JP2013014640A - Fluorine-containing elastomer composition - Google Patents

Abstract

The present invention provides a fluorine-containing elastomer composition capable of obtaining a conveying member having a sufficiently reduced flavoring property.
A fluorine-containing elastomer composition containing a crosslinkable fluorine-containing elastomer, wherein a hydrocarbon-based compound does not substantially leak onto the surface of the crosslinked product.
[Selection figure] None

Description

The present invention relates to a fluorine-containing elastomer composition. More specifically, the present invention relates to a fluorine-containing elastomer composition suitable for a conveying member.

In various manufacturing plants, pipes for transferring chemicals, water, and the like are exposed to various chemicals and high temperatures in manufacturing processes or maintenance processes such as cleaning. For this reason, sealing materials such as gaskets and packings used for piping are required to have excellent chemical resistance and heat resistance. In addition, in manufacturing plants for food, beverage products, cosmetics, etc., odor components such as products and raw materials adhere to the sealing material, and the odor components migrate to the products manufactured in the subsequent processes via the sealing material. There is a risk of quality degradation. For this reason, in addition to being excellent in chemical resistance and heat resistance, a sealing material used in such a field is also required to have low flavoring.

As a material for forming such a sealing material excellent in chemical resistance, heat resistance, low fragrance, etc., fluororesin and fluororubber are widely used.
For example, Patent Document 1 discloses a porous fluororesin outer member made of polytetrafluoroethylene (PTFE) or the like so as to cover the outer surface of a rubber core member such as ethylene propylene rubber (EDPM). A formed composite sealing material is disclosed. Patent Document 2 discloses an annular core containing organic fiber, inorganic fiber, inorganic powder, and binder in a fluororesin jacket composed of PTFE, tetrafluoroethylene-perfluoroalkyl vinyl ether (PFA) resin, or the like. A fluororesin-wrapped gasket in which is inserted is disclosed. Patent Document 3 discloses a sanitary piping gasket obtained by melt-molding a fluororesin such as PFA.

In addition, perfluoro rubber (FFKM) is excellent in chemical resistance, heat resistance, low fragrance and the like, but is very expensive. Therefore, studies have been made to achieve both improvement in performance and cost reduction.
For example, as a fluororubber composition for the purpose of obtaining a sealing material with reduced fragrance properties, a glass filler and / or a true spherical nonporous silica (such as vinylidene fluoride (VdF) -based rubber) A fluororubber composition containing an amorphous silicon dioxide) filler (see, for example, Patent Document 4), and a fluororubber composition in which a boron nitride filler is blended with fluororubber (see, for example, Patent Document 5). Formulated with spherical nonporous silica (amorphous silicon dioxide) filler, which may be surface modified to fluororubber, fine powder fluororesin filler, organic peroxide vulcanizing agent and co-crosslinking agent Proposed fluororubber compositions (see, for example, Patent Document 6) have been proposed. These fluororubber compositions are said to be able to obtain a sealing material that is less expensive than FFKM and excellent in non-fragrance, heat resistance, and chemical resistance.
In addition, a fluororubber composition containing a fluororubber and a fluorosurfactant has been studied as a rubber member having further improved low flavor compared to such a sealing material (for example, Patent Document 7). reference.).

JP 2006-29376 A JP 2009-24877 A JP 2000-303058 A JP 2005-306931 A JP 2006-160898 A JP 2007-154043 A JP 2011-42714 A

By the way, the member by which the outstanding low fragrance property is calculated | required is not limited to a sealing material as mentioned above. For example, when a product or its raw material is transported by a roll, a belt, a hose or the like, it is not desirable that the odor component of the article transported in the previous process is deteriorated because quality is deteriorated. For this reason, from the viewpoint of preventing quality deterioration, members such as rolls, belts, and hoses are also preferably formed using a material with low flavor.
As described above, the conventional technology has room for contrivance for developing a material excellent in low flavoring that can be widely applied to a conveying member.

The present invention has been made in view of the above situation, and an object of the present invention is to provide a fluorine-containing elastomer composition capable of obtaining a conveying member with sufficiently reduced fragrance properties. .

The present inventor has studied various materials excellent in low fragrance properties, and when using a cross-linked product of a fluorine-containing elastomer composition as a material, a hydrocarbon system such as a specific cross-linking agent or a cross-linking aid in the use environment. It was found that the leakage of the compound to the surface of the cross-linked product contributed to the occurrence of the flavoring phenomenon. And when it controlled so that a hydrocarbon type compound might not leak substantially on the surface of a crosslinked material, even when the crosslinked material was applied to the member for conveyance, it discovered that fragrance property could fully be suppressed. Moreover, since such a conveyance member can be easily manufactured when it is obtained by applying a fluorine-containing elastomer composition, it has been found that both performance and productivity can be achieved. . Further, such a conveying member can be suitably applied to various fields as a conveying member for conveying various articles such as food, beverage products, cosmetics, inks, pigments and paper. As a result, the inventors have arrived at the present invention by conceiving that the above problems can be solved brilliantly.

That is, the present invention is a fluorine-containing elastomer composition containing a crosslinkable fluorine-containing elastomer, wherein the hydrocarbon compound does not substantially leak onto the surface of the crosslinked product of the composition. It is a fluorine elastomer composition.

The present invention is also a conveying member obtained by applying the fluorine-containing elastomer composition, wherein the conveying member is characterized in that at least a part of the surface is composed of a crosslinked product of the composition. It is also a conveying member.
The present invention is described in detail below.

The fluorine-containing elastomer composition of the present invention (hereinafter also simply referred to as a composition) includes a crosslinkable fluorine-containing elastomer (hereinafter also simply referred to as a fluorine-containing elastomer), and the composition is crosslinked. The hydrocarbon compound does not substantially leak out on the surface of the resulting crosslinked product. Thereby, the cross-linked product becomes excellent in low flavor.
The composition may further contain other components as long as the fluorine-containing elastomer is an essential component, and one or more of the other components can be used.

In this specification, “flavoring” includes both a phenomenon in which the odor component of a product or raw material moves to a member, and a phenomenon in which the odor component transferred to a member moves to another product or raw material.

Specific examples of the hydrocarbon-based compound include compounds having a hydrocarbon moiety in the structure among a crosslinking agent and a crosslinking accelerator (crosslinking aid) used for crosslinking the composition. .

In the present specification, “the hydrocarbon compound does not substantially leak” means that the carbon concentration on the surface of the crosslinked product is lower than the carbon concentration (theoretical carbon concentration) calculated from the polymer composition.
The carbon concentration on the cross-linked product surface and the theoretical carbon concentration can be measured or calculated by the method used in Examples described later.

Examples of a method for suppressing leakage of the hydrocarbon-based compound to the surface of the crosslinked product include (1) a method of reducing the amount of a crosslinking agent, a crosslinking accelerator, and the like, and (2) it is difficult to leak to the surface of the crosslinked product. Or a method of selecting a cross-linking agent, a cross-linking accelerator or the like that substantially does not contain a hydrocarbon moiety, and (3) a method of adding a filler to the above composition. These methods may be used alone or in combination of two or more as necessary.

The method (1) is intended to reduce the amount of leakage by reducing the amount of the crosslinking agent or the like remaining in the crosslinked product, is relatively easy to leak (release), and has high crosslinkability ( This is particularly effective when a crosslinking agent (which can be sufficiently crosslinked even in a small amount) is used.

The method (2) is capable of forming a strong cross-linked structure, so that it is difficult to leak out, or the structure does not contain a hydrocarbon moiety (that is, does not correspond to the hydrocarbon compound) and leaks out. Furthermore, the use of a cross-linking agent that hardly causes a fragrance phenomenon is intended to reduce the fragrance property. This is particularly effective when it is appropriate to use the specific cross-linking agent as described above in consideration of the type and application of the fluorine-containing elastomer to be used.

In the above method (3), it is considered that the amount of leakage of the crosslinking agent or the like can be reduced by adsorbing the free crosslinking agent or the like by the filler such as carbon black added to the fluorine-containing elastomer composition. . Method (3) is particularly effective when it is necessary to use a cross-linking agent that is relatively easy to leak (release) and it is difficult to sufficiently reduce the amount of use.

By adopting at least one of the above methods (1) to (3), it is possible to control so that the hydrocarbon-based compound does not substantially leak onto the surface of the resulting crosslinked product, and as a result, the crosslinked product Can be sufficiently reduced.

The crosslinkable fluorine-containing elastomer in the present invention is not particularly limited and may be appropriately selected depending on the application. For example, fluorine rubber (a), thermoplastic fluorine rubber (fluorine-containing multi-segmented polymer) ( b), and rubber compositions comprising these rubbers. Of these, fluororubber (a) is preferred.

Examples of the fluororubber (a) include non-perfluorofluororubber (a-1) and perfluorofluororubber (a-2). Specific examples of these will be described later.

The fluorine-containing elastomer composition of the present invention preferably contains a crosslinking agent. Thereby, a crosslinked product can be obtained by a crosslinking reaction using a crosslinking agent.
Examples of the crosslinking system that can be employed in the present invention include a peroxide crosslinking system, a polyol crosslinking system, a polyamine crosslinking system, a triazine crosslinking system, an oxazole crosslinking system, an imidazole crosslinking system, and a thiazole crosslinking system.

When the fluorine-containing elastomer is a non-perfluoro fluorine rubber (a-1), it is preferable to employ a peroxide crosslinking system, a polyol crosslinking system, or a polyamine crosslinking system. When the fluorine-containing elastomer is a perfluoro fluorine rubber (a-2), any of the above-mentioned crosslinking systems can be preferably employed. Among them, a triazine crosslinking system, an oxazole crosslinking system, an imidazole crosslinking system, or a thiazole crosslinking system can be used. It is preferable to adopt.

Peroxide crosslinking can be performed by using peroxide-crosslinkable fluorine-containing elastomer and an organic peroxide as a crosslinking agent.

In the peroxide crosslinking system, a crosslinking accelerator (crosslinking aid) may be used. The crosslinking accelerator may be a compound having a reaction activity with respect to peroxy radicals and polymer radicals.

When the peroxide crosslinking is performed, the amount of the crosslinking agent is preferably 0.05 to 10 parts by mass, and more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer. When the amount of the crosslinking agent is less than 0.05 parts by mass, the crosslinkable fluorine-containing elastomer tends not to be sufficiently crosslinked. When the amount exceeds 10 parts by mass, the crosslinking agent tends to leak to the surface of the crosslinked product, and the flavor of the crosslinked product is increased. There is a tendency to worsen sex.

Moreover, it is preferable that the compounding quantity of the crosslinking accelerator in peroxide bridge | crosslinking is 0.01-10 mass parts with respect to 100 mass parts of fluorine-containing elastomers, and it is more preferable that it is 0.1-5.0 mass parts. preferable. If the crosslinking accelerator is less than 0.01 parts by mass, the crosslinking time tends to be unpractical, and if it exceeds 10 parts by mass, the crosslinking time becomes too fast and the crosslinked product surface is crosslinked. The accelerator tends to leak out and tends to deteriorate the flavor of the crosslinked product.

Polyol crosslinking can be performed by using a polyol-crosslinkable fluorine-containing elastomer and a polyhydroxy compound as a crosslinking agent.

When the crosslinking agent is a polyhydroxy compound, it is preferable to use a crosslinking accelerator in combination. A crosslinking accelerator accelerates | stimulates the production | generation of the intramolecular double bond in the dehydrofluorination reaction of a polymer principal chain, and the addition of the polyhydroxy compound to the produced | generated double bond.

The blending amount of the crosslinking agent in the case of polyol crosslinking is preferably 0.05 to 10 parts by mass and more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer. When the amount of the crosslinking agent is less than 0.05 parts by mass, the crosslinkable fluorine-containing elastomer tends not to be sufficiently crosslinked. When the amount exceeds 10 parts by mass, the crosslinking agent tends to leak to the surface of the crosslinked product, and the flavor of the crosslinked product is increased. There is a tendency to worsen sex.

Moreover, it is preferable that the compounding quantity of the crosslinking accelerator in polyol bridge | crosslinking is 0.01-8 mass parts with respect to 100 mass parts of fluorine-containing elastomers, More preferably, it is 0.02-5 mass parts. When the crosslinking accelerator is less than 0.01 parts by mass, the crosslinking of the fluorine-containing elastomer does not proceed sufficiently, and the heat resistance of the resulting crosslinked product tends to decrease. There is a tendency for the crosslinking accelerator to easily leak to the surface of the product, and to deteriorate the flavor of the crosslinked product.

Polyamine crosslinking can be performed by using a polyamine-crosslinkable fluorine-containing elastomer and a polyamine compound as a crosslinking agent.

The blending amount of the crosslinking agent when performing polyamine crosslinking is preferably 0.05 to 10 parts by mass, more preferably 1 to 5 parts by mass with respect to 100 parts by mass of the fluorine-containing elastomer. When the amount of the crosslinking agent is less than 0.05 parts by mass, the crosslinkable fluorine-containing elastomer tends not to be sufficiently crosslinked. When the amount exceeds 10 parts by mass, the crosslinking agent tends to leak to the surface of the crosslinked product, and the flavor of the crosslinked product is increased. There is a tendency to worsen sex.

Triazine crosslinking, oxazole crosslinking, imidazole crosslinking, and thiazole crosslinking are performed by using a fluorine-containing elastomer that can be crosslinked by these crosslinking systems and an oxazole crosslinking agent, imidazole crosslinking agent, thiazole crosslinking agent, or triazine crosslinking agent. be able to.
Since these crosslinking agents form a strong crosslinked structure with the fluorine-containing elastomer, it is difficult to leak to the surface of the crosslinked product, and the fragrance of the crosslinked product can be suppressed. Therefore, it can be particularly suitably used when the leakage of the hydrocarbon compound is suppressed by the method (2).
In addition, the heat resistance of the crosslinked product can be significantly improved.

It is preferable that the compounding quantity of the crosslinking agent in a triazine bridge | crosslinking, an oxazole bridge | crosslinking, an imidazole bridge | crosslinking, and a thiazole bridge | crosslinking is 0.05-10 mass parts with respect to 100 mass parts of fluorine-containing elastomers, 0.5-5 masses. More preferably, it is a part. When the amount of the crosslinking agent is less than 0.05 parts by mass, the crosslinkable fluorine-containing elastomer tends not to be sufficiently crosslinked. When the amount exceeds 10 parts by mass, the crosslinking agent tends to leak to the surface of the crosslinked product, and the flavor of the crosslinked product is increased. There is a tendency to worsen sex.

The fluorine-containing elastomer composition of the present invention may contain a filler as necessary. For example, as shown in the said method (3), when the said composition contains a filler, the leakage of the hydrocarbon type compound to the surface of a crosslinked material can be suppressed.
In particular, when the fluorine-containing elastomer is perfluoro fluorine rubber (a-2) and a peroxide crosslinking system is employed, the fluorine-containing elastomer composition of the present invention preferably contains a filler.

The blending amount of the filler can be determined according to, for example, the crosslinking system to be employed.
When employing peroxide crosslinking, the amount is preferably 1 part by mass or more with respect to 100 parts by mass of the fluorine-containing elastomer. If the amount is too small, the adsorption function of the hydrocarbon compound may not be sufficiently exhibited, and the function as a filler may be hardly exhibited. A more preferable lower limit of the blending amount is 5 parts by mass. Moreover, a preferable upper limit is 50 mass parts, and when it exceeds more than this, hardness will become very high and the characteristic as an elastic body may be lost. The upper limit of the more preferable compounding quantity is 15-20 mass parts from the point with the favorable hardness at the time of setting it as the member for conveyance.

When employing polyol crosslinking, the amount is preferably 1 part by mass or more and more preferably 5 parts by mass or more with respect to 100 parts by mass of the fluorine-containing elastomer. Moreover, 50 mass parts or less are preferable, 30 mass parts or less are more preferable, and 20 mass parts or less are still more preferable.
When employing polyamine crosslinking, the amount is preferably 1 part by mass or more and more preferably 5 parts by mass or more with respect to 100 parts by mass of the fluorine-containing elastomer. Moreover, 50 mass parts or less are preferable, 30 mass parts or less are more preferable, and 20 mass parts or less are still more preferable.

When employing triazine crosslinking, oxazole crosslinking, imidazole crosslinking, or thiazole crosslinking, the amount is preferably 1 part by mass or more and more preferably 5 parts by mass or more with respect to 100 parts by mass of the fluorine-containing elastomer. Moreover, 50 mass parts or less are preferable, 30 mass parts or less are more preferable, and 20 mass parts or less are still more preferable.

Hereinafter, the fluorine-containing elastomer, the crosslinking agent, the filler and the like that can be used in the present invention will be described in more detail with specific examples.

Examples of the non-perfluorofluororubber (a-1) include vinylidene fluoride (VdF) fluororubber, tetrafluoroethylene (TFE) / propylene (Pr) fluororubber, tetrafluoroethylene (TFE) / propylene / vinylidene fluoride. Ride (VdF) fluorine rubber, ethylene / hexafluoropropylene (HFP) fluorine rubber, ethylene / hexafluoropropylene (HFP) / vinylidene fluoride (VdF) fluorine rubber, ethylene / hexafluoropropylene (HFP) / tetrafluoro Ethylene (TFE) -based fluororubber, fluorosilicone-based fluororubber, fluorophosphazene-based fluororubber and the like can be mentioned, and these can be used alone or in any combination as long as the effects of the present invention are not impaired. . Of these, vinylidene fluoride fluororubber and tetrafluoroethylene / propylene fluororubber are preferable.

The vinylidene fluoride-based fluororubber is a fluorine-containing elastic copolymer comprising 45 to 85 mol% of vinylidene fluoride and 55 to 15 mol% of at least one other monomer copolymerizable with vinylidene fluoride. Refers to a polymer. Preferably, it refers to a fluorinated elastic copolymer comprising 50 to 80 mol% of vinylidene fluoride and 50 to 20 mol% of at least one other monomer copolymerizable with vinylidene fluoride.

Examples of at least one other monomer copolymerizable with the vinylidene fluoride include tetrafluoroethylene (TFE), chlorotrifluoroethylene (CTFE), trifluoroethylene, hexafluoropropylene (HFP), Fluorinated monomers such as fluoropropylene, tetrafluoropropylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutene, perfluoro (alkyl vinyl ether) (PAVE), vinyl fluoride, non-fluorine such as ethylene, propylene, alkyl vinyl ether Monomer. These can be used alone or in any combination. Among these, it is preferable to use tetrafluoroethylene, hexafluoropropylene, and perfluoro (alkyl vinyl ether).

Examples of the perfluoro (alkyl vinyl ether) in this case include perfluoro (methyl vinyl ether), perfluoro (propyl vinyl ether), and the like. These may be used alone or within a range not impairing the effects of the present invention. They can be used in combination.

Specific examples of the vinylidene fluoride fluororubber include VdF-HFP rubber, VdF-HFP-TFE rubber, VdF-CTFE rubber, VdF-CTFE-TFE rubber, and the like.

Vinylidene fluoride-based fluororubber can be obtained by a conventional method.

The tetrafluoroethylene / propylene-based fluororubber is a fluorine-containing elastic copolymer composed of 45 to 70 mol% of tetrafluoroethylene, 55 to 30 mol% of propylene, and 0 to 5 mol% of a monomer that gives a crosslinking site. Refers to coalescence.

Examples of the monomer that gives the cross-linked site include perfluoro (6,6-dihydro-6-iodo-3-oxaxane as described in JP-B-5-63482 and JP-A-7-316234. -1-hexene) and iodine-containing monomers such as perfluoro (5-iodo-3-oxa-1-pentene), bromine-containing monomers described in JP-A-4-505341, special table Examples include nitrile group-containing monomers, carboxyl group-containing monomers, and alkoxycarbonyl group-containing monomers as described in JP-A-4-505345 and JP-A-5-500070.

Tetrafluoroethylene / propylene-based fluororubber can also be obtained by a conventional method.

Examples of commercially available non-perfluorofluororubber (a-1) include Daiel G-800 series and G-900 series manufactured by Daikin Industries, Ltd.

Examples of the perfluoro fluorine rubber (a-2) include TFE-containing perfluoro rubber, such as TFE / perfluoro (alkyl vinyl ether) (PAVE) / a fluorine-containing elastic copolymer comprising a monomer that provides a crosslinking site. Can be mentioned. The composition is preferably 45 to 90/10 to 50/0 to 5 (mol%), more preferably 45 to 80/20 to 50/0 to 5, and still more preferably 53 to 70. / 30 to 45/0 to 2. When the composition is out of the range, the properties as a rubber elastic body are lost, and the properties tend to be similar to those of a resin.

Examples of PAVE in this case include perfluoro (methyl vinyl ether) (PMVE), perfluoro (propyl vinyl ether) (PPVE), etc., and these may be used alone or within a range that does not impair the effects of the present invention. They can be used in combination.

Examples of the monomer that gives the crosslinking site include, for example, the general formula (1):
_{CX 2 = CX-R f CHRI} (1)
(Wherein X is H, F or CH ₃ , R _f is a fluoroalkylene group, perfluoroalkylene group, fluoropolyoxyalkylene group or perfluoropolyoxyalkylene group, R is H or CH ₃ ) Containing monomer, general formula (2):
_{CF 2 = CFO (CF 2 CF} (CF 3)) m -O- (CF 2) n -Y (2)
(Wherein, m is an integer of 0 to 5, n is an integer of 1 to 3, Y is a nitrile group, a carboxyl group, an alkoxycarbonyl group, or a bromine atom). Can be used alone or in any combination as long as the effects of the present invention are not impaired. These iodine atoms, nitrile groups, carboxyl groups, alkoxycarbonyl groups, and bromine atoms function as crosslinking points.

The perfluoro fluororubber (a-2) can also be produced by a conventional method.

Specific examples of such perfluoro fluororubber (a-2) include International Publication No. 97/24381, Japanese Patent Publication No. 61-57324, Japanese Patent Publication No. 4-81608, Japanese Patent Publication No. 5-13961, and the like. Examples thereof include the fluororubber described.

The thermoplastic fluororubber (b) is composed of an elastomeric fluoropolymer chain segment and a non-elastomeric fluoropolymer chain segment described in WO 03/051999 pamphlet, and contains an elastomeric fluoropolymer chain. The fluorine-containing multi-segmented polymer (b-1) in which 90 mol% or more of the respective structural units of the segment and the non-elastomeric fluorine-containing polymer chain segment are perhaloolefin, the elastomeric fluorine-containing polymer chain segment and the non-elastomeric-containing polymer It consists of fluoropolymer chain segments, and 90 mol% or more of the structural units of the elastomeric fluoropolymer chain segments are perhaloolefins, and the non-elastomeric fluoropolymer chain segments are less than 90 mol% as structural units. It consists of a fluorine-containing multi-segmented polymer (b-2) containing perhaloolefin, and an elastomeric fluorine-containing polymer chain segment and a non-elastomeric fluorine-containing polymer chain segment. The composition contains less than 90 mol% perhaloolefin, and 90 mol% or more of the structural units of the non-elastomeric fluorine-containing polymer chain segment are perhaloolefins or contain less than 90 mol% perhaloolefin as a structural unit. Fluorine multi-segmented polymer (b-3) can be mentioned.

The manufacturing method and the obtaining method of these thermoplastic fluororubbers (b-1) to (b-3) described in International Publication No. 03/051999 pamphlet and the like are also employed in the present invention.

The crosslinkable fluorine-containing elastomer in the present invention may have a cross-linked site. Examples of the crosslinking site include the above crosslinking sites such as a carboxyl group obtained by modifying a polymerization initiator such as ammonium persulfate, such as an iodine atom (which can be produced by an iodine transfer polymerization method) present at the end of the main chain or side chain. And the like, and the like.

Examples of such a monomer include perfluoro (6,6-dihydro-6-iodo-3-oxa-1-) described in JP-B-5-63482 and JP-A-7-316234. Hexene) and iodine-containing monomers such as perfluoro (5-iodo-3-oxa-1-pentene), bromine-containing monomers described in JP-A-4-505341, Nitrile group-containing monomers, carboxyl group-containing monomers, alkoxycarbonyl group-containing monomers and the like described in JP-A-505345 and JP-A-5-500070 are suitable.

Examples of the crosslinkable fluorine-containing elastomer in the present invention include fluorosilicone rubber and the like in addition to those described above.

The organic peroxide that can be used as a crosslinking agent in peroxide crosslinking may be an organic peroxide that can easily generate a peroxy radical in the presence of heat or a redox system. 1,1-bis (t-butylperoxy) -3,5,5-trimethylcyclohexane, 2,5-dimethylhexane-2,5-dihydroperoxide, di-t-butyl peroxide, t-butylcumylper Oxide, dicumyl peroxide, α, α-bis (t-butylperoxy) -p-diisopropylbenzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl -2,5-di (t-butylperoxy) -hexyne-3, benzoyl peroxide, t-butylperoxybenzene, 2,5-dimethyl-2, Examples thereof include 5-di (benzoylperoxy) hexane, t-butylperoxymaleic acid, t-butylperoxyisopropyl carbonate, and the like. Among them, preferred is a dialkyl type. Furthermore, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane is particularly preferable. In general, the type and amount of the organic peroxide are determined in consideration of the amount of active —O—O—, decomposition temperature and the like.

In addition, the crosslinking accelerator used in the peroxide crosslinking system may be a compound having a reactive activity with respect to a peroxy radical and a polymer radical, for example, CH ₂ ═CH—, CH ₂ ═CHCH ₂ —, CF _2. Examples thereof include polyfunctional compounds having a functional group such as ═CF—. Specifically, for example, triallyl cyanurate, triallyl isocyanurate (TAIC), triacryl formal, triallyl trimellitate, N, N′-n-phenylenebismaleimide, 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-triazine 2,4,6 -Trione), tris (diallylamine) -S-triazine, triallyl phosphite, N, N-diallylacrylamide, 1,6-divinyldodecafluorohexane and the like.

The fluorine-containing elastomer capable of peroxide crosslinking is not particularly limited as long as it is a fluorine-containing elastomer having a site capable of peroxide crosslinking. The site capable of peroxide crosslinking is not particularly limited, and examples thereof include a site having a propylene (P) unit, an iodine atom, and a bromine atom.

As a polyhydroxy compound that can be used as a crosslinking agent in polyol crosslinking, a polyhydroxy aromatic compound is preferably used from the viewpoint of excellent heat resistance.
The polyhydroxy aromatic compound is not particularly limited. For example, 2,2-bis (4-hydroxyphenyl) propane (hereinafter referred to as bisphenol A), 2,2-bis (4-hydroxyphenyl) perfluoropropane. (Hereinafter referred to as bisphenol AF), resorcin, 1,3-dihydroxybenzene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 4,4′-dihydroxydiphenyl, 4,4 ′ -Dihydroxystilbene, 2,6-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) te Lafluorodichloropropane, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl ketone, tri (4-hydroxyphenyl) methane, 3,3 ′, 5,5′-tetrachlorobisphenol A, 3,3 Examples include ', 5,5'-tetrabromobisphenol A. These polyhydroxy aromatic compounds may be an alkali metal salt, an alkaline earth metal salt, or the like, but when the copolymer is coagulated using an acid, it is preferable not to use the metal salt.

Examples of crosslinking accelerators that can be used in polyol crosslinking include onium compounds. Among onium compounds, ammonium compounds such as quaternary ammonium salts, phosphonium compounds such as quaternary phosphonium salts, oxonium compounds, sulfonium compounds, It is preferably at least one selected from the group consisting of cyclic amines and monofunctional amine compounds, and is at least one selected from the group consisting of quaternary ammonium salts and quaternary phosphonium salts. Is more preferable.

The quaternary ammonium salt is not particularly limited. For example, 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, 8-dodecyl-1,8-diazabicyclo [ , 4,0] -7-undecenium hydroxide, 8-eicosyl-1,8-diazabicyclo [5,4,0] -7-undecenium chloride, 8-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 preferable from the viewpoint of excellent crosslinkability and physical properties of the molded product.

The quaternary phosphonium salt is not particularly limited. For example, tetrabutylphosphonium chloride, benzyltriphenylphosphonium chloride (hereinafter referred to as BTPPC), benzyltributylphosphonium chloride, benzyltributylphosphonium chloride, tributylallylphosphonium chloride, tributyl. Examples include 2-methoxypropylphosphonium chloride, benzylphenyl (dimethylamino) phosphonium chloride, and among them, benzyltriphenylphosphonium chloride (BTPPC) is preferable from the viewpoint of excellent crosslinkability and physical properties of the molded product.

Further, as a crosslinking accelerator, a quaternary ammonium salt, a solid solution of a quaternary phosphonium salt and bisphenol AF, or a chlorine-free crosslinking accelerator disclosed in JP-A-11-147891 can also be used.

The polyol-crosslinkable fluorine-containing elastomer is not particularly limited as long as it is a fluorine-containing elastomer having a polyol-crosslinkable site. The polyol-crosslinkable site is not particularly limited, and examples thereof include a site having a vinylidene fluoride (VdF) unit. Examples of the method for introducing the crosslinking site include a method of copolymerizing a monomer that gives a crosslinking site during polymerization of the fluorine-containing elastomer.

Examples of polyamine compounds that can be used as a crosslinking agent in polyamine crosslinking include hexamethylene diamine carbamate, N, N′-dicinnamylidene-1,6-hexamethylene diamine, and 4,4′-bis (aminocyclohexyl) methane carbamate. Can be mentioned. Among these, N, N′-dicinnamylidene-1,6-hexamethylenediamine is preferable.

The fluorine-containing elastomer capable of crosslinking with polyamine is not particularly limited as long as it is a fluorine-containing elastomer having a polyamine-crosslinkable site. The polyamine-crosslinkable site is not particularly limited, and examples thereof include a site having a vinylidene fluoride (VdF) unit. Examples of the method for introducing the crosslinking site include a method of copolymerizing a monomer that gives a crosslinking site during polymerization of the fluorine-containing elastomer.

Examples of the crosslinking agent used for triazine crosslinking include organotin compounds such as tetraphenyltin and triphenyltin, and urea, ammonium salts, and silicon nitride. Among these, silicon nitride is preferable because it does not include a hydrocarbon moiety in the structure, and thus can significantly suppress leakage of the hydrocarbon-based compound.

Examples of the crosslinking agent used in the oxazole crosslinking system, imidazole crosslinking system, and thiazole crosslinking system include, for example, the general formula (3):

(In the formula, R ¹ is —SO ₂ —, —O—, —CO—, an alkylene group having 1 to 6 carbon atoms, a perfluoroalkylene group having 1 to 10 carbon atoms, or a single bond, R ² and R ³ one is -NH ₂ the other is _-NH 2, -OH or -SH, bisdiaminophenyl crosslinking agent represented by preferably any of ^{R 2} and ^{R 3} is -NH _2.), bis amino Phenolic crosslinking agent, bisaminothiophenol crosslinking agent, general formula (4):

(In the formula, R ¹ is the same as above. R ⁴ represents the following general formula (5):

It is a compound represented by these. ) Bisamidrazone crosslinking agents and bisamidoxime crosslinking agents represented by formula (6):

(Wherein R _f ′ is a C 1-10 perfluoroalkylene group) or general formula (7):

(Wherein, n is an integer of 1 to 10), such as bisamidrazone crosslinking agents and bisamidoxime crosslinking agents. These bisaminophenol-based crosslinking agents, bisaminothiophenol-based crosslinking agents, bisdiaminophenyl-based crosslinking agents, etc. are conventionally used for crosslinking systems having a nitrile group as a crosslinking point. It reacts with the group to form an oxazole ring, a thiazole ring and an imidazole ring to give a cross-linked product.

Among these cross-linking agents, the heat resistance is particularly excellent, the cross-linking reactivity is good, and the synthesis is relatively easy.

(In the formula, R ⁵ is a fluorine atom or a monovalent organic group.) A bisdiaminophenyl-based crosslinking agent having at least two bisamino-crosslinkable functional groups. Examples of the functional group capable of reacting with the crosslinkable functional group include a nitrile group, a carboxyl group, and an alkoxycarbonyl group, and an imidazole ring is formed by the reaction.

Furthermore, a more preferable crosslinking agent is represented by the general formula (9):

(In the formula, R ⁶ is a monovalent organic group other than hydrogen or a fluorine atom. R ⁷ is —SO ₂ —, —O—, —CO—, an alkylene group which may be substituted; ):

Or a single bond. ).

R ⁶ is preferably a substituent that forms an N—R ⁶ bond having oxidation resistance higher than that of an N—H bond. Here, the “substituent that forms an N—R ⁶ bond having higher oxidation resistance than an N—H bond” means a compound that is less oxidizable than a compound having an N—H bond when an imidazole ring is formed. It refers to a substituent that forms an existing N—R ⁶ bond.

Such R ⁶ includes, but is not limited to, an optionally substituted aliphatic hydrocarbon group, an optionally substituted phenyl group, or a benzyl group.

As a specific example, for example, at least one of R ⁶ is a lower alkyl group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms such as —CH ₃ , —C ₂ H ₅ , —C ₃ H _7, etc .; —CF ₃ , —C ₂ F ₅ , —CH ₂ F, —CH ₂ CF ₃ , —CH ₂ C ₂ F _5, etc., a fluorine atom-containing lower alkyl group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms; phenyl group; benzyl group; _{6 F 5, -CH 2 C 6} F 5 such as a phenyl group or a benzyl group 1-5 hydrogen atoms with fluorine atoms is _{substituted; -C 6 H 5-n (} CF 3) n, -CH 2 C Examples thereof include a phenyl group or a benzyl group in which 1 to 5 hydrogen atoms are substituted with —CF ₃ such as ₆ H _5-n (CF ₃ ) _n (n is an integer of 1 to 5).

Of these, a phenyl group and —CH ₃ are preferred because they are particularly excellent in heat resistance, have good crosslinking reactivity, and are relatively easy to synthesize.

In the compound of the general formula (9), preferred specific examples of the optionally substituted alkylene group for R ⁷ include, but are not limited to, for example, an unsubstituted alkylene group having 1 to 6 carbon atoms or 1 to 10 carbon atoms. Perfluoroalkylene group, etc., and the perfluoroalkylene group may be represented by the general formula (11):

The group etc. which are represented by these are mentioned. As R ⁷ , those known as examples of bisdiaminophenyl compounds in JP-B-2-59177, JP-A-8-120146 and the like can be used.

R ⁷ may be bonded to any position of the left and right benzene rings, but since synthesis is easy and the crosslinking reaction proceeds easily, either the NH ₂ group or the NHR ⁷ group is in the para position. It is preferable to combine so that

Particularly preferred crosslinking agents are those represented by the general formula (12):

(Wherein R ⁸ is the same or different and each is an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 10 carbon atoms containing a fluorine atom, a phenyl group, a benzyl group, a fluorine atom or —CF ₃ . It is a phenyl group or benzyl group in which 1 to 5 hydrogen atoms are substituted.

Examples of the compound represented by the general formula (12) include 2,2-bis- [3-amino-4- (N-methylamino) phenyl] hexafluoropropane, 2,2-bis- [3-amino. -4- (N-ethylamino) phenyl] hexafluoropropane, 2,2-bis- [3-amino-4- (N-propylamino) phenyl] hexafluoropropane, 2,2-bis- [3-amino -4- (N-phenylamino) phenyl] hexafluoropropane, 2,2-bis- [3-amino-4- (N-perfluorophenylamino) phenyl] hexafluoropropane, 2,2-bis- [3 -Amino-4- (N-benzylamino) phenyl] hexafluoropropane, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (generic name) Bis (aminophenol) AF), 2,2-bis (3-amino-4-mercaptophenyl) hexafluoropropane, tetraaminobenzene, bis-3,4-diaminophenylmethane, bis-3,4-diaminophenyl ether 2,2-bis (3,4-diaminophenyl) hexafluoropropane and the like.

Examples of the fluorine-containing elastomer that can be cross-linked by triazine cross-linking, oxazole cross-linking, imidazole cross-linking, and thiazole cross-linking can include a fluoro rubber made of a copolymer containing a copolymer unit derived from a monomer that gives a cross-linking site. .

The fluorine-containing elastomer composition of the present invention can be subjected to high energy ray crosslinking without adding a crosslinking agent or the like. As the crosslinking source, X-rays, α rays, β rays, γ rays, electron beams, proton beams, deuteron beams, ultraviolet rays, and the like are used. The irradiation amount in this case may be 0.1 to 50 Mrad. Moreover, irradiation temperature should just be -20-100 degreeC. The irradiation atmosphere may be in the presence of air, nitrogen, argon, helium or under vacuum.

The filler is not limited as long as it can adsorb the hydrocarbon-based compound. For example, it is made of engineering plastic such as polyarylate, polysulfone, polyethersulfone, polyphenylene sulfide, polyoxybenzoate, polytetrafluoroethylene powder, etc. Organic oxide fillers: Metal oxide fillers such as aluminum oxide, silicon oxide, yttrium oxide and titanium oxide; Metal carbide fillers such as silicon carbide and aluminum carbide; Metal nitride fillers such as silicon nitride and aluminum nitride; Aluminum fluoride and fluoride Inorganic fillers such as carbonized carbon, barium sulfate, carbon black, silica, clay, and talc can be used, and one or more of these can be used.
Especially, it is preferable to use carbon black at the point which is excellent in the adsorptive power of the said hydrocarbon type compound.

Examples of the carbon black include furnace black, acetylene black, thermal black, channel black, graphite, and the like. Specifically, for example, SAF-HS (N ₂ SA: 142 m ² / g, DBP: 130 ml / 100 g), SAF (N ₂ SA: 142 m ² / g, DBP: 115 ml / 100 g), N234 (N ₂ SA: 126 m ² / g, DBP: 125 ml / 100 g), ISAF (N ₂ SA: 119 m ² / g, DBP: 114 ml) / 100 g), ISAF-LS (N ₂ SA: 106 m ² / g, DBP: 75 ml / 100 g), ISAF-HS (N ₂ SA: 99 m ² / g, DBP: 129 ml / 100 g), N339 (N ₂ SA: 93m ² / g, DBP: 119ml / 100g), HAF-LS (N ₂ SA: 84 m ² / g, DBP: 75 ml / 100 g), HAS-HS (N ₂ SA: 82 m ² / g, DBP: 126 ml / 100 g), HAF (N ₂ SA: 79 m ² / g, DBP: 101 ml / 100 g), N351 (N ₂ SA: 74 m ² / g, DBP: 127 ml / 100 g), LI-HAF (N ₂ SA: 74 m ² / g, DBP: 101 ml / 100 g), MAF-HS (N ₂ SA : 56 m ² / g, DBP: 158 ml / 100 g), MAF (N ₂ SA: 49 m ² / g, DBP: 133 ml / 100 g), FEF-HS (N ₂ SA: 42 m ² / g, DBP: 160 ml / 100 g) , FEF (N ₂ SA: 42 m ² / g, DBP: 115 ml / 100 g), SRF-HS (N ₂ SA: 32 m ² / g, DBP: 140 ml / 100 g), SRF-HS (N ₂ SA: 29 m ² / g, DBP: 152 ml / 100 g), GPF (N ₂ SA: 27 m ² / g, DBP: 87 ml / 100 g), SRF (N ₂ SA: 27 m ² / g, DBP: 68 ml / 100 g), SRF-LS (N ₂ SA: 23 m ² / g, DBP: 51 ml / 100 g), FT (N ₂ SA: 19 m ² / g, DBP: 42 ml / 100 g), MT (N ₂ SA: 8 m ² / g, DBP: 43 ml / 100 g). These carbon blacks may be used alone or in combination of two or more.

Among these, carbon black having a nitrogen adsorption specific surface area (N ₂ SA) of 5 to 180 m ² / g and a dibutyl phthalate (DBP) oil absorption of 40 to 180 ml / 100 g is preferable.

When the nitrogen adsorption specific surface area (N ₂ SA) is smaller than 5 m ² / g, mechanical properties when blended with rubber tend to be reduced. From this viewpoint, the nitrogen adsorption specific surface area (N ₂ SA) is 10 m ^2. / G or more is preferable, 20 m ² / g or more is more preferable, and 25 m ² / g or more is particularly preferable. The upper limit is preferably 180 m ² / g from the viewpoint of easy availability.

When the dibutyl phthalate (DBP) oil absorption is less than 40 ml / 100 g, the mechanical properties when blended with rubber tend to decrease. From this viewpoint, 50 ml / 100 g or more, further 60 ml / 100 g or more, particularly 80 ml. / 100 g is preferred. From the viewpoint of easy availability, the upper limit is preferably 175 ml / 100 g, more preferably 170 ml / 100 g.

The fluorine-containing elastomer composition of the present invention is a normal compounding agent blended in the fluorine-containing elastomer as necessary, for example, fillers other than those mentioned above, processing aids, plasticizers, colorants, stabilizers, adhesion aids. Various additives such as release agents, conductivity imparting agents, thermal conductivity imparting agents, surface non-adhesives, flexibility imparting agents, heat resistance improvers, flame retardants, and the like, What is necessary is just to use a compounding agent in the range which does not impair the effect of this invention.

The fluorine-containing elastomer composition of the present invention can be prepared by mixing the above-described components using a normal elastomer processing machine, for example, an open roll, a Banbury mixer, a kneader or the like. In addition, it can be prepared by a method using a closed mixer or a method of co-coagulation from emulsion mixing.

The crosslinked product in the present invention can be obtained by crosslinking reaction of the fluorine-containing elastomer composition of the present invention. The crosslinking conditions may be appropriately set depending on the crosslinking method, the shape of the crosslinked product, etc., but are generally in the range of several seconds to 180 minutes at 100 to 200 ° C. Further, secondary crosslinking may be performed in order to stabilize the physical properties of the crosslinked product. The secondary crosslinking conditions are about 100 to 350 ° C. and about 30 minutes to 50 hours.

When peroxide crosslinking is performed, it can be performed under the crosslinking conditions of a normal crosslinkable fluorine-containing elastomer. For example, press crosslinking is performed by placing in a mold and holding at 120 to 200 ° C. for 1 to 60 minutes under pressure, followed by oven crosslinking by holding for 0 to 48 hours in an oven at 120 to 250 ° C. A crosslinked product can be obtained.

When oxazole crosslinking is carried out using a crosslinking agent such as bisaminophenol, it can be carried out under the crosslinking conditions of ordinary crosslinking elastomers. For example, press crosslinking is performed by placing in a mold and holding under pressure at 120 to 250 ° C. for 1 to 60 minutes, followed by oven crosslinking by holding in a 120 to 320 ° C. oven for 0 to 48 hours. When performed, a cross-linked product can be obtained. Further, bis (aminophenol) AF or the like may be added to a known crosslinkable elastomer crosslinking system, for example, a polyamine crosslinking system, a polyol crosslinking system, or a peroxide crosslinking system, to perform crosslinking in combination.

Further, imidazole crosslinking in which a carboxyl group is crosslinked with a bisdiaminophenyl-based crosslinking agent is optimal for a carboxyl-containing polymer having a carboxyl group other than the terminal, and has a relatively low crosslinking temperature (for example, 150 to 230 ° C., preferably 170 to 200). )) To give a crosslinked product having good physical properties.

The method for obtaining the preform from the composition may be a normal method, and may be performed by a known method such as a method of heat-compressing with a mold, a method of press-fitting into a heated mold, or a method of extruding with an extruder. it can. Alternatively, it may be dissolved in a solvent and molded by dip molding, coating or the like.
In the case of an extruded product such as a hose or an electric wire, the shape can be maintained even after extrusion, so that a preform that has been extruded without using a crosslinking agent can be used as it is. Of course, it is also possible to use a preform that has been heat-crosslinked with steam or the like using a crosslinking agent. In addition, when it is difficult to maintain the shape even after release in a non-crosslinked state in a molded product such as an O-ring, it can be carried out by using a preform that has been previously crosslinked using a crosslinking agent. .

You may comprise a laminated body by the base material which consists of the layer (crosslinked material layer) formed from the crosslinked material in this invention, and the at least 1 layer containing another material.
The “other material” may be selected appropriately depending on the required characteristics, intended use, etc., for example, metals such as iron, stainless steel, copper, aluminum and brass; glass plate Glass products such as woven fabrics and nonwoven fabrics of glass fibers; molded products and coverings of general-purpose resins and heat-resistant resins such as polypropylene, polyoxymethylene, polyimide, polyamideimide, polysulfone, polyethersulfone, polyetheretherketone; Molded articles and coverings of general-purpose rubbers such as SBR, butyl rubber, NBR and EPDM, and heat-resistant rubbers such as silicone rubber and fluorine rubber; woven fabrics and nonwoven fabrics of natural fibers and synthetic fibers can be used.

An intermediate layer may be formed of silicone rubber or the like in order to improve adhesion between the crosslinked product layer and the substrate. Moreover, you may further form the layer which has another effect | action as needed.

The production method of the laminate composed of the cross-linked product layer and the substrate is not particularly limited, and known methods such as co-extrusion, co-injection, and extrusion coating can also be used. It is preferably formed by applying an elastomer composition to a substrate. More specifically, it is preferably produced by a production method comprising a step of applying the composition to a substrate and a step of crosslinking the applied composition. As such a production method, for example, (1) after coating the composition on a peelable substrate, crosslinking is performed, and the obtained crosslinked product is peeled from the substrate, which is different from the substrate. A method of laminating (adhering) to another layer, and (2) a laminate comprising the cross-linked product and the base material, which is coated on the base material directly or via another layer and cross-linked. And the like.
As a method of applying the composition to a substrate, for example, a conventionally known method can be employed.

Moreover, you may interpose an adhesive bond layer between the layer formed from the crosslinked material in this invention, and a base material. By interposing the adhesive layer, the layer formed from the crosslinked product and the base material layer containing another material can be firmly joined and integrated. Examples of the adhesive used in the adhesive layer include acid anhydride-modified products of diene polymers; acid anhydride-modified products of polyolefins; polymer polyols (for example, glycol compounds such as ethylene glycol and propylene glycol, and adipic acid) Polyester polyol obtained by polycondensation of a dibasic acid, a partially saponified product of a copolymer of vinyl acetate and vinyl chloride, and a polyisocyanate compound (for example, a glycol compound such as 1,6-hexamethylene glycol) A reaction product of a molar ratio of 1 to 2 with a diisocyanate compound such as 2,4-tolylene diisocyanate; a molar ratio of a triol compound such as trimethylolpropane and a diisocyanate compound such as 2,4-tolylene diisocyanate of 1: 3 A mixture with a reaction product or the like) can be used.

Moreover, when producing the laminated body which has the layer and base material layer which are formed from the crosslinked material in this invention, you may surface-treat to the layer formed from the said crosslinked material as needed. The type of the surface treatment is not particularly limited as long as it is a treatment method that enables adhesion. For example, discharge treatment such as plasma discharge treatment or corona discharge treatment, wet metal sodium / naphthalene liquid treatment Etc. A primer treatment is also suitable as the surface treatment. Primer treatment can be performed according to a conventional method. When the primer treatment is performed, the surface of the layer formed from the cross-linked product that has not been surface-treated can be primed, but the cross-linked product that has been previously subjected to plasma discharge treatment, corona discharge treatment, metal sodium / naphthalene liquid treatment, etc. It is more effective if the surface of the layer formed from is further primed.

The cross-linked product obtained by cross-linking the fluorine-containing elastomer composition of the present invention is excellent in low fragrance, and thus can be suitably used for various applications. It is preferable to apply to a conveyance member. More specifically, the conveying member is a conveying member obtained by applying the fluorine-containing elastomer composition, and at least a part of the surface is made of a crosslinked product of the composition. Such a conveying member is also one aspect of the present invention.

In the present specification, the “conveying member” is not particularly limited as long as it is a member for conveying various articles. For example, in addition to a conveying roll, a conveying belt, a conveying hose, and the like, piping, etc. Including sealing materials such as packings and gaskets used.
Examples of articles to be conveyed include foods, cosmetics, pharmaceuticals, articles used for printing (for example, ink, pigment, paper, etc.).

The said conveyance member should just be that the surface of at least one part consists of a crosslinked material of the said composition. More specifically, a part or all of the surface in contact with the article to be conveyed may be made of a crosslinked product of the above composition.
For example, when the conveyance member is a conveyance roll, a part or all of the surface of the layer formed on the outermost periphery of the roll may be the above-mentioned crosslinked product. A part or all of the inner surface may be the above-mentioned crosslinked product.
Moreover, the said conveyance member may be comprised only by the crosslinked material of the said composition, and may be comprised by the laminated body containing a crosslinked material.

When the conveying member of the present invention is a conveying roll, the base material (core material) is preferably a metal such as iron, stainless steel, copper, aluminum, or brass, and more preferably aluminum. The cross-linked product may be formed so as to be in direct contact with the outer peripheral surface of the base material (core material), and is formed through another layer such as silicone rubber provided between the base material and the cross-linked product. Also good.

As a manufacturing method of the transport roll, (1) a method in which the fluorine-containing elastomer composition of the present invention is applied to the outer peripheral surface of the core material and crosslinked to form a cross-linked product layer, and (2) a core material by extrusion molding. (3) Forming the composition into a tube by extrusion molding after forming the composition into a layer on the outer peripheral surface of the substrate, and then cross-linking the core material through the tube, Examples thereof include a method of heating at 100 to 250 ° C. to closely adhere the tube to the core material surface.
Especially, it is preferable to manufacture by the method of said (1).

When the conveying member of the present invention is a conveying belt, a conveying hose, a sealing material, etc., it may be formed by a crosslinked product of the fluorine-containing elastomer composition of the present invention alone, depending on the required characteristics, You may form with the laminated body containing another layer. As the production method, the methods described above as the production method of the crosslinked product, such as a coating method, an extrusion molding method, a compression molding method, and an injection molding method, can be employed. Especially, it is preferable to manufacture by the apply | coating method.

Since the fluorine-containing elastomer composition of the present invention has the above-described configuration, the leakage of the hydrocarbon-based compound to the cross-linked product surface is extremely small, and the fragrance of the cross-linked product can be sufficiently suppressed.
Since the conveying member of the present invention has the above-described configuration, the transfer of the odorous component from the conveyed article to the conveying member and the odorous component from the conveying member to the article are sufficiently suppressed. It is possible to prevent deterioration of the quality of the conveyed article.

The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The measurement performed in each Example was performed by the following method.
(1) Hydrocarbon compound leakage amount Surface fluorine concentration and carbon concentration were measured using ESCA 3400 manufactured by Shimadzu Corporation as an X-ray photoelectron spectroscopy (ESCA) apparatus and using Mg as an X-ray source. When the polymer contained oxygen, the oxygen concentration was also measured. From this surface fluorine concentration and polymer composition, the theoretical carbon concentration that should exist on the surface was calculated and compared with the actual measured carbon concentration. When the polymer contains oxygen, the oxygen concentration was calculated and compared.
(2) Flavor test The test sample was immersed in fruit juice for 24 hours at room temperature and then washed with ion-exchanged water, and the degree of scent of the test sample was sensory evaluated. The test sample of Comparative Example 1 was evaluated in three stages with a strong fragrance as x, a fluororesin as ◯ with almost no fragrance, and a middle as Δ.

Example 1
Fluorine-containing elastomer comprising tetrafluoroethylene (TFE) / hexafluoropropylene (HFP) / vinylidene fluoride (VdF) containing iodine as a crosslinking group (FKM1: TFE / HFP / VdF = 20/30/50 (mol%)) ) 0.5 parts by weight of triallyl isocyanurate (TAIC, manufactured by Nippon Kasei Co., Ltd.) and 0.5 parts by weight of perhexa 25B (manufactured by NOF Corporation) per 100 parts by weight with an open roll Thus, a crosslinkable fluorine-containing elastomer composition (1) was obtained.

The obtained fluorine-containing elastomer composition (1) was subjected to press crosslinking at 160 ° C. for 10 minutes, and then oven-crosslinked in an air oven at 180 ° C. for 4 hours to obtain a crosslinked product (1). Got.

The obtained crosslinked product (1) was subjected to surface hydrocarbon compound leakage measurement and flavor test. The results are shown in Table 1.

Examples 2-3 and Comparative Examples 1-2
The crosslinked products (2) to (3) and the comparative crosslinked products (1) to (1) to (1) to (3) and the comparative crosslinked products (1) to (1), except that the components of the fluorine-containing elastomer composition and the blending amounts thereof were changed as shown in Table 1. 2) was obtained. The results of surface hydrocarbon compound leakage measurement and flavor test are shown in Table 1 (in Table 1, FFKM1: TFE / CF ₂ = CFO [CF ₂ CF (CF ₃ containing iodine as a crosslinking group) ) O] ₂ C ₃ F ₇ = 70/30 (mol%) fluorine-containing elastomer, FFKM2: tetrafluoro containing CNVE (CF ₂ = CFOCF ₂ CF (CF ₃ ) OCF ₂ CF ₂ CN) as a crosslinking group Fluorine-containing elastomer (TFE / PMVE = 60/40 (mol%)) composed of ethylene (TFE) / perfluoromethyl vinyl ether (PMVE), MT carbon black: MT carbon black (manufactured by CanCarb), AFTA-Ph: 2, 2-bis- [3-amino-4- (N-phenylamino) phenyl] hexafluoropropa ).

From the results of Examples 1 to 3 and Comparative Examples 1 and 2, the crosslinked products of Examples 1 to 3 in which the hydrocarbon compound does not substantially leak out are those of Comparative Examples 1 and 2 in which the amount of leakage of the hydrocarbon compound is large. It was found that it was excellent in low flavor compared with the cross-linked product. Therefore, it was confirmed that the technical significance exists in making a fluorine-containing elastomer composition into the structure of this invention.

Claims (2)

A fluorine-containing elastomer composition containing a crosslinkable fluorine-containing elastomer,
A fluorine-containing elastomer composition, wherein a hydrocarbon-based compound does not substantially leak onto the surface of the crosslinked product. A conveying member obtained by applying the fluorine-containing elastomer composition according to claim 1,
The conveying member is characterized in that at least a part of the surface is made of a crosslinked product of the composition.