 3 The compound shown in the figure, general formula (N) 4 The compounds shown in the figure and the general formula (N) 5 The compounds shown in the formula are as follows. More specifically, examples include perfluorocarboxylic acids (I) of general formula (I), ω-H perfluorocarboxylic acids (II) of general formula (II), perfluoropolyether carboxylic acids (III) of general formula (III), perfluoroalkylalkylene carboxylic acids (IV) of general formula (IV), perfluoroalkoxyfluorocarboxylic acids (V) of general formula (V), perfluoroalkylsulfonic acids (VI) of general formula (VI), ω-H perfluorosulfonic acids (VII) of general formula (VII), perfluoroalkylalkylene sulfonic acids (VIII) of general formula (VIII), alkylalkylene carboxylic acids (IX) of general formula (IX), fluorocarboxylic acids (X) of general formula (X), alkoxyfluorosulfonic acids (XI) of general formula (XI), and compounds (XII) of general formula (XII).

[1014] The stretchable body of the present invention can be obtained by stretching the composition of the present invention.

[1015] The stretching body of the present invention is preferably in the shape of a membrane, tube, fiber, or rod.

[1016] When the stretching body of the present invention is a membrane (stretched membrane or porous membrane), it can be stretched using a known PTFE stretching method.

[1017] Preferably, a uniaxially stretched film can be obtained by roller stretching the sheet or rod-shaped paste extrudate along the extrusion direction.

[1018] In addition, biaxially oriented films can also be obtained by stretching along the width direction using a tenter frame or similar equipment.

[1019] It is also preferable to perform a semi-firing process before stretching.

[1020] The stretchable body of the present invention is a porous body with high porosity, which can be appropriately used as filter material for various precision filters such as air filters and reagent filters, and as a support material for polymer electrolyte membranes.

[1021] In addition, it is also useful as a material for products used in the fields of fibers, medicine, electrochemistry, sealing materials, air filtration, ventilation / internal pressure regulation, liquid filtration, and general consumables.

[1022] The following examples illustrate specific uses.

[1023] Electrochemistry

[1024] Dielectric prepregs, EMI shielding materials, heat transfer materials, etc. More specifically, printed circuit boards, electromagnetic shielding materials, insulating and heat transfer materials, insulating materials, etc.

[1025] Sealing materials field

[1026] Gaskets, sealing gaskets, pump diaphragms, pump tubing, sealing materials for aircraft, etc.

[1027] air filtration field

[1028] ULPA filters (for semiconductor manufacturing), HEPA filters (for hospitals and semiconductor manufacturing), cylindrical cartridge filters (for industrial use), bag filters (for industrial use), heat-resistant bag filters (for exhaust gas treatment), heat-resistant pleated filters (for exhaust gas treatment), SINBRAN filters (for industrial use), catalytic filters (for exhaust gas treatment), filters with adsorbents (for HDD assembly), air filters with adsorbents (for HDD assembly), air filters (for HDD assembly, etc.), vacuum cleaner filters (for vacuum cleaners), general-purpose multi-layer felt, GT cartridge filters (for interchangeable parts suitable for GT), cooling filters (for electronic device housings), etc.

[1029] Ventilation / Internal Pressure Adjustment

[1030] Freeze-drying materials such as freeze-drying containers; automotive ventilation materials suitable for electronic circuits or lights; container applications such as container lids; protective ventilation applications suitable for electronic devices containing small terminals such as input board terminals or mobile phone terminals; medical ventilation applications, etc.

[1031] Liquid filtration field

[1032] Semiconductor liquid filters (for semiconductor manufacturing), hydrophilic PTFE filters (for semiconductor manufacturing), filters suitable for chemicals (for reagent processing), filters for pure water production lines (for pure water production), backwashing type liquid filters (for industrial wastewater treatment), etc.

[1033] General consumables sector

[1034] Clothing, cable conduits (removable cables suitable for motorcycles), motorcycle clothing, cast padding (medical protective gear), vacuum cleaner filters, bagpipes (musical instruments), cables (signal cables for guitars, etc.), strings (for stringed instruments), etc.

[1035] Fiber field

[1036] PTFE fiber (fiber material), sewing thread (fabric), knitting thread (fabric), rope, etc.

[1037] medical field

[1038] Intraocular implants (stretching materials), artificial blood vessels, catheters, general surgery (tissue enhancement materials), head and neck products (dura mater substitutes), intraoral health (tissue regeneration medicine), and plastic surgery (bandages), etc.

[1039] Example

[1040] The present invention will then be described with reference to the embodiments described herein, but the present invention is not limited to the embodiments described herein.

[1041] The values ​​in the examples were measured using the following methods.

[1042] Average primary particle size

[1043] The aqueous dispersion of the fluoropolymer was diluted with water to a solids concentration of 0.15% by mass. The transmittance of the diluted emulsion at 550 nm relative to a unit length was measured, and the average first-order particle size, determined by the orientation diameter measured from transmission electron microscopy images, was used to create a calibration curve. Using this calibration curve, the average first-order particle size was determined from the measured transmittance of the 550 nm transmitted light for each sample.

[1044] Standard Specific Gravity (SSG)

[1045] The determination was performed using samples molded according to ASTM D4895-89 by the water displacement method according to ASTM D-792.

[1046] Melting point (peak temperature)

[1047] For the PTFE powder obtained through the examples, a melting heat curve was plotted using a differential scanning calorimeter (DSC) at a heating rate of 10°C / min. The temperature corresponding to the maximum value of the endothermic peak appearing in the melting heat curve was taken as the melting point of PTFE.

[1048] In addition, for the melt-processable fluoropolymer (PFA, FEP) powder obtained by the examples, the temperature was raised to above the melting point using a differential scanning calorimeter [DSC] at a heating rate of 10°C / min, then cooled to below the melting point at a cooling rate of 10°C / min, and then raised to above the melting point again at a heating rate of 10°C / min. The temperature corresponding to the maximum value of the endothermic peak in the above melt-processable fluoropolymer (PFA, FEP) was taken as the melting point of the melt-processable fluoropolymer (PFA, FEP).

[1049] Content of modified monomers

[1050] The HFP content was calculated as follows: A thin film disk was made by molding PTFE powder. The infrared absorbance of the thin film disk was measured by FT-IR, and the value was calculated at 982 cm⁻¹. -1absorbance at 935cm -1 The ratio of absorbance at each location is multiplied by 0.3 to obtain the result.

[1051] Using the following formula, from solid state 19 The PMVE content was determined by the spectrum obtained from F-MAS NMR measurement (rotation speed 30 kHz).

[1052] X = (4B / 3) / (A + (B / 3)) × 100

[1053] X: PMVE content (mol%)

[1054] A: The integral value of a signal of -120ppm

[1055] B: Integral value of the CF signal at -52ppm

[1056] The chemical shift value is the value when the peak of the signal from the PTFE backbone is set to -120 ppm.

[1057] The CH2=CF(CF2OCFCF3COONH4) (hereinafter also referred to as "modified monomer a") content is the total amount of modified monomer a added.

[1058] Fluoropolymer solid component concentration

[1059] 1 g of the aqueous dispersion of fluoropolymer was dried in a blower dryer at 150 °C for 60 minutes. The mass of the heating residue relative to the mass of the aqueous dispersion (1 g) was expressed as a percentage.

[1060] Content of polymer (1)

[1061] The content of polymers A to D in PTFE powder

[1062] Using the following formula, from solid state 19 The content of polymers A to D in PTFE powder was determined by F-MAS NMR spectroscopy (30 kHz rotation speed).

[1063] Y = (4B / (5A+3B)) × 100

[1064] Y: Content of polymers A through D (mol%)

[1065] A: The integral value of a signal of -120ppm

[1066] B: The sum of the integral values ​​of the CF2 and CF3 signals at -83ppm

[1067] The chemical shift value is the value when the peak of the signal from the PTFE backbone is set to -120 ppm.

[1068] Polymer E content

[1069] Using the following formula, from solid state 19 The content of polymer E in PTFE powder was determined by F-MAS NMR spectroscopy (30 kHz rotation speed).

[1070] Y = (4B / (10A+3B)) × 100

[1071] Y: Content of polymer E (mol%)

[1072] A: The integral value of a signal of -120ppm

[1073] B: The sum of the integral values ​​of the CF2 and CF3 signals at -81 and -83 ppm respectively.

[1074] The chemical shift value is the value when the peak of the signal from the PTFE backbone is set to -120 ppm.

[1075] content of polymer F

[1076] Using the following formula, from solid state 19 The content of polymer F in PTFE powder was determined by the spectrum obtained by F-MAS NMR determination (rotation speed 30 kHz).

[1077] Y = (4B / (4.62A+2.77B)) × 100

[1078] Y: Content of polymer F (mol%)

[1079] A: The integral value of a signal of -120ppm

[1080] B: The sum of the integral values ​​of the CF2 and CF3 signals at -83ppm

[1081] The chemical shift value is the value when the peak of the signal from the PTFE backbone is set to -120 ppm.

[1082] Measurement of extrusion pressure

[1083] Add 21.7g of lubricant (trade name: Isopar H (registered trademark), manufactured by Exxon) to 100g of micronized powder and mix for 3 minutes at room temperature in a glass bottle. Next, before extrusion, leave the glass bottle at room temperature (25°C) for at least 1 hour to obtain lubricating resin. Extrude the lubricating resin through an orifice (2.5mm diameter, 11mm blade length, 30° inlet angle) at room temperature with a reduction ratio of 100:1 to obtain uniform beads (beadings). The extrusion speed, i.e., the punching speed, is set to 20 inches / minute (51cm / minute). The extrusion pressure is obtained by dividing the load at which the extrusion load reaches equilibrium during paste extrusion by the cross-sectional area of ​​the barrel used in the paste extrusion.

[1084] Tensile test

[1085] The beads obtained by extruding the above-described paste are heated at 230°C for 30 minutes to remove the lubricant from the beads. Next, the beads (extruded bodies) are cut to appropriate lengths, and the ends are secured to the chucks with a chuck spacing of 1.5 inches (38 mm). The chucks are then heated to 300°C in an air-circulating oven. Next, the chucks are separated at a desired speed (elongation rate) to a separation distance commensurate with the desired elongation (total elongation), and an elongation test is performed. This elongation method is essentially the same as that disclosed in U.S. Patent No. 4,576,869, except for the extrusion speed (51 cm / min instead of 84 cm / min). "Elongation" refers to the increase in length caused by stretching, and is generally expressed in relation to the original length. In the above manufacturing method, the elongation rate is 1000% / second, and the total elongation is 2400%.

[1086] Fracture strength

[1087] For the tensile beads obtained in the above tensile test (made by elongating beads), they are clamped and fixed in the movable jaws of a gauge with a length of 5.0 cm, and a tensile test is performed at 25°C at a speed of 300 mm / min. The strength at break is used as the breaking strength for determination.

[1088] Stress relaxation time

[1089] The two ends of the tensile beads obtained in the above tensile test were connected to a fixing tool to form a taut bead sample with a total length of 8 inches (20 cm). The oven was maintained at 390°C, and the fixing tool was inserted into the oven through a slit located on the side (covered). The stress relaxation time was measured from the moment of insertion into the oven until the bead sample broke.

[1090] Appearance of stretched material

[1091] Visually observe the appearance of the tensile beads (made by elongating beads) obtained in the above tensile test.

[1092] Aspect Ratio

[1093] Scanning electron microscopy (SEM) was used to observe an aqueous dispersion of PTFE diluted to a solid content of approximately 1% by mass. Images of more than 400 randomly selected particles were processed, and the average ratio of their major axis to minor axis was used to determine the particle size distribution.

[1094] melt flow rate

[1095] The measurements were performed according to ASTM D-1238 and D-2116.

[1096] Mooney viscosity (ML1+10(100℃))

[1097] The measurements were performed at 100°C using a Mooney MV2000E viscometer manufactured by ALPHA TECHNOLOGIES, according to JISK 6300.

[1098] The following formula was used in the example:

[1099] CH2=CF(CF2OCFCF3COONH4)

[1100] The homopolymer of the monomer shown (modified monomer a) has a number-average molecular weight of 90,000 and a weight-average molecular weight of 190,000 (hereinafter referred to as polymer A).

[1101] Regarding the number-average molecular weight and weight-average molecular weight mentioned above, the measurements were performed by gel permeation chromatography (GPC) using a GPC HLC-8020 manufactured by Tosoh Corporation and a column manufactured by Shodex Corporation (combining one GPC KF-801, one GPC KF-802, and two GPC KF-806M connected in series). Tetrahydrofuran (THF) was passed through the column as solvent at a flow rate of 1 ml / min. Monodisperse polystyrene was used as a standard to calculate the molecular weight.

[1102] Example 1

[1103] Add 530 g of deionized water, 30 g of paraffin wax, and 0.52 g of polymer A and ammonia to a 1 L glass reactor equipped with a stirrer, adjusting the pH to 9.2. Next, while heating the reactor contents to 70°C, perform suction and simultaneously purge with TFE monomer to remove oxygen from the reactor. Then, stir the contents at 540 rpm. Add TFE monomer to the reactor until the pressure reaches 0.73 MPaG. Inject 2.75 mg of ammonium persulfate (APS) initiator dissolved in 20 g of deionized water into the reactor to bring the pressure to 0.83 MPaG. After the initiator is injected, a pressure drop occurs, indicating the start of polymerization. Add TFE monomer to the reactor to maintain the pressure, continuing polymerization until approximately 140 g of TFE monomer has reacted completely. Then, vent the reactor until the pressure reaches atmospheric pressure, remove the contents from the reactor, and cool. Remove the supernatant paraffin wax from the PTFE aqueous dispersion.

[1104] The obtained PTFE aqueous dispersion had a solid content concentration of 20.8% by mass and an average primary particle size of 258 nm.

[1105] The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content concentration of approximately 10% by mass, and then solidified under high-speed stirring. The solidified wet powder was dried at 150°C for 18 hours. At this point, the PTFE powder had an SSG of 2.180 and a melting point of 343.1°C.

[1106] Example 2

[1107] The 0.52 g of polymer A from Example 1 was replaced with 0.275 g, the 2.75 mg of ammonium persulfate (APS) initiator was replaced with 11 mg, and 2.9 mg of CH2=CF(CF2OCFCF3COONH4) was added. Polymerization was carried out in the same manner as in Example 1. The resulting aqueous PTFE dispersion had a solids content of 20.4% by mass and an average primary particle size of 280 nm.

[1108] Example 3

[1109] The polymer A from Example 1 was increased from 0.52 g to 1.10 g, and polymerization was carried out in the same manner as in Example 1. The resulting aqueous PTFE dispersion had a solids content of 19.3% by mass and an average primary particle size of 336 nm.

[1110] Example 4

[1111] The polymer A in Example 1 is a homopolymer of the monomer shown in CH2=CF(CF2OCFCF3COONH4) (weight average molecular weight of 4.1×10⁻⁶). 4 Number average molecular weight 1.9 × 104 Polymer B was further polymerized until the amount of wet PTFE aggregates adhering to the reactor and stirring blades reached the same level as in Example 1. Otherwise, polymerization was carried out in the same manner as in Example 1. The resulting aqueous PTFE dispersion had a solids concentration of 17.7% by mass and an average primary particle size of 341 nm.

[1112] Example 5

[1113] The polymer B in Example 4 is a homopolymer of the monomer shown in CH2=CF(CF2OCFCF3COONH4) (weight average molecular weight of 2.7×10). 4 Number average molecular weight 1.1 × 10 4 The polymer C was polymerized in the same manner as in Example 4, except that... The resulting aqueous PTFE dispersion had a solids concentration of 15.0% by mass and an average primary particle size of 292 nm.

[1114] Example 6

[1115] The polymer B in Example 4 is a homopolymer of the monomer shown in CH2=CF(CF2OCFCF3COONH4) (weight average molecular weight of 1.9×10). 4 Number average molecular weight 1.2 × 10 4 Polymer D was polymerized in the same manner as in Example 4, except that the polymerization was carried out in the same way. The resulting aqueous PTFE dispersion had a solids concentration of 12.9% by mass and an average primary particle size of 289 nm.

[1116] Example 7

[1117] In Example 1, 0.18 g of HFP was added, and polymerization was carried out in the same manner as in Example 1. The resulting aqueous PTFE dispersion had a solids content of 21.5% by mass and an average primary particle size of 211 nm.

[1118] The polymerization conditions and evaluation results of the obtained PTFE aqueous dispersions in each of Examples 1 to 7 are shown in Table 1 and Table 2, respectively.

[1119] Example 8

[1120] The 0.52 g of polymer A in Example 1 was converted into 0.55 g of a homopolymer of the monomer shown in CH2=CF(CF2OCFCF3CF2OCFCF3COONH4) (weight average molecular weight of 9.7 × 10⁻⁶). 4 Number average molecular weight 3.3 × 10 4Polymer E was added, along with 0.13 g of PMVE, and polymerization was carried out in the same manner as in Example 1. The resulting aqueous PTFE dispersion had a solids concentration of 21.5% by mass and an average primary particle size of 183 nm.

[1121] Example 9

[1122] The polymer E in Example 8 is a copolymer of TFE and the monomers shown in CH2=CF(CF2OCFCF3COONH4) (weight-average molecular weight of 20.0 × 10⁻⁶). 4 Number average molecular weight 5.8 × 10 4 The polymer F, with a content of 92.4 mol% of the total polymeric units CH2=CF(CF2OCFCF3COONH4), was polymerized in the same manner as in Example 8. The resulting aqueous PTFE dispersion had a solids concentration of 19.6% by mass and an average primary particle size of 350 nm.

[1123] The polymerization conditions and evaluation results of the obtained PTFE aqueous dispersions in each of Examples 8 and 9 are shown in Tables 1 and 2, respectively.

[1124] [Table 1]

[1125]

[1126] [Table 2]

[1127]

[1128] Example 10

[1129] 3560 g of deionized water, 104 g of paraffin wax, 5.37 g of polymer A, and 77.3 mg of CH2=CF(CF2OCFCF3COONH4) were added to a 6 L SUS reactor equipped with a stirrer. Ammonia was added to adjust the pH to 9.1. Next, the reactor contents were heated to 70 °C while being evacuated and purged with TFE to remove oxygen, and the contents were stirred. 0.8 g of HFP was added to the reactor, followed by TFE until the pressure reached 0.73 MPaG. 17.9 mg of ammonium persulfate (APS) initiator dissolved in 20 g of deionized water was injected into the reactor to bring the pressure to 0.83 MPaG. After the initiator was injected, a pressure drop occurred, indicating the start of polymerization. TFE was added to the reactor to maintain a constant pressure of 0.78 MPaG. The supply of TFE and stirring were stopped when approximately 180 g of TFE was consumed in the reaction. Then, the gas in the reactor was slowly released until the reactor pressure reached 0.02 MPaG. Afterward, TFE was supplied until the reactor pressure reached 0.78 MPaG, and stirring was restarted to continue the reaction. When approximately 540 g of TFE was consumed in the reaction, 14.3 mg of hydroquinone dissolved in 20 g of deionized water was injected into the reactor, and the reaction continued. When approximately 1250 g of TFE was consumed in the reaction, the supply of TFE was stopped, stirring was stopped, and the reaction was terminated. Afterward, the pressure in the reactor was vented until atmospheric pressure was reached, and the contents were removed from the reactor and cooled. The supernatant paraffin was removed from the PTFE aqueous dispersion. The resulting PTFE aqueous dispersion had a solids concentration of 25.7% by mass and an average primary particle size of 249 nm. The obtained PTFE aqueous dispersion was diluted with deionized water to a solid content concentration of approximately 10% by mass, and then solidified under high-speed stirring. The solidified wet powder was dried at 210°C for 18 hours. Various physical properties of the obtained PTFE powder were measured. The results are shown in Table 3.

[1130] Example 11

[1131] The polymerization was carried out in the same manner as in Example 10, with the concentration of CH2=CF(CF2OCFCF3COONH4) reduced from 77.3 mg to 9.7 mg and the concentration of HFP reduced from 0.8 g to 0.27 g to PMVE. The resulting aqueous PTFE dispersion had a solids content of 24.4% by mass and an average primary particle size of 275 nm.

[1132] Example 12

[1133] The polymerization was carried out in the same manner as in Example 10, except that the 14.3 mg of hydroquinone from Example 10 was not injected into the reactor. The resulting aqueous PTFE dispersion had a solids content of 25.4% by mass and an average primary particle size of 242 nm.

[1134] Example 13

[1135] 1800 g of deionized water, 90 g of paraffin wax, 2.70 g of polymer A, and 38.9 mg of CH2=CF(CF2OCFCF3COONH4) were added to a 3 L SUS reactor equipped with a stirrer. Ammonia was added to adjust the pH to 9.1. Next, the reactor contents were heated to 80 °C while being evacuated and purged with TFE to remove oxygen, and the contents were stirred. 2.3 g of HFP was added to the reactor, followed by TFE until the pressure reached 1.50 MPaG. 9.0 mg of ammonium persulfate (APS) initiator was injected into the reactor. After the initiator was injected, a pressure drop occurred, indicating the start of polymerization. TFE was added to the reactor, maintaining a constant pressure of 1.50 MPaG. TFE supply and stirring were stopped when approximately 90 g of TFE was consumed in the reaction. Next, the gas in the reactor was slowly released until the reactor pressure reached atmospheric pressure, and then maintained under vacuum for 1 minute. Afterwards, TFE was supplied until the reactor pressure reached 2.50 MPaG, and stirring was restarted to continue the reaction. When approximately 180 g of TFE was consumed in the reaction, 14.4 mg of hydroquinone dissolved in 20 g of deionized water was injected into the reactor, and the reaction continued. When approximately 600 g of TFE was consumed in the reaction, the TFE supply was stopped, stirring was stopped, and the reaction was terminated. Then, the reactor pressure was vented until atmospheric pressure was reached, and the contents were removed from the reactor and cooled. The supernatant paraffin was removed from the PTFE aqueous dispersion. The resulting PTFE aqueous dispersion had a solids concentration of 26.9% by mass and an average primary particle size of 196 nm. The resulting PTFE aqueous dispersion was diluted with deionized water to a solids concentration of approximately 10% by mass, and solidified under high-speed stirring. The solidified wet powder was dried at 210°C for 18 hours. Various physical properties of the obtained PTFE powder were measured. The results are shown in Table 3.

[1136] [Table 3]

[1137]

[1138] Example 14

[1139] 3560 g of deionized water, 104 g of paraffin wax, 3.58 g of polymer A, and 51.6 mg of CH2=CF(CF2OCFCF3COONH4) were added to a 6 L SUS reactor equipped with a stirrer. Ammonia was added to adjust the pH to 9.0. Next, the reactor contents were heated to 70 °C while being evacuated and purged with TFE to remove oxygen, and the contents were stirred. 0.8 g of HFP was added to the reactor, followed by TFE until the pressure reached 0.73 MPaG. 17.9 mg of ammonium persulfate (APS) initiator dissolved in 20 g of deionized water was injected into the reactor to bring the pressure to 0.83 MPaG. After the initiator was injected, a pressure drop occurred, indicating the start of polymerization. TFE was added to the reactor to maintain a constant pressure of 0.78 MPaG. The supply of TFE and stirring were stopped when approximately 180 g of TFE was consumed in the reaction. Then, the gas in the reactor was slowly released until the reactor pressure reached 0.02 MPaG. Afterward, TFE was supplied until the reactor pressure reached 0.78 MPaG, and stirring was restarted to continue the reaction. The supply of TFE was stopped when approximately 900 g of TFE was consumed in the reaction, stirring was stopped, and the reaction was terminated. Then, the reactor pressure was vented until atmospheric pressure was reached, and the contents were removed from the reactor and cooled. The paraffin in the supernatant was removed from the PTFE aqueous dispersion. The resulting PTFE aqueous dispersion had a solids concentration of 20.7% by mass and an average primary particle size of 218 nm. The resulting PTFE aqueous dispersion was diluted with deionized water to a solids concentration of approximately 10% by mass, and solidified under high-speed stirring. The solidified wet powder was dried at 210°C for 18 hours. Various properties of the obtained PTFE powder were measured. The results are shown in Table 4.

[1140] Example 15

[1141] The polymerization was carried out in the same manner as in Example 14, with the concentration of CH2=CF(CF2OCFCF3COONH4) reduced from 51.6 mg to 6.4 mg and HFP reduced to PMVE. The resulting aqueous PTFE dispersion had a solids content of 20.4% by mass and an average primary particle size of 227 nm.

[1142] Example 16

[1143] The polymer A from Example 14 was reduced from 3.58 g to 5.37 g, and the CH2=CF(CF2OCFCF3COONH4) from 51.6 mg to 430 mg. The supply of TFE was stopped when the TFE consumed in the reaction reached approximately 1250 g. Otherwise, polymerization was carried out in the same manner as in Example 14. The resulting aqueous PTFE dispersion had a solids content of 26.1% by mass and an average primary particle size of 227 nm.

[1144] Example 17

[1145] The 51.6 mg CH2=CF(CF2OCFCF3COONH4) from Example 14 was reduced to 6.4 mg, and 1.8 mg of polyoxyethylene (10) octylphenyl ether was added. Otherwise, polymerization was carried out in the same manner as in Example 14. The resulting aqueous PTFE dispersion had a solids content of 20.3% by mass and an average primary particle size of 227 nm.

[1146] Example 18

[1147] 1800 g of deionized water, 90 g of paraffin wax, 1.80 g of polymer A, and 25.9 mg of CH2=CF(CF2OCFCF3COONH4) were added to a 3 L SUS reactor equipped with a stirrer. Ammonia was added to adjust the pH to 9.1. Next, the reactor contents were heated to 80 °C while being evacuated and purged with TFE to remove oxygen, and the contents were stirred. 1.26 g of HFP was added to the reactor, followed by the addition of TFE until the pressure reached 1.50 MPaG. 9.0 mg of ammonium persulfate (APS) initiator was injected into the reactor. After the initiator was injected, a pressure drop occurred, indicating the start of polymerization. TFE was added to the reactor, maintaining a constant pressure of 1.50 MPaG. When approximately 510 g of TFE was consumed in the reaction, the TFE supply was stopped, stirring was stopped, and the reaction was terminated. Afterwards, the pressure inside the reactor was increased to atmospheric pressure, and the contents were removed from the reactor and cooled. The supernatant paraffin was removed from the PTFE aqueous dispersion. The resulting PTFE aqueous dispersion had a solids concentration of 23.5% by mass and an average primary particle size of 202 nm. The obtained PTFE aqueous dispersion was diluted with deionized water to a solids concentration of approximately 10% by mass, and then solidified under high-speed stirring. The solidified wet powder was dried at 180°C for 18 hours. The various physical properties of the obtained PTFE powder were measured. The results are shown in Table 4.

[1148] Example 19

[1149] The HFP from Example 14 was not added, and the reaction was not carried out at the point where approximately 180 g of TFE was consumed. Otherwise, polymerization was performed in the same manner as in Example 14. The resulting aqueous PTFE dispersion had a solids concentration of 20.1% by mass and an average primary particle size of 277 nm.

[1150] Example 20

[1151] 3600 g of deionized water, 180 g of paraffin wax, 7.20 g of polymer A, and 104 mg of CH2=CF(CF2OCFCF3COONH4) were added to a 6 L SUS reactor equipped with a stirrer. Ammonia was added to adjust the pH to 9.1. Next, the reactor contents were heated to 85 °C while being evacuated and purged with TFE to remove oxygen, and the contents were stirred. TFE was added until the pressure reached 2.70 MPaG. 56 mg of ammonium persulfate (APS) and 289 mg of succinyl peroxide (DSP) were added as polymerization initiators. The initiators were injected into the reactor. After the initiators were injected, a pressure drop occurred, indicating the start of polymerization. TFE was added to the reactor, maintaining a constant pressure of 2.70 MPaG. When approximately 900 g of TFE was consumed in the reaction, the TFE supply was stopped, stirring was stopped, and the reaction was terminated. Afterwards, the pressure inside the reactor was increased to atmospheric pressure, and the contents were removed from the reactor and cooled. The paraffin in the supernatant was removed from the PTFE aqueous dispersion. The resulting PTFE aqueous dispersion had a solids concentration of 21.0% by mass and an average primary particle size of 197 nm. The resulting PTFE aqueous dispersion was diluted with deionized water to a solids concentration of approximately 10% by mass and solidified under high-speed stirring. The solidified wet powder was then dried at 180°C for 18 hours. The various physical properties of the obtained PTFE powder were measured. The results are shown in Table 4.

[1152] [Table 4]

[1153]

[1154] Example 21

[1155] Add 530g of deionized water, 30g of paraffin wax, and 0.55g of polymer A and ammonia to a 1L glass reactor equipped with a stirrer, adjusting the pH to 9.1. Next, while heating the reactor contents to 70°C, perform suction and simultaneously purge with TFE monomer to remove oxygen from the reactor. Then, stir the contents at 540 rpm. Add 0.02g of ethane gas and 8.8g of PPVE to the reactor, followed by adding TFE monomer until the pressure reaches 0.73 MPaG. Inject 55mg of ammonium persulfate (APS) initiator dissolved in 20g of deionized water into the reactor to bring the pressure to 0.83 MPaG. A pressure drop occurs after the initiator is injected, indicating the start of polymerization. Add TFE monomer to the reactor, maintaining a constant pressure of 0.78 MPaG. Continue polymerization until approximately 140g of TFE monomer has been added and the reaction is complete. Then, exhaust the gas until the pressure inside the reactor reaches atmospheric pressure, remove the contents from the reactor and cool them. Remove the paraffin from the supernatant from the PFA aqueous dispersion.

[1156] The solid content of the obtained PFA aqueous dispersion was 21.1% by mass.

[1157] The obtained PFA aqueous dispersion was diluted with deionized water to a solid content concentration of approximately 10% by mass, and then solidified under high-speed stirring. The solidified wet powder was dried at 150°C for 18 hours. At this point, the PFA powder had a melt flow rate of 64 g / 10 min, a melting point of 314.3°C, and a PPVE modification amount of 1.2 mol%.

[1158] Example 22

[1159] 2980 g of deionized water, 120 g of paraffin wax, 4.5 g of polymer A, and ammonia were added to a 6 L SUS reactor equipped with a stirrer, and the pH was adjusted to 9.1. Next, the reactor contents were heated to 70 °C while being evacuated and purged with TFE to remove oxygen. The contents were then stirred at 280 rpm. 0.27 g of ethane gas and 26.4 g of PPVE were added to the reactor, followed by the addition of TFE monomer until the pressure reached 0.73 MPaG. 150 mg of ammonium persulfate (APS) initiator dissolved in 20 g of deionized water was injected into the reactor to bring the pressure to 0.83 MPaG. A pressure drop was observed after the initiator injection, indicating the start of polymerization. TFE was added to the reactor, maintaining a constant pressure of 0.78 MPaG. After the reaction started, 4.5 g of PPVE was added for every 115 g of TFE consumed. The supply of TFE and stirring were stopped when approximately 820 g of TFE had been consumed in the reaction. Afterward, the pressure inside the reactor was vented until atmospheric pressure was reached, and the contents were removed from the reactor and cooled. The paraffin in the supernatant was removed from the PFA aqueous dispersion. The resulting PFA aqueous dispersion had a solids concentration of 21.5% by mass.

[1160] The obtained PFA aqueous dispersion was diluted with deionized water to a solid content concentration of approximately 10% by mass, and then solidified under high-speed stirring. The solidified wet powder was dried at 150°C for 18 hours. At this point, the PFA powder had a melt flow rate of 12 g / 10 min, a melting point of 312.4°C, and a PPVE modification amount of 1.3 mol%.

[1161] Example 23

[1162] Add 530 g of deionized water, 30 g of paraffin wax, 8.25 g of polymer A, and 55.0 mg of CH2=CF(CF2OCFCF3COONH4) to a 1 L glass reactor equipped with a stirrer. Add ammonia to adjust the pH to 9.1. Next, while heating the reactor contents to 80°C, perform suction and purge with TFE monomer to remove oxygen from the reactor. Then, stir the contents at 540 rpm. Add 0.02 g of ethane gas and 16.8 g of HFP to the reactor, followed by adding TFE monomer until the pressure reaches 0.73 MPaG. Inject 303 mg of ammonium persulfate (APS) initiator dissolved in 20 g of deionized water to bring the reactor pressure to 0.83 MPa...

Claims

1. A method for manufacturing a fluoropolymer, comprising the steps of: polymerizing a fluorinated monomer in an aqueous medium in the presence of a polymer (1) containing a polymerization unit (1) and under conditions where the amount of a fluorinated surfactant other than the polymer (1) is less than 1 ppm relative to the aqueous medium, thereby obtaining a fluoropolymer, wherein the polymerization unit (1) is based on a monomer represented by the following general formula (1), The number average molecular weight of the polymer (1) is 0.3 x 10 4 above and 30.0 x 10 4 Hereinafter, The fluororesin is a partially crystalline fluoropolymer. CX2=CY(-CZ2-O-Rf-A) (1) In the formula, X may be the same or different, and can be -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and can be -H, -F, alkyl, or fluoroalkyl; Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms; A is -COOM, -SO3M, or -OSO3M; M is -H, a metal atom, or -NR. 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or an organic group; wherein, At least one of X, Y, and Z contains a fluorine atom.

2. The manufacturing method as described in claim 1, wherein, In general formula (1), at least one of X is -H.

3. The manufacturing method as described in claim 1 or 2, wherein, In general formula (1), both X are -H.

4. The manufacturing method as described in claim 1 or 2, wherein, In general formula (1), Rf is a fluorinated alkylene group having 1 to 10 carbon atoms or a fluorinated alkylene group having 2 to 12 carbon atoms with an ether bond.

5. The manufacturing method as described in claim 1 or 2, wherein, The polymerization unit (1) is a polymerization unit (1A) based on the monomer shown in the following general formula (1A). CH2=CF(-CF2-O-Rf-A) (1A) In the formula, Rf and A are the same as above.

6. The manufacturing method as described in claim 1 or 2, wherein, The polymerization unit (1) is a polymerization unit (1a) based on the fluoroallyl ether compound represented by the following general formula (1a). CF2=CH-CF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-A (1a) In the formula, each X is the same, representing F or H; n5 represents 0 or an integer from 1 to 10, and A is the same as defined above.

7. The manufacturing method as described in claim 1 or 2, wherein, A is -COOM.

8. The manufacturing method as described in claim 1 or 2, wherein, M can be -H, -Na, -K, -Li, or -NH4.

9. The manufacturing method as described in claim 1 or 2, wherein, The content of polymer (1) of polymer (1) is more than 90 mol% relative to all polymer units.

10. The manufacturing method as described in claim 1 or 2, wherein, The number average molecular weight of the polymer (1) is 1.0 x 10 4 The above.

11. The manufacturing method as described in claim 1 or 2, wherein, The number average molecular weight of the polymer (1) is 3.0 x 10 4 The above.

12. The manufacturing method as described in claim 1 or 2, wherein, The fluoropolymer is polytetrafluoroethylene.

13. The manufacturing method as described in claim 12, wherein, The polytetrafluoroethylene is a modified polytetrafluoroethylene.

14. A method for manufacturing a stretched body, characterized in that, It includes a step of stretching the polytetrafluoroethylene obtained by the manufacturing method of claim 12 or 13.

15. A composition, characterized in that, It contains a fluoropolymer and a polymer (1) comprising a polymerization unit (1), said polymerization unit (1) being based on a monomer represented by the following general formula (1). The amount of the fluorinated surfactant other than the polymer (1) is less than 1 ppm relative to the fluororesin. The number average molecular weight of the polymer (1) is 0.3 x 10 4 above and 30.0 x 10 4 Hereinafter, The fluororesin is a partially crystalline fluoropolymer. CX2=CY(-CZ2-O-Rf-A) (1) In the formula, X may be the same or different, and can be -H or -F; Y may be -H, -F, alkyl, or fluoroalkyl; Z may be the same or different, and can be -H, -F, alkyl, or fluoroalkyl; Rf is a fluoroalkylene group with 1 to 40 carbon atoms or a fluoroalkylene group with ether bonds having 2 to 100 carbon atoms; A is -COOM, -SO3M, or -OSO3M; M is -H, a metal atom, or -NR. 7 4. Imidazolium with or without substituents, pyridinium with or without substituents, or phosphonium with or without substituents, R 7 It is an H or an organic group; wherein at least one of X, Y and Z contains a fluorine atom.

16. The composition of claim 15, wherein, The polymerization unit (1) is a polymerization unit (1A) based on the monomer shown in the following general formula (1A). CH2=CF(-CF2-O-Rf-A) (1A) In the formula, Rf and A are the same as above.

17. The composition of claim 15 or 16, wherein, The content of polymer (1) is more than 0.0001% by mass and less than 20% by mass relative to the fluoropolymer.

18. The composition of claim 15 or 16, wherein, The fluoropolymer is polytetrafluoroethylene.

19. The composition of claim 18, wherein, The polytetrafluoroethylene is a modified polytetrafluoroethylene.

20. The composition of claim 18, which is stretchable.

21. The composition of claim 18, wherein the tensile strength is 10.0 N or more.

22. The composition of claim 15 or 16, wherein it is in the form of a powder.

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