WO2020066770A1 - Composition de caoutchouc nitrile et procédé de production de composition de caoutchouc nitrile - Google Patents

Composition de caoutchouc nitrile et procédé de production de composition de caoutchouc nitrile Download PDF

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Publication number
WO2020066770A1
WO2020066770A1 PCT/JP2019/036482 JP2019036482W WO2020066770A1 WO 2020066770 A1 WO2020066770 A1 WO 2020066770A1 JP 2019036482 W JP2019036482 W JP 2019036482W WO 2020066770 A1 WO2020066770 A1 WO 2020066770A1
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rubber composition
nitrile
nitrile rubber
weight
plasticizer
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PCT/JP2019/036482
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English (en)
Japanese (ja)
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義雄 福峯
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日本ゼオン株式会社
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Priority to JP2020548534A priority Critical patent/JP7331857B2/ja
Publication of WO2020066770A1 publication Critical patent/WO2020066770A1/fr

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/20—Compounding polymers with additives, e.g. colouring
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00—Use of organic ingredients
    • C08K5/04—Oxygen-containing compounds
    • C08K5/10—Esters; Ether-esters
    • C08K5/101—Esters; Ether-esters of monocarboxylic acids
    • C08K5/103—Esters; Ether-esters of monocarboxylic acids with polyalcohols
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L27/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Compositions of derivatives of such polymers
    • C08L27/02—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C08L27/04—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen; Compositions of derivatives of such polymers not modified by chemical after-treatment containing chlorine atoms
    • C08L27/06—Homopolymers or copolymers of vinyl chloride
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
    • C08L67/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L9/00—Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
    • C08L9/02—Copolymers with acrylonitrile

Definitions

  • the present invention provides a nitrile rubber composition which is excellent in processability, and can provide a rubber crosslinked product having excellent compression set resistance, compression stress retention and cold resistance, and a nitrile rubber composition such as this.
  • the present invention relates to a crosslinkable nitrile rubber composition and a crosslinked rubber obtained by using the composition.
  • the invention also relates to a method for producing such a nitrile rubber composition.
  • rubbers containing an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit and a conjugated diene monomer unit are known as rubbers having excellent fuel oil resistance. It is mainly used as a material for rubber products around various oils of automobiles such as fuel hoses, gaskets, packings, oil seals and the like.
  • nitrile group-containing copolymer is required. It is effective to increase the amount of the nitrile group-containing monomer in the combined rubber and to hydrogenate the nitrile group-containing copolymer rubber. However, when the amount of the nitrile group-containing monomer in the nitrile group-containing copolymer rubber is increased or when hydrogenated, it becomes hard when blended with a vinyl chloride resin, resulting in reduced workability. was there.
  • ⁇ , ⁇ -ethylenically unsaturated nitrile monomer units were used as a nitrile group-containing copolymer rubber in order to further improve fuel oil resistance and heat resistance.
  • a rubber crosslinked product obtained by using such a rubber composition has a compression set resistance, a compression stress
  • the inventors have found that they have excellent retention and cold resistance, and have completed the present invention.
  • a nitrile group-containing copolymer rubber (A) containing ⁇ , ⁇ -ethylenically unsaturated nitrile monomer units at a ratio of 40 to 50% by weight and an iodine value of 5 to 50 is used.
  • a plasticizer (C) having a molecular weight of 500 to 2,000.
  • the plasticizer (C) is preferably a polyetherester (c1) represented by the following general formula (1).
  • R 1 is each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms
  • R 2 is each independently a hydrogen atom or a 1 to 6 carbon atom.
  • n is an integer of 1 to 40.
  • the plasticizer (C) is preferably an adipic acid-based polyester (c2) having a molecular weight of 800 to 2,000 and a viscosity at 25 ° C. of 50 to 1500 mPa ⁇ s. .
  • the content of the plasticizer (C) is preferably 1 to 60 parts by weight based on 100 parts by weight of the nitrile group-containing copolymer rubber (A).
  • a crosslinkable nitrile rubber composition comprising the above nitrile rubber composition of the present invention and a crosslinking agent. Further, according to the present invention, there is provided a cross-linked rubber obtained by cross-linking the cross-linkable nitrile rubber composition of the present invention.
  • a nitrile group-containing copolymer rubber (A) containing an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit at a ratio of 40 to 50% by weight and an iodine value of 5 to 50 is used.
  • a vinyl chloride resin (B), a plasticizer (C) having a molecular weight of 500 to 2,000, and a compounding agent the method comprising producing a nitrile rubber composition, First mixing in which a part of the total amount of the plasticizer (C) to be contained in the nitrile rubber composition is mixed with the nitrile group-containing copolymer rubber (A) and the vinyl chloride resin (B).
  • a second mixing step in which the composition obtained in the first mixing step is mixed with the rest of the total amount of the plasticizer (C) to be contained in the nitrile rubber composition and the compounding agent, and a second mixing step is performed.
  • a method for producing a nitrile rubber composition comprising:
  • the blending amount of the plasticizer (C) in the first mixing step is 10% of the total amount of the plasticizer (C) contained in the nitrile rubber composition. It is preferable to set it to 90% by weight.
  • the compounding agent preferably contains at least a filler.
  • a nitrile rubber composition which is excellent in processability and can give a rubber crosslinked product having excellent compression set resistance, compression stress retention and cold resistance. Further, according to the present invention, there is provided a crosslinkable nitrile rubber composition and a rubber crosslinked product obtained by using such a nitrile rubber composition, and a method for producing such a nitrile rubber composition. Can also.
  • the nitrile rubber composition of the present invention contains a nitrile group-containing copolymer rubber containing an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit at a ratio of 40 to 50% by weight and an iodine value of 5 to 50 ( A), a vinyl chloride resin (B), and a plasticizer (C) having a molecular weight of 500 to 2,000.
  • the nitrile group-containing copolymer rubber (A) used in the present invention contains an ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit in a proportion of 40 to 50% by weight, and has an iodine value in a range of 5 to 50. There is something.
  • the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer which forms the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit contained in the nitrile group-containing copolymer rubber (A) used in the present invention is: There is no particular limitation, and acrylonitrile; ⁇ -halogenoacrylonitrile such as ⁇ -chloroacrylonitrile and ⁇ -bromoacrylonitrile; ⁇ -alkylacrylonitrile such as methacrylonitrile and ethacrylonitrile; Among these, acrylonitrile and methacrylonitrile are preferred, and acrylonitrile is particularly preferred.
  • the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer may be used alone or in combination of two or more.
  • the content of ⁇ , ⁇ -ethylenically unsaturated nitrile monomer units in the nitrile group-containing copolymer rubber (A) used in the present invention is 40 to 50% by weight based on all monomer units. And preferably 42 to 50% by weight, more preferably 44 to 50% by weight, still more preferably 44 to 49% by weight, and still more preferably 44 to 48% by weight.
  • the obtained cross-linked rubber can have excellent fuel oil resistance.
  • the obtained rubber cross-linked product may be inferior in fuel oil resistance, while if too large, the cold resistance may be reduced. There is.
  • ⁇ , ⁇ -ethylenically unsaturated nitrile in the entire mixture of rubbers having different monomer compositions is used.
  • the content ratio of the monomer unit may be within the above range (the same applies to a copolymerizable monomer unit including a diene monomer unit and / or an ⁇ -olefin monomer unit described later).
  • the nitrile group-containing copolymer rubber of the present invention preferably further contains a diene monomer unit and / or an ⁇ -olefin monomer unit from the viewpoint of improving mechanical properties due to rubber elasticity. .
  • Examples of the diene monomer forming the diene monomer unit include conjugated dienes having 4 or more carbon atoms, such as 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene.
  • conjugated dienes having 5 to 12 carbon atoms such as 1,4-pentadiene and 1,4-hexadiene; Of these, conjugated dienes are preferred, and 1,3-butadiene is more preferred.
  • the ⁇ -olefin monomer forming the ⁇ -olefin monomer unit preferably has 2 to 12 carbon atoms and includes ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1- Hexene, 1-octene and the like are exemplified.
  • One of these diene monomers and ⁇ -olefin monomers may be used alone, or two or more thereof may be used in combination.
  • the lower limit of the content of the diene monomer unit and / or the ⁇ -olefin monomer unit is based on all monomer units. It is preferably at least 40% by weight, more preferably at least 50% by weight, still more preferably at least 51% by weight, still more preferably at least 52% by weight, and the upper limit thereof is preferably at most 60% by weight, more preferably at least 58% by weight. %, More preferably 56% by weight or less.
  • the nitrile group-containing copolymer rubber (A) used in the present invention may contain, in addition to the above ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit, a diene monomer unit and an ⁇ -olefin monomer unit, It may contain units of other monomers copolymerizable with the monomers forming these monomer units.
  • the content ratio of such another monomer unit is preferably 30% by weight or less, more preferably 20% by weight or less, and still more preferably 10% by weight or less, based on all monomer units.
  • Such other copolymerizable monomers include, for example, aromatic vinyl compounds such as styrene, ⁇ -methylstyrene and vinyltoluene; fluoroethyl vinyl ether, fluoropropyl vinyl ether, o-trifluoromethylstyrene, pentafluoro Fluorine-containing vinyl compounds such as vinyl benzoate, difluoroethylene and tetrafluoroethylene; ⁇ -olefin compounds such as ethylene, propylene, 1-butene, 4-methyl-1-pentene, 1-hexene and 1-octene; acrylic acid; ⁇ , ⁇ -ethylenically unsaturated monocarboxylic acids such as methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, fumaric anhydride and anhydrides thereof; methyl (meth) acrylate, (meth) ) Ethyl acrylate, (
  • the nitrile group-containing copolymer rubber (A) used in the present invention has an iodine value of 5 to 50, preferably 8 to 45, more preferably 10 to 40, and still more preferably 18 to 30. If the iodine value of the nitrile group-containing copolymer rubber (A) is too high, the heat resistance and ozone resistance of the obtained rubber cross-linked product may be reduced, and if the iodine value is too low, the obtained rubber cross-linked product Mechanical properties may be reduced.
  • the cross-linking agent when a sulfur-based cross-linking agent is used as the cross-linking agent, by setting the iodine value within the above range, vulcanization can be made good and appropriate, so that the obtained rubber cross-linked product is excellent. While maintaining excellent heat resistance, it is possible to obtain more excellent compression set resistance and compression stress retention.
  • the iodine value of the entire mixture of rubbers having different iodine values may be within the above range.
  • the polymer Mooney viscosity (ML1 + 4, 100 ° C.) of the nitrile group-containing copolymer rubber (A) used in the present invention is preferably 10 to 200, more preferably 15 to 150, and still more preferably 15 to 100.
  • nitrile group-containing copolymer rubber (A) one kind of rubber may be used, or two or more kinds of rubbers may be used in combination. It suffices that the average value of these characteristic values (the average value of the characteristic values taking into account the amount used) be within the above range, but the characteristic value of each of the two or more rubbers used is , Preferably within the above range.
  • the method for producing the nitrile group-containing copolymer rubber (A) used in the present invention is not particularly limited, but the above-mentioned monomers are copolymerized, and if necessary, the carbon-carbon dimer in the resulting copolymer is obtained. It can be produced by hydrogenating a heavy bond.
  • the polymerization method is not particularly limited, and may be a known emulsion polymerization method or a solution polymerization method. From the viewpoint of industrial productivity, the emulsion polymerization method is preferable.
  • a commonly used polymerization auxiliary material can be used in addition to the emulsifier, the polymerization initiator, and the molecular weight modifier.
  • the vinyl chloride resin (B) used in the present invention may be any one as long as the main constituent monomer constituting the resin is vinyl chloride, and the content of the vinyl chloride monomer unit is 50 to 100% by weight. Preferably, it is 60 to 100% by weight, more preferably 70 to 100% by weight.
  • the obtained rubber crosslinked product can be excellent in ozone resistance, fuel oil swelling resistance, and fuel oil permeability.
  • the degree of polymerization of the vinyl chloride resin (B) is not particularly limited, but the average degree of polymerization measured by a solution viscosity method prescribed in JIS K6720-2: 1999 is preferably 400 to 3000, more preferably 600 to 2000. .
  • the average degree of polymerization is in the above range, the ozone resistance, fuel oil swelling resistance, and fuel oil permeability of the obtained rubber cross-linked product are further improved while improving the processability of the nitrile rubber composition. Can be.
  • the content of the vinyl chloride resin (B) in the nitrile rubber composition of the present invention is preferably 5 to 120 parts by weight, more preferably 10 to 100 parts by weight, based on 100 parts by weight of the nitrile group-containing copolymer rubber (A).
  • the amount is 110 parts by weight, more preferably 20 to 100 parts by weight, still more preferably 25 to 80 parts by weight, particularly preferably 40 to 70 parts by weight.
  • the nitrile rubber composition of the present invention contains a plasticizer (C) having a molecular weight of 500 to 2,000 in addition to the nitrile group-containing copolymer rubber (A) and the vinyl chloride resin (B).
  • the plasticizer (C) having a molecular weight of 500 to 2,000 (hereinafter, appropriately referred to as “plasticizer (C)”) is used as the above-mentioned nitrile group-containing copolymer rubber (A) and vinyl chloride resin (B).
  • the nitrile rubber composition can have excellent workability, and furthermore, the obtained rubber
  • the crosslinked product can be made excellent in compression set resistance, compression stress retention and cold resistance.
  • the above-mentioned nitrile group-containing copolymer rubber (A) and vinyl chloride resin (B) are used, the effects derived from them, that is, the obtained rubber cross-linked product is used as a fuel-resistant oil It also has the effect of being able to have excellent swelling properties, fuel oil permeability, ozone resistance and heat resistance.
  • the obtained rubber cross-linked product in addition to compression set resistance, can also be excellent in compressive stress retention, so that it can be used for compression, particularly for metal-bonded parts. It can be suitably used for fuel hose applications having a crimped portion with a rubber crosslinked product.
  • the plasticizer (C) is not particularly limited as long as it has a molecular weight in the range of 500 to 2,000. From the viewpoint that the obtained rubber cross-linked product can further increase the compressive stress retention, the polyetherester (c1) represented by the formula (1) or the adipic acid-based polyester (c2) having a molecular weight of 800 to 2,000 and a viscosity at 25 ° C. of 50 to 1500 mPa ⁇ s is preferable.
  • R 1 is each independently a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 15 carbon atoms. Particularly preferred is a hydrocarbon group having 1 to 10 carbon atoms.
  • R 2 is each independently a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms, preferably a hydrogen atom or a hydrocarbon group having 1 to 7 carbon atoms. And more preferably a hydrogen atom.
  • n is an integer of 1 to 40, preferably an integer of 2 to 30, and more preferably an integer of 3 to 30.
  • polyetherester (c1) represented by the general formula (1) for example, a corresponding alkylene oxide polymer is obtained, and a terminal hydroxyl group of the obtained polymer is reacted with a corresponding carboxylic acid. Thus, it can be produced by esterification.
  • the molecular weight of the polyetherester (c1) represented by the general formula (1) is in the range of 500 to 1200 from the viewpoint that the obtained rubber crosslinked product can have a higher compressive stress retention. Those having a molecular weight in the range of 520 to 900 are more preferable.
  • the polyetherester (c1) represented by the general formula (1) has a viscosity at a temperature of 25 ° C. Those in the range of 15 to 300 mPa ⁇ s are preferable, those in the range of 22 to 150 mPa ⁇ s are more preferable, and those in the range of 25 to 100 mPa ⁇ s are particularly preferable.
  • polyetherester (c1) represented by the general formula (1) those having a flash point in the range of 216 to 300 ° C. are preferable, and those having a flash point in the range of 220 to 260 ° C. are more preferable. preferable.
  • an adipic acid-based polyester (c2) having a molecular weight of 800 to 2,000 and a viscosity at a temperature of 25 ° C. of 50 to 1500 mPa ⁇ s (hereinafter referred to as “adipic acid-based polyester (c2 ) ”) Is also preferably used.
  • adipic acid-based polyester (c2) a reaction product of an adipic acid, which is a dicarboxylic acid, and an alcohol having a molecular weight and a viscosity at a temperature of 25 ° C. within the above ranges is used. There is no particular limitation as long as it exists.
  • the adipic acid-based polyester (c2) is, for example, a reaction product of adipic acid and a polyhydric alcohol, or a product obtained by further reacting a monohydric alcohol or a monocarboxylic acid in addition to adipic acid and a polyhydric alcohol. You may.
  • Examples of the dihydric alcohol include ethylene glycol, propylene glycol, butanediol, 1.6-hexanediol and the like.
  • Examples of the monohydric alcohol include nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, hexadecanol, octadecanol and the like.
  • Examples of the monovalent carboxylic acid include nonanoic acid, capric acid, undecylic acid, and lauric acid.
  • the adipic acid-based polyester (c2) may be any polyester having a molecular weight of 800 to 2,000 and a viscosity at a temperature of 25 ° C. of 50 to 1500 mPa ⁇ s. From the viewpoint that the molecular weight can be increased, those having a molecular weight in the range of 900 to 1600 are preferable, and those having a molecular weight in the range of 1000 to 1300 are more preferable. Further, from the viewpoint that the obtained rubber cross-linked product can further increase the compressive stress retention, the viscosity at a temperature of 25 ° C. is preferably in the range of 500 to 1200 mPa ⁇ s, and more preferably in the range of 650 to 1000 mPa ⁇ s.
  • adipic acid-based polyester (c2) those having a flash point in the range of 216 to 300 ° C. are preferable, and those having a flash point in the range of 220 to 260 ° C. are more preferable.
  • plasticizer (C) one type may be used alone, or two or more types may be used in combination.
  • plasticizer (C) two or more kinds of polyetheresters (c1) represented by the above general formula (1) may be used, or two or more kinds may be used.
  • the adipic acid-based polyester (c2) may be used, or a combination of the polyetherester (c1) represented by the general formula (1) and the adipic acid-based polyester (c2) may be used. .
  • the content of the plasticizer (C) in the nitrile rubber composition of the present invention is preferably 1 to 60 parts by weight, more preferably 3 to 55 parts by weight, based on 100 parts by weight of the nitrile group-containing copolymer rubber (A). Parts by weight, more preferably 5 to 50 parts by weight, even more preferably 8 to 40 parts by weight, particularly preferably 10 to 40 parts by weight, most preferably 15 to 30 parts by weight.
  • the nitrile rubber composition of the present invention preferably further contains a stabilizer.
  • the stabilizer may be any compound that acts as a stabilizer for the vinyl chloride resin, and is not particularly limited.
  • Calcium-zinc stabilizer, calcium-magnesium-zinc stabilizer, barium-zinc stabilizer, tin-based stabilizer Examples include stabilizers, lead stabilizers, hydrotalcite stabilizers, and zeolite stabilizers. Of these, calcium-magnesium-zinc stabilizers and hydrotalcite stabilizers are preferred. Magnesium-zinc stabilizers are more preferred.
  • the content of the stabilizer in the nitrile rubber composition of the present invention is preferably 1 to 50 parts by weight, more preferably 2 to 45 parts by weight, further preferably 5 to 100 parts by weight based on 100 parts by weight of the vinyl chloride resin (B). 4545 parts by weight.
  • the nitrile rubber composition of the present invention may contain various compounding agents used in the rubber field.
  • a compounding agent typically includes a filler.
  • Fillers include ⁇ , ⁇ -ethylenic substances such as carbon black, silica, calcium carbonate, aluminum silicate, magnesium silicate, calcium silicate, magnesium oxide, short fibers, zinc (meth) acrylate and magnesium (meth) acrylate. And unsaturated carboxylic acid metal salts. Among them, carbon black and silica are preferred, and carbon black is more preferred, from the viewpoint that the mechanical strength can be further increased.
  • the filler a filler whose surface is surface-treated with a surface treatment agent or the like may be used.
  • Carbon black is not particularly limited, but examples thereof include furnace black, acetylene black, thermal black, channel black, and graphite.
  • furnace black is preferably used, and specific examples thereof include SAF, ISAF, ISAF-HS, ISAF-LS, HAF, HAF-HS, HAF-LS, FEF, SRF, FT, and MT. No. These may be used alone or in combination of two or more.
  • Silica is not particularly limited, but for example, dry-process white carbon, wet-process white carbon, colloidal silica, precipitated silica, surface-treated silica, and the like can be used. Alternatively, a carbon-silica dual phase filler having silica supported on the surface of carbon black may be used.
  • the content of the filler in the nitrile rubber composition of the present invention is preferably 10 to 80 parts by weight, more preferably 15 to 75 parts by weight, based on 100 parts by weight of the nitrile group-containing copolymer rubber (A). More preferably, the amount is 20 to 70 parts by weight.
  • the nitrile rubber composition of the present invention preferably further contains a cross-linking agent.
  • a cross-linking agent By adding a cross-linking agent, the nitrile rubber composition of the present invention becomes a cross-linkable composition, It can be a nitrile rubber composition.
  • the crosslinking agent is not particularly limited, and includes, for example, a sulfur-based crosslinking agent and an organic peroxide crosslinking agent.
  • a sulfur-based crosslinking agent is preferred.
  • Sulfur-based crosslinking agents include sulfur such as powdered sulfur, sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur and insoluble sulfur; sulfur chloride, sulfur dichloride, 4,4′-dithiodimorpholine, and 4,4 ′ -Sulfur-containing compounds such as tetrathiodimorpholine, 4-morpholinyl morpholinodithiothioate, alkylphenol disulfide, dibenzothiazyl disulfide, caprolactam disulfide, phosphorus-containing polysulfide, and high molecular polysulfide; tetramethylthiuram disulfide, selenium dimethyldithiocarbamate Sulfur donating compounds; and the like.
  • 4,4′-dithiodimorpholine, 4,4′-tetrathiodimorpholine from the viewpoint that the obtained crosslinkable rubber composition can be more excellent in crosslink stability.
  • Sulfur-containing compounds having a morpholine structure such as 4-morpholinyl morpholinodithioformate are preferred, and 4,4'-dithiodimorpholine is particularly preferred.
  • the content of the crosslinking agent in the nitrile rubber composition (crosslinkable nitrile rubber composition) of the present invention is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the nitrile group-containing copolymer rubber (A). , More preferably 0.2 to 8 parts by weight, even more preferably 0.5 to 6 parts by weight.
  • cross-linking assistants such as stearic acid; guanidine-based, thiuram-based, aldehyde- It is preferable to use an amine-based, aldehyde-ammonia-based, thiazole-based, sulfenamide-based, or thiourea-based crosslinking accelerator;
  • the amount of these crosslinking aids and crosslinking accelerators used is preferably in the range of 0.1 to 20 parts by weight based on 100 parts by weight of the nitrile copolymer rubber (A).
  • the nitrile rubber composition (crosslinkable nitrile rubber composition) of the present invention may contain other additives such as a crosslinking retarder, an antioxidant, a reinforcing agent, a lubricant, an adhesive, a lubricant, and a processing aid. And additives such as a flame retardant, a fungicide, an antistatic agent, and a coloring agent.
  • the nitrile rubber composition (crosslinkable nitrile rubber composition) of the present invention contains a rubber other than the nitrile group-containing copolymer rubber (A) as a compounding agent as long as the effects of the present invention are not impaired. May be.
  • Examples of the rubber other than the nitrile group-containing copolymer rubber (A) include acrylic rubber, ethylene-acrylic acid copolymer rubber, fluororubber, styrene-butadiene copolymer rubber, polybutadiene rubber, ethylene-propylene copolymer rubber, Examples include ethylene-propylene-diene terpolymer rubber, epichlorohydrin rubber, urethane rubber, chloroprene rubber, silicone rubber, fluorosilicone rubber, chlorosulfonated polyethylene rubber, natural rubber, and polyisoprene rubber.
  • the compounding amount is preferably 30 parts by weight or less, more preferably 20 parts by weight or less, based on 100 parts by weight of the nitrile group-containing copolymer rubber (A). And more preferably 10 parts by weight or less.
  • the compound Mooney viscosity (ML1 + 4, 100 ° C.) of the nitrile rubber composition (crosslinkable nitrile rubber composition) of the present invention is preferably 20 to 150, more preferably 30 to 120, and further preferably 40 to 100.
  • a plasticizer (C) having a molecular weight of 500 to 2,000 is compounded, as described above, the ⁇ , ⁇ -ethylenically unsaturated nitrile monopolymer is used as a nitrile group-containing copolymer rubber.
  • the nitrile rubber composition (crosslinkable nitrile rubber composition) of the present invention is obtained by mixing the above-described nitrile group-containing copolymer rubber (A), vinyl chloride resin (B), and plasticizer (C). Can be manufactured.
  • the nitrile rubber composition (crosslinkable nitrile rubber composition) of the present invention contains a compounding agent such as a filler or a crosslinking agent
  • the following steps are preferably employed. That is, a part of the total amount of the plasticizer (C) contained in the nitrile rubber composition (crosslinkable nitrile rubber composition) is partially converted into a nitrile group-containing copolymer rubber (A) and a vinyl chloride resin (B).
  • a first mixing step of mixing In the composition obtained in the first mixing step, the rest of the total amount of the plasticizer (C) contained in the nitrile rubber composition (crosslinkable nitrile rubber composition) and a compounding agent are blended and mixed. It is preferable to include two mixing steps.
  • nitrile rubber composition crosslinkable nitrile rubber composition
  • nitrile group-containing copolymer rubber (A) and the vinyl chloride resin (B) a compounding agent such as a filler or a cross-linking agent is added together with the remaining plasticizer (C), and the process of mixing is employed to appropriately suppress bleeding of the plasticizer (C). , In a desired amount.
  • the plasticizer (C) is used in an amount of preferably 1 to 60 parts by weight, more preferably 3 to 55 parts by weight, and still more preferably 5 to 55 parts by weight, based on 100 parts by weight of the nitrile group-containing copolymer rubber (A).
  • the amount can be 50 parts by weight, more preferably 8 to 40 parts by weight, particularly preferably 10 to 40 parts by weight, and most preferably 15 to 30 parts by weight.
  • the blending amount of the plasticizer (C) in the first mixing step is 10 to 90% by weight of the total amount of the plasticizer (C) contained in the nitrile rubber composition (crosslinkable nitrile rubber composition). %, Preferably 20 to 90% by weight, more preferably 25 to 85% by weight, and particularly preferably 55 to 75% by weight.
  • most of the composition obtained in the first mixing step contains a nitrile group-containing copolymer rubber (A), a vinyl chloride resin (B), and a plasticizer (C). It is preferable that the components are mixed so that the ratio of these components, specifically, the total content of these components is preferably 95% by weight or more, more preferably 99% by weight or more. That is, when the content is preferably 5% by weight or less, more preferably 1% by weight or less, a mode may be adopted in which a compounding agent such as a stabilizer is contained.
  • the mixing method in the first mixing step is not particularly limited, but the nitrile group-containing copolymer rubber (A), vinyl chloride resin (B), and plasticizer (C) can be mixed with a Banbury mixer, an intermixer, a kneader, a roll, or the like. And a method of kneading using the same.
  • the mixing temperature in the first mixing step is not particularly limited, but is preferably from 40 to 200 ° C, more preferably from 50 to 190 ° C.
  • the mixing time in the first mixing step is not particularly limited, but is preferably 3 to 20 minutes, more preferably 5 to 15 minutes.
  • the mixing method in the second mixing step is not particularly limited, but the composition obtained in the first mixing step, the plasticizer (C), and the compounding agent such as a filler and a crosslinking agent are mixed with a Banbury mixer, an intermixer, and the like. , A kneader, a roll, or the like.
  • a component excluding a crosslinking agent and a component unstable to heat is replaced with a Banbury mixer, an intermixer, a kneader, or the like.
  • the method of the present invention is preferably a method in which the mixture is primarily mixed by a mixer, and then transferred to a roll or the like, and a crosslinking agent or a component unstable to heat is added to the mixture to perform a secondary mixing.
  • the mixing temperature in the second mixing step (the mixing temperature in the primary mixing and the secondary mixing) is not particularly limited, but is preferably 40 to 100 ° C, more preferably 40 to 80 ° C.
  • the mixing time (the total mixing time of the primary mixing and the secondary mixing) in the second mixing step is not particularly limited, but is preferably 3 to 20 minutes, more preferably 3 to 15 minutes.
  • the cross-linked rubber of the present invention is obtained by cross-linking the cross-linkable nitrile rubber composition of the present invention described above (that is, a composition obtained by blending a cross-linking agent with the nitrile rubber composition of the present invention).
  • the cross-linked rubber of the present invention is formed using the cross-linkable nitrile rubber composition of the present invention, and molded by a molding machine corresponding to a desired shape, for example, an extruder, an injection molding machine, a compressor, a roll, and the like, and heated.
  • a cross-linking reaction is carried out, and the shape can be fixed as a cross-linked product.
  • crosslinking may be performed after molding in advance, or crosslinking may be performed simultaneously with molding.
  • the molding temperature is usually from 10 to 200 ° C, preferably from 25 to 120 ° C.
  • the crosslinking temperature is usually from 100 to 200 ° C., preferably from 130 to 190 ° C.
  • the crosslinking time is usually from 1 minute to 24 hours, preferably from 2 minutes to 1 hour.
  • the surface may be crosslinked, but the inside may not be sufficiently crosslinked. Therefore, secondary crosslinking may be performed by further heating.
  • a heating method a general method used for rubber crosslinking, such as press heating, steam heating, oven heating, and hot air heating, may be appropriately selected.
  • the rubber cross-linked product of the present invention thus obtained is obtained by using the cross-linkable nitrile rubber composition of the present invention described above, wherein the ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit described above is used.
  • the properties derived from the nitrile group-containing copolymer rubber (A) having a relatively high iodine value and the vinyl chloride resin (B), that is, the obtained rubber cross-linked product has a fuel oil swelling resistance and a fuel resistance. In addition to the properties of being excellent in oil permeability, ozone resistance and heat resistance, it has excellent compression set resistance, compressive stress retention and cold resistance.
  • the rubber crosslinked product of the present invention makes use of such characteristics and utilizes O-rings, packings, diaphragms, oil seals, shaft seals, bearing seals, well head seals, shock absorber seals, seals for pneumatic equipment, air conditioners, and the like.
  • Seals for rolling devices rolling bearings, automotive hub units, automotive water pumps, linear guide devices, ball screws, etc.), valves and valve seats, various sealing materials such as BOP (Blow Out Preventer) and platters; Intake manifold and sieve Intake manifold gasket to be installed at the connection between cylinder head and cylinder head, cylinder head gasket to be installed at the connection between cylinder block and cylinder head, rocker cover gasket to be installed at the connection between rocker cover and cylinder head, oil pan Oil pan gasket to be attached to cylinder block or connection to transmission case, gasket for fuel cell separator to be fitted between a pair of housings sandwiching unit cell with positive electrode, electrolyte plate and negative electrode, for top cover of hard disk drive Various gaskets such as gaskets; various rolls such as printing rolls
  • the crosslinked rubber product of the present invention comprises a nitrile group-containing copolymer rubber (A) having a relatively high ⁇ , ⁇ -ethylenically unsaturated nitrile monomer unit and a relatively low iodine value, and vinyl chloride.
  • A nitrile group-containing copolymer rubber
  • B vinyl chloride
  • the resulting rubber cross-linked product is excellent in fuel oil swelling resistance, fuel oil permeation resistance, ozone resistance and heat resistance, as well as compression set resistance. Since it is excellent in compressive stress retention and cold resistance, it can be suitably used for fuel hose applications.
  • a laminate of two or more layers having at least one layer made of the crosslinked rubber of the present invention.
  • the other layers forming the laminate include fluorine rubber, chloroprene rubber, hydrin rubber, chlorosulfonated polyethylene rubber, acrylic rubber, ethylene-acrylic acid copolymer, ethylene-propylene copolymer, ethylene -Propylene-diene terpolymer, butyl rubber, isoprene rubber, natural rubber, styrene-butadiene copolymer, fluororesin, polyamide resin, polyvinyl alcohol, ethylene-vinyl acetate copolymer resin, ethylene-vinyl alcohol copolymer resin , Polybutylene naphthalate, polyphenylene sulfide, polyolefin resin, polyester resin and the like.
  • Mooney viscosity (compound Mooney) of the crosslinkable nitrile rubber composition was measured according to JIS K6300-1 (unit: [ML1 + 4, 100 ° C.]).
  • T 10 is the "maximum torque MH- minimum torque ML" is taken as 100%, the torque from the minimum torque ML, means the time required for 10% increase, as the value of T 10 is large, It can be judged that the crosslinking speed is slow and the crosslinking stability is excellent.
  • the crosslinkable nitrile rubber composition was placed in a mold having a length of 15 cm, a width of 15 cm, and a depth of 0.2 cm, and press-molded at 160 ° C. for 20 minutes while applying a pressure of 10 MPa to obtain a sheet-like rubber cross-linked product. .
  • a test piece was prepared by punching out the obtained sheet cross-linked rubber with a JIS No. 3 dumbbell. Then, using the obtained test piece, the tensile strength and elongation at break of the rubber crosslinked product were measured according to JIS K6251, and a durometer hardness tester (type A) was used according to JIS K6253-3: 2012. The hardness of the rubber crosslinked product was measured in each case.
  • ⁇ Compression stress relaxation test> The crosslinkable nitrile rubber composition was pressed using a mold at a temperature of 160 ° C. for 30 minutes while applying pressure, thereby obtaining a columnar rubber crosslinked product having a diameter of 29 mm and a height of 12.5 mm. Then, a compression stress relaxation test was performed by maintaining the obtained crosslinked rubber in an environment of 125 ° C. in a state of being compressed by 25%. Then, 30 minutes after the start of the test, the compressive stress of the rubber crosslinked product was measured, and this was taken as the initial stress. The compressive stress 72 hours after the start of the test was measured, and the compressive stress retention was determined according to the following equation. .
  • Compressive stress retention [%] (Compressive stress [MPa] after 72 hours / Initial stress [MPa]) ⁇ 100
  • ⁇ Compressive stress retention
  • Example 1 (First mixing step) Using a Banbury mixer, 30 parts of hydrogenated acrylonitrile-butadiene rubber (A-1) (trade name “Zetpol 0020”, acrylonitrile monomer unit 49% by weight, iodine value 23), hydrogenated acrylonitrile-butadiene rubber (A- 2) 30 parts of (trade name “Zetpol 1020”, acrylonitrile monomer unit 44% by weight, iodine value 24) 30 parts, vinyl chloride resin (trade name "TK1300", Shin-Etsu Chemical Co., Ltd., average polymerization degree 1300) 40 parts, 0.5 parts of a calcium-magnesium-zinc-based stabilizer (trade name “ADEKA STAB RUP-110”, manufactured by ADEKA) and polyetherester (c1-1) (trade name “ADEKA SIZER RS-700”, manufactured by ADEKA) Molecular weight: 550, viscosity at 25 ° C .: 30 mPa
  • the mixture of the hydrogenated acrylonitrile-butadiene rubber (A-1) and the hydrogenated acrylonitrile-butadiene rubber (A-2) has an acrylonitrile monomer unit amount of 46.5% by weight and an iodine value of the mixture. 23.5.
  • Example 2 In the first mixing step and the second mixing step, the plasticizer was replaced with polyetherester (c1-1) (trade name “ADEKASIZER RS-700”, manufactured by ADEKA), and both were mixed with polyetherester (c1). -2) (trade name “ADEKA SIZER RS-735", manufactured by ADEKA Corporation, molecular weight: 850, viscosity at 25 ° C: 80 mPa ⁇ s, flash point: 252 ° C, polyether ester represented by the above general formula (1))
  • c1-1 polyetherester
  • -2 trade name “ADEKA SIZER RS-735”
  • a crosslinkable nitrile rubber composition was obtained and evaluated in the same manner as in Example 1 except that the same amount of (c1)) was used. Table 1 shows the results.
  • Example 3 In the first mixing step and the second mixing step, as the plasticizer, in place of the polyetherester (c1-1) (trade name “ADEKASIZER RS-700”, manufactured by ADEKA Corporation), any of adipic acid-based polyester ( c2-1) (trade name “ADEKASIZER PN-170”, manufactured by ADEKA Corporation, molecular weight: 1100, viscosity at 25 ° C .: 800 mPa ⁇ s, flash point: 244 ° C., adipic acid-based polyester (c2)) used in the same amount
  • a crosslinkable nitrile rubber composition was obtained in the same manner as in Example 1 except that the evaluation was performed, and the evaluation was performed in the same manner. Table 1 shows the results.
  • Example 4 In the second mixing step, the same procedure as in Example 1 was carried out, except that 15 parts of a calcium-magnesium-zinc-based stabilizer (trade name “ADK STAB RUP-110”, manufactured by ADEKA) was used instead of 5 parts of zinc oxide. Thus, a crosslinkable nitrile rubber composition was obtained and similarly evaluated. Table 1 shows the results.
  • adipic acid polyether ester was used instead of polyether ester (c1-1) (trade name “ADEKASIZER RS-700” manufactured by ADEKA). (Product name “ADEKASIZER RS-107”, manufactured by ADEKA Corporation, molecular weight: 434, viscosity at 25 ° C .: 20 mPa ⁇ s, flash point: 215 ° C.), except that the same amount was used. A crosslinkable nitrile rubber composition was obtained and evaluated in the same manner. Table 1 shows the results.
  • nitrile group-containing copolymer rubber (A) containing ⁇ , ⁇ -ethylenically unsaturated nitrile monomer units at a ratio of 40 to 50% by weight and an iodine value of 5 to 50
  • the nitrile rubber composition crosslinkable nitrile rubber composition
  • the vinyl chloride resin (B) and the plasticizer (C) having a molecular weight of 500 to 2,000
  • the compound Mooney viscosity increases.

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Abstract

L'invention concerne une composition de caoutchouc nitrile qui comprend un caoutchouc copolymère contenant un groupe nitrile (A) contenant des motifs d'un monomère nitrile α,β-éthyléniquement insaturé en une proportion de 40 à 50 % en poids et présentant un indice d'iode de 5 à 50, une résine de chlorure de vinyle (B), et un plastifiant (C) ayant une masse moléculaire de 500 à 2 000.
PCT/JP2019/036482 2018-09-27 2019-09-18 Composition de caoutchouc nitrile et procédé de production de composition de caoutchouc nitrile WO2020066770A1 (fr)

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Citations (7)

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Publication number Priority date Publication date Assignee Title
JPS59100152A (ja) * 1982-11-30 1984-06-09 Toyoda Gosei Co Ltd 塩化ビニル樹脂組成物
JPH06263924A (ja) * 1993-03-16 1994-09-20 Nippon Zeon Co Ltd ゴム組成物
JPH07292195A (ja) * 1994-04-27 1995-11-07 Du Pont Mitsui Polychem Co Ltd 軟質ポリ塩化ビニル樹脂組成物の製造方法および軟質ポリ塩化ビニル組成物成形品の製造方法
JP2006170343A (ja) * 2004-12-16 2006-06-29 Mitsubishi Motors Corp 自動車用ホース
WO2013042764A1 (fr) * 2011-09-21 2013-03-28 日本ゼオン株式会社 Composition de caoutchouc de copolymère de nitrile et produit de réticulation de caoutchouc
JP2017511758A (ja) * 2014-02-13 2017-04-27 シーカ テクノロジー アクチェンゲゼルシャフト 可塑化ｐｖｃ半製品の製造方法
JP2018052054A (ja) * 2016-09-30 2018-04-05 住友理工株式会社 ホースの製造方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103502362B (zh) 2011-03-31 2017-02-22 新田株式会社 具有高耐久性的热塑性树脂组合物

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59100152A (ja) * 1982-11-30 1984-06-09 Toyoda Gosei Co Ltd 塩化ビニル樹脂組成物
JPH06263924A (ja) * 1993-03-16 1994-09-20 Nippon Zeon Co Ltd ゴム組成物
JPH07292195A (ja) * 1994-04-27 1995-11-07 Du Pont Mitsui Polychem Co Ltd 軟質ポリ塩化ビニル樹脂組成物の製造方法および軟質ポリ塩化ビニル組成物成形品の製造方法
JP2006170343A (ja) * 2004-12-16 2006-06-29 Mitsubishi Motors Corp 自動車用ホース
WO2013042764A1 (fr) * 2011-09-21 2013-03-28 日本ゼオン株式会社 Composition de caoutchouc de copolymère de nitrile et produit de réticulation de caoutchouc
JP2017511758A (ja) * 2014-02-13 2017-04-27 シーカ テクノロジー アクチェンゲゼルシャフト 可塑化ｐｖｃ半製品の製造方法
JP2018052054A (ja) * 2016-09-30 2018-04-05 住友理工株式会社 ホースの製造方法

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