Resin composition, method for producing same, and hose for transporting refrigerant

Abstract

Provided is a resin composition having excellent heat resistance and water vapor barrier properties. The resin composition contains a resin-containing matrix and a rubber-containing domain, and is characterized in that the resin composition contains a rubber cross-linking agent, and when the torque when a rubber kneaded product obtained by kneading rubber and the rubber cross-linking agent is heated at 200 DEG C and 230 DEG C for 10 minutes is measured over time using a vibratory vulcanization testing machine, the torque of the rubber kneaded product is less than the torque of the rubber cross-linking agent when the rubber kneaded product is heated at 200 DEG C and 230 DEG C for 10 minutes. The torque S '10 min, 200 DEG C after 10 minutes at 200 DEG C is 3.0 dN.m or more, and the relationship of S' 10 min, the torque S '10 min after 10 minutes at 200 DEG C and 230 DEG C, the maximum value S' MAX, 200 DEG C of the torque for 0-10 minutes at 230 DEG C and 200 DEG C, and the maximum value S 'MAX, 230 DEG C of the torque for 0-10 minutes at 230 DEG C satisfies S' 10 min, 200 DEG C / S 'MAX, 200 DEG C > = 0.9 and S' 10 min, 230 DEG C / S 'MAX, 230 DEG C > = 0.9.

Description

Technical Field

[0001] The present invention relates to a resin composition, a method for producing the same, and a hose for transporting a refrigerant. More specifically, the present invention relates to a resin composition having excellent heat resistance and water vapor barrier properties that can be used to produce a hose for transporting a refrigerant used in an automobile air conditioner, a method for producing the resin composition, and a hose for transporting a refrigerant produced using the resin composition. Background Art

[0002] As the demand for lightweight cars continues to increase, there is a measure to achieve lightweighting by replacing rubber with resin with high barrier properties and making the wall thinner for rubber hoses that have been used in cars. In particular, the main material of the refrigerant delivery hose of existing car air conditioners is rubber. If this main material can be replaced with resin with high barrier properties, lightweighting can be achieved.

[0003] Japanese Patent Application Laid-Open No. 4-145284 (Patent Document 1) describes that an outer tube of a hose for conveying a refrigerant such as Freon gas is formed using a thermoplastic elastomer composed of a thermoplastic polyolefin resin and EPDM or butyl rubber.

[0004] Prior Art Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 4-145284 Summary of the invention

[0006] Problems to be solved by the invention

[0007] Automobile air conditioners are installed in a limited and narrow space in the automobile, so the refrigerant delivery hose is required to be highly flexible and easy to install even in a narrow space. In addition, the penetration of water vapor from the outside of the hose causes water to freeze inside the air conditioner, so the material forming the outer tube of the refrigerant delivery hose needs to have excellent water vapor barrier properties. In addition, it is also required to be durable enough to be used for a long time in the high temperature and high humidity environment of the engine room.

[0008] However, since the thermoplastic elastomer constituting the outer tube of the resin hose described in Patent Document 1 uses a thermoplastic polyolefin resin, the heat resistance is not necessarily sufficient.

[0009] An object of the present invention is to provide a resin composition having excellent heat resistance and water vapor barrier properties that can be used to produce an outer tube of a resin hose.

[0010] Means for solving problems

[0011] The present invention (I) relates to a resin composition comprising a matrix containing a resin and a domain containing a rubber, wherein the resin composition contains a rubber crosslinking agent, and when a rubber compound in which rubber and a rubber crosslinking agent are mixed is heated at 200° C. and 230° C. for 10 minutes over time using a vibration type vulcanization tester, the torque S′ after 10 minutes at 200° C. is 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.9.

[0012] The present invention (II) relates to a method for producing a resin composition containing a matrix containing a resin and a structural domain containing a rubber, characterized in that the method comprises melt-kneading a resin, a rubber and a rubber crosslinking agent, and measuring the torque of a rubber mixture kneaded with the rubber and the rubber crosslinking agent when heated at 200° C. and 230° C. for 10 minutes using a vibration vulcanization tester over time, and the torque S′ after 10 minutes at 200° C. is 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.9.

[0013] The present invention (III) relates to a hose for transporting refrigerant comprising an inner layer, a reinforcing layer and an outer layer, wherein the outer layer contains the resin composition described in the present invention (I).

[0014] The present invention includes the following technical solutions.

[0015] [1] A resin composition comprising a matrix containing a resin and a domain containing a rubber, wherein the resin composition contains a rubber crosslinking agent, and when a rubber mixture containing a rubber and a rubber crosslinking agent is heated at 200°C and 230°C for 10 minutes over time using a vibration vulcanization tester, the torque S′ after 10 minutes at 200°C is10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.9.

[0016] [2] The resin composition according to [1], wherein the water vapor permeability of the resin is 3.0 g·mm / (m 2 24h) or less.

[0017] [3] The resin composition according to [1] or [2], wherein the water vapor permeability of the rubber is 3.0 g·mm / (m 2 24h) or less.

[0018] [4] The resin composition according to any one of [1] to [3], wherein the rubber has a polyisobutylene skeleton.

[0019] [5] The resin composition according to any one of [1] to [4], wherein the rubber crosslinking agent contains zinc white and an alkylphenol formaldehyde resin.

[0020] [6] The resin composition according to any one of [1] to [5], wherein the resin is a polyolefin resin.

[0021] [7] The resin composition according to any one of [1] to [6], wherein the resin contains a silane-modified polyolefin resin.

[0022] [8] The resin composition according to [7], wherein the resin composition contains a silanol condensation catalyst.

[0023] [9] The resin composition according to any one of [1] to [8], wherein the resin composition has a tensile strength at 150°C of 1.5 MPa or more.

[0024]

[10] The resin composition according to any one of [1] to [9], wherein the water vapor permeability of the resin composition is 3.0 g·mm / (m 2 24h) or less.

[0025]

[11] The resin composition according to any one of [1] to

[10] , wherein the 10% modulus of the resin composition at room temperature is 10 MPa or less.

[0026]

[12] A method for producing a resin composition comprising a matrix containing a resin and a domain containing a rubber, the method comprising melt-kneading a resin, a rubber and a rubber crosslinking agent, and measuring the torque of the rubber mixture kneaded with the rubber and the rubber crosslinking agent when heated at 200°C and 230°C for 10 minutes using a vibration vulcanization tester over time, wherein the torque S' after 10 minutes at 200°C is 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.9.

[0027]

[13] A refrigerant transport hose comprising an inner layer, a reinforcement layer and an outer layer, wherein the outer layer comprises the resin composition according to any one of [1] to

[11] .

[0028] Effects of the Invention

[0029] The resin composition of the present invention is excellent in heat resistance and water vapor barrier properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a cross-sectional view of a hose for transporting refrigerant.

[0031] Figure 2 It is a torque-time curve, showing an example of a case where there is no reversion.

[0032] Figure 3 is a torque-time curve showing an example of a situation with reversal. DETAILED DESCRIPTION

[0033] The resin composition of the present invention comprises a matrix containing a resin and a domain containing a rubber, and further comprises a rubber crosslinking agent.

[0034] The resin composition of the present invention is characterized in that when a rubber compound obtained by mixing rubber and a rubber crosslinking agent is heated at 200°C and 230°C for 10 minutes over time using a vibration type vulcanization tester, the torque S′ after 10 minutes at 200°C is 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutesMAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.9.

[0035] Figure 2 The torque-time curve obtained when the torque of the rubber compound kneaded with the rubber and the rubber crosslinking agent of Example 1 is heated at 200°C or 230°C for 10 minutes using a vibration vulcanization tester over time is shown. In the torque-time curve at 200°C, no maximum value of the torque is observed before 10 minutes have passed. The situation where no maximum value of the torque is observed before 10 minutes has passed is also referred to as "no reversal" or "no crosslinking reversal". If there is no reversal, the strength when hot is good, specifically, the tensile strength at 150°C is large.

[0036] Figure 3 The torque-time curve obtained by measuring the torque of the rubber compound of Comparative Example 1 mixed with the rubber and the rubber crosslinking agent at 200°C or 230°C for 10 minutes using a vibration vulcanization tester over time. In the torque-time curve, the maximum value S' of the torque is observed before 10 minutes have passed. MAX The case where the maximum torque value is observed before 10 minutes has passed is also referred to as "reversal" or "crosslinking reversal". In the case of reversal, the torque S' after 10 minutes is 10min Much smaller than S' MAX When the heat strength is poor, specifically, the tensile strength at 150°C is small.

[0037] The resin composition of the present invention has a torque S' after 10 minutes at 200°C in the above torque-time curve. 10min,200℃ It is 3.0 dN·m or more, preferably 3.1 to 20.0 dN·m, and more preferably 3.2 to 15.0 dN·m. 10min,200℃ In this numerical range, the heat resistance is excellent, that is, the hot strength, specifically, the tensile strength at 150° C. is large.

[0038] The resin composition of the present invention, in the above torque-time curve, S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies the following equations (1) and (2):

[0039] S' 10min,200℃ / S'MAX,200℃ ≥0.9···(1)

[0040] S' 10min,230℃ / S' MAX,230℃ ≥0.9···(2)

[0041] When the formula (1) and the formula (2) are satisfied, the resin composition has excellent heat resistance, that is, high hot strength, specifically, high tensile strength at 150°C.

[0042] S' 10min,200℃ / S' MAX,200℃ It is preferably 0.92 to 1.0, more preferably 0.95 to 1.0.

[0043] S' 10min,230℃ / S' MAX,230℃ It is preferably 0.92 to 1.0, more preferably 0.95 to 1.0.

[0044] The method of measuring the torque of a rubber kneaded product obtained by kneading rubber and a rubber crosslinking agent at 200° C. or 230° C. for 10 minutes using a vibration type vulcanization tester over time can be carried out based on JIS K6300-2 "Method for obtaining vulcanization characteristics using a vibration type vulcanization tester".

[0045] The resin composition contains a matrix containing resin and a domain containing rubber. That is, the resin composition has a sea-island structure, the sea phase contains resin, and the island phase contains rubber. The resin composition has a sea-island structure, and thus becomes a material having the thermoplasticity of resin and the softness of rubber.

[0046] The resin constituting the matrix is ​​not limited, and examples thereof include polyolefin resins, polyamide resins, polyester resins, ethylene-vinyl alcohol copolymers, etc. Among them, a preferred resin is a polyolefin resin. Examples of the polyolefin resin include polyethylene, polypropylene, copolymers of ethylene and α-olefins, copolymers of propylene and other α-olefins, etc.

[0047] The resin constituting the matrix more preferably contains a silane-modified resin. When the matrix contains a silane-modified resin, heat resistance is improved.

[0048] Silane-modified resin refers to a resin modified by a silane compound. The silane-modified resin is preferably a resin obtained by modifying a polyolefin-based thermoplastic resin with a silane compound, and more preferably a cross-linked resin having a hydrolyzable silyl group (preferably an alkoxysilyl group) obtained by modifying a polyolefin-based thermoplastic resin with a silane compound or a cross-linked resin obtained by cross-linking the cross-linked resin. In other words, the silane-modified resin is preferably a silane-modified polyolefin resin.

[0049] The silane compound is not limited, but is preferably a compound represented by formula (3).

[0050] R 1 -SiR 2 n Y 3-n ···(3)

[0051] Among them, R 1 is an olefinic (ethylenically) unsaturated hydrocarbon group, R 2 is a hydrocarbon group, Y is a hydrolyzable organic group, and n is an integer of 0 to 2.

[0052] R 1 It is preferably an ethylenically unsaturated hydrocarbon group having 2 to 10 carbon atoms, and examples thereof include a vinyl group, a propenyl group, a butenyl group, a cyclohexenyl group, and a γ-(meth)acryloyloxypropyl group.

[0053] R 2 It is preferably a hydrocarbon group having 1 to 10 carbon atoms, and examples thereof include methyl group, ethyl group, propyl group, decyl group, and phenyl group.

[0054] Y is preferably a hydrolyzable organic group having 1 to 10 carbon atoms, and examples thereof include alkoxy groups (methoxy groups, ethoxy groups, etc.), formyloxy groups, acetoxy groups, propionyloxy groups, alkylamino groups, and arylamino groups.

[0055] Specific examples of the silane compound include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, and γ-methacryloxypropyltrimethoxysilane. Among them, vinyltrimethoxysilane is preferred.

[0056] The polyolefin-based thermoplastic resin constituting the silane-modified resin is not limited, and examples thereof include polyethylene, copolymers of ethylene and α-olefin, polypropylene, copolymers of propylene and other α-olefins, etc. Polypropylene and copolymers of propylene and other α-olefins are preferred, and polypropylene is particularly preferred.

[0057] The hydrolyzable silyl group is a group that generates a silanol group (≡Si—OH) by hydrolysis, and is preferably a group represented by the formula (4).

[0058] -SiR 2 n Y 3-n ···(4)

[0059] Among them, R 2 and Y as described above.

[0060] The crosslinkable resin refers to a resin that is capable of undergoing a crosslinking reaction but has not yet been crosslinked. The type of the crosslinking reaction is not limited, and crosslinking using a peroxide may be used, and crosslinking using moisture (water crosslinking) is preferred.

[0061] The method for modification with silane compounds is not limited, and grafting or copolymerization can be cited. Grafting is a method of adding a silane compound to a resin by a grafting reaction, more specifically, a reaction in which a carbon-hydrogen bond of a polyolefin is cleaved to generate a carbon radical, and a silane compound having an ethylenically unsaturated hydrocarbon group is added thereto. The modification can preferably be carried out by melt-kneading the resin with a silane compound of formula (3) in the presence of a free radical initiator such as an organic peroxide. Copolymerization can preferably be carried out by free radical copolymerization of the monomer constituting the resin with the silane compound of formula (3).

[0062] The silane-modified resin is preferably silane-modified polypropylene. Silane-modified resins are commercially available, and commercially available products can be used as the silane-modified resin used in the present invention. Examples of commercially available silane-modified resins include "Linklon" (registered trademark) manufactured by Mitsubishi Chemical Corporation.

[0063] The resin constituting the matrix may contain resins other than silane-modified resins. As resins other than silane-modified resins, polyolefin resins, polyamide resins, etc. may be cited. As polyolefin resins, polypropylene may be cited. By containing polypropylene on the basis of silane-modified resins, the viscosity of the resin component is stabilized, thus forming a phase structure that is easy to show strength when hot. In addition, since polypropylene has good water vapor barrier properties, the water vapor barrier properties of the entire composition are good.

[0064] The water vapor permeability of the resin is preferably 3.0 g·mm / (m 2 ·24h) or less, more preferably 2.5g·mm / (m 2 ·24h) or less, more preferably 2.0g·mm / (m 2 When the water vapor permeability of the resin is within the above numerical range, water vapor can be prevented from penetrating from the outside when the hose body is formed.

[0065] The content of the resin is 10 to 150 parts by mass, preferably 10 to 100 parts by mass, and more preferably 10 to 80 parts by mass based on 100 parts by mass of the rubber. If the content of the resin is too small, extrusion processability deteriorates, and if it is too large, flexibility cannot be ensured.

[0066] Regarding the rubber constituting the domain, as long as S' 10min,200℃ There is no limitation as long as it is 3.0 dN·m or more and satisfies the equations (1) and (2).

[0067] The rubber constituting the domain is preferably a rubber having a polyisobutylene skeleton.

[0068] The rubber having a polyisobutylene skeleton is not limited as long as it has a polyisobutylene skeleton, but is preferably butyl rubber (IIR), modified butyl rubber, brominated isobutylene-p-methylstyrene copolymer rubber, or styrene-isobutylene-styrene block copolymer, and more preferably butyl rubber or modified butyl rubber.

[0069] The polyisobutylene skeleton refers to the chemical structure formed by the polymerization of multiple isobutylenes, namely -[-CH 2 -C(CH 3 ) 2 -] n - (wherein n is an integer greater than or equal to 2).

[0070] Butyl rubber refers to an isobutylene-isoprene copolymer obtained by copolymerizing isobutylene with a small amount of isoprene, and is abbreviated as IIR. Specific examples of butyl rubber include butyl rubber "Exxon Butyl" 268 manufactured by ExxonMobil Chemical Company.

[0071] Modified butyl rubber refers to butyl rubber having double bonds and halogens in the isoprene skeleton. The modified butyl rubber is preferably halogenated butyl rubber, more preferably brominated butyl rubber or chlorinated butyl rubber, and still more preferably brominated butyl rubber.

[0072] Styrene-isobutylene-styrene copolymer is referred to as SIBS.

[0073] By using a rubber having a polyisobutylene skeleton, the water vapor barrier property of the resin composition is improved.

[0074] The rubber having a polyisobutylene skeleton is preferably dynamically crosslinked. Dynamic crosslinking improves durability.

[0075] The water vapor permeability of the rubber is preferably 3.0 g·mm / (m 2 ·24h) or less, more preferably 2.5 to g·mm / (m 2 ·24h) or less, more preferably 2.0~g·mm / (m 2 · 24h) or less. When the water vapor permeability through the rubber is within the above numerical range, the water vapor barrier property of the resin composition is improved.

[0076] The resin composition contains a rubber cross-linking agent.

[0077] Rubber crosslinking agent as long as S' 10min,200℃ The material that is 3.0 dN·m or more and satisfies the formula (1) and the formula (2) is not particularly limited, and examples thereof include zinc white and alkylphenol formaldehyde resins.

[0078] The rubber crosslinking agent preferably contains zinc white and an alkylphenol formaldehyde resin. When the rubber crosslinking agent contains zinc white and an alkylphenol formaldehyde resin, heat resistance to an environment of 150° C. can be imparted to the resin composition.

[0079] Zinc white refers to zinc oxide, which is an oxide of zinc represented by the chemical formula ZnO. Zinc white is available on the market, and commercially available products can be used in the present invention. Examples of commercially available products include three types of zinc oxide manufactured by Shodo Chemical Industry Co., Ltd.

[0080] The alkylphenol formaldehyde resin refers to a compound represented by formula (5).

[0081]

[0082] In formula (5), X is a hydroxyl group or a halogen, Y and Y' are hydrogen or an alkyl group, Z is an alkyl group or a halogen, and n is an integer of 0 to 20. The halogen constituting X and Z is preferably fluorine, chlorine, bromine or iodine, more preferably bromine. The alkyl group constituting Y, Y' and Z is preferably an alkyl group having 1 to 8 carbon atoms.

[0083] The structural formula represented by formula (5) is a straight chain, but the alkylphenol formaldehyde resin can be synthesized according to a conventional method to have a branched part.

[0084] When X is bromine, it is called brominated alkylphenol formaldehyde resin.

[0085] Alkylphenol formaldehyde resins are commercially available, and commercially available products can be used in the present invention. Examples of commercially available products include alkylphenol-formaldehyde resin "Hitanol" (registered trademark) 2501Y manufactured by Hitachi Chemical Co., Ltd.

[0086] The content of the rubber crosslinking agent is 2.5 to 25 parts by mass, preferably 2.5 to 20 parts by mass, and more preferably 2.5 to 18 parts by mass, based on 100 parts by mass of the rubber. If the content of the rubber crosslinking agent is too small, the dynamic crosslinking of the elastomer is insufficient, and the heat strength is reduced. If it is too large, the resin as the sea phase is affected, and the heat strength is reduced.

[0087] The content of zinc white is 1 to 10 parts by mass, preferably 2 to 8 parts by mass, and more preferably 3 to 8 parts by mass, based on 100 parts by mass of rubber. If the content of zinc white is too small, the dynamic crosslinking of the elastomer is insufficient, and the heat strength is reduced. If it is too large, the resin as the sea phase is affected, and the heat strength is reduced.

[0088] The content of the alkylphenol formaldehyde resin is 1.5 to 15 parts by mass, preferably 1.5 to 10 parts by mass, and more preferably 2 to 10 parts by mass, based on 100 parts by mass of the rubber. If the content of the alkylphenol formaldehyde resin is too small, the dynamic crosslinking of the elastomer is insufficient, and the heat strength is reduced. If it is too large, the resin as the sea phase is affected, and the heat strength is reduced.

[0089] When the resin contains a silane-modified resin, the resin composition preferably contains a silanol condensation catalyst. The silane-modified resin is crosslinked when the resin composition is in contact with water or water vapor, and the crosslinking of the silane-modified resin is promoted by containing the silanol condensation catalyst.

[0090] The silanol condensation catalyst is not limited, and examples thereof include metal organic acid salts, titanic acid esters, borates, organic amines, ammonium salts, phosphonium salts, inorganic acids, organic acids, inorganic acid esters, and bismuth compounds.

[0091] Examples of the metal organic acid salt include, but are not limited to, dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin diacetate, dibutyltin dioctoate, stannous acetate, stannous octoate, cobalt naphthenate, lead octoate, lead naphthenate, zinc octanoate, zinc caprylate, iron 2-ethylhexanoate, iron octoate, and iron stearate.

[0092] The titanate is not limited, and examples thereof include tetrabutyl titanate, tetranonyl titanate, and bis(acetoacetonitrile) diisopropyl titanate.

[0093] The organic amine is not limited, and examples thereof include ethylamine, dibutylamine, hexylamine, triethanolamine, dimethylsoyamine, tetramethylguanidine, and pyridine.

[0094] The ammonium salt is not limited, and examples thereof include ammonium carbonate and tetramethylammonium hydroxide.

[0095] The phosphonium salt is not limited, and examples thereof include tetramethylphosphonium hydroxide and the like.

[0096] The inorganic acid is not limited, and examples thereof include sulfuric acid and hydrochloric acid.

[0097] The organic acid is not limited, and examples thereof include sulfonic acids such as acetic acid, stearic acid, maleic acid, toluenesulfonic acid, and alkylnaphthalenesulfonic acid. The inorganic acid ester is not limited, and examples thereof include phosphoric acid ester.

[0098] The bismuth compound is not limited, and organic bismuth such as bismuth 2-ethylhexanoate may be mentioned.

[0099] The silanol condensation catalyst is preferably a metal organic acid salt, a sulfonic acid, or a phosphoric acid ester, and more preferably a tin metal carboxylate, such as dioctyltin dilaurate, alkylnaphthalenesulfonic acid, or ethylhexyl phosphate. In addition, the silanol condensation catalyst may be used alone or in combination of two or more.

[0100] The content of the silanol condensation catalyst is preferably 0.0001 to 0.5 parts by mass, more preferably 0.0001 to 0.3 parts by mass, based on 100 parts by mass of the silane-modified resin.

[0101] In addition, the silanol condensation catalyst is preferably used as a silanol condensation catalyst-containing masterbatch containing a resin and a silanol condensation catalyst. Resins that can be used in the silanol condensation catalyst-containing masterbatch include polyolefins, preferably polyethylene, polypropylene, and copolymers thereof.

[0102] When the silanol condensation catalyst is used as a silanol condensation catalyst-containing masterbatch containing a resin and a silanol condensation catalyst, the content of the silanol condensation catalyst in the masterbatch is not limited, but is preferably 0.1 to 5.0% by mass. In addition, a commercially available masterbatch containing a silanol condensation catalyst can be used, for example, "PZ010" manufactured by Mitsubishi Chemical Corporation can be used.

[0103] The resin composition preferably contains an antioxidant. By containing an antioxidant, extrusion moldability is stabilized.

[0104] As the anti-aging agent, there is no limitation, and examples thereof include hindered phenol antioxidants, phenol antioxidants, amine antioxidants, phosphorus heat stabilizers, metal deactivators, sulfur heat stabilizers, etc., preferably hindered phenol antioxidants, more preferably hindered phenol antioxidants containing a pentaerythritol ester structure. As a specific example of the hindered phenol antioxidant, IRGANOX (registered trademark) 1010 (pentaerythritol tetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate]) manufactured by BASF Japan Co., Ltd. can be cited.

[0105] The content of the antioxidant is preferably 1 to 10 parts by mass, more preferably 2 to 8 parts by mass, and even more preferably 3 to 7 parts by mass, based on 100 parts by mass of the rubber.

[0106] Tensile strength TB of the resin composition at 150°C 150 In order to make the tensile strength TB of the resin composition at 150°C 150 Within the above numerical range, the degree of crosslinking of the rubber is important.

[0107] The water vapor permeability of the resin composition is preferably 3.0 g·mm / (m 2·24h) or less, more preferably 2.5g·mm / (m 2 ·24h) or less, more preferably 2.0g·mm / (m 2 In order to make the water vapor permeability of the resin composition within the above numerical range, a rubber and a resin with a low water vapor permeability are used.

[0108] The 10% modulus M10 of the resin composition at room temperature is preferably 10 MPa or less, more preferably 0.2 to 9 MPa, and further preferably 0.4 to 8 MPa. In order to make the 10% modulus M10 of the resin composition at room temperature within the above numerical range, the ratio of the rubber amount in the resin composition can be mentioned.

[0109] The present invention (II) relates to a method for producing a resin composition containing a matrix containing a resin and a structural domain containing a rubber. The method for producing the resin composition (II) is characterized in that it comprises melt-kneading a resin, a rubber and a rubber crosslinking agent, and measuring the torque of a rubber mixture kneaded with the rubber and the rubber crosslinking agent when heated at 200°C and 230°C for 10 minutes using a vibration vulcanization tester over time, and the torque S' after 10 minutes at 200°C is 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.9.

[0110] The melt kneading is not limited and can be carried out using a kneader, a single-screw or double-screw kneading extruder, or the like.

[0111] The temperature for melt kneading is not limited as long as melt kneading can be performed, but is preferably 170 to 240°C.

[0112] The melt-kneading time is not limited as long as the target kneaded product can be prepared, but is preferably 2 to 10 minutes.

[0113] Melt kneading is performed by placing resin, rubber, a rubber crosslinking agent, and various additives such as an antioxidant as needed into a kneading machine or the like.

[0114] However, when resin contains silane-modified resin and resin combination contains silanol condensation catalyst, preferably silanol condensation catalyst is not added in the process of melt mixing. When silanol condensation catalyst is added in the process of melt mixing, when the crosslinked resin combination of the structural domain modulated in the process of melt mixing contacts with the water vapor in the atmosphere, the silane-modified resin in the resin combination is gradually crosslinked, and the crosslinked resin combination becomes difficult to shape. Therefore, silanol condensation catalyst is preferably added to the crosslinked resin combination of the structural domain when shaping.

[0115] The present invention (III) relates to a hose for transporting a refrigerant. The hose for transporting a refrigerant of the present invention (III) comprises an inner layer, a reinforcing layer and an outer layer, and the outer layer contains the resin composition of the present invention (I). The outer layer contains the resin composition of the present invention (I), so that the hose has excellent heat resistance and water vapor barrier properties.

[0116] A cross-sectional view of one embodiment of a refrigerant transport hose is shown in FIG. Figure 1 The refrigerant transport hose 1 includes an inner layer 2 , a reinforcement layer 3 disposed outside the inner layer 2 , and an outer layer 4 disposed outside the reinforcement layer 3 .

[0117] The inner layer is not limited and may be formed of rubber, a thermoplastic elastomer, a thermoplastic resin composition having a sea-island structure, or the like.

[0118] There is no limitation on the reinforcing layer, and it may be a woven fiber layer, for example.

[0119] The reinforcing layer is not limited, but preferably contains polyester fiber, polyamide fiber, aramid fiber, PBO fiber, vinylon fiber or rayon fiber.

[0120] The method for manufacturing the refrigerant transport hose is not particularly limited, and the hose can be manufactured as follows: First, an inner layer is extruded into a tube by extrusion molding, fibers as a reinforcement layer are braided on the tube, and an outer layer is coated on the fibers by extrusion molding.

[0121] Example

[0122] [raw materials]

[0123] The raw materials used in the following Examples and Comparative Examples are as follows.

[0124] IIR: ExxonMobil Chemical Company butyl rubber "Exxon Butyl" 268 (water vapor transmission rate: 1.5g mm / (m 2 ·24h))

[0125] Br-IIR: Exxon Mobil Chemical Company's bromobutyl rubber "Exxon Bromobutyl" 2255 (water vapor transmission rate: 1.6g·mm / (m 2 ·24h))

[0126] BIMS: ExxonMobil Chemical Company's brominated isobutylene-p-methylstyrene copolymer rubber "EXXPRO" (registered trademark) 3745 (water vapor transmission rate: 1.4 g·mm / (m 2 ·24h))

[0127] Rubber crosslinking agent-1: Zinc oxide 3 types (zinc white) manufactured by Shodo Chemical Industry Co., Ltd.

[0128] Rubber crosslinking agent-2: Alkylphenol formaldehyde resin "Hitanol" (registered trademark) 2501Y manufactured by Hitachi Chemical Co., Ltd.

[0129] Rubber crosslinking agent-3: Brominated alkylphenol formaldehyde resin "Tackirol" (registered trademark) 250-I manufactured by Taoka Chemical Industry Co., Ltd.

[0130] Nocceler TT: Vulcanization accelerator "Nocceler" (registered trademark) TT manufactured by Ouchi Shinko Chemical Industry Co., Ltd., substance name: Tetramethylthiuram disulfide

[0131] Silane-modified resin: Silane-modified polypropylene "Linklon" (registered trademark) XPM800HM manufactured by Mitsubishi Chemical Corporation (water vapor transmission rate: 1.5 g·mm / (m 2 ·24h))

[0132] PP: Prime Polymer Co., Ltd. propylene homopolymer "Prime Polymer" (registered trademark) J108M (water vapor transmission rate: 1.5 g·mm / (m 2 ·24h))

[0133] PA11: Nylon 11 "RILSAN" (registered trademark) BESNO TL manufactured by Arkema (water vapor transmission rate: 5.4 g·mm / (m 2 ·24h))

[0134] PA6: Nylon 6 "UBE Nylon" (registered trademark) 1011FB manufactured by Ube Industries, Ltd. (water vapor transmission rate: 9.2 g·mm / (m 2 ·24h))

[0135] Anti-aging agent-1: Hindered phenol-based anti-aging agent "IRGANOX" (registered trademark) 1010 manufactured by BASF Japan Co., Ltd.

[0136] Anti-aging agent-2: N-phenyl-N'-(1,3-dimethylbutyl)-p-phenylenediamine "SANTOFLEX" (registered trademark) 6PPD manufactured by Solutia

[0137] Silanol condensation catalyst: Mitsubishi Chemical Corporation's silane crosslinking agent masterbatch "Catalyst MB" PZ010

[0138] [Examples 1 to 9 and Comparative Examples 1 to 3]

[0139] The raw materials were fed into a twin-screw kneading extruder (manufactured by Nippon Steel Works, Ltd.) at the mixing ratios shown in Tables 1 to 3, and kneaded for 3 minutes at 235° C. The kneaded product was continuously extruded from the twin-screw kneading extruder into a strand, water-cooled, and cut with a cutter to obtain a pelletized resin composition.

[0140] For each example and comparative example, S' was measured. 10min,200℃ , S' MAX,200℃ , S' 10min,230℃ and S' MAX,230℃ The obtained resin composition was measured for water vapor transmission rate, 10% modulus, and tensile strength at 150° C. The measurement results are shown in Tables 1 to 3.

[0141] In addition, the measurement method of each measurement item is as follows.

[0142] [Measurement of torque]

[0143] The rubber and rubber crosslinking agent were kneaded at 60°C for 5 minutes using a kneading machine such as a kneader or a Banbury mixer. The kneaded unvulcanized rubber mixture was formed into a sheet of 2 to 4 mm by a press at 80°C. Based on JIS K6300-2 "Method for obtaining vulcanization characteristics using a vibration vulcanization tester", a strain shear stress measuring machine (RPA2000 manufactured by α-Technology Co., Ltd.) was used to measure the maximum torque S' of 0 to 10 minutes obtained when the unvulcanized rubber composite pressed sheet was heated at 200°C and 230°C for 10 minutes. MAX,200℃ and S' MAX,230℃ And the torque S' after 10 minutes 10min,200℃ and S' 10min,230℃ .

[0144] [Measurement of water vapor transmission rate]

[0145] A 40mmφ single-screw extruder with a 550mm wide T-die (manufactured by Pla Technology Co., Ltd.) was used. The temperatures of the barrel and the die were set to the melting point of the polymer component with the highest melting point in the sample composition + 10°C. Under the conditions of a cooling roller temperature of 50°C and a pulling speed of 3m / min, the resin composition or resin sample was molded into a sheet with an average thickness of 0.2mm.

[0146] The rubber sample was formed into a 0.5 mm pressed sheet by pressing an unvulcanized rubber composite pressed sheet used for the torque measurement and crosslinking it at 200° C. for 10 minutes.

[0147] The obtained sheet was allowed to stand in air at a temperature of 25°C and a relative humidity of 50% for 72 hours to be crosslinked, and the water vapor transmission rate was measured at a temperature of 60°C and a relative humidity of 95% using a water vapor transmission tester manufactured by GTR Tec Co., Ltd.

[0148] The water vapor permeability is an index of water vapor barrier properties. The smaller the water vapor permeability is, the better the water vapor barrier properties are.

[0149] [Determination of 10% modulus]

[0150] The cross-linked sheet with an average thickness of 0.2 mm produced in the measurement of water vapor transmission rate was punched into a JIS No. 3 dumbbell shape, and a tensile test was carried out at a temperature of 25°C and a speed of 500 mm / min based on the measurement method specified in JIS K6251 "Rubber, vulcanized and thermoplastic rubber - Method for determining tensile properties". The stress at 10% elongation (10% modulus) was calculated from the obtained stress-strain curve.

[0151] The 10% modulus is an index of flexibility. The smaller the 10% modulus, the more excellent the flexibility.

[0152] [Measurement of tensile strength at 150°C]

[0153] The sheet with an average thickness of 0.2 mm produced in the measurement of water vapor transmission rate was left to stand in air at a temperature of 25°C and a relative humidity of 50% for more than 72 hours to produce a sheet of a cross-linked resin composition. The sheet of the cross-linked resin composition was punched into a JIS No. 3 dumbbell shape, and a tensile test was performed at a temperature of 150°C and a speed of 500 mm / min based on the measurement method specified in JIS K6251 "Vulcanized rubber and thermoplastic rubber-Method for determining tensile properties". The stress at break, i.e., the tensile strength TB, was determined from the obtained stress-strain curve. 150 .

[0154] The tensile strength at 150° C. is an indicator of heat resistance. The higher the tensile strength at 150° C., the better the heat resistance.

[0155] [Table 1]

[0156] Table 1

[0157]

[0158] [Table 2]

[0159] Table 2

[0160]

[0161] [Table 3]

[0162] Table 3

[0163]

[0164] Industrial Availability

[0165] The resin composition of the present invention can be suitably used as a material for producing a hose for transporting a refrigerant.

[0166] Description of Reference Numerals

[0167] 1Refrigerant delivery hose

[0168] 2Inner layer

[0169] 3 Strengthening layer

[0170] 4 Outer Layer

Claims

1. A resin composition comprising a matrix containing a resin and a domain containing a rubber, wherein the resin composition contains a rubber crosslinking agent, and when a rubber compound kneaded with rubber and a rubber crosslinking agent is heated at 200° C. and 230° C. for 10 minutes using a vibration vulcanization tester, the torque S′ after 10 minutes at 200° C. is measured over time. 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.

9.

2. The resin composition according to claim 1, wherein the water vapor permeability of the resin is 3.0 g·mm / (m 2 24h) or less.

3. The resin composition according to claim 1 or 2, wherein the water vapor permeability of the rubber is 3.0 g·mm / (m 2 24h) or less. 4 . The resin composition according to claim 1 , wherein the rubber has a polyisobutylene skeleton. 5 . The resin composition according to claim 1 , wherein the rubber crosslinking agent comprises zinc white and an alkylphenol formaldehyde-based resin. 6 . The resin composition according to claim 1 , wherein the resin is a polyolefin resin. 7 . The resin composition according to claim 1 , wherein the resin comprises a silane-modified polyolefin resin.

8. The resin composition according to claim 7, which contains a silanol condensation catalyst. 9 . The resin composition according to claim 1 , wherein the resin composition has a tensile strength at 150° C. of 1.5 MPa or more.

10. The resin composition according to any one of claims 1 to 9, wherein the water vapor permeability of the resin composition is 3.0 g·mm / (m 2 24h) or less. 11 . The resin composition according to claim 1 , wherein a 10% modulus of the resin composition at room temperature is 10 MPa or less.

12. A method for producing a resin composition comprising a matrix containing a resin and a domain containing a rubber, the method comprising melt-kneading a resin, a rubber and a rubber crosslinking agent, and measuring the torque of a rubber mixture kneaded with the rubber and the rubber crosslinking agent when heated at 200° C. and 230° C. for 10 minutes using a vibration vulcanization tester over time, wherein the torque S′ after 10 minutes at 200° C. is 10min,200℃ is 3.0dN·m or more, and S' 10min,200℃ , Torque S' after 10 minutes at 230℃ 10min,230℃ , the maximum torque value S' at 200°C for 0 to 10 minutes MAX,200℃ , and the maximum torque S' at 230°C for 0 to 10 minutes MAX,230℃ The relationship satisfies S' 10min,200℃ / S' MAX,200℃ ≥0.9 and S' 10min,230℃ / S' MAX,230℃ ≥0.

9. 13 . A hose for transporting a refrigerant, comprising an inner layer, a reinforcement layer, and an outer layer, wherein the outer layer comprises the resin composition according to claim 1 .

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