JP2018009109A - Fluoro rubber cross-linked product and fluoro rubber composition - Google Patents

Abstract

Disclosed is a fluororubber crosslinked product having conductivity sufficient to prevent electrification to some extent and having appropriate flexibility. A cross-linked fluororubber obtained from a fluororubber composition containing a fluororubber and a polyol cross-linking agent, having a volume resistivity of 104 to 109 Ω · cm and a hardness of A60 to A90. Fluoro rubber cross-linked product. [Selection figure] None

Description

The present invention relates to a cross-linked fluororubber and a fluororubber composition.

A technique of adding carbon black to a composition containing a fluororubber and a polyol crosslinking agent for various purposes is known.

For example, Patent Document 1 discloses that carbon black can be used to balance the performance of the fluoropolymer composition, such as tensile stress, tensile strength, elongation, hardness, wear resistance, conductivity, and workability. Is described. Further, as suitable examples of carbon black, MT blacks (medium thermal black) having the product numbers of N-991, N-990, N-908, and N-907; FEF N-550; and furnace black having a large particle size Etc. are described.

Further, Patent Document 2 discloses the following (A) to (C) as a rubber composition for a fuel reforming system which is excellent in both characteristics of fossil fuel resistance and low extractability and excellent in extrusion processability. ) Is an essential component, and a rubber composition for a fuel reforming system is described.
(A) Fluoro rubber.
(B) Carbon black having a specific surface area of less than 28 m ² / g by the BET method.
(C) A non-sulfur crosslinking agent.

JP 2013-231116 A JP 2005-272786 A

Rubber rolls are used in the manufacture of paper and resin films. Since fluororubber has heat resistance, chemical resistance and flexibility, it has been studied to form a rubber roll with fluororubber. However, the fluororubber roll is charged due to friction and peeling, and a disadvantage that the paper or film is adsorbed and wound around the roll to reduce productivity is expected. Further, it has been studied to manufacture a conductive fluoro rubber roll due to dust adhesion, but other disadvantages such as current leakage are expected.

Then, an object of this invention is to provide the fluororubber crosslinked material which has electroconductivity which can prevent an electric charge to some extent, and has moderate softness | flexibility.

Another object of the present invention is to provide a fluororubber composition capable of producing a fluororubber cross-linked product having conductivity sufficient to prevent electrification to some extent and having appropriate flexibility.

The present invention is a fluororubber crosslinked product obtained from a fluororubber composition containing fluororubber and a polyol crosslinking agent, having a volume resistivity of 10 ⁴ to 10 ⁹ Ω · cm and a hardness of A60 to A90. This is a cross-linked fluororubber product.
The fluororubber composition further comprises at least one additive selected from the group consisting of carbon black having a nitrogen adsorption specific surface area of 60 m ² / g or more, and a wax, a processing aid, a plasticizer, and a softening agent. It is preferable to include.

The present invention also provides at least one additive selected from the group consisting of fluororubber, polyol crosslinking agent, carbon black having a nitrogen adsorption specific surface area of 60 m ² / g or more, and a processing aid, a plasticizer and a softening agent. It is also a fluororubber composition characterized by containing an agent.
The present invention is also a fluororubber crosslinked product obtained from the above-described fluororubber composition.

The cross-linked fluororubber of the present invention has conductivity that can prevent charging to some extent and has moderate flexibility.

Another object of the present invention is to provide a fluororubber composition capable of producing a fluororubber cross-linked product having conductivity sufficient to prevent electrification to some extent and having appropriate flexibility.

Hereinafter, the present invention will be specifically described.

One feature of the cross-linked fluororubber of the present invention is that the volume resistivity is 10 ⁴ to 10 ⁹ Ω · cm. The volume resistivity is preferably 10 ⁵ Ω · cm or more, and preferably 10 ⁸ Ω · cm or less.

The volume specific resistance is measured with a sheet having a thickness of 2 mm at room temperature using JIS K6271, double ring electrode method.

One feature of the cross-linked fluororubber of the present invention is that the hardness is A60 to A90. The hardness is preferably A65 or more, and preferably A80 or less.
Addition of a conductive substance is unavoidable when imparting conductivity to a cross-linked fluororubber that is insulative, but flexibility is impaired when a conductive substance is added. Although the fluororubber crosslinked product of the present invention has a volume resistivity within the above-described range, it has moderate flexibility.

The hardness is measured with a type A durometer according to JIS K6253.

The cross-linked fluororubber of the present invention is obtained from a fluororubber composition containing a fluororubber and a polyol cross-linking agent. The cross-linked fluororubber of the present invention includes a fluoro rubber cross-linked by polyol cross-linking, but has a conductivity that can prevent charging to some extent and has an appropriate flexibility.

The cross-linked fluororubber is preferably obtained by cross-linking a fluororubber composition containing a fluororubber and a polyol cross-linking agent. The fluororubber composition containing a fluororubber and a polyol cross-linking agent is preferably subjected to primary cross-linking and secondary cross-linking. More preferably, it is obtained by subsequent crosslinking. Secondary crosslinking may be omitted depending on the use of the fluororubber crosslinked product, etc., but it can be expected to have effects such as completion of crosslinking, decomposition of excess crosslinking agent, diffusion of gas generated during crosslinking, removal of residual strain, etc. Thereby, various characteristics improve compared with the crosslinked material after primary crosslinking. On the other hand, when secondary crosslinking is carried out, the volume resistivity is usually increased as compared with the crosslinked product after primary crosslinking, but it is possible to suppress an increase in volume resistivity when a specific condition is satisfied, Found by the inventors.

The crosslinking can be performed at 130 to 300 ° C. for 1 to 30 hours.
The primary crosslinking is desirably performed at 130 to 200 ° C. for 1 to 60 minutes, and the secondary crosslinking is desirably performed at 150 to 300 ° C. for 30 minutes to 30 hours.
Even if the said fluororubber crosslinked material is obtained by carrying out secondary crosslinking, it has the volume specific resistance mentioned above.

The fluororubber is a polyol-crosslinkable fluororubber. As the fluororubber, a fluororubber containing a vinylidene fluoride (VdF) unit is preferable. The fluororubber usually comprises an amorphous polymer having fluorine atoms bonded to carbon atoms constituting the main chain and having rubber elasticity.

The fluororubber is preferably a fluororubber having a fluorine content of 64% by mass or more, and more preferably a fluororubber having a fluorine content of 66% by mass or more from the viewpoint of heat resistance, chemical resistance, flexibility, and the like. preferable. The upper limit of the fluorine content is not particularly limited, but is preferably 74% by mass or less. The fluorine content can be determined by calculation from the polymer composition.

The fluororubber is preferably a copolymer containing a VdF unit and a copolymer unit derived from another comonomer.
In the fluororubber, the content of VdF units is preferably 20 mol% or more, more preferably 45 mol% or more, more preferably 55 mol%, based on the total number of moles of VdF units and polymerization units derived from other comonomers. % Or more is more preferable. The content of VdF units is preferably 85 mol% or less, more preferably 80 mol% or less, based on the total number of moles of VdF units and polymerized units derived from other comonomers.

The fluororubber has a content of polymerized units derived from other comonomer of 15 mol% or more based on the total number of moles of VdF units and polymerized units derived from other comonomer. Preferably, 20 mol% or more is more preferable. The content of polymerized units derived from other comonomers is also preferably 80 mol% or less, preferably 55 mol% or less, based on the total number of moles of VdF units and polymerized units derived from other comonomers. More preferred is 45 mol% or less.

The other comonomer is not particularly limited as long as it is copolymerizable with VdF. For example, tetrafluoroethylene [TFE], hexafluoropropylene [HFP], perfluoro (alkyl vinyl ether) [PAVE], chloro Trifluoroethylene [CTFE], trifluoroethylene, trifluoropropylene, tetrafluoropropylene, pentafluoropropylene, trifluorobutene, tetrafluoroisobutene, hexafluoroisobutene, vinyl fluoride, general formula (1):
CH ₂ = CFRf ¹ (1)
(Wherein Rf ¹ is a linear or branched fluoroalkyl group having 1 to 12 carbon atoms) fluorinated monomer such as fluorinated ethylenic monomer (1); ethylene [Et ], Non-fluorine-containing monomers such as propylene [Pr] and alkyl vinyl ether, etc., and one or more of these monomers and compounds can be used in combination.
Examples of the PAVE include perfluoro (methyl vinyl ether) [PMVE], perfluoro (ethyl vinyl ether) [PEVE], perfluoro (propyl vinyl ether) [PPVE], and the like.
The fluorine-containing ethylenic monomer (1) has the following general formula:
CH ₂ = CF (CF ₂ ) _m F
(Wherein, m is an integer of 1 to 7). The m is more preferably an integer of 1 to 5, and further preferably an integer of 1 to 3.
As the fluorine-containing ethylenic monomer _{(1), CH 2 = CFCF} 3, CH 2 = CFCF 2 CF 3, CH 2 = CFCF 2 CF 2 CF 3, CH 2 = CFCF 2 CF 2 CF 2 CF 3 , etc. Among them, 2,3,3,3-tetrafluoropropene represented by CH ₂ ═CFCF ₃ is preferable.

The fluororubber is preferably a copolymer containing copolymer units derived from VdF units and fluorine-containing monomers (excluding VdF). The fluororubber preferably further contains a copolymer unit derived from a monomer copolymerizable with VdF and the fluorine-containing monomer.

Examples of the fluororubber include VdF / HFP copolymer, VdF / TFE / HFP copolymer, VdF / CTFE copolymer, VdF / CTFE / TFE copolymer, VdF / PFE copolymer, VdF / TFE / PAVE. Copolymer, VdF / HFP / PAVE copolymer, VdF / HFP / TFE / PAVE copolymer, VdF / TFE / Pr copolymer, VdF / Et / HFP copolymer, VdF / Fluorine-containing ethylenic monomer (1) Copolymer, VdF / HFP / Fluorine-containing ethylenic monomer (1) Copolymer, VdF / TFE / Fluorine-containing ethylenic monomer (1) Copolymer, VdF / HFP / TFE / Fluorinated ethylenic monomer (1) copolymer, VdF / PAVE / fluorinated ethylenic monomer (1) copolymer, VdF / TFE / PAVE / fluorinated ethylenic monomer (1) Copolymer, VdF / HFP / PAVE / Fluorine-containing ethylenic monomer (1) Copolymer, and VdF / HFP / TFE / PAVE / Fluorine-containing ethylenic monomer (1) Copolymer Etc.
Among these, from the viewpoint of heat resistance, chemical resistance, flexibility, etc., VdF / HFP copolymer, VdF / TFE / HFP copolymer, VdF / PAVE copolymer, VdF / TFE / PAVE copolymer, At least one selected from the group consisting of a VdF / HFP / PAVE copolymer and a VdF / HFP / TFE / PAVE copolymer is preferred.

The VdF / HFP copolymer preferably has a VdF / HFP composition of (45 to 85) / (55 to 15) (mol%), more preferably (50 to 80) / (50 to 20). ) (Mol%), and more preferably (60-80) / (40-20) (mol%).

In the VdF / TFE / HFP copolymer, the composition of VdF / TFE / HFP is preferably (30 to 80) / (4 to 35) / (10 to 35) (mol%). 80) / (5-20) / (15-35) (mol%) is more preferable.

As said VdF / PAVE copolymer, it is preferable that the composition of VdF / PAVE is (65-90) / (35-10) (mol%).

As said VdF / TFE / PAVE copolymer, it is preferable that the composition of VdF / TFE / PAVE is (40-80) / (3-40) / (15-35) (mol%).

As said VdF / HFP / PAVE copolymer, it is preferable that the composition of VdF / HFP / PAVE is (65-90) / (3-25) / (3-25) (mol%).

As said VdF / HFP / TFE / PAVE copolymer, the composition of VdF / HFP / TFE / PAVE is (40-90) / (0-25) / (0-40) / (3-35) (mol) %), And (40-80) / (3-25) / (3-40) / (3-25) (mol%) is more preferable.

In the VdF / fluorinated ethylenic monomer (1) copolymer, VdF / fluorinated ethylenic monomer (1) is (45 to 85) / (55 to 15) (mol%). Is preferable, and (50-80) / (50-20) (mol%) is more preferable.

The VdF / HFP / fluorinated ethylenic monomer (1) copolymer has a VdF / HFP / fluorinated ethylenic monomer (1) of (40-80) / (5-35) / (10 It is preferable that it is -35) (mol%), and it is more preferable that it is (40-80) / (10-35) / (10-35) (mol%).

The VdF / TFE / fluorinated ethylenic monomer (1) copolymer has a VdF / TFE / fluorinated ethylenic monomer (1) of (40-80) / (3-30) / (10 ~ 40) (mol%).

The VdF / HFP / TFE / fluorinated ethylenic monomer (1) copolymer has a VdF / HFP / TFE / fluorinated ethylenic monomer (1) of (40-80) / (5-40 ) / (3-30) / (5-40) (mol%).

The VdF / PAVE / fluorinated ethylenic monomer (1) copolymer has a VdF / PAVE / fluorinated ethylenic monomer (1) of (65 to 90) / (5 to 35) / (5 ~ 35) (mol%).

The VdF / TFE / PAVE / fluorinated ethylenic monomer (1) copolymer has a VdF / TFE / PAVE / fluorinated ethylenic monomer (1) of (40-80) / (3-30. ) / (5-40) / (5-40) (mol%).

The VdF / HFP / PAVE / fluorinated ethylenic monomer (1) copolymer has a VdF / HFP / PAVE / fluorinated ethylenic monomer (1) of (65 to 90) / (3 to 25 ) / (3-25) / (3-25) (mol%).

The above VdF / HFP / TFE / PAVE / fluorinated ethylenic monomer (1) copolymer has a VdF / HFP / TFE / PAVE / fluorinated ethylenic monomer (1) of (40 to 90) / It is preferably (0-25) / (0-40) / (0-40) / (3-35) (mol%), (40-80) / (3-25) / (3-40) / (3-25) / (3-25) (mol%) is more preferable.

From the viewpoint of heat resistance, chemical resistance, flexibility, etc., the fluororubber is more preferably at least one selected from the group consisting of a VdF / HFP copolymer and a VdF / TFE / HFP copolymer.
As said fluororubber, what was demonstrated above is not restricted to 1 type, You may use 2 or more types.

The polyol crosslinking agent is preferably a polyhydroxy compound from the viewpoint that the compression set of the fluororubber after crosslinking is small and excellent in heat resistance and moldability, and in particular, polyhydroxy aromatic from the point of excellent heat resistance. Compounds are preferred. The polyhydroxy aromatic compound is not particularly limited, and for example, 2,2-bis (4-hydroxyphenyl) propane (hereinafter referred to as bisphenol A), 2,2-bis (4-hydroxyphenyl) hexafluoropropane [ 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) tetrafluor Dichloropropane, 4,4′-dihydroxydiphenyl sulfone, 4,4′-dihydroxydiphenyl ketone, tri (4-hydroxyphenyl) methane, 3,3 ′, 5,5′-tetrachlorobisphenol A, 3,3 ′, 5,5′-tetrabromobisphenol A and the like can be mentioned. 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.

The polyol crosslinking agent is particularly preferably 2,2-bis (4-hydroxyphenyl) hexafluoropropane [bisphenol AF].

In the fluororubber composition, the content of the polyol crosslinking agent is preferably 0.2 to 10 parts by mass, and preferably 0.5 to 6 parts by mass with respect to 100 parts by mass of the fluororubber. More preferably, it is 0.7-3 mass parts. When the content is too small, the crosslinking density tends to be low and the compression set tends to be large. When the content is too large, the crosslink density becomes too high, so that there is a tendency to be easily broken during compression.

The fluororubber composition preferably further contains carbon black from the viewpoint of appropriate electrical conductivity and appropriate flexibility, and includes carbon black having a nitrogen adsorption specific surface area (N ₂ SA) of 60 m ² / g or more. It is more preferable. The nitrogen adsorption specific surface area _(N 2 SA) is more preferably not less than ^{70m 2 / g, 80m 2 /} g or more, and particularly preferably at least ^90m 2 / g, and most preferably at least 100 m ² / g, the upper limit Although not particularly limited, it may be 160 m ² / g. The nitrogen adsorption specific surface area (N ₂ SA) can be measured by the method described in JIS K6217-2: 2001.

The carbon black may have a dibutyl phthalate (DBP) oil absorption of 40 to 180 ml / 100 g or 60 to 160 ml / 100 g. The dibutyl phthalate (DBP) oil absorption can be measured by the method described in JIS K6217-4: 2008.

Examples of the carbon black include furnace black, acetylene black, thermal black, channel black, graphite, etc. due to differences in manufacturing methods, and carbon black for rubber, carbon black for color, and conductive carbon black due to differences in applications. Examples include all commercially available carbon blacks. Of these, furnace black is preferred as the carbon black.

Examples of the carbon black include 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), IISAF-HS (N ₂ SA: 99 m ² / g, DBP: 129 ml / 100 g), N339 (N ₂ SA: 93 m ² / g, DBP: 119 ml / 100 g), N339 (N ₂ SA: 93 m ² / g, DBP ^{_{: 119ml / 100g), HAF-}} HS (N 2 SA: 82m 2 / g, DBP: 126ml / 1 ^{_{0g), N351 (N 2 SA}} : 74m 2 / g, DBP: 127ml / 100g), HAF (N 2 SA: 79m 2 / g, DBP: 101ml / 100g), LI-HAF (N 2 SA: 74m 2 / g, DBP: 101 ml / 100 g), HAF-LS (N ₂ SA: 84 m ² / g, DBP: 75 ml / 100 g) and the like. These carbon blacks may be used alone or in combination of two or more.

In the fluororubber composition, the blending amount of carbon black is preferably 5 to 30 parts by mass, more preferably 7 parts by mass or more, still more preferably 10 parts by mass or more, and 25 parts by mass or less with respect to 100 parts by mass of the fluororubber. Is more preferable, and 20 mass parts or less is still more preferable. If the amount of carbon black is excessive, the hardness of the cross-linked fluororubber product tends to increase. If the amount is too small, the volume resistivity of the cross-linked fluororubber product tends to increase.

The fluororubber composition may further contain at least one additive selected from the group consisting of a wax, a processing aid, a plasticizer, and a softening agent, from the viewpoint of moderate conductivity and moderate flexibility. preferable.

Examples of the wax include natural wax, synthetic wax, and processed / modified wax.
Examples of the natural wax include waxes derived from animals such as shellac wax; waxes derived from plants such as carnauba wax, ceresin wax, candelilla wax and rice wax; petroleum waxes such as petroleum jelly and microcrystalline wax; montan wax, ozokerite and the like Examples include mineral-derived waxes.
Examples of the synthetic wax include polypropylene wax and Fischer-Tropsch wax, higher fatty acid esters such as ethyl oleate and stearyl stearate, fatty acid amides such as oleic amide, ketones and amines, hydrogenated oil, and the like.
Examples of the processed / modified wax include those processed or modified by chemical / physical means using the wax as a raw material, such as an oxidized wax obtained by oxidizing a raw material wax with chemicals or oxygen in the air.

Examples of the processing aid include higher fatty acids such as stearic acid, oleic acid, palmitic acid and lauric acid; higher fatty acid salts such as sodium stearate and zinc stearate; aliphatic alcohols; polyglycols such as ethylene glycol, glycerin and diethylene glycol Aliphatic amines such as stearylamine, silicone oils, silicone polymers, low molecular weight polyethylene, phosphate esters, rosin, (halogenated) dialkylamines, surfactants, sulfone compounds, fluorine-based auxiliary agents, organic amine compounds Etc. can be exemplified.

Examples of the plasticizer include phthalic acid derivatives, phosphoric acid derivatives, sebacic acid derivatives, pentaerythritol, low molecular weight fluororubber, and more specifically, dialkyl phthalates, dialkyl sebacates, pentaerythritol, and the like.

Examples of the softening agent include lubricating oil, process oil, coal tar, castor oil, calcium stearate and the like.

The additive is preferably at least one selected from the group consisting of waxes, aliphatic amines, phthalic acid derivatives, and sebacic acid derivatives from the viewpoint of moderate conductivity and moderate flexibility. And at least one selected from the group consisting of waxes, higher fatty acid esters and dialkyl sebacates is more preferred.

A fluororubber composition containing the fluororubber, the polyol crosslinking agent, the carbon black and the additive is also one aspect of the present invention. That is, the present invention provides at least one additive selected from the group consisting of fluororubber, polyol crosslinking agent, carbon black having a nitrogen adsorption specific surface area of 60 m ² / g or more, and a processing aid, a plasticizer, and a softening agent. It is also a fluororubber composition characterized by containing an agent.

The present invention is also a cross-linked fluororubber obtained from the fluororubber composition of the present invention. A cross-linked fluororubber can be obtained by cross-linking the fluororubber composition of the present invention. It is preferable to obtain a crosslinked fluororubber by subjecting the fluororubber composition of the present invention to primary crosslinking and secondary crosslinking. Secondary crosslinking may be omitted depending on the use of the fluororubber crosslinked product, etc., but it can be expected to have effects such as completion of crosslinking, decomposition of excess crosslinking agent, diffusion of gas generated during crosslinking, removal of residual strain, etc. Thereby, various characteristics improve compared with the crosslinked material after primary crosslinking. On the other hand, when the secondary cross-linking is performed, the volume resistivity is usually increased as compared with the cross-linked product after the primary cross-linking. However, when the fluororubber composition contains the carbon black and the additive, the volume specific resistance is increased. It has been found by the present inventors that the resistance decreases moderately.

The crosslinking can be performed at 130 to 300 ° C. for 1 to 30 hours.
The primary crosslinking can be performed at 130 to 200 ° C. for 1 to 60 minutes, and the secondary crosslinking can be performed at 150 to 300 ° C. for 30 minutes to 30 hours. The primary crosslinking may be performed at 2 to 15 MPa.
Even if the said fluororubber crosslinked material is obtained by carrying out secondary crosslinking, it has the volume specific resistance mentioned above.

The crosslinking method is not particularly limited, and steam crosslinking using a steam vulcanizing can and normal heat compression molding using a heat press machine can be adopted, and among them, a crosslinking reaction by heat compression molding is preferable.

Prior to the steam crosslinking, the fluororubber composition may be molded. Examples of the molding method include, but are not limited to, a pressure molding method using a mold and the like, and an extrusion molding method using an extruder.

Next, the said fluororubber composition for forming the fluororubber crosslinked material of this invention and the arbitrary components which the fluororubber composition of this invention can contain are demonstrated.

The fluororubber composition preferably further contains a crosslinking accelerator. The crosslinking accelerator promotes the formation of an intramolecular double bond in the dehydrofluorination reaction of the polymer main chain and the addition of a polyhydroxy compound to the generated double bond.

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

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 viewpoints of crosslinkability, mechanical properties, and flexibility.

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. -2-methoxypropylphosphonium chloride, benzylphenyl (dimethylamino) phosphonium chloride, and the like. Among these, benzyltriphenylphosphonium chloride (BTPPC) is preferable in terms of crosslinkability, mechanical properties, and flexibility. preferable.

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

It is preferable that the compounding quantity of the said crosslinking accelerator is 0.01-8 mass parts with respect to 100 mass parts of fluororubber, More preferably, it is 0.02-5 mass parts. If the amount of the crosslinking accelerator is too small, the crosslinking of the fluororubber does not proceed sufficiently, and the heat resistance and the like of the resulting crosslinked product may be lowered. When there are too many said crosslinking accelerators, there exists a possibility that the moldability of the said fluororubber composition may fall, the elongation in a mechanical physical property will fall, and a softness | flexibility will also fall.

The fluororubber composition preferably further contains an acid acceptor. Examples of the acid acceptor include magnesium oxide, calcium oxide, lead oxide, hydrotalcite and the like. The acid acceptor is also preferably used in combination with the crosslinking accelerator.

The fluororubber composition preferably further contains a crosslinking aid such as calcium hydroxide. The crosslinking aid is also preferably used in combination with the crosslinking accelerator.

The fluororubber composition may further contain a filler, a release agent, a pigment, a lubricant, an antioxidant, a foaming agent, a fragrance, an oil, a softening agent, and the like as long as the effect of the present invention is not affected. Good.

The fluororubber composition can be obtained by kneading each component. For the kneading, an open roll, a Banbury mixer, a pressure kneader, an extruder, or the like can be used, but it is preferable to use an open roll or a pressure kneader from the viewpoint that it can be uniformly dispersed.

The cross-linked fluororubber of the present invention and the cross-linked fluororubber obtained from the fluororubber composition of the present invention can be suitably used for the following applications.

(1) When static electricity is generated in a rubber roll used for manufacturing rubber roll paper or film, the paper or the film may wrap around the rubber roll, or dust or dirt may adhere to the product to contaminate the product. . Further, in the process of painting or printing, unevenness of painting or printing may occur. Also, sparks due to static electricity can cause a fire and must be avoided. Since the said fluororubber crosslinked material has moderate electroconductivity and moderate softness | flexibility, these subjects can be solved. Therefore, the said fluororubber crosslinked material can be used suitably as a rubber roll, and can be suitably used especially as a rubber roll used in order to manufacture paper and a film.

(2) In assembly lines such as rubber sheet electronic devices, since static electricity adversely affects products, countermeasures against static electricity such as work tables, shelves and floors are required. The fluororubber crosslinked product can be suitably used as a rubber sheet for static elimination because it has moderate conductivity and moderate flexibility.

(3) Tubes and hoses for transporting rubber tubes and rubber hose polymer powders and pellets by pressure, when the inner surface is charged, the powders and pellets adhere or are blocked by the adhered powders and pellets. Sometimes. In addition, sparks due to static electricity can cause fires and explosions and should be avoided. Since the fluororubber crosslinked product has appropriate conductivity and moderate flexibility, it can be suitably used as a rubber tube or rubber hose, and particularly suitable as a rubber tube or rubber hose for pumping or vacuum transportation. It is.
Also, when transporting flammable liquids, static sparks must be avoided because they can cause fires and explosions. Since the fluororubber crosslinked product has moderate conductivity and moderate flexibility, it can also be suitably used as a tube or hose for transporting flammable liquids.

(4) Sealing material When static electricity is generated in the semiconductor manufacturing apparatus, the device is damaged or foreign matter is adsorbed to the device. Since the fluororubber crosslinked product has appropriate conductivity and moderate flexibility, it can be suitably used as a sealing material, and in particular, can be suitably used as a sealing material used in a semiconductor manufacturing apparatus.

(5) Others Since the above-mentioned crosslinked fluororubber has appropriate conductivity and moderate flexibility, it can be suitably used as an electromagnetic wave shield.

Although the use which can use the said fluororubber crosslinked material suitably was demonstrated, naturally the said fluororubber crosslinked material can also be used for the following use. The fluororubber crosslinked product may be laminated with another material to obtain a laminate.

Sealing material:
In semiconductor-related fields such as semiconductor manufacturing equipment, liquid crystal panel manufacturing equipment, plasma panel manufacturing equipment, plasma address liquid crystal panels, field emission display panels, solar cell substrates, etc., O (square) -rings, packings, gaskets, diaphragms, and other various types Examples thereof include a sealing material, and these can be used for a CVD apparatus, a dry etching apparatus, a wet etching apparatus, an oxidation diffusion apparatus, a sputtering apparatus, an ashing apparatus, a cleaning apparatus, an ion implantation apparatus, and an exhaust apparatus. Specifically, O-rings for gate valves, quartz-window O-rings, chamber O-rings, gate O-rings, bell jar O-rings, coupling O-rings, pump O-rings, It can be used as a diaphragm, an O-ring of a semiconductor gas control device, a resist developer, an O-ring for a stripping solution, and other various sealing materials.

In the automobile field, it can be used for gaskets, shaft seals, valve stem seals, various sealing materials used for engines and peripheral devices, and various sealing materials for AT devices. Examples of the sealing material used for the fuel system and peripheral devices include O (square) -rings, packings, diaphragms, and the like. Specifically, engine head gasket, metal gasket, oil pan gasket, crankshaft seal, camshaft seal, valve stem seal, manifold packing, oxygen sensor seal, injector O-ring, injector packing, fuel pump O-ring, Diaphragm, crankshaft seal, gearbox seal, power piston seal, cylinder liner seal, valve stem seal, automatic transmission front pump seal, rear axle pinion seal, universal joint gasket, speedometer pinion seal, foot brake Piston cup, torque transmission O-ring, oil seal, exhaust gas reburner seal, bearing seal, carburetor sensor die It can be used as Fulham like.

In the aircraft field, the rocket field, and the marine field, there are diaphragms, O (square) -rings, valves, packings, various sealing materials, and the like, which can be used for fuel systems. Specifically, in the aircraft field, it is used for jet engine valve stem seals, gaskets and O-rings, rotating shaft seals, hydraulic equipment gaskets, firewall seals, etc., and in the ship field, screw propeller shaft stern seals, Used for intake and exhaust valve stem seals of diesel engines, valve seals of butterfly valves, shaft seals of butterfly valves, and the like.

In the field of chemical plants, valves, packings, diaphragms, O (square) -rings, various sealing materials, and the like can be used, and these can be used in the manufacturing process of chemical products such as pharmaceuticals, agricultural chemicals, paints, and resins. Specifically, chemical pumps, rheometers, pipe seals, heat exchanger seals, glass cooler packing for sulfuric acid production equipment, pesticide sprayers, pesticide transfer pump seals, gas pipe seals, plating solutions Seals, packing for high-temperature vacuum dryers, roller seals for papermaking belts, fuel cell seals, wind tunnel joint seals, gas chromatography, packing for pH meter tube connections, analytical instruments, physics and chemistry instrument seals, diaphragms, valve parts Etc. can be used.

In the field of photography such as a developing machine, the field of printing such as a printing machine, and the field of painting such as a painting facility, it can be used as a seal or valve part of a dry copying machine.
Moreover, it can use for the various rolls of the said field | area.

In the field of food plant equipment, valves, packings, diaphragms, O (square) -rings, various sealing materials, and the like can be mentioned, which can be used in food manufacturing processes. Specifically, it can be used as a seal for a plate heat exchanger, a solenoid valve seal for a vending machine, or the like.

In the field of nuclear plant equipment, packing, O-rings, diaphragms, valves, various sealing materials, and the like can be given.

In the general industrial field, packing, O-rings, diaphragms, valves, various sealing materials and the like can be mentioned. Specifically, hydraulic, lubrication machinery seals, bearing seals, dry cleaning equipment windows, other seals, uranium hexafluoride concentrator seals, cyclotron seals (vacuum) valves, automatic packaging machine seals, air Used for diaphragms (pollution measuring devices) of sulfur dioxide and chlorine gas analysis pumps.

In the fuel cell field, specifically, it is used as a sealing material between electrodes and separators, a seal for hydrogen / oxygen / product water piping, and the like.

In the field of electronic components, specifically, it is used as a heat radiating material, an electromagnetic shielding material, a hard disk drive gasket of a computer, and the like.

There are no particular limitations on what can be used for on-site molding, and examples include an engine oil pan gasket, a magnetic recording device gasket, and a clean room filter unit sealing agent.

Sliding member:
In automobile-related fields, piston rings, shaft seals, valve stem seals, crankshaft seals, camshaft seals, oil seals and the like can be mentioned.
In general, a fluororubber product used for a portion that slides in contact with another material is exemplified.

Non-adhesive material:
For example, hard disk crash stopper in the computer field.

Fields that utilize water and oil repellency:
Examples include automobile wiper blades and outdoor tent pulling cloths.

Next, the present invention will be described with reference to examples, but the present invention is not limited to such examples.

Each numerical value of the examples was measured by the following method.

Using a sheet having a volume resistivity of 2 mm, measurement was performed at room temperature using the double ring electrode method of JIS K6271.

Three sheets with a thickness of 2 mm were stacked and measured using a type A durometer according to JIS K6253.

Examples 1-8, Comparative Example 1
Each component was mix | blended according to prescription of Table 1, and it knead | mixed on the open roll, and prepared the fluororubber composition. Next, the fluororubber composition is crosslinked by primary crosslinking (press crosslinking) at 160 ° C. for 30 minutes and secondary crosslinking (oven crosslinking) at 230 ° C. for 22 hours to obtain a crosslinked fluororubber (about 120 mm × 150 mm × thickness 2 mm sheet).

The detail of each component described in Table 1 is shown below.
Fluoro rubber: Vinylidene fluoride / hexafluoropropylene copolymer (fluorine content 66 mass%)
Bisphenol AF
Crosslinking accelerator: DBU-B
Carbon black 1: SRF carbon, nitrogen adsorption specific surface area 27 m ² / g, DBP oil absorption 68 ml / 100 g
Carbon black 2: HAF carbon, nitrogen adsorption specific surface area 79 m ² / g, DBP oil absorption 101 ml / 100 g
Carbon black 3: ISAF carbon, nitrogen adsorption specific surface area of 119 m ² / g, DBP oil absorption of 114 ml / 100 g
Magnesium oxide: Kyowa Mug 150 manufactured by Kyowa Chemical Industry Co., Ltd.
Calcium hydroxide: Calm 2000 made by Omi Chemical Co., Ltd.
Carnauba wax: Carnauba wax No. 1 stearyl stearate: reagent stearylamine: Farmin 86V manufactured by Kao Corporation

Table 1 shows the volume resistivity and hardness of the obtained fluororubber crosslinked product.

Claims (4)

A cross-linked fluororubber obtained from a fluororubber composition containing a fluororubber and a polyol cross-linking agent, wherein the volume resistivity is 10 ⁴ to 10 ⁹ Ω · cm, and the hardness is A60 to A90. Fluoro rubber cross-linked product. The fluororubber composition further includes at least one additive selected from the group consisting of carbon black having a nitrogen adsorption specific surface area of 60 m ² / g or more, and a wax, a processing aid, a plasticizer, and a softening agent. The fluororubber cross-linked product according to claim 1 comprising. Fluorine rubber, polyol cross-linking agent, carbon black having a nitrogen adsorption specific surface area of 60 m ² / g or more, and at least one additive selected from the group consisting of wax, processing aid, plasticizer and softener A fluororubber composition characterized by the above. A cross-linked fluororubber obtained from the fluororubber composition according to claim 3.