Thermoplastic polymer composition and method for producing same

Abstract

Provided is a thermoplastic polymer composition containing a fluororesin (A), a crosslinked fluororubber (B), and magnesium oxide (C), wherein: the fluororesin (A) is a copolymer containing an ethylene unit and a tetrafluoroethylene unit; the crosslinked fluororubber (B) is obtained by dynamically crosslinking a fluororubber (b) in the presence of the fluororesin (A), the magnesium oxide (C), and a crosslinking agent (D) under the melting condition of the fluororesin (A); the volume-based 10% particle diameter of the magnesium oxide (C) is 1.0 μm or less; and the mass ratio ((A) / (B)) of the fluororesin (A) to the crosslinked fluororubber (B) is 50 / 50 to 95 / 5.

Description

Thermoplastic polymer composition and method for producing same

[0001] The present disclosure relates to thermoplastic polymer compositions and methods for making the same.

[0002] Patent Document 1 describes a thermoplastic polymer composition comprising 10 to 95% by weight of a fluororesin (A) and 90 to 5% by weight of a crosslinked fluororubber (B), in which the fluororesin (A) comprises a fluorine-containing ethylenic polymer (a) having a melting point of 120 to 330°C, and the crosslinked fluororubber (B) is obtained by dynamically crosslinking at least one kind of fluororubber (b-1) or fluorine-containing thermoplastic elastomer (b-2) under melting conditions in the presence of the fluororesin (A) and a crosslinking agent (C).

[0003] WO 2006 / 057331

[0004] An object of the present disclosure is to provide a thermoplastic polymer composition that can be produced with high productivity and has excellent flex resistance.

[0005] According to the present disclosure, there is provided a thermoplastic polymer composition containing a fluororesin (A), a crosslinked fluororubber (B), and magnesium oxide (C), wherein the fluororesin (A) is a copolymer containing ethylene units and tetrafluoroethylene units, and the crosslinked fluororubber (B) is obtained by dynamically crosslinking the fluororubber (b) in the presence of the fluororesin (A), magnesium oxide (C), and a crosslinking agent (D) under melting conditions for the fluororesin (A), and wherein the magnesium oxide (C) has a 10% particle size on a volume basis of 1.0 μm or less, and the mass ratio ((A) / (B)) of the fluororesin (A) to the crosslinked fluororubber (B) is 50 / 50 to 95 / 5.

[0006] According to the present disclosure, it is possible to provide a thermoplastic polymer composition that can be produced with high productivity and has excellent flex resistance.

[0007] Fig. 1 is an image of a cross section of the thermoplastic polymer composition produced in Experimental Example 1. Fig. 2 is an image of a cross section of the thermoplastic polymer composition produced in Comparative Example 4.

[0008] Specific embodiments of the present disclosure will be described in detail below, but the present disclosure is not limited to the following embodiments.

[0009] The thermoplastic polymer composition of the present disclosure contains a fluororesin (A), a crosslinked fluororubber (B), and magnesium oxide (C).

[0010] (Fluororesin (A)) The fluororesin (A) used in the present disclosure is a copolymer containing ethylene units and tetrafluoroethylene (TFE) units. The thermoplastic polymer composition of the present disclosure contains the fluororesin (A) containing ethylene units and TFE units, and therefore has excellent fuel barrier properties and moldability.

[0011] The molar ratio of ethylene units to TFE units (ethylene units / TFE units) in the copolymer is preferably 10 / 90 or more, more preferably 15 / 85 or more, even more preferably 20 / 80 or more, and preferably 80 / 20 or less, more preferably 63 / 37 or less, even more preferably 62 / 38 or less.

[0012] The fluororesin (A) may be a copolymer of ethylene, TFE, and a monomer copolymerizable with ethylene and TFE. Examples of the copolymerizable monomer include those represented by the following formula CH ２ =CX ５ Rf ３ , C.F. ２ = CFRf ３ , C.F. ２ =CFORf ３ , C.H. ２ = C(Rf ３ ) ２ (In the formula, X ５ is H or F, Rf ３ represents a fluoroalkyl group which may contain an ether bond.) Among them, monomers represented by CF ２ = CFRf ３ , C.F. ２ =CFORf ３ and C.H. ２ =CX ５ Rf ３and at least one selected from the group consisting of fluorine-containing vinyl monomers represented by the formula: ２ =CF-ORf ４ (wherein, Rf ４ represents a perfluoroalkyl group having 1 to 5 carbon atoms. ３ is a fluoroalkyl group having 1 to 8 carbon atoms, CH ２ =CX ５ Rf ３ More preferred is at least one selected from the group consisting of fluorine-containing vinyl monomers represented by the following formula: and HFP is even more preferred. Furthermore, the monomer copolymerizable with ethylene and TFE may be an aliphatic unsaturated carboxylic acid such as itaconic acid or itaconic anhydride.

[0013] The content of ethylene units and TFE units in the copolymer is preferably 90 to 100 mol %, more preferably 95 mol % or more, and even more preferably 99.9 mol % or more, based on the total monomer units of the copolymer, since a thermoplastic polymer composition can be produced with higher productivity and a thermoplastic polymer composition having better flex resistance can be obtained.

[0014] The content of the monomer units copolymerizable with ethylene and TFE in the copolymer is preferably 0 to 10 mol %, more preferably 5 mol % or less, and even more preferably 0.1 mol % or less, based on the total monomer units of the copolymer, since a thermoplastic polymer composition can be produced with higher productivity and a thermoplastic polymer composition having better flex resistance can be obtained.

[0015] The fluororesin (A) is also preferably a TFE / ethylene / HFP copolymer containing HFP-based monomer units (HFP units). The TFE / ethylene / HFP copolymer preferably has a TFE / ethylene / HFP molar ratio of 40-65 / 30-60 / 0.5-20, more preferably 40-65 / 30-60 / 0.5-10.

[0016] The content of each monomer unit in the fluororesin (A) can be calculated by an appropriate combination of NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis depending on the type of monomer.

[0017] The melting point of the fluororesin (A) is preferably 160°C or higher, more preferably 170°C or higher, even more preferably 180°C or higher, particularly preferably 190°C or higher, and is preferably lower than 324°C, more preferably 320°C or lower, even more preferably 300°C or lower, particularly preferably 280°C or lower, and most preferably 260°C or lower, because this enables the thermoplastic polymer composition to be produced with higher productivity and gives a thermoplastic polymer composition having even better flex resistance.

[0018] The melt flow rate (MFR) (297°C) of the fluororesin (A) is preferably 0.5 g / 10 min or more, more preferably 2.0 g / 10 min or more, even more preferably 5.0 g / 10 min or more, particularly preferably 8.0 g / 10 min or more, and most preferably 10 g / 10 min or more, and is preferably 100 g / 10 min or less, more preferably 50 g / 10 min or less, even more preferably 40 g / 10 min or less, and particularly preferably 35 g / 10 min or less, because this enables the production of a thermoplastic polymer composition with higher productivity and results in a thermoplastic polymer composition with even better flex resistance. The MFR of the fluororesin (A) is measured at a temperature of 297°C and a load of 5 kg.

[0019] (Crosslinked Fluororubber (B)) The crosslinked fluororubber (B) contained in the thermoplastic polymer composition of the present disclosure is obtained by dynamically crosslinking the fluororubber (b) in the presence of the fluororesin (A), magnesium oxide (C), and crosslinking agent (D) under the melting conditions of the fluororesin (A). The thermoplastic polymer composition of the present disclosure contains the crosslinked fluororubber (B), and therefore has excellent fuel barrier properties and flexibility.

[0020] Dynamic crosslinking refers to dynamically crosslinking the uncrosslinked fluororubber (b) simultaneously with melt-kneading using a Banbury mixer, a pressure kneader, an extruder, etc. Use of an extruder such as a twin-screw extruder for the crosslinking treatment is preferred because it allows applying a high shear force to the kneaded product.

[0021] Crosslinking under melting conditions means crosslinking the uncrosslinked fluororubber (b) at a temperature equal to or higher than the melting point of the fluororesin (A). The crosslinking temperature is preferably equal to or higher than the melting point of the fluororesin (A), more preferably equal to or lower than 330°C, and even more preferably equal to or lower than 320°C. The crosslinking temperature may be equal to or higher than 150°C as long as it is equal to or higher than the melting point of the fluororesin (A), but is preferably equal to or higher than 220°C, and more preferably equal to or higher than 240°C. By setting the crosslinking temperature within the above range, the fluororesin (A) and the crosslinked fluororubber (B) can be sufficiently kneaded, and at the same time, thermal degradation of the uncrosslinked fluororubber (b) can be suppressed.

[0022] The crosslinked fluororubber (B) can be obtained by crosslinking the uncrosslinked fluororubber (b).

[0023] In this disclosure, fluororubber refers to an amorphous fluoropolymer. "Amorphous" means that the magnitude of the melting peak (ΔH) appearing in differential scanning calorimetry (DSC) (heating rate 10°C / min) or differential thermal analysis (DTA) (heating rate 10°C / min) of the fluoropolymer is 4.5 J / g or less. Fluororubber exhibits elastomeric properties through crosslinking. Elastomeric properties refer to the ability of a polymer to be stretched and to retain its original length when the force required to stretch the polymer is no longer applied.

[0024] Examples of the fluororubber (b) include perfluororubber, partially fluorinated rubber, fluorine-containing thermoplastic elastomer, etc. As the fluororubber (b), partially fluorinated rubber is preferred because it allows the thermoplastic polymer composition to be produced with higher productivity and gives a thermoplastic polymer composition having even better flex resistance.

[0025] In the present disclosure, the partially fluorinated rubber is a fluoropolymer that contains fluoromonomer units and has a perfluoromonomer unit content of less than 90 mol% relative to all monomer units, and has a glass transition temperature of 20°C or less and a melting peak (ΔH) magnitude of 4.5 J / g or less.

[0026] In the present disclosure, a perfluoromonomer is a monomer that does not contain a carbon atom-hydrogen atom bond in the molecule. The perfluoromonomer may be a monomer containing carbon atoms and fluorine atoms, or a monomer in which some of the fluorine atoms bonded to carbon atoms have been substituted with chlorine atoms, or may contain nitrogen atoms, oxygen atoms, sulfur atoms, phosphorus atoms, boron atoms, or silicon atoms in addition to carbon atoms. The perfluoromonomer is preferably a monomer in which all hydrogen atoms have been substituted with fluorine atoms. The perfluoromonomer does not include monomers that provide crosslinking sites.

[0027] Examples of the fluororubber (b) include vinylidene fluoride (VdF)-based fluororubbers, tetrafluoroethylene (TFE) / propylene (Pr)-based fluororubbers, tetrafluoroethylene (TFE) / propylene / vinylidene fluoride (VdF)-based fluororubbers, ethylene / hexafluoropropylene (HFP)-based fluororubbers, ethylene / hexafluoropropylene (HFP) / vinylidene fluoride (VdF)-based fluororubbers, ethylene / hexafluoropropylene (HFP) / tetrafluoroethylene (TFE)-based fluororubbers, etc. Among these, the fluororubber (b) is preferably at least one selected from the group consisting of vinylidene fluoride-based fluororubbers and tetrafluoroethylene / propylene-based fluororubbers.

[0028] The vinylidene fluoride-based fluororubber is preferably a copolymer consisting of 45 to 85 mol % of vinylidene fluoride and 55 to 15 mol % of at least one other monomer copolymerizable with vinylidene fluoride, and more preferably a copolymer consisting of 50 to 80 mol % of vinylidene fluoride and 50 to 20 mol % of at least one other monomer copolymerizable with vinylidene fluoride.

[0029] Examples of at least one other monomer copolymerizable with vinylidene fluoride include tetrafluoroethylene [TFE], hexafluoropropylene [HFP], fluoroalkyl vinyl ether, chlorotrifluoroethylene [CTFE], trifluoroethylene, trifluoropropylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutene, hexafluoroisobutene, vinyl fluoride, and a compound represented by the general formula (100): CHX １０１ =CX １０２ Rf １０１ (In the formula, X １０１ and X １０２ is H on one side and F on the other side, and Rf １０１ is a linear or branched fluoroalkyl group having 1 to 12 carbon atoms), a fluoromonomer represented by the general formula (170): CH ２ =CH-(CF ２ ) ｎ -X １７１ (In the formula, X １７１ is H or F, and n is an integer of 3 to 10. Examples of the monomer include fluoromonomers represented by the formula (I), monomers that provide crosslinking sites, and non-fluorinated monomers such as ethylene, propylene, and alkyl vinyl ethers. These can be used alone or in any combination.

[0030] The fluoroalkyl vinyl ether is preferably perfluoro(methyl vinyl ether) or perfluoro(propyl vinyl ether), more preferably perfluoro(methyl vinyl ether), and may be used alone or in any combination.

[0031] The fluoromonomer represented by the general formula (100) is preferably 2,3,3,3-tetrafluoropropylene or 1,3,3,3-tetrafluoropropylene, and more preferably 2,3,3,3-tetrafluoropropylene.

[0032] As the at least one other monomer copolymerizable with vinylidene fluoride, among others, at least one selected from the group consisting of TFE, HFP, fluoroalkyl vinyl ether, CTFE, and a fluoromonomer represented by general formula (100) is preferred, and at least one selected from the group consisting of TFE, HFP, fluoroalkyl vinyl ether, and 2,3,3,3-tetrafluoropropylene is more preferred.

[0033] Specific examples of vinylidene fluoride-based fluororubbers include VdF / HFP-based rubbers, VdF / HFP / TFE-based rubbers, VdF / CTFE-based rubbers, VdF / CTFE / TFE-based rubbers, VdF / fluoromonomer-based rubbers represented by general formula (100), VdF / fluoromonomer-based rubbers represented by general formula (100) / TFE-based rubbers, VdF / perfluoro(methyl vinyl ether) [PMVE]-based rubbers, VdF / PMVE / TFE-based rubbers, and VdF / PMVE / TFE / HFP-based rubbers. Among these, at least one selected from the group consisting of VdF / HFP rubber, VdF / HFP / TFE rubber, and VdF / 2,3,3,3-tetrafluoropropylene rubber is preferred, and at least one selected from the group consisting of VdF / HFP rubber and VdF / HFP / TFE rubber is more preferred.

[0034] The VdF / HFP rubber preferably has a VdF / HFP molar ratio of 45-85 / 55-15, more preferably 50-80 / 50-20, and even more preferably 60-80 / 40-20.

[0035] The VdF / HFP / TFE rubber preferably has a VdF / HFP / TFE molar ratio of 40-80 / 10-35 / 10-35.

[0036] The VdF / 2,3,3,3-tetrafluoropropylene rubber preferably has a VdF / 2,3,3,3-tetrafluoropropylene molar ratio of 45-85 / 55-15, more preferably 50-80 / 50-20, and even more preferably 60-80 / 40-20.

[0037] The tetrafluoroethylene / propylene-based fluororubber is preferably a copolymer consisting of 45 to 70 mol % of tetrafluoroethylene, 55 to 30 mol % of propylene, and 0 to 5 mol % of a fluoromonomer that provides a crosslinking site.

[0038] The content of each monomer unit in the fluororubber (b) can be calculated by appropriately combining NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis depending on the type of monomer.

[0039] The fluororubber (b) is also preferably a copolymer containing a monomer unit derived from a monomer that provides a crosslinking site. Examples of the monomer that provides a crosslinking site include iodine-containing monomers such as perfluoro(6,6-dihydro-6-iodo-3-oxa-1-hexene) and perfluoro(5-iodo-3-oxa-1-pentene) as described in JP-B-5-63482 and JP-A-7-316234, bromine-containing monomers as described in JP-T-4-505341, and cyano group-containing monomers, carboxyl group-containing monomers, and alkoxycarbonyl group-containing monomers as described in JP-T-4-505345 and JP-T-5-500070.

[0040] The fluororubber (b) may be obtained by using a chain transfer agent during polymerization. A bromine compound or an iodine compound may be used as the chain transfer agent. Polymerization methods using a bromine compound or an iodine compound include, for example, emulsion polymerization in an aqueous medium under pressure in the presence of a bromine compound or an iodine compound in a substantially oxygen-free state (iodine transfer polymerization method). Representative examples of the bromine compound or iodine compound to be used include, for example, compounds represented by the general formula: R ２ I ｘ Br ｙ (wherein x and y are each an integer of 0 to 2 and satisfy 1≦x+y≦2; R ２is a saturated or unsaturated fluorohydrocarbon group or chlorofluorohydrocarbon group having 1 to 16 carbon atoms, or a hydrocarbon group having 1 to 3 carbon atoms, which may contain an oxygen atom). By using a bromine compound or an iodine compound, iodine or bromine is introduced into the polymer and functions as a crosslinking point.

[0041] The fluorine content of the fluororubber (b) is preferably 55 to 73% by mass, more preferably 61% by mass or more, even more preferably 63% by mass or more, still more preferably 65% ​​by mass or more, particularly preferably 67% by mass or more, most preferably 69% by mass or more, and more preferably less than 71% by mass. １９ It can be determined by calculation from the composition of the fluororubber measured by F-NMR.

[0042] The Mooney viscosity at 100°C of the fluororubber (b) (ML1+10(100°C)) is preferably 2 or more, more preferably 5 or more, and even more preferably 10 or more, because this allows the thermoplastic polymer composition to be produced with higher productivity and gives a thermoplastic polymer composition having even better flex resistance. Also, it is preferably 200 or less, more preferably 120 or less, and even more preferably 100 or less. The Mooney viscosity is a value measured in accordance with ASTM-D1646-15 and JIS K6300-1:2013.

[0043] (Magnesium oxide (C)) The thermoplastic polymer composition of the present disclosure contains magnesium oxide (C). The magnesium oxide (C) has a 10% particle size on a volume basis of 1.0 μm or less. Because the thermoplastic polymer composition of the present disclosure contains magnesium oxide with such a small particle size, it can be produced with high productivity and has excellent flex resistance.

[0044] As shown in the image in Figure 1 described later, it has been found that by using magnesium oxide (C) having a 10% particle size on a volume basis of 1.0 µm or less, aggregation of magnesium oxide (C) particles can be suppressed when kneading the magnesium oxide (C) with the fluororesin (A) and the fluororubber (b), and therefore the magnesium oxide (C) can be highly dispersed in the composition. As a result, it is presumed that the final thermoplastic polymer composition contains almost no agglomerates that can serve as starting points for crack generation, and thus has improved flex resistance.

[0045] The volume-based 10% particle size of magnesium oxide (C) is 1.0 μm or less, which allows the production of a thermoplastic polymer composition with higher productivity and provides a thermoplastic polymer composition having even better flex resistance. Therefore, the volume-based 10% particle size is preferably 0.8 μm or less, more preferably 0.6 μm or less, even more preferably 0.4 μm or less, and preferably 0.1 μm or more.

[0046] The 50% particle size on a volume basis of the magnesium oxide (C) is preferably 2.0 μm or less, more preferably 1.5 μm or less, even more preferably 1.0 μm or less, and preferably 0.1 μm or more, because this allows the thermoplastic polymer composition to be produced with higher productivity and gives a thermoplastic polymer composition having better flex resistance.

[0047] The 90% particle size on a volume basis of magnesium oxide (C) is preferably 5.0 μm or less, more preferably 2.5 μm or less, even more preferably 1.5 μm or less, and preferably 0.1 μm or more, because this allows the thermoplastic polymer composition to be produced with higher productivity and gives a thermoplastic polymer composition having better flex resistance.

[0048] The 10% particle size of magnesium oxide (C) is the cumulative 10% particle size on a volume basis, and can be measured by a laser diffraction / scattering method. The 50% particle size of magnesium oxide (C) is the cumulative 50% particle size on a volume basis, and can be measured by a laser diffraction / scattering method. The 90% particle size of magnesium oxide (C) is the cumulative 90% particle size on a volume basis, and can be measured by a laser diffraction / scattering method.

[0049] The purity of magnesium oxide (C) is preferably 99.0 mass% or more. When the purity of magnesium oxide (C) is within the above range, the degree of crosslinking of the crosslinked fluororubber (B) is further improved. The purity of magnesium oxide (C) can be measured, for example, by ICP emission spectrometry.

[0050] The content of magnesium oxide (C) is preferably 0.01 to 10 parts by mass, more preferably 1.0 part by mass or more, even more preferably 2.0 parts by mass or more, more preferably 9.0 parts by mass or less, still more preferably 8.0 parts by mass or less, and particularly preferably 7.0 parts by mass or less, relative to 100 parts by mass of the fluororubber (b), because the thermoplastic polymer composition can be produced with higher productivity and a thermoplastic polymer composition having even better flex resistance can be obtained.

[0051] (Crosslinking Agent (D)) In the present disclosure, a crosslinking agent (D) is used when obtaining the crosslinked fluororubber (B). Examples of the crosslinking agent include crosslinking agents that are commonly used in polyol crosslinking, polyamine crosslinking, and peroxide crosslinking. The crosslinking agent is preferably at least one selected from the group consisting of polyhydroxy compounds, polyamine compounds, and peroxides, and more preferably a polyhydroxy compound.

[0052] Examples of polyamine compounds include hexamethylenediamine carbamate, N,N'-dicinnamylidene-1,6-hexamethylenediamine, 4,4'-bis(aminocyclohexyl)methane carbamate, etc. Among these, N,N'-dicinnamylidene-1,6-hexamethylenediamine is preferred.

[0053] The content of the polyamine compound is preferably from 0.05 to 10 parts by mass, more preferably from 0.5 to 5 parts by mass, based on 100 parts by mass of the fluororubber (b).

[0054] As the polyhydroxy compound, a polyhydroxy aromatic compound is preferably used from the viewpoint of excellent heat resistance. The polyhydroxy aromatic compound is not particularly limited, and examples thereof include 2,2-bis(4-hydroxyphenyl)propane (hereinafter referred to as bisphenol A), 2,2-bis(4-hydroxyphenyl)perfluoropropane (hereinafter referred to as bisphenol AF), resorcinol, 1,3-dihydroxybenzene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 4,4'-dihydroxydiphenyl, 4,4'-dihydroxystilbene, 2,6- Examples include dihydroxyanthracene, hydroquinone, catechol, 2,2-bis(4-hydroxyphenyl)butane (hereinafter referred to as bisphenol B), 4,4-bis(4-hydroxyphenyl)valeric acid, 2,2-bis(4-hydroxyphenyl)tetrafluorodichloropropane, 4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl ketone, tri(4-hydroxyphenyl)methane, 3,3',5,5'-tetrachlorobisphenol A, and 3,3',5,5'-tetrabromobisphenol A. Of these, bisphenol AF is preferred.

[0055] The content of the polyhydroxy compound is preferably 0.05 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the fluororubber (b).

[0056] When the crosslinking agent is a polyhydroxy compound, the crosslinked fluororubber (B) is preferably one obtained by dynamically crosslinking the fluororubber (b) under the melting condition of the fluororesin (A) in the presence of a crosslinking accelerator in addition to the fluororesin (A), magnesium oxide (C), and crosslinking agent (D). The crosslinking accelerator promotes the formation of intramolecular double bonds in the dehydrofluorination reaction of the polymer main chain and the addition of the polyhydroxy compound to the formed double bonds.

[0057] Examples of the crosslinking accelerator include onium compounds, and among the onium compounds, at least one selected from the group consisting of ammonium compounds such as quaternary ammonium salts, phosphonium compounds such as quaternary phosphonium salts, oxonium compounds, sulfonium compounds, cyclic amines, and monofunctional amine compounds is preferred, and at least one selected from the group consisting of quaternary ammonium salts and quaternary phosphonium salts is more preferred.

[0058] The quaternary ammonium salt is not particularly limited, and examples thereof include 8-methyl-1,8-diazabicyclo[5.4.0]-7-undecenium chloride, 8-methyl-1,8-diazabicyclo[5.4.0]-7-undecenium iodide, 8-methyl-1,8-diazabicyclo[5.4.0]-7-undecenium hydroxide, 8-methyl-1,8-diazabicyclo[5.4.0]-7-undecenium methyl sulfate, 8-ethyl-1,8-diazabicyclo[5.4.0]-7-undecenium bromide, 8-propyl-1,8-diazabicyclo[5.4.0]-7-undecenium bromide, 8-dodecyl-1,8-diazabicyclo[5.4.0]-7-undecenium chloride ... tetracosyl-1,8-diazabicyclo[5.4.0]-7-undecenium chloride, 8-benzyl-1,8-diazabicyclo[5.4.0]-7-undecenium chloride (hereinafter referred to as DBU-B), 8-benzyl-1,8-diazabicyclo[5.4.0]-7-undecenium hydroxide, 8-phenethyl-1,8-diazabicyclo[5.4.0]-7-undecenium chloride, 8-(3-phenylpropyl)-1,8-diazabicyclo[5.4.0]-7-undecenium chloride, and the like. Among these, DBU-B is preferred because of its excellent crosslinkability and various physical properties.

[0059] The quaternary phosphonium salt is not particularly limited, and examples thereof include tetrabutylphosphonium chloride, benzyltriphenylphosphonium chloride (hereinafter referred to as BTPPC), benzyltrimethylphosphonium chloride, benzyltributylphosphonium chloride, tributylallylphosphonium chloride, tributyl-2-methoxypropylphosphonium chloride, and benzylphenyl(dimethylamino)phosphonium chloride. Of these, benzyltriphenylphosphonium chloride (BTPPC) is preferred because of its excellent crosslinkability and various physical properties.

[0060] The content of the crosslinking accelerator is not particularly limited, but is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 1 part by mass, per 100 parts by mass of the fluororubber (b).

[0061] In another preferred embodiment, a solid solution (containing no chlorine atoms) of bisphenol AF and benzyltriphenylphosphonium is used as the crosslinking agent and crosslinking accelerator. The mass ratio of benzyltriphenylphosphonium to bisphenol AF in the solid solution is preferably 1:2 to 1:4, taking into consideration the dispersibility of the solid solution in the composition.

[0062] The content of the solid solution (for example, a solid solution of benzyltriphenylphosphonium and bisphenol AF in a mass ratio of 1:4) is preferably 0.1 to 2.0 parts by mass per 100 parts by mass of the fluororubber (b), taking into consideration crosslinkability and dispersibility.

[0063] The peroxide is not particularly limited as long as it is a crosslinking agent commonly used in peroxide crosslinking, and generally, a peroxide that easily generates peroxy radicals in the presence of heat or an oxidation-reduction system is preferred. Specific examples include 1,1-bis(t-butylperoxy)-3,5,5-trimethylcyclohexane, 2,5-dimethylhexane-2,5-dihydroperoxide, di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, α,α'-bis(t-butylperoxy)-p-diisopropylbenzene, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, 2,5-dimethyl-2,5-bis(t-butylperoxy)-hexyne-3, benzoyl peroxide, t-butylperoxybenzene, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, and t-butylperoxybenzoate. Among these, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane and 2,5-dimethyl-2,5-bis(t-butylperoxy)-hexyne-3 are preferred.

[0064] The content of the peroxide is preferably 0.05 to 10 parts by mass, more preferably 1.0 to 5 parts by mass, based on 100 parts by mass of the fluororubber (b).

[0065] When the crosslinking agent is a peroxide, the crosslinked fluororubber (B) is preferably one obtained by dynamically crosslinking the fluororubber (b) under the melting conditions of the fluororesin (A) in the presence of a polyfunctional crosslinking aid in addition to the fluororesin (A), magnesium oxide (C), and crosslinking agent (D).

[0066] Examples of polyfunctional crosslinking aids include triallyl cyanurate, trimethallyl isocyanurate, triallyl isocyanurate (TAIC), triacryl formal, triallyl trimellitate, N,N'-m-phenylene bismaleimide, dipropargyl terephthalate, diallyl phthalate, tetraallyl terephthalate amide, triallyl phosphate, bismaleimide, fluorinated triallyl isocyanurate (1,3,5-tris(2,3,3-trifluoro-2-propenyl)-1,3,5-triisocyanurate), and the like. Examples of the polyfunctional crosslinking aid include tri(5-norbornene-2,4,6-trione), tris(diallylamine)-S-triazine, triallyl phosphite, N,N-diallylacrylamide, 1,6-divindodecafluorohexane, hexaallyl phosphoramide, N,N,N',N'-tetraallylphthalamide, N,N,N',N'-tetraallylmalonamide, trivinyl isocyanurate, 2,4,6-trivinylmethyltrisiloxane, tri(5-norbornene-2-methylene)cyanurate, and triallyl phosphite. Among these, triallyl isocyanurate (TAIC) is preferred. When kneading the fluororubber and the polyfunctional crosslinking aid, an inert inorganic powder or the like impregnated with the polyfunctional crosslinking aid may be used.

[0067] The content of the polyfunctional crosslinking aid is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the fluororubber (b).

[0068] (Acid Acceptor (excluding Magnesium Oxide)) The thermoplastic polymer composition of the present disclosure may contain an acid acceptor other than magnesium oxide. Examples of the acid acceptor (excluding magnesium oxide) include magnesium hydroxide, barium hydroxide, magnesium carbonate, barium carbonate, quicklime, slaked lime, calcium hydroxide, calcium carbonate, calcium silicate, calcium stearate, zinc stearate, calcium phthalate, calcium phosphite, tin oxide, and basic tin phosphite.

[0069] The amount of the acid acceptor to be added is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 8 parts by mass, and even more preferably 0.5 to 6 parts by mass, per 100 parts by mass of the fluororubber (b).

[0070] (Thermoplastic polymer composition) The thermoplastic polymer composition of the present disclosure contains a fluororesin (A), a crosslinked fluororubber (B), and magnesium oxide (C).

[0071] The mass ratio ((A) / (B)) of the fluororesin (A) to the crosslinked fluororubber (B) is 50 / 50 to 95 / 5, preferably 55 / 45 or more, more preferably 60 / 40 or more, and preferably 90 / 10 or less, more preferably 85 / 15 or less. By setting the mass ratio of the fluororesin (A) to the crosslinked fluororubber (B) within the above range, the thermoplastic polymer composition can be produced with high productivity, and a thermoplastic polymer composition having excellent flex resistance can be obtained.

[0072] In the thermoplastic polymer composition of the present disclosure, the fluororesin (A) may form a continuous phase and the crosslinked fluororubber (B) may form a dispersed phase, or the fluororesin (A) and the crosslinked fluororubber (B) may form a co-continuous phase structure, but it is preferred that the fluororesin (A) forms a continuous phase and the crosslinked fluororubber (B) forms a dispersed phase. Also, a co-continuous phase structure of the fluororesin (A) and the crosslinked fluororubber (B) may be contained in part of the structure in which the fluororesin (A) forms a continuous phase and the crosslinked fluororubber (B) forms a dispersed phase.

[0073] Even when the uncrosslinked fluororubber (b) initially forms a matrix when dispersed, when the uncrosslinked fluororubber (b) is changed to the crosslinked fluororubber (B) by a crosslinking reaction, the crosslinked fluororubber (B) has a higher melt viscosity than the uncrosslinked fluororubber (b), so the crosslinked fluororubber (B) forms a dispersed phase, or the fluororesin (A) and the crosslinked fluororubber (B) form a co-continuous phase structure.

[0074] The MFR (297°C) of the thermoplastic polymer composition of the present disclosure is preferably 0.5 g / 10 min or more, more preferably 1.0 g / 10 min or more, even more preferably 5.0 g / 10 min or more, particularly preferably 8 g / 10 min or more, and most preferably 10 g / 10 min or more, and is preferably 100 g / 10 min or less, more preferably 50 g / 10 min or less, even more preferably 40 g / 10 min or less, and particularly preferably 30 g / 10 min or less. The MFR of the thermoplastic polymer composition is measured at a temperature of 297°C and a load of 5 kg.

[0075] One feature of the thermoplastic polymer composition of the present disclosure is that it exhibits a high MIT value. In one embodiment, the thermoplastic polymer composition of the present disclosure exhibits an MIT value 1.2 times or more the MIT value of a thermoplastic polymer composition having the same components except that it contains magnesium oxide having a 10% volumetric particle size of 1.99 μm instead of magnesium oxide (C). The MIT value can be measured using the measurement method described in the Examples. When calculating the MIT value multiplier, not only is the composition of the thermoplastic polymer composition the same except for the 10% volumetric particle size of the magnesium oxide, but the preparation method for preparing test specimens from the thermoplastic polymer composition is also the same. For example, when preparing test specimens by molding an arbitrary thermoplastic polymer composition under specified conditions using an extrusion molding method, the test specimens are prepared by molding a thermoplastic polymer composition containing magnesium oxide having a 10% volumetric particle size of 1.99 μm using the same extrusion molding method under the same conditions.

[0076] The shape of the thermoplastic polymer composition of the present disclosure is not particularly limited, and may be in the form of powder, pellets, crumbs, etc., but pellets are preferred because they can be produced with high productivity.

[0077] The thermoplastic polymer composition of the present disclosure also preferably has electrical conductivity to prevent ignition due to accumulation of static charge. From this viewpoint, the thermoplastic polymer composition of the present disclosure preferably contains a conductive material such as carbon black or acetylene black. The amount of the conductive material relative to the thermoplastic polymer composition of the present disclosure is preferably 0.01 to 20% by mass, more preferably 1 to 18% by mass, and even more preferably 5 to 15% by mass.

[0078] Furthermore, other polymers such as polyethylene, polypropylene, polyamide, polyester, and polyurethane; inorganic fillers such as talc, celite, clay, titanium oxide, carbon black, and barium sulfate; pigments, flame retardants, lubricants, light stabilizers, weather stabilizers, antistatic agents, ultraviolet absorbers, antioxidants, release agents, foaming agents, fragrances, oils, and softeners may be added to the thermoplastic polymer composition of the present disclosure, as long as the addition does not affect the intended effects.

[0079] (Production Method) The thermoplastic polymer composition of the present disclosure can be produced by kneading a fluororubber composition containing the fluororesin (A), the fluororubber (b), magnesium oxide (C) and the crosslinking agent (D) at a temperature equal to or higher than the melting point of the fluororesin (A).

[0080] The thermoplastic polymer composition of the present disclosure can be suitably produced by a production method in which a fluororubber composition containing a fluororesin (A), a fluororubber (b), magnesium oxide (C), and a crosslinking agent (D) is kneaded in the cylinder using an extruder equipped with a cylinder and a die at a temperature equal to or higher than the melting point of the fluororesin (A), and the resulting kneaded mixture is extruded through the die to obtain pellets of the thermoplastic polymer composition. The thermoplastic polymer composition of the present disclosure can be produced by such a production method, and as will be described later, the extrusion pressure is unlikely to increase during production by such a production method, so that the composition can be produced with high productivity.

[0081] In the above-mentioned production method, the fluororubber (b) is dynamically crosslinked when the fluororubber composition is kneaded, and a thermoplastic polymer composition containing the fluororesin (A) and the crosslinked fluororubber (B) can be obtained.

[0082] In the above-mentioned production method, the fluororubber (b), the crosslinking agent (D) and the crosslinking accelerator may be kneaded to prepare a fluororubber compound, and then a fluororubber composition containing the compound, the fluororesin (A) and magnesium oxide (C) may be kneaded at a temperature equal to or higher than the melting point of the fluororesin (A), and the resulting kneaded product may be extruded through a die.

[0083] For the kneading, a Banbury mixer, a pressure kneader, an extruder, or the like can be used.

[0084] The manufacturing method of the present disclosure can be characterized by the fact that when the kneaded material is continuously extruded from the die for 60 minutes, the rate of change in pressure calculated by the following formula is 5% or less. Rate of change in pressure (%)=(X ６０ -X ０ ) / X ０ X ０ : Pressure (MPa) applied to the kneaded material in the die at the start of extrusion X ６０ : Pressure (MPa) applied to the kneaded material in the die 60 minutes after the start of extrusion

[0085] The production method of the present disclosure uses magnesium oxide (C) having a particle size within the above range, and therefore the extrusion pressure is unlikely to increase even when the kneaded material is continuously extruded from the die for a long period of time, and therefore the thermoplastic polymer composition (pellets) can be produced with high productivity.

[0086] (Molded Article) The molded article of the present disclosure can be obtained by molding the above-described thermoplastic polymer composition. The shape of the molded article is not particularly limited, and examples thereof include a tube, a hose, a sheet, and a film.

[0087] The molded article can be produced using a general molding method and molding apparatus, etc. As the molding method, any method such as injection molding, extrusion molding, compression molding, blow molding, calendar molding, vacuum molding, etc. can be used.

[0088] The molded article of the present disclosure can also form, for example, a layer of a laminate. Examples of the laminate include a laminate having a layer made of the molded article of the present disclosure and a layer made of another material. Examples of the other material include fluororesin, non-fluororesin, fluororubber, and non-fluororubber.

[0089] Examples of fluororesins include tetrafluoroethylene (TFE) / perfluoro(alkyl vinyl ether) (PAVE) copolymers, tetrafluoroethylene (TFE) / hexafluoropropylene (HFP) copolymers, TFE / ethylene copolymers [ETFE], TFE / ethylene / HFP copolymers, chlorotrifluoroethylene (CTFE) / ethylene copolymers [ECTFE], polyvinylidene fluoride [PVdF], polychlorotrifluoroethylene [PCTFE], CTFE / TFE copolymers, TFE / vinylidene fluoride (VdF) copolymers [VT], polyvinyl fluoride [PVF], TFE / VdF / CTFE copolymers [VTC], and TFE / HFP / VdF copolymers.

[0090] Examples of non-fluorine resins include polyamide resins, polyolefin resins, vinyl chloride resins, polyurethane resins, polyester resins, polyaramid resins, polyimide resins, polyamideimide resins, polyphenylene oxide resins, polyacetal resins, polycarbonate resins, acrylic resins, styrene resins, acrylonitrile / butadiene / styrene resins (ABS), cellulose resins, polyether ether ketone resins (PEEK), polysulfone resins, polyethersulfone resins (PES), polyetherimide resins, ethylene / vinyl alcohol copolymer resins, polyphenylene sulfide resins, polybutylene naphthalate resins, polybutylene terephthalate resins, and polyphthalamide (PPA).

[0091] Examples of fluororubbers include vinylidene fluoride (VdF)-based fluororubbers, tetrafluoroethylene (TFE) / propylene (Pr)-based fluororubbers, tetrafluoroethylene (TFE) / propylene / vinylidene fluoride (VdF)-based fluororubbers, ethylene / hexafluoropropylene (HFP)-based fluororubbers, ethylene / hexafluoropropylene (HFP) / vinylidene fluoride (VdF)-based fluororubbers, and ethylene / hexafluoropropylene (HFP) / tetrafluoroethylene (TFE)-based fluororubbers.

[0092] Examples of non-fluorine-containing rubbers include acrylonitrile-butadiene rubber, hydrogenated acrylonitrile-butadiene rubber, blended rubber of acrylonitrile-butadiene rubber and polyvinyl chloride, blended rubber of acrylonitrile-butadiene rubber and acrylic rubber, chlorinated polyethylene, fluorine-containing rubber, epichlorohydrin rubber, ethylene-propylene rubber, chlorosulfonated polyethylene rubber, acrylic rubber, silicone rubber, butyl rubber, styrene-butadiene rubber, ethylene-vinyl acetate copolymer, α,β-unsaturated nitrile-conjugated diene copolymer rubber, and hydrogenated α,β-unsaturated nitrile-conjugated diene copolymer rubber.

[0093] The thermoplastic polymer composition, molded article, and laminate of the present disclosure have excellent fuel barrier properties and flex resistance, and can therefore be used in a variety of applications.

[0094] For example, the material has suitable properties for use in seals, bellows, diaphragms, hoses, tubes, electrical wires, and the like, such as gaskets and non-contact and contact type packings (self-sealing packings, piston rings, split ring type packings, mechanical seals, oil seals, etc.), which require heat resistance, oil resistance, fuel oil resistance, LLC resistance, and steam resistance, and are used in the engine body, main driving system, valve train system, lubrication and cooling system, fuel system, intake and exhaust system, etc. of an automobile engine, the transmission system of the drive system, the steering system and brake system of the chassis, basic electrical components of electrical equipment, electrical control system components, and electrical equipment components.

[0095] Specifically, it can be used for the applications listed below.

[0096] Gaskets for the engine body, such as cylinder head gaskets, cylinder head cover gaskets, oil pan packings, general gaskets, O-rings, packings, seals such as timing belt cover gaskets, hoses such as control hoses, vibration-proof rubber for engine mounts, sealing materials for high-pressure valves in hydrogen storage systems, etc.

[0097] Shaft seals such as crankshaft seals and camshaft seals for the main moving system.

[0098] Valve stem seals for engine valves, etc.

[0099] Lubrication and cooling system parts include engine oil cooler hoses, oil return hoses, seal gaskets, etc. for engine oil coolers, water hoses around the radiator, and vacuum pump oil hoses for vacuum pumps.

[0100] Fuel system components include fuel hoses, fuel tubes, fuel sealants, and other fuel system components. Examples of fuel hoses or tubes include filler (neck) hoses, fuel supply hoses, fuel return hoses, vapor (evaporative) hoses, and other fuel hoses, as well as in-tank hoses for fuel tanks, fuel pipe tubes, and carburetor control hoses. Examples of fuel sealants include fuel pump oil seals, fuel tank fuel sender seals, filler seals, and tank gaskets, as well as connector O-rings for fuel pipe tubes, injector cushion rings, injector seal rings, injector O-rings, and carburetor flange gaskets. Other fuel system components include fuel pump diaphragms and valves, in-tank fuel pump mounts, pressure regulator diaphragms and check valves for fuel injection systems, carburetor needle valve petals, accelerator pump pistons, and valve seats and diaphragms for composite air control systems (CACs). Among these, the material is suitable for use as a fuel hose or fuel tube, particularly as a filler neck hose or fuel supply hose, and also as a fuel seal, particularly as a fuel sender seal.

[0101] Intake and exhaust system manifold intake manifold packing, exhaust manifold packing, EGR (exhaust gas recirculation) diaphragms, control hoses, emission control hoses, BPT diaphragms, AB valve afterburn prevention valve seats, throttle body packing, turbocharger turbo oil hoses (supply), turbo oil hoses (return), turbo air hoses, intercooler hoses, turbine shaft seals, etc.

[0102] Transmission-related products include bearing seals, oil seals, O-rings, gaskets, torque converter hoses, etc., as well as AT transmission oil hoses, ATF hoses, O-rings, gaskets, etc.

[0103] Steering system, power steering oil hoses, etc.

[0104] Brake system oil seals, O-rings, gaskets, brake oil hoses, master bag air valves, vacuum valves, diaphragms, master cylinder piston cups (rubber cups), caliper seals, boots, etc.

[0105] Basic electrical components include insulators and sheaths for electrical wires (harnesses), and tubes for harness exterior components.

[0106] Coating materials for various sensor wires in electrical control components.

[0107] Electrical parts such as O-rings, packings, and cooler hoses for car air conditioners, and exterior parts such as wiper blades.

[0108] In addition to automobiles, the present invention is also suitable for applications such as oil-resistant, chemical-resistant, heat-resistant, steam-resistant, or weather-resistant packings, O-rings, hoses, other seals, diaphragms, and valves in transportation means such as ships and aircraft; similar packings, O-rings, seals, diaphragms, valves, hoses, rolls, tubes, chemical-resistant coatings, and linings in chemical plants; similar packings, O-rings, hoses, seals, belts, diaphragms, valves, rolls, and tubes in food plant equipment and food equipment (including household goods); similar packings, O-rings, hoses, seals, diaphragms, valves, and tubes in nuclear plant equipment; and similar packings, O-rings, hoses, seals, diaphragms, valves, rolls, tubes, linings, mandrels, electric wires, flexible joints, belts, rubber sheets, weather strips, and roll blades in PPC copiers in general industrial parts.

[0109] Furthermore, in food rubber sealant applications, while conventional rubber sealants have had problems with flavoring and rubber fragments being mixed into food, the use of the molded product of the present disclosure can alleviate these problems and be used favorably. Because of its chemical resistance, low elution, and low flavoring properties, the product can be applied to oil-resistant, chemical-resistant, heat-resistant, steam-resistant, or weather-resistant sealants, lids, belts, rolls, hoses, tubes, films, coatings, linings, joints, containers, and the like in the medical and chemical fields. In general industrial fields, the product can be used favorably for rubber rolls, O-rings, packing, sealing materials, and the like, for the purpose of improving the strength, slipperiness, chemical resistance, and permeability of rubber materials. In particular, the product can be used favorably for packing applications in lithium-ion batteries, as it can simultaneously maintain both chemical resistance and sealing. It can also be used favorably in other applications requiring low-friction sliding properties.

[0110] Among these, the thermoplastic polymer composition, molded article, and laminate of the present disclosure can be suitably used as a hose for transporting fluids such as hydrogen, air conditioner refrigerants, inert gases, fuels, oils, and water.

[0111] The thermoplastic polymer composition, molded article, and laminate of the present disclosure are also suitable for use as a fuel hose or fuel tube, and particularly suitable for use as a filler neck hose or fuel supply hose. That is, the molded article and laminate are preferably a fuel hose or fuel tube, and particularly preferably a filler neck hose or fuel supply hose.

[0112] Although the embodiments have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the claims.

[0113] <1> According to a first aspect of the present disclosure, there is provided a thermoplastic polymer composition containing a fluororesin (A), a crosslinked fluororubber (B), and magnesium oxide (C), wherein the fluororesin (A) is a copolymer containing ethylene units and tetrafluoroethylene units, and the crosslinked fluororubber (B) is obtained by dynamically crosslinking the fluororubber (b) in the presence of the fluororesin (A), the magnesium oxide (C), and a crosslinking agent (D) under melting conditions for the fluororesin (A), wherein the magnesium oxide (C) has a 10% volumetric particle size of 1.0 μm or less, and wherein the mass ratio of the fluororesin (A) to the crosslinked fluororubber (B) ((A) / (B)) is 50 / 50 to 95 / 5. <2> According to a second aspect of the present disclosure, there is provided a thermoplastic polymer composition according to the first aspect, wherein the magnesium oxide (C) has a 50% volumetric particle size of 1.0 μm or less. <3> According to a third aspect of the present disclosure, there is provided a thermoplastic polymer composition according to the first or second aspect, wherein the content of magnesium oxide (C) is 0.01 to 10 parts by mass per 100 parts by mass of the fluororubber (b). <4> According to a fourth aspect of the present disclosure, there is provided a thermoplastic polymer composition according to any of the first to third aspects, wherein the fluororesin (A) has a melting point of 160 to 320°C. <5> According to a fifth aspect of the present disclosure, there is provided a thermoplastic polymer composition according to any of the first to fourth aspects, wherein the fluororubber (b) is a partially fluorinated rubber. <6> According to a sixth aspect of the present disclosure, there is provided a thermoplastic polymer composition according to any of the first to fifth aspects, wherein the fluororubber (b) is at least one selected from the group consisting of vinylidene fluoride / hexafluoropropylene-based fluororubbers, vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene-based fluororubbers, and tetrafluoroethylene / propylene-based fluororubbers. <7> According to a seventh aspect of the present disclosure, there is provided the thermoplastic polymer composition according to any one of the first to sixth aspects, in which the crosslinking agent (D) is at least one selected from the group consisting of polyhydroxy compounds, polyamine compounds, and peroxides.<8> According to an eighth aspect of the present disclosure, there is provided a thermoplastic polymer composition according to any one of the first to seventh aspects, which exhibits an MIT value that is 1.2 times or more the MIT value of a thermoplastic polymer composition having the same components except that it contains magnesium oxide having a volume-based 10% particle size of 1.99 μm instead of magnesium oxide (C). <9> According to a ninth aspect of the present disclosure, the fluororesin (A) is a copolymer having a molar ratio of ethylene units to tetrafluoroethylene units (ethylene units / TFE units) of 10 / 90 to 62 / 38, and a content of ethylene units and tetrafluoroethylene units of 90 to 100 mol% based on all monomer units, the fluororubber (b) is a vinylidene fluoride / hexafluoropropylene-based rubber having a molar ratio of vinylidene fluoride / hexafluoropropylene of 45 to 85 / 55 to 15, or a vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene-based fluororubber having a molar ratio of vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene of 40 to 80 / 10 to 35 / 10 to 35, the magnesium oxide (C) having a 10% particle size on a volume basis of 0.1 to 0.4 μm, The thermoplastic polymer composition according to any one of the first to eighth aspects is provided, wherein the crosslinking agent (D) is a polyhydroxy compound; the mass ratio ((A) / (B)) of the fluororesin (A) to the crosslinked fluororubber (B) is 60 / 40 to 85 / 15; and the melt flow rate (297°C) of the thermoplastic polymer composition is 1.0 to 30 g / 10 min. <10> According to a tenth aspect of the present disclosure, there is provided a thermoplastic polymer composition according to any one of the first to ninth aspects, which is in the form of pellets. <11> According to an eleventh aspect of the present disclosure, there is provided a molded article obtained by molding the thermoplastic polymer composition according to any one of the first to tenth aspects. <12> According to a twelfth aspect of the present disclosure, there is provided a molded article according to the eleventh aspect, which is a tube or a hose.<13> According to a thirteenth aspect of the present disclosure, there is provided a method for producing a thermoplastic polymer composition according to any one of the first to tenth aspects, comprising using an extruder equipped with a cylinder and a die, kneading a fluororubber composition containing a fluororesin (A), a fluororubber (b), magnesium oxide (C) and a crosslinking agent (D) in the cylinder at a temperature equal to or higher than the melting point of the fluororesin (A), and extruding the resulting kneaded mixture through the die to obtain pellets of the thermoplastic polymer composition. <14> According to a fourteenth aspect of the present disclosure, there is provided a production method according to the thirteenth aspect, wherein when extrusion of the kneaded mixture through the die is continued for 60 minutes, a rate of change in pressure calculated by the following formula is 5% or less: Rate of change in pressure (%)=(X. ６０ -X ０ ) / X ０ X ０ : Pressure (MPa) applied to the kneaded material in the die at the start of extrusion X ６０ : Pressure (MPa) applied to the kneaded material in the die 60 minutes after the start of extrusion

[0114] Next, embodiments of the present disclosure will be described with reference to examples, but the present disclosure is not limited to these examples.

[0115] The values ​​in the examples were measured by the following methods.

[0116] Monomer Composition １９ It was measured by F-NMR analysis.

[0117] Melting Point Using a differential scanning calorimeter (DSC), the melting peak was recorded when the temperature was raised at a rate of 10°C / min, and the temperature corresponding to the maximum value was taken as the melting point.

[0118] Melt Flow Rate (MFR) Using a melt indexer (manufactured by Toyo Seiki Seisakusho, Ltd.), the mass (g) of polymer flowing out from a nozzle with a diameter of 2 mm and a length of 8 mm per unit time (10 minutes) under a load of 5 kg at 297°C was measured.

[0119] Mooney Viscosity: Measured in accordance with ASTM D1646-15 and JIS K6300-1:2013 at a measurement temperature of 100°C.

[0120] Magnesium oxide particle size: The 10% particle size (cumulative 10% particle size on a volume basis), 50% particle size (cumulative 50% particle size on a volume basis), and 90% particle size (cumulative 90% particle size on a volume basis) of magnesium oxide were measured using the laser diffraction / scattering method (ultrasonication method). 70 ml of ethanol was added to 0.700 g of magnesium oxide, and ultrasonication was performed for 3 minutes to prepare a sample solution. Methanol was added to the sample supplying device of the laser diffraction particle size analyzer, and the sample solution was added while circulating the methanol within the sample supplying device. Measurements were performed after 1 minute (30 seconds x 2 times), and the average of the two measurements was taken as the particle size.

[0121] The thermoplastic polymer compositions produced in the Examples and Comparative Examples were compression-molded at 260°C and 5 MPa using a hot press to prepare sheet-like test pieces having a thickness of 0.5 mm, from which dumbbell-shaped test pieces having a gauge length of 3.18 mm were punched out. Using the obtained dumbbell-shaped test pieces, a tensile test was carried out at 25°C and a pulling rate of 50 mm / min in accordance with ASTM D638 using an autograph (AGS-J 5kN, manufactured by Shimadzu Corporation) to measure the tensile modulus.

[0122] The thermoplastic polymer compositions produced in the Examples and Comparative Examples were compression molded using a hot press under conditions of 260°C and 5 MPa to prepare sheet-like test pieces with a thickness of 2 mm, from which dumbbell-shaped test pieces with a thickness of 2 mm and a width of 5 mm were punched. Using the obtained dumbbell-shaped test pieces, a tensile test was carried out at 50 mm / min using an autograph (Shimadzu Corporation, AGS-J 5kN) in accordance with JIS-K6301, and the tensile strength at break and tensile elongation at break at 25°C were measured.

[0123] MIT Value Pellets of the thermoplastic polymer compositions produced in Examples 1 and 2 and Comparative Examples 1 to 3 were molded into extruded sheets using a kneading extrusion pelletizer (Model: IMC-9413, manufactured by Imoto Machinery Co., Ltd., Φ14, L / D20) equipped with a 150 mm wide T-die at a die temperature of 250 ° C and 60 rpm. The extruded sheets were cut to prepare test pieces measuring 12.7 mm in width, 90 mm in length, and 0.5 mm in thickness. The longitudinal direction of the test pieces was perpendicular to the extrusion direction. The thermoplastic polymer compositions produced in Example 3 and Comparative Example 4 were compression molded using a hot press at 260 ° C and 5 MPa to prepare test pieces measuring 12.7 mm in width, 90 mm in length, and 0.5 mm in thickness. The test piece was attached to an MIT tester (model number 12176, manufactured by Yasuda Seiki Seisakusho Co., Ltd.), and the test piece was bent under the conditions of a load of 1.5 kg, a bending angle of 135 degrees on both sides, and a bending frequency of 175 times / min, and the number of times until the test piece broke (MIT value) was measured five times. The average value of the five measurements was taken as the MIT value.

[0124] Rate of Change in Pressure A breaker plate with a mesh (80 / 325 / 80) inserted therein was installed between the die and the head of the extruder, and a pressure gauge was installed upstream of the head to measure the pressure of the thermoplastic polymer composition (kneaded product) in the die.

[0125] The pressure change rate was calculated using the following formula: Pressure change rate (%) = (X ｔ -X ０ ) / X ０ X ０ : Pressure (MPa) applied to the kneaded material in the die at the start of extrusion X ｔ : Pressure (MPa) applied to the kneaded material in the die after t minutes have elapsed since the start of extrusion

[0126] In the examples and comparative examples, the following materials were used.

[0127] Magnesium oxide (C1) "Kyowamag (registered trademark) MF-150" (manufactured by Kyowa Chemical Industry Co., Ltd.) MgO content (purity): 99.6 mass% 10% particle size: 0.35 μm 50% particle size: 0.72 μm 90% particle size: 1.36 μm

[0128] Magnesium oxide (C2) "Kyowamag (registered trademark) 150" (manufactured by Kyowa Chemical Industry Co., Ltd.) MgO content (purity): 98.0 mass% 10% particle size: 1.99 μm 50% particle size: 4.46 μm 90% particle size: 11.9 μm

[0129] Magnesium oxide (C3) "Magsarat (registered trademark) ST" (Kyowa Chemical Industry Co., Ltd.) MgO content (purity): 98.0 mass% 10% particle size: 2.03 μm 50% particle size: 4.92 μm 90% particle size: 12.2 μm

[0130] Magnesium oxide (C4) "Starmag PSF-150" (manufactured by Konoshima Chemical Co., Ltd.) MgO content (purity): 99.4 mass% 10% particle size: 0.31 μm 50% particle size: 0.58 μm

[0131] Example 1 100 parts by mass of VdF rubber (VdF / TFE / HFP=50 / 20 / 30 molar ratio, Mooney viscosity at 100°C 87), 0.3 parts by mass of bisphenol AF crosslinking agent (manufactured by Daikin Industries, Ltd.), 1.45 parts by mass of a solid solution of bisphenol AF and a chlorine atom-free crosslinking accelerator (benzyltriphenylphosphonium (BTP)) (BIS-AF-BTP 4:1 salt (bisphenol AF:BTP=4:1 (mass ratio)), manufactured by Central Glass Co., Ltd.), and 4 parts by mass of magnesium oxide (C1) were kneaded using an 8-inch open roll to obtain a VdF rubber full compound.

[0132] 70 parts by mass of ETFE (ethylene / TFE=35 / 65 molar ratio, melting point 220°C, MFR (297°C) 15.0 g / 10 min) and 30 parts by mass of the full compound of the VdF rubber were fed to a twin-screw extruder (manufactured by Technovel Co., Ltd., device name: KZW15TW-60MG-NH(-700), caliber 15 mm, L / D 60) and melt-kneaded under conditions of a cylinder temperature of 280°C and a screw rotation speed of 400 rpm to produce pellets of a thermoplastic polymer composition. Various physical properties were measured using the obtained pellets by the methods described above. The results are shown in Table 1.

[0133] Comparative Example 1 Pellets of a thermoplastic polymer composition were produced in the same manner as in Example 1, except that magnesium oxide (C2) was used instead of magnesium oxide (C1). The results are shown in Table 1.

[0134] Comparative Example 2 Pellets of a thermoplastic polymer composition were produced in the same manner as in Example 1, except that magnesium oxide (C3) was used instead of magnesium oxide (C1). The results are shown in Table 1.

[0135]

[0136] The thermoplastic polymer composition of Comparative Example 1 had the same components as the thermoplastic polymer composition of Example 1, except that it contained magnesium oxide (C2) having a volume-based 10% particle size of 1.99 μm instead of magnesium oxide (C1). As shown in Table 1, the MIT value of the thermoplastic polymer composition of Example 1 was 1.20 times the MIT value of the thermoplastic polymer composition of Comparative Example 1, indicating that the thermoplastic polymer composition had excellent flex resistance.

[0137] Furthermore, as shown in Table 1, in the method for producing a thermoplastic polymer composition of Example 1, the rate of change in pressure when the kneaded material was continuously extruded from the die for 60 minutes was less than 5%, and it was found that the method could be produced with high productivity.

[0138] Example 2 Pellets of a thermoplastic polymer composition were produced in the same manner as in Example 1, except that 80 parts by mass of ETFE (ethylene / TFE=35 / 65 molar ratio, melting point 220°C, MFR (297°C) 28.9 g / 10 min) and 20 parts by mass of a full compound of VdF-based rubber were melt-kneaded at a screw rotation speed of 300 rpm. The results are shown in Table 2.

[0139] Comparative Example 3 Pellets of a thermoplastic polymer composition were produced in the same manner as in Example 2, except that magnesium oxide (C2) was used instead of magnesium oxide (C1). The results are shown in Table 2.

[0140]

[0141] Example 3 A full compound of VdF rubber was obtained in the same manner as in Example 1, except that magnesium oxide (C1) was changed to magnesium oxide (C4).

[0142] 59.9 g of ETFE (ethylene / TFE = 35 / 65 molar ratio, melting point 220°C, MFR (297°C) 15.0 g / 10 min) was added to a Laboplastomill (manufactured by Toyo Seiki Seisakusho, Ltd.) and, after visually confirming that it was sufficiently melted, 25.7 g of the above VdF rubber full compound was added, and the screw rotation speed was increased to 100 rpm. Stirring was continued until the dispersion and reaction had progressed sufficiently and the torque stabilized, producing a thermoplastic polymer composition. The results are shown in Table 3.

[0143] Comparative Example 4 A thermoplastic polymer composition was produced in the same manner as in Example 3, except that magnesium oxide (C4) was changed to magnesium oxide (C2). The results are shown in Table 3.

[0144]

[0145] Experimental Example 1 A bulk thermoplastic polymer composition was produced in the same manner as in Example 3, except that magnesium oxide (C4) was changed to magnesium oxide (C1). The obtained thermoplastic polymer composition was cut with a microtome, and the cut surface was observed using a scanning electron microscope (SEM) (SU-8020 manufactured by Hitachi High-Technologies Corporation, accelerating voltage 5 kV). An image of the cut surface is shown in Figure 1.

[0146] Experimental Example 2 The bulk thermoplastic polymer composition obtained in Comparative Example 4 was cut with a microtome, and the cut surface was observed with a scanning electron microscope (SEM). An image of the cut surface is shown in FIG.

[0147] As shown in the image of Figure 2, agglomerates were observed in the thermoplastic polymer composition (Comparative Example 4) containing magnesium oxide with a 10% volumetric particle size exceeding 1.0 µm. Furthermore, an elemental mapping image of magnesium element (not shown) obtained at the same time revealed that the agglomerates contained magnesium element. Therefore, it is presumed that the agglomerates were formed from magnesium oxide. On the other hand, as shown in the image of Figure 1, no agglomerates were observed in the thermoplastic polymer composition (Experimental Example 1) containing magnesium oxide with a 10% volumetric particle size of 1.0 µm or less, indicating that each component was sufficiently dispersed.

Claims

1. A thermoplastic polymer composition containing a fluororesin (A), a crosslinked fluororubber (B) and magnesium oxide (C), wherein the fluororesin (A) is a copolymer containing ethylene units and tetrafluoroethylene units, and the crosslinked fluororubber (B) is obtained by dynamically crosslinking the fluororubber (b) in the presence of the fluororesin (A), magnesium oxide (C) and a crosslinking agent (D) under melting conditions of the fluororesin (A), wherein the magnesium oxide (C) has a 10% particle size on a volume basis of 1.0 μm or less, and wherein the mass ratio ((A) / (B)) of the fluororesin (A) to the crosslinked fluororubber (B) is 50 / 50 to 95 / 5.

2. The thermoplastic polymer composition according to claim 1, wherein the magnesium oxide (C) has a 50% particle size on a volume basis of 1.0 μm or less.

3. The thermoplastic polymer composition according to claim 1 or 2, wherein the content of magnesium oxide (C) is 0.01 to 10 parts by mass per 100 parts by mass of the fluororubber (b).

4. The thermoplastic polymer composition according to any one of claims 1 to 3, wherein the melting point of the fluororesin (A) is 160 to 320°C.

5. The thermoplastic polymer composition according to any one of claims 1 to 4, wherein the fluororubber (b) is a partially fluorinated rubber.

6. The thermoplastic polymer composition according to any one of claims 1 to 5, wherein the fluororubber (b) is at least one selected from the group consisting of vinylidene fluoride / hexafluoropropylene-based fluororubbers, vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene-based fluororubbers, and tetrafluoroethylene / propylene-based fluororubbers.

7. The thermoplastic polymer composition according to any one of claims 1 to 6, wherein the crosslinking agent (D) is at least one selected from the group consisting of polyhydroxy compounds, polyamine compounds and peroxides.

8. A thermoplastic polymer composition according to any one of claims 1 to 7, which exhibits an MIT value 1.2 times or more the MIT value of a thermoplastic polymer composition having the same components except that magnesium oxide (C) is replaced with magnesium oxide having a 10% volumetric particle size of 1.99 μm.

9. The fluororesin (A) is a copolymer having a molar ratio of ethylene units to tetrafluoroethylene units (ethylene units / TFE units) of 10 / 90-62 / 38, and the content of ethylene units and tetrafluoroethylene units is 90-100 mol% based on the total monomer units; the fluororubber (b) is a vinylidene fluoride / hexafluoropropylene-based rubber having a vinylidene fluoride / hexafluoropropylene molar ratio of 45-85 / 55-15, or a vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene-based fluororubber having a vinylidene fluoride / tetrafluoroethylene / hexafluoropropylene molar ratio of 40-80 / 10-35 / 10-35; the magnesium oxide (C) has a 10% particle size based on volume of 0.1-0.4 μm; the crosslinking agent (D) is a polyhydroxy compound; The thermoplastic polymer composition according to any one of claims 1 to 8, wherein a mass ratio ((A) / (B)) of the fluororesin (A) to the crosslinked fluororubber (B) is 60 / 40 to 85 / 15, and the thermoplastic polymer composition has a melt flow rate (297°C) of 1.0 to 30 g / 10 min.

10. The thermoplastic polymer composition according to any one of claims 1 to 9, which is in the form of pellets.

11. A molded article obtained by molding the thermoplastic polymer composition according to any one of claims 1 to 10.

12. The molded article according to claim 11 which is a tube or a hose.

13. A method for producing a thermoplastic polymer composition according to any one of claims 1 to 10, comprising the steps of: kneading a fluororubber composition containing a fluororesin (A), a fluororubber (b), magnesium oxide (C) and a crosslinking agent (D) in an extruder equipped with a cylinder and a die at a temperature equal to or higher than the melting point of the fluororesin (A), and extruding the resulting kneaded mixture through the die to obtain pellets of the thermoplastic polymer composition.

14. The method according to claim 13, wherein when the kneaded material is continuously extruded from the die for 60 minutes, the rate of change in pressure calculated by the following formula is 5% or less. Rate of change in pressure (%)=(X ６０ -X ０ ) / X ０ X ０ : Pressure (MPa) applied to the kneaded material in the die at the start of extrusion X ６０ : Pressure (MPa) applied to the kneaded material in the die 60 minutes after the start of extrusion

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