Fluoropolymer compositions and articles made therefrom

Abstract

A fluoropolymer composition comprising a fluoropolymer and one or more heat resistant additives selected from the group consisting of acridones, anthranones, diaminoanthraquinones, acridines, substituted acridones, substituted anthranones, substituted diaminoanthraquinones, and substituted acridines, and a cured fluoropolymer composition formed by curing the fluoropolymer composition.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] none Technical Field

[0003] The present invention relates to fluoropolymer compositions comprising a fluoropolymer and one or more heat resistant additives and articles cured from these fluoropolymer compositions. Background Art

[0004] Elastomer compositions containing fluoropolymers have achieved remarkable commercial success due to their ability to be used in harsh environments, particularly during exposure to high temperatures and corrosive chemicals. For example, compositions containing fluoroelastomers are used in hot sections of aircraft engines, seals in oil well drilling equipment, and as sealing elements in industrial equipment operating at high temperatures and in high-temperature, high-pressure, aqueous environments.

[0005] The properties of cured compositions containing fluoropolymers are primarily due to the stability and inertness of the copolymerized fluorinated monomers that constitute the majority of the polymer backbone of these compounds. Such monomers include tetrafluoroethylene and perfluoro(alkyl vinyl) ethers. In order to fully develop the elastomeric properties, fluoroelastomers are typically crosslinked, i.e., vulcanized or cured. To this end, a small percentage of cure site monomers is copolymerized with the fluorinated monomers. During crosslinking, the cure site monomers react with a curing agent to form a crosslinked fluoroelastomer in the form of an article. Various cure site monomers can be used. For example, cure site monomers containing nitrile groups or halogen-containing cure site monomers can be used. Perfluoroelastomers containing cure site monomers can be cured by any curing agent suitable for use with the type of cure site monomer employed.

[0006] While fluoroelastomers perform well in harsh environments, their properties can still be improved. In particular, due to the high heat environments in which cured fluoropolymer compositions are used, there is a continuing need for fluoropolymer compositions with improved heat resistance. Summary of the Invention

[0007] The present invention relates to a fluoropolymer composition comprising a fluoropolymer and one or more heat-resistant additives selected from acridone, anthrone, diaminoanthraquinone, acridine, substituted acridone, substituted anthrone, substituted diaminoanthraquinone and substituted acridine.

[0008] The present invention further relates to a method comprising the steps of curing a composition comprising a fluoropolymer and one or more heat resistant additives selected from the group consisting of acridones, anthrones, diaminoanthraquinones, acridines, substituted acridones, substituted anthrones, substituted diaminoanthraquinones and substituted acridines.

[0009] The present invention further relates to an article formed from a fluoropolymer composition comprising a fluoropolymer and one or more heat resistant additives selected from the group consisting of acridones, anthrones, diaminoanthraquinones, acridines, substituted acridones, substituted anthrones, substituted diaminoanthraquinones, and substituted acridines.

[0010] The compositions of the present invention provide superior heat resistance to previous fluoropolymer compositions and articles formed therefrom that do not contain heat resistant additives selected from the group consisting of acridones, anthrones, diaminoanthraquinones, acridines, substituted acridones, substituted anthrones, substituted diaminoanthraquinones, and substituted acridines. DETAILED DESCRIPTION

[0011] As used herein, the article "a" refers to one as well as more than one and does not necessarily limit its referent noun to the grammatical category of the singular.

[0012] As used herein, the terms "about" and "at or about" when used to modify an amount or value refer to an approximate amount or value that is greater than or less than the exact amount or exact value recited in the claims or described herein. The exact value of the approximate value is determined based on what one skilled in the art would recognize as a suitable approximation to the exact value. As used herein, the term indicates that similar values ​​that are not precisely recited in the claims or described herein may result in equivalent results or effects to those values ​​recited in the claims or described herein, and that one skilled in the art would recognize that such results and effects are acceptably caused by such similar values.

[0013] As used herein, the term "article of manufacture" refers to an unfinished or finished article, thing, object, or element or feature of an unfinished or finished article, thing, or object. As used herein, when the article of manufacture is unfinished, the term "article of manufacture" may refer to any article, thing, object, element, device, etc. having a form, shape, or configuration that can undergo further processing to become a finished article of manufacture. When the article of manufacture is unfinished, the term "preform" may refer to that form, shape, or configuration, any portion of which can undergo further processing to become finished.

[0014] As used herein, when an article is finished, the term "article" refers to an article, thing, object, element, device, etc. that is in a form, shape, or configuration suitable for a particular use / purpose without requiring further processing of the entire entity or a portion thereof. An article may include one or more elements or subassemblies that are partially finished and await further processing or assembly with other elements / subassemblies that together will constitute the finished article. In addition, as used herein, the term "article" may refer to a system or configuration of articles.

[0015] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," or any other variation thereof, refer to a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not limited to only the listed elements but may include additional elements that are not expressly listed or that are inherent to the process. Furthermore, unless expressly stated to the contrary, "or" refers to an inclusive "or" and not to an exclusive "or." For example, a condition A or B is satisfied by any of the following: A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and both A and B are true (or exists).

[0016] As used herein, the terms "comprises," "comprising," "includes," "including," "has," "having," "consisting essentially of," and "consisting of," or any other variations thereof, may refer to a non-exclusive inclusion or an exclusive inclusion. When these terms refer to a more exclusive inclusion, these terms limit the scope of the claim to those recited materials or steps that materially affect the novel elements of the recited invention. When these terms refer to a full exclusive inclusion, these terms exclude any elements, steps, or components not expressly recited in the claim.

[0017] As used herein, terms describing molecules or polymers follow those in the IUPAC Compendium of Chemical Nomenclature version 2.15, September 7, 2009 (International Union of Pure and Applied Chemistry).

[0018] As used herein, the term "unsaturated fluorinated olefin" refers to a linear, branched, or cyclic hydrocarbon structure containing at least one unsaturated double bond and containing at least one fluorine atom.

[0019] As used herein, the term "alkyl" refers to straight-chain, branched-chain, or cyclic hydrocarbon structures and combinations thereof. Alkyl groups do not include aromatic structures. Examples of straight-chain alkyl groups include methyl, ethyl, propyl, butyl, pentyl, and hexyl. Branched-chain alkyl groups include, for example, sec-butyl and tert-butyl, and isopropyl. Examples of cyclic hydrocarbon groups include cyclopropyl, cyclopentyl, cyclohexyl, cyclobutyl, and cyclooctyl.

[0020] As used herein, the term "alkoxy" refers to an alkyl group attached to an oxygen atom via a single bond. The oxygen atom is then attached to a carbon atom. Examples include methoxy, ethoxy, propoxy, isopropoxy, cyclopropyloxy, and cyclohexyloxy.

[0021] As used herein, the term "compound" refers to a composition capable of being cured (i.e., a curable composition) and refers to a mixture of chemical entities comprising at least a fluoroelastomer or fluoropolymer and a curing agent. The mixture of chemical entities has not yet been cured or has not been subjected to processing conditions that would cause the mixture of chemical entities to undergo curing. As used herein, when used to refer to a curable composition, the term can be used interchangeably with the term "composition."

[0022] As used herein, the prefix term "fluoro," when placed as a prefix before the name of a chemical entity, refers to a chemical entity having at least one fluorine atom, as exemplified by the following names: fluoroelastomer, perfluoroelastomer, fluorovinyl, and perfluorovinyl ether. The prefix "fluoro," when placed as a prefix before the name of a chemical entity, explicitly includes "perfluoro" chemical entities. Thus, the prefix "fluoro," when placed before the name of a chemical entity, refers to both "fluoro-" and "perfluoro-" entities.

[0023] As used herein, the term "aromatic" refers to a chemical entity comprising at least one unsaturated ring of atoms that is stabilized by the interactions of the bonds forming the ring. Such chemical entities are exemplified by benzene and naphthalene.

[0024] As used herein, the term "phenyl" refers to a chemical entity having the formula -C6H5 derived from benzene by removing one hydrogen atom. The carbon atom lacking a hydrogen atom is available to form a bond with another chemical entity.

[0025] As used herein, the term "cured" refers to a resultant entity comprising a fluoroelastomer and / or fluoropolymer and that has been exposed to conditions that cause the fluoroelastomer or fluoropolymer molecules to form sufficient cross-links among themselves (i.e., curing conditions) such that the resultant entity assumes a form or shape or configuration or structure that cannot be reprocessed, molded, or extruded into a different form or shape or configuration or structure. That is, once a resultant entity comprising a fluoroelastomer or fluoropolymer has been exposed to curing conditions and thereby cured, the entity cannot be recured to assume a substantially different form or structure.

[0026] As used herein, the term "curing" refers to the processing of a compound (also referred to herein as a curable composition) to produce an entity that exhibits a form or shape or configuration or structure that cannot be reprocessed, molded, or extruded into a different form or shape or configuration or structure. This processing is referred to as a "curing process / processing," which requires the compound to be exposed to certain conditions in order to initiate the curing process, such conditions being referred to as curing conditions. The entity produced by the curing process is a "cured" entity, that is, an article as defined above. To be clear, curing produces a compound that exhibits the form or shape or configuration or structure of an article. Cured articles of the compounds described herein include, but are not limited to, O-rings, seals, and gaskets. The terms "curing" and "cured" also expressly include varying degrees of processing of the compound such that the resulting entity exhibits a form or shape or configuration or structure that cannot be reprocessed, molded, or extruded into a different form or shape or configuration or structure and that the resulting entity as a result of curing may exhibit certain physical properties. In this regard, these compounds may initially be cured to achieve a form, shape, etc. that cannot be reprocessed, which has been referred to herein as "cured." The cured compound may be further subjected to additional curing conditions that provide additional subsequent curing. Such additional curing conditions may be variously referred to herein as "curing" or "post-curing." That is, the terms "curing," "cured," and "cured" refer both to the initial curing process that produces a first cured produced entity and also specifically to any subsequent curing process that produces a subsequently cured produced entity that may or may not have different material or physical properties than those of the first cured produced entity.

[0027] Unless expressly stated otherwise, any ranges set forth herein expressly include their endpoints. Reciting an amount, concentration, or other value or parameter as a range specifically discloses all possible ranges formed by any possible upper range limit and any possible lower range limit, regardless of whether such a pair of upper and lower range limits is expressly disclosed herein. The compounds, methods, and articles described herein are not limited to the specific values ​​disclosed when defining a range in the specification.

[0028] The disclosure herein of any variation of the methods, compounds, and articles described herein with respect to materials, chemical entities, methods, steps, values, and / or ranges, etc., whether or not identified as preferred, is specifically intended to include any possible combination of materials, methods, steps, values, ranges, etc. For the purpose of providing detailed, precise, and sufficient support for the claims, any disclosed combination is a preferred variation of the methods, compounds, and articles described herein.

[0029] In this specification, if there is a naming error or typographical error regarding the chemical name of any chemical species described herein, the chemical structure takes precedence over the chemical name. Furthermore, if there is an error in the chemical structure of any chemical species described herein, the chemical structure of the chemical species that a person skilled in the art would understand to be the intent of the specification shall prevail.

[0030] A fluoropolymer composition comprising:

[0031] a. Fluoropolymers; and

[0032] b. one or more heat-resistant additives selected from acridones, anthrones, diaminoanthraquinones, acridines, substituted acridones, substituted anthrones, substituted diaminoanthraquinones and substituted acridines.

[0033] The fluoropolymer composition comprises a fluoropolymer. The fluoropolymer comprises polymerized units of one or more, alternatively two or more, fluorinated olefins. The fluorinated olefins may be the same or different, alternatively, when two or more fluorinated olefins are copolymerized, the fluorinated olefins are different from each other. Each fluorinated olefin is independently selected from the group consisting of a fluorovinyl ether, an unsaturated fluorinated olefin, an unsaturated olefin, and a mixture of a fluorovinyl ether, an unsaturated fluorinated olefin, and an unsaturated olefin.

[0034] In one embodiment, the fluorinated vinyl olefin contains additional halogen atoms, alternatively chlorine, in addition to fluorine.

[0035] Examples of fluorinated olefins include, but are not limited to, halo(alkyl vinyl) ethers, perfluoroolefins, perfluoro(alkyl vinyl) ethers (PAVE) and perfluoroalkoxyalkyl vinyl ethers (PAAVE), fluoro(methoxyvinyl) ethers (MOVE), fluoro(olefin ethers), halogenated fluoroolefins such as chlorotrifluoroethylene (CTFE), partially fluorinated olefins such as vinyl fluoride (VF), vinylidene fluoride (VF2), trifluoroethylene, tetrafluoropropylene (TFP), pentafluoropropylene (HPFP), olefins wherein less than half or less than a quarter of the hydrogen atoms are replaced by fluorine, olefins according to the formula CX2=CXR wherein each X is independently hydrogen, fluorine or chlorine and R is hydrogen, fluorine or C1-C 12, alternatively C1 to C3 alkyl, provided that all X and R groups are not all fluorinated groups), hydrogen-containing monomers (such as ethylene, propylene, and other non-fluorinated α-olefins (such as C2 to C9 α-olefins)), fluorinated ester ethers (such as fluorinated ester vinyl ethers), methyl perfluoro(5-methyl-4,7-dioxanonane-8-enoate) (EVE), or perfluoro(4-methyl-3,6-dioxaoct-7-ene)sulfonyl fluoride (PSEPVE), perfluoro(3-methoxypropyl vinyl ether) (MV-31), perfluoro and nitrogen-containing cure site monomers. Those skilled in the art will know where to find or how to prepare these fluorinated monomers, and many of these additional monomers are commercially available.

[0036] Examples of halo(alkyl vinyl) ethers include, but are not limited to, 2-(difluoromethoxy)-1,1-difluoroethylene (HHPMVE), 1,1-difluoro-2-(trifluoromethoxy)ethylene, 1,1-difluoro-2-(chlorodifluoromethoxy)ethylene, 1,1-difluoro-2-(bromodifluoromethoxy)ethylene, 1,1-difluoro-2-(1,1,2,2-tetrafluoroethoxy)ethylene, 2-(pentafluoro)ethoxy-1,1-difluoroethylene, 1,1,2,2,3,3-hexafluoro-1-(1,1-difluorovinyloxy)propane, 1-(1,1-difluoroethoxy)ethylene, perfluorooctane, 1-(1,1-difluorovinyloxy)perfluorononane, 1-(1,1-difluorovinyloxy)perfluorodecane, 1-(1,1-difluorovinyloxy)perfluorooct ...

[0037] Halogenated (alkyl vinyl) ethers can be prepared by heating a reaction mixture comprising a metal, a solvent, and a halo(alkyl ethyl) ether according to the formula RCF2OC(H)(X)CF2Y, wherein R is independently H, F, Cl, Br, CF2H, CF3, CF2CF2H, a linear perfluoroalkyl group having 1 to 12 carbon atoms, or a cyclic perfluoroalkyl group having 1 to 12 carbon atoms, and X and Y are independently Cl, Br, I, or F, wherein X and Y are not both F, to form a reaction product mixture comprising a halo(alkyl vinyl) ether, a solvent, unreacted metal, and a metal salt. Other methods known in the art may also be used for halo(alkyl vinyl) ethers.

[0038] Examples of perfluoroolefins include, but are not limited to, tetrafluoroethylene (TFE), hexafluoropropylene (HFP), or any olefin having the formula CF2=CF-R fPerfluoroolefins (where R f is fluorine or a perfluoroalkyl group having 1 to 8, alternatively 1 to 3, carbon atoms).

[0039] Examples of PAAVE monomers include, but are not limited to, monomers according to the formula CF2=CF-ORf (wherein Rf is a linear, branched, or cyclic perfluorinated alkyl group optionally containing an ether linkage) and CF2=CF(OC n F 2n ) p ORf (wherein Rf is a perfluorinated (C1-C8) alkyl group optionally containing an ether linkage, each n is independently 1 to 4, and p is 1 to 6). When there are more than one C n F 2n When the group is C, "n" can be independently selected, alternatively, n is 1 to 12, alternatively 1 to 6. However, in C n F 2n In the group, those skilled in the art will understand that "n" is not independently selected. n F 2n Can be straight chain or branched. In some embodiments, (OC n F 2n ) p By -O-(CF2) 1-4 -[O(CF2) 1-4 ] 0-1 For example, in U.S. Patent Nos. 6,255,536 and 6,294,627(each Worm et al.) describes such perfluorinated ethers. Examples of suitable PAAVE monomers include, but are not limited to, CF2=CFOCF2OCF3, CF2=CFOCF2OCF2CF3, CF2=CFOCF2CF2OCF3, CF2=CFOCF2CF2CF2OCF3, CF2=CFOCF2CF2CF2OCF3 (MV-31), CF2=CFOCF2CF2CF2CF2OCF3, CF2=CFOCF2CF2OCF2CF3, CF2=CFOCF2CF2CF2OCF3, CF2=CFOCF2CF2CF2CF2OCF2CF3, CF2=CFOCF2CF2OCF2OCF3, CF2=CFOCF2CF2OCF2CF2OCF3, CF2=CFOCF2CF2OCF2CF2CF2OCF3 , CF2=CFOCF2CF2OCF2CF2CF2CF2OCF3, CF2=CFOCF2CF2OCF2CF2CF2CF2CF2OCF3, CF2=CFOCF2CF2(OCF2)3OCF3, CF2=CFOCF2 CF2(OCF2)4OCF3, CF2=CFOCF2CF2OCF2OCF2OCF3, CF2=CFOCF2CF2OCF2CF2CF3, CF2=CFOCF2CF2OCF2CF2OCF2CF2CF3, CF2=CFOCF2CF2OCF2CF2OCF2CF2CF3, CF2=CFOCF2CF(CF3)-O-C3F7(PPVE-2), CF2=CF(OCF2CF(CF3))2-O-C3F7(PPVE-3), and CF2=CF(OCF2CF(CF3))3-O-C3F7(PPVE-4). Methods for preparing PAAVE monomers are known in the art. Many PAAVE monomers are commercially available.

[0040] Examples of suitable PAVE monomers include, but are not limited to, perfluoro(methyl vinyl)ether CF2=CFOCF3, perfluoro(ethyl vinyl)ether CF2=CFOCF2CF3, and perfluoro(n-propyl vinyl)ether CF2=CFOCF2CF2CF3. Mixtures of PAVE and PAAVE may also be employed. Methods for preparing PAVE monomers are known in the art. Many PAVE monomers are commercially available.

[0041] Examples of suitable MOVE monomers include, but are not limited to, those defined in US 7,160,967 B2, such as perfluoro-3,5-dioxa-1-heptene (MOVE 1) (CF2=CFOCF2OCF2CF3) and perfluoro-3,5,8-trioxa-1-nonene (CF3OCF2CF2OCF2OCF=CF2) (MOVE 2). One skilled in the art will know how to prepare MOVE monomers. Many MOVE monomers are commercially available.

[0042] Examples of fluoro(olefin ether) monomers include, but are not limited to, U.S. Pat. Nos. 5,891,965 (Worm et al.) and 6,255, 535 (Schulz et al.). Such monomers include those of the formula CF2=CFCF2(OC n F 2ll ) p Those represented by ORf, wherein n, p and Rf are as defined above for PAAVE monomers. Examples of suitable fluoro(olefin ether) monomers include perfluoroalkoxyalkyl allyl ethers such as CF2=CFCF2OCF2CF2OCF3, CF2=CFCF2OCF2CF2CF2OCF3, CF2=CFCF2OCF2OCF3, CF2=CFCF2OCF2OCF3, CF2=CFCF2OCF2OCF2CF3, CF2=CFCF2OCF2OCF2CF3, CF2=CFCF2OCF2CF2CF2OCF3, CF2=CFCF2OCF2CF2CF2OCF2CF3, CF2=CFCF2OCF2CF2CF2CF2OCF2CF3, CF2=CFCF2OCF2CF2OCF2OCF3, CF2=CFCF2OCF2CF2OCF2CF 2OCF3, CF2=CFCF2OCF2CF2OCF2CF2CF2OCF3, CF2=CFCF2OCF2CF2OCF2CF2CF2CF2OCF3, CF2=CFCF2OCF2CF2OCF2CF2CF2CF2CF2OC F3, CF2=CFCF2OCF2CF2(OCF2)3OCF3, CF2=CFCF2OCF2CF2(OCF2)4OCF3, CF2=CFCF2OCF2CF2OCF2OCF2OCF3, CF2=CFCF2OCF2CF2OCF2CF2CF3, CF2=CFCF2OCF2CF2OCF2CF2CF3, CF2=CFCF2OCF2CF2OCF2CF2OCF2CF2CF3, CF2=CFCF20CF2CF2CF(CF3)-0-C3F7, and CF2=CFCF2(0CF2CF(CF3))2-0-C3F7. Many of these perfluoroalkoxyalkyl allyl ethers can be prepared, for example, according to U.S. Pat. No. 4,349,650(Krespan). In addition, perfluoropropyl allyl ether (CF2=CF-CF2-OC3F7) and perfluoromethoxyethyl allyl ether (CF2=CF-CF2-OC2F40CF3) can be prepared according to the method described in U.S. Patent No. 5,891,965 (Worm). Perfluoroalkoxyalkyl allyl ethers can also be prepared by combining a first component comprising at least one of CF2=CF-CF2-OSO2Cl or CF2=CF-CF2-OSO2CF3, a polyfluorinated compound comprising at least one ketone or carboxylic acid halide or a combination thereof and fluoride ion. The polyfluorinated compound comprising at least one ketone or carboxylic acid halide or a combination thereof and fluoride ion can be, for example, any of those described in U.S. Patent No. 4,349,650 (Krespan). Many fluoro(olefin ether) monomers, such as perfluoroalkoxyalkyl allyl ether monomers, are commercially available.

[0043] In one embodiment, the fluorinated polymer further comprises one or more cure site monomers as polymerized units. The cure sites in the fluoropolymer enable the fluoropolymer to cure to form a cured fluoropolymer (including a fluoroelastomer). In one embodiment, the cure site monomer is selected from the group consisting of: nitrile-containing fluorinated olefins and nitrile-containing fluorinated vinyl ethers. Examples of cure sites in the cure site monomers include, but are not limited to, free radical polymerizable nitriles, imidates, amidines, amides, imides, and amine oxides. Mixtures of any of these cure site monomers can be used in the fluoropolymer compositions according to the present disclosure. Useful nitrile-containing fluorinated olefins and fluorinated vinyl ethers include, but are not limited to, CF2=CFO(CF2) L CN, CF2 = CFO (CF2) u OCF(CF3)CN, CF2=CFO[CF2CF(CF3)O] q (CF2O) y CF(CF3)CN, CF2=CFO[CF2FCF3O] n CF2-CFCF3CN or CF2=CF[OCF2CF(CF3)] r O(CF2) t CN, wherein L is in the range of 2 to 12; u is in the range of 2 to 6; q is in the range of 0 to 4; y is in the range of 0 to 6; n is in the range of 0 to 4; r is in the range of 1 to 2; and t is in the range of 1 to 4. Examples of such nitrile-containing cure site monomers include, but are not limited to, CF2=CFO(CF2)3OCF(CF3)CN, perfluoro(8-cyano-5-methyl-3,6-dioxa-1-octene) (8-CNVE), and CF2=CFO(CF2)5CN.

[0044] It is also possible to use selected chain transfer agents (such as I(CF2) d CN, wherein d is 1 to 10 or 1 to 6) or by perfluorosulfinates (such as NC(CF2) d SO2G, wherein G represents a hydrogen atom or a cation with a valence of 1 or 2) to incorporate nitrile-containing cure sites into the curable fluoropolymer.

[0045] The nitrile-containing monomer, chain transfer agent, and / or initiator typically comprise from about 0.1 to 5 mole percent (in some embodiments, 0.3 to 2 mole percent) of the polymerization components.

[0046] Fluoropolymer provided herein can further or alternatively comprise at least one halogen atom curing site that can participate in for example peroxide curing reaction.The halogen that can participate in for example peroxide curing reaction can be bromine or iodine, alternatively iodine.The halogen atom that can participate in peroxide curing reaction can be located at the end or internal position of main chain, alternatively be located at the terminal position of main chain. However, when the position of the halogen atom that can participate in peroxide curing reaction is located at the terminal position, other reactive curing site can also be present.The amount of iodine, bromine or its combination contained in the fluoropolymer is between 0.001% and 5%, preferably between 0.01% and 2.5% or be 0.1% to 1% or 0.2% to 0.6% by weight relative to the gross weight of fluoropolymer.

[0047] In one embodiment, halogen cure sites are incorporated into the perfluoropolymer by incorporating a monomer containing one or more bromine atoms and / or one or more iodine atoms or a mixture of monomers containing bromine atoms and / or iodine atoms and / or nitrile-containing groups.

[0048] Such fluorinated monomers comprising one or more bromine atoms and / or one or more iodine atoms are according to formula (I) or (II):

[0049] CR 2 R 2 ═(CR 3 R 4 ) n —C R 5R 6 (I)

[0050] Where n = 1-4; R 1 、R 2 、R 3 、R 4 and R 5 is H or F, where R 1 to R 5 At least one of is F; and R 6 is Br or I, preferably I; or

[0051] CF2═CF-O(CR 7 R 8 ) n -R 9 (II)

[0052] Where n = 1-4; R 7 and R 8 is H or F, where R 7 or R 8 At least one of is F; and R 9 is Br or I, alternatively is I.

[0053] Examples of cure site monomers that are capable of participating in a peroxide cure reaction when incorporated into a fluoropolymer include, but are not limited to, CF2═CHBr, CH2═CHCH2Br, CF2═CFCF2Br, CH2═CHCF2CF2Br, CF2═CHI, CH2═CHCH2I, CF2═CFCF2I, CH2═CHCF2CF2I, CF2═CFOC4F8I(MV4I), CF2═CFOC2F4I, CF2═CFOCF2CF(CF3)OC2F4I, CH2═CHCF2CF2I, CF2═CFOCF2CF2CH2I, CF2═CFOCF2CF2CH2CH2I, CF2═CFOC4F8CH2CH2I, and combinations thereof.

[0054] Perfluoroelastomers comprising cure sites can also be obtained by polymerization processes using chain transfer compounds and / or comprising bromine or iodine compounds as chain transfer agents.

[0055] Typical examples of the bromine compound or iodine chain transfer compound used include compounds represented by formula (III):

[0056] R 10 I x Br y (III)

[0057] wherein x and y are each an integer from 0 to 2 and satisfy 1≤x+y≤2; and R10 is a saturated or unsaturated fluorinated hydrocarbon group or chlorofluorocarbon group having 1 to 16 carbon atoms, or a hydrocarbon group having 1 to 3 carbon atoms that optionally includes an oxygen atom. By using a bromine compound or an iodine compound, iodine or bromine is introduced into the polymer and can serve as a crosslinking point.

[0058] Examples of bromine or iodine chain transfer agents include, but are not limited to, 1,3-diiodoperfluoropropane, 2-iodoperfluoropropane, 1,3-diiodoperfluoropropane, 1,4-diiodoperfluorobutane, 1,5-diiodoperfluoropentane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1,12-diiodoperfluorododecane, 1,16-diiodoperfluorohexadecane, diiodomethane, 1,2-diiodoethane, 1,3-diiodoperfluoropropane, CF2Br2, BrCF2CF2Br, CF3CFBrCF2 Br, CFClBr2, BrCF2CFClBr, CFBrClCFClBr, BrCF2CF2CF2Br, BrCF2CFBrOCF3, 1-bromo-2-iodoperfluoroethane, 1-bromo-3-iodoperfluoropropane, 1-bromo-4-iodoperfluorobutane, 2-bromo-3-iodoperfluorobutane, 3-bromo-4-iodoperfluorobutene-1,2-bromo-4-iodoperfluorobutene, and the product of the mono-iodine monobromine substituted product, the diiodine monobromine substituted product and (2-iodoethyl)-and (2-bromoethyl)-substituted product of benzene.These compounds can be used alone or can be used in combination with each other.Among these, from the viewpoint of polymerization reactivity, cross-linking reactivity and availability, it is preferred to use 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane and 2-iodoperfluoropropane.

[0059] Liquid monomers used to prepare fluoropolymers may be pre-emulsified with an emulsifier, such as by adding a gaseous fluoroolefin, before polymerization with the other monomers.

[0060] Fluoropolymers can be cured, non-curable, or curable, alternatively the fluoropolymers can be curable, alternatively non-curable, alternatively cured. One skilled in the art will understand what a cured, non-curable, or curable fluoropolymer is and how to prepare non-curable or curable fluoropolymers. In one embodiment, the curable fluoropolymer can be prepared by copolymerizing with a monomer containing a cure site.

[0061] Fluoropolymers can be amorphous or non-amorphous. Examples of amorphous fluoropolymers include, but are not limited to, fluoroelastomer or perfluoroelastomer adhesives prepared from the halogenated (alkyl vinyl) ethers of the present invention, monomers having cure sites, and additional monomers that impart desired properties to the adhesive.

[0062] The fluoropolymer composition comprises one or more heat-resistant additives, wherein the one or more heat-resistant additives are selected from acridone, anthrone, diaminoanthraquinone, acridine, substituted acridone, substituted anthrone, substituted diaminoanthraquinone and substituted acridine; alternatively, the heat-resistant additive is acridone, alternatively anthrone, alternatively diaminoanthraquinone, alternatively acridine. In one embodiment, the heat-resistant additive is diaminoanthraquinone, alternatively 1,5-diaminoanthraquinone.

[0063] In one embodiment, the substituent groups of the substituted acridone, substituted anthrone, substituted diaminoanthraquinone, and substituted acridine may be known substituents and are not limited. Alternatively, the substituents may include, but are not limited to, linear and / or branched alkyl groups, halogenated alkyl groups, alkenyl groups, alkynyl groups, acrylate functional groups, and methacrylate functional groups; halogen, glycidyl, amine, ether, cyanate, isocyanate, ester, carboxylic acid, carboxylate, succinate, anhydride, mercapto, sulfide, sulfate, sulfinyl, sulfonyl, azide, phosphonate, phosphine, masked isocyano, hydroxyl, and organic functional groups comprising any of the above groups.

[0064] The structures of the heat-resistant additives acridone, anthrone, diaminoanthraquinone and acridine are as follows:

[0065]

[0066] Methods for preparing acridone, anthrone, diaminoanthraquinone, acridine and substituted acridone, anthrone, diaminoanthraquinone, acridine are known in the art. Acridone, anthrone, diaminoanthraquinone, acridine and many substituted acridone, anthrone, diaminoanthraquinone, acridine compounds are commercially available.

[0067] The perfluoroelastomers employed in the compounds of the present invention can be crosslinked with any known curing agent for perfluoroelastomers, such as, but not limited to, polyols such as combinations of organic peroxides and multifunctional coagents (U.S. Pat. Nos. 4,214,060; 4,983,680), organotin compounds (U.S. Pat. No. 5,789,489), bis(aminophenols) such as diaminobisphenol AF (U.S. Pat. No. 6,211,319 B1), aromatic tetramines (e.g., 3,3'-diaminobenzidine, 2,2-bis[3-amino-4-(N-phenylamino)phenyl]hexafluoropropane), and ammonia-generating compounds (e.g., urea, urea derivatives such as guanylthiourea), and other compounds disclosed in U.S. Pat. No. 6,281,296 and WO 01 / 27194.

[0068] One curing agent that can be used is an organic peroxide / multifunctional coagent system. Useful organic peroxides are those that generate free radicals at the curing temperature. Dialkyl peroxides or bis(dialkyl peroxides) that decompose at temperatures above 50°C are particularly preferred. In many cases, it is preferred to use di-tert-butyl peroxide having a tertiary carbon atom attached to the peroxy oxygen. Among them, the most useful peroxides of this type are 2,5-dimethyl-2,5-di(tert-butylperoxy)hexyne-3 and 2,5-dimethyl-2,5-di(tert-butylperoxy)-hexane. Other peroxides can be selected from compounds such as dicumyl peroxide, dibenzoyl peroxide, tert-butyl perbenzoate, and di[1,3-dimethyl-3-(tert-butylperoxy)butyl] carbonate. When present in the curable composition of the present invention, 1-5 phr of peroxide is typically used.

[0069] The polyfunctional coagents employed with the organic peroxide are polyunsaturated compounds that can cooperate with the peroxide to provide a useful cure. These coagents can be added in amounts equal to 0.1 and 10 phr, preferably between 2 and 5 phr. The coagents can be one or more of the following compounds: triallyl cyanurate; triallyl isocyanurate; triallyl polyisocyanurate, tris(methallyl)isocyanurate; tris(diallylamine)-s-triazine; triallyl phosphite; N,N-diallylacrylamide; hexaallylphosphoramide; N,N,N',N'-tetraalkyltetraphthalamide; N,N,N',N'-tetraallylmalonamide; trivinyl isocyanurate; 2,4,6-trivinylmethyltrisiloxane; and tris(5-norbornene-2-methylene)cyanurate. Particularly useful is triallyl isocyanurate (TAIC).

[0070] Other curing agents that may be employed in the compounds of the present invention include bis(aminophenols) such as diaminobisphenol AF, tetramines, organotin compounds, and compounds that decompose to generate ammonia at curing temperatures (e.g., urea). When present in the compounds of the present invention, typically 0.1 to 7 phr of any of the later curing agents is employed.

[0071] Additional additives commonly used in curable fluoropolymer compositions may be included in the curable fluoropolymer composition of the present invention. Those skilled in the art will recognize the common additives used, such as fillers; metal sulfides, non-perfluoroelastomers capable of independently crosslinking with any perfluoroelastomer (A) cure site; stabilizers; plasticizers; lubricants; fillers; and processing aids.

[0072] Examples of metal sulfides include, but are not limited to, calcium sulfide, magnesium sulfide, manganese sulfide, iron sulfide, and copper sulfide. The concentration of the metal sulfide is generally about 0.1 to 20 phr, preferably 1 to 20 phr, more preferably 5 to 20 phr.

[0073] Examples of non-perfluoroelastomers are those having at least one crosslinkable group selected from the group consisting of a cyano group (-CN), a carboxyl group (-COOH), an alkoxycarbonyl group (-COOR9, wherein R9 is a monovalent organic group), and an acyl halide group (-COX1, wherein X1 is a halogen atom) capable of undergoing a crosslinking reaction with the perfluoroelastomer (A) at least at the end of its main chain or its side chain.

[0074] Examples of non-perfluoroelastomers include, but are not limited to, rubbers that contain fluorine but are not perfluoroelastomers; thermoplastic fluoroelastomers; and rubber compositions containing fluoroelastomers.

[0075] The fluoroelastomer may contain monomer units independently selected from the group consisting of vinylidene fluoride (VDF), tetrafluoroethylene, and hexafluoropropylene, and at least one additional monomer, such as tetrafluoroethylene, hexafluoropropylene, perfluoro(alkyl vinyl ether), chlorotrifluoroethylene, trifluoroethylene, trifluoropropylene, pentafluoropropylene, trifluorobutylene, tetrafluoroisobutylene, vinyl fluoride, and iodine-containing fluorinated vinyl ethers, ethylene, propylene, alkyl vinyl ethers, and combinations thereof. Those skilled in the art will know how to prepare non-perfluoroelastomers.

[0076] Examples of fillers include, but are not limited to, carbon black and non-carbon black fillers such as anhydrous silica (e.g., acidic silica or fumed silica). Such silica is available from Degussa Aktiengesellschaft (Frankfurt, Germany) and Trademarks available. Particularly useful types are 200 silica. Other suitable silicas include those available from Tokuyama KK (Tokyo, Japan) Silicon dioxide, e.g. QS13,

[0077] QS102 and QS30. The filler amount ranges from 1 to 25 phr, but preferably does not exceed 1 to 7 phr.

[0078] Additional types of fillers include micropowders or fluoroadditives. Micropowders are typically partially crystalline polymers. Micropowders include finely divided, easily dispersible plastic fluoropolymers that are solid at the highest temperatures used in the manufacture and curing of the compounds described herein. The term "solid" refers to plastic fluoropolymers that have a crystalline melting temperature above the processing temperature of the compounds described herein.

[0079] Micropowders that can be used in these compounds include, but are not limited to, micropowders based on the group of polymers known as tetrafluoroethylene (TFE) polymers. This group includes polytetrafluoroethylene (PTFE) and copolymers of TFE with a small concentration of about 1 mole percent or less of at least one copolymerizable modifying monomer so that the micropowder does not melt or soften during processing of the perfluoroelastomer A containing the micropowder. The modifying monomer can be, for example, hexafluoropropylene (HFP), perfluoro(propyl vinyl) ether (PPVE), perfluorobutylethylene, chlorotrifluoroethylene, or another monomer that introduces side groups into the polymer molecule.

[0080] Tetrafluoroethylene polymers used as additives in these compounds include copolymers of TFE having a sufficient concentration of copolymerized units of one or more monomers to lower the melting point below that of PTFE. Such copolymers generally have a carbonyl group with a carbonyl group of 0.5 to 60 × 10 3 Melt viscosities in the Pa·s range are known, but viscosities outside this range are also known. Perfluoroolefins and perfluoro(alkyl vinyl) ethers are preferred comonomers. Hexafluoropropylene and perfluoro(propyl vinyl) ether are most preferred. Examples of TFE copolymers include TFE / hexafluoropropylene copolymers and TFE / perfluoro(propyl vinyl) ether copolymers, provided that they meet the limitations on melt temperature relative to the processing temperature of the perfluoroelastomer. If the particle size is acceptable, these copolymers can be used in the form of a powder separated from the polymerization medium, or they can be ground to a suitable particle size starting from a larger size feedstock.

[0081] The fluoropolymer compositions described herein can be compounds that can be prepared by mixing the perfluoropolymer and heat-resistant additives and any other components of the fluoropolymer composition (e.g., one or more curing agents, fillers) using known rubber compounding procedures (e.g., a two-roll rubber mill, an internal mixer) or in an extruder until homogeneous. These compositions and compounds can be cured by applying heat and / or pressure sufficient to cause, for example, the curing agent to form crosslinks with the curing sites, or a dual-cure system can be used. When compression molding is used for curing, the pressurized curing cycle is preferably followed by a post-cure cycle to achieve the optimal cure state, during which the pressurized cured compound is heated at an elevated temperature exceeding 200° C. for several hours.

[0082] When cured, the compositions described herein become the articles described herein and exhibit thermal stability and chemical resistance suitable for the applications in which they are used. These articles are useful as seals and gaskets for high temperature environments, in a wide range of chemical environments, in seals for high temperature automotive applications, and as O-rings.

[0083] The compounds of the present invention are useful in the production of gaskets, pipes, seals, and other molded parts. Such articles are typically produced by molding a compounded formulation of a fluoropolymer composition with various additives under pressure, curing the part, and then subjecting it to a post-cure cycle. The cured composition has excellent mechanical properties as well as excellent thermal stability and chemical resistance.

[0084] The fluoropolymer compositions of the present invention show improved weight loss and compression set characteristics.

[0085] Examples

[0086] The following examples are given to better illustrate the method of the present invention, but should not be considered to limit the invention described in the appended claims. Unless otherwise stated, all parts and percentages reported in the examples are by weight. The following table describes the abbreviations used in the examples:

[0087] Table 1. List of abbreviations used in the examples. (Not all of these are used in the examples.)

[0088]

[0089]

[0090] FFKM 1: An uncured perfluorinated fluoropolymer prepared with a nitrile cure site monomer and at least one fluoromonomer as described above.

[0091] FFKM 2: Uncured perfluorinated fluoropolymer prepared with iodine cure sites

[0092] FFKM 3: Uncured perfluorinated fluoropolymer prepared with iodine cure sites

[0093] Weight loss: The weight loss was tested by placing the cured O-rings in an air oven at 300°C for six weeks. After each week, a section was removed and the weight was measured and the weight loss was calculated.

[0094] Compounding of the compositions: Curable compositions containing the ingredients shown in Tables 2, 3, and 4 were prepared by compounding the ingredients in a conventional manner using an internal mixer and / or a two-roll rubber mill. The properties of these compositions are also shown in Tables 2, 3, and 4.

[0095] O-rings: O-rings used for weight loss testing were made by molding and curing using conventional methods.

[0096] Curing: Curing was performed according to conventional methods and tested using an MDR to ensure proper curing.

[0097] Compression Set: Compression set was performed according to ASTM D395 under the conditions listed in Tables 3 and 4.

[0098] Table 2. Compound compositions used for curing into O-rings and testing for weight loss.

[0099]

[0100]

[0101] Table 3. Compounding compositions for compression set and weight loss

[0102]

[0103]

[0104] Table 4. Compounding compositions for compression set and weight loss (continued).

[0105]

[0106]

Claims

1. A fluoropolymer composition comprising: a. Fluoropolymers; and b. one or more heat-resistant additives selected from acridones, anthrones, diaminoanthraquinones, acridines, substituted acridones, substituted anthrones, substituted diaminoanthraquinones and substituted acridines.

2. The fluoropolymer composition according to claim 1, further comprising c) a curing agent, and wherein the fluoropolymer is curable and is a copolymer derived from a cure site monomer and at least one fluorine-containing monomer.

3. The fluoropolymer compound according to claim 2, wherein The cure site monomer is a nitrile cure site monomer.Guanilothiourea is added as a dependent claim.

4. The fluoropolymer compound according to claim 3, wherein The cure site monomer is perfluoro(8-cyano-5-methyl-3,6-dioxaoct-1-ene), CF2=CF-O(CF2) n CN (straight chain CNVE), CF2=CF-O[CF2-CFCF 3- O] n -CF2-CFCF3CN, or CF2=CF-[OCF2CFCF3] x -O-(CF2) n CN, CF2=CF-O-(CF2) n -O-CF(CF3)CN.

5. The fluoropolymer composition according to claim 2, wherein The fluorine-containing monomer is one or more monomers selected from the group consisting of tetrafluoroethylene (TFE), vinyl fluoride (VF), perfluoro(alkyl vinyl) ether (PAVE), ethylene, tetrafluoropropylene (TFP), ester vinyl ether, methyl perfluoro(5-methyl-4,7-dioxanonane-8-enoate) (EVE), perfluoro(4-methyl-3,6-dioxaoct-7-ene)sulfonyl fluoride (PSEPVE), vinylidene fluoride (VF2), hexafluoropropylene (HFP), chlorotrifluoroethylene (CTFE), propylene (P), perfluoro-3,5-dioxa-1-heptene (MOVE 1) and perfluoro-3,5,8-trioxa-1-nonene (MOVE2), pentafluoropropylene (HPFP), perfluoro(3-methoxypropyl vinyl) ether (MV-31), 2-(difluoromethoxy)-1,1-difluoroethylene (HHPMVE), and the like.

6. Fluoropolymer composition according to any one of the preceding claims, wherein The substituted acridones, substituted anthrones, substituted diaminoanthraquinones, and substituted acridines are substituted with groups selected from the group consisting of linear alkyl groups, branched alkyl groups, haloalkyl groups, alkenyl groups, alkynyl groups, acrylate functional groups, and methacrylate functional groups; halogens, glycidyl groups, amines, ethers, cyanates, isocyanates, esters, carboxylic acids, carboxylates, succinates, anhydrides, mercaptos, sulfides, sulfates, sulfinyl groups, sulfonyl groups, azides, phosphonates, phosphines, masked isocyanates, and hydroxyl groups.

7. The fluoropolymer composition according to any one of the preceding claims, wherein The diaminoanthraquinone is 1,5-diaminoanthraquinone.

8. Fluoropolymer according to any one of the preceding claims, wherein The curing agent is a compound that generates ammonia.

9. Fluoropolymer according to any one of the preceding claims, wherein The curing agent is 0.1 to 7 phr of the fluoropolymer composition and the heat resistant additive is 1 to 10 phr of the fluoropolymer composition.

10. Fluoropolymer according to any one of the preceding claims, wherein The fluoropolymer composition is amorphous.

11. A cured fluoropolymer composition formed by curing the fluoropolymer composition according to any one of the preceding claims.

12. The cured fluoropolymer composition of claim 11, wherein The cured fluoropolymer composition is an elastomer.

13. The cured fluoropolymer composition according to claim 11 or 12, wherein The cured fluoropolymer composition is in the form of a seal.

14. A method comprising the steps of: Curing the composition according to any one of claims 1 to 10.

15. An article comprising the cured composition according to any one of claims 11 or 12.

16. The article of claim 15, wherein The article is in the form of a gasket, a seal, a tube, a sheet, a washer or an O-ring.

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