Molding composition, molded article, pore-forming material, and masterbatch for molding

Abstract

To provide a molding composition enabling production of a molded article having internal voids while suppressing decrease in breaking strength and decrease in compression set.SOLUTION: A molding composition comprising the following components (A) and (B): Component (A): a matrix component having thermosetting properties; and Component (B): particles comprising a thermoplastic resin, the particles having a melting point of 70 to 150°C as measured by differential scanning calorimetry (DSC), a melting enthalpy (ΔHm) of 50 to 200 J / g as measured by differential scanning calorimetry (DSC), and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) as measured by differential scanning calorimetry (DSC) of 0.3 to 2.0.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a molding composition, a molded article, a pore-forming material, and a molding masterbatch. [Background technology]

[0002] Molded articles formed from a thermosetting matrix component are used in a wide range of applications, such as housing equipment and electronic components. In particular, when the matrix component is rubber (vulcanized rubber), the resulting molded article has excellent rubber elasticity and heat resistance, and is therefore widely used as automobile tires, anti-vibration rubber, and various sealing materials for automobiles, etc. For example, Patent Document 1 proposes using a chemical foaming agent as a pore-forming material in automobile sealing materials to reduce weight and improve sound insulation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-275302 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when the chemical foaming agent disclosed in the above Patent Document 1 is used, the introduced pores form a continuous structure, and it has been confirmed that the breaking strength and compression set decrease. An object of the present invention is to provide a molding composition that can be used to produce a molded article having internal voids and in which the decrease in breaking strength and compression set is suppressed. [Means for solving the problem]

[0005] As a result of extensive research, the present inventors have found that the above problems can be solved by using a molding composition containing specific components, and have thus completed the present invention. That is, the present invention is a molding composition containing the following component (A) and component (B): Component (A): A thermosetting matrix component Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.0.

[0006] The molding composition of the present invention preferably satisfies any one of the following 1) to 5). 1) The true specific gravity of the component (B) is 0.65 to 1.4. 2) The circularity of the component (B) is 0.70 to 1.0. 3) The thermoplastic resin includes at least one selected from an olefin-based resin and a polyester-based resin. 4) The component (A) is at least one selected from thermosetting resins and rubbers. 5) The content of the component (B) is 1 to 10 parts by weight per 100 parts by weight of the component (A).

[0007] The molded article of the present invention is obtained by molding the above molding composition.

[0008] The pore-forming material of the present invention contains the following component (B). Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.0.

[0009] The molding masterbatch of the present invention contains the following component (B) and component (C). Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.0. Ingredient (C): Base ingredient [Effects of the Invention]

[0010] The molding composition of the present invention can be used to produce a molded article having internal voids and in which the decrease in breaking strength and compression set is suppressed. The molded article of the present invention is obtained by molding the above molding composition, and therefore has internal voids, and the decrease in breaking strength and compression set is suppressed. The pore-forming material of the present invention can produce a molded article having pores therein, in which the decrease in breaking strength and compression set is suppressed. The molding masterbatch of the present invention can produce a molded article having internal voids and in which the decrease in breaking strength and compression set is suppressed. DETAILED DESCRIPTION OF THE INVENTION

[0011] The molding composition of the present invention contains the following component (A) and component (B): Component (A): A thermosetting matrix component Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.0. Each component will be described in detail below.

[0012] [Component (A)] The thermosetting matrix component (A) is a component that forms a molded body after curing, and also makes it possible to maintain the pores introduced into the molded body by component (A). There are no particular restrictions on component (A), but it is preferred that the component (A) is at least one selected from thermosetting resins and rubbers in order to achieve the effects of the present invention.

[0013] The thermosetting resin is not particularly limited, but examples thereof include phenolic resin, urea resin, melamine resin, unsaturated polyester resin, epoxy resin, diallyl phthalate resin, urethane resin, silicon resin, polyimide resin, etc., and one or more of these may be used in combination.

[0014] The phenolic resin is not particularly limited, but examples thereof include novolac type phenolic resins, resol type phenolic resins, benzylic ether type phenolic resins, and the like, and one or more types may be used in combination. The unsaturated polyester resin is not particularly limited, and examples thereof include ortho-unsaturated polyester resin, iso-unsaturated polyester resin, and bisphenol-unsaturated polyester resin, and one or more of these may be used in combination.

[0015] The epoxy resin is not particularly limited, and examples thereof include glycidyl ether-based epoxy resins such as bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, phenol novolac-type epoxy resin, cresol novolac-type epoxy resin, and brominated epoxy resin; alicyclic epoxy resins in which double bonds have been epoxidized, such as butadiene, pentadiene, vinylcyclohexene, and dicyclopentyl ether; polyglycidyl compounds obtained by reacting polyols, hydroxyl group-containing silicone resins, and the like with epihalohydrins; glycidyl amine-based resins such as N,N-diglycidylaniline, tetraglycidyldiaminodiphenylmethane, and triglycidyl-p-aminophenol; and glycidyl ester-based resins such as phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, and diglycidyl-p-oxybenzoic acid, and the like. One or more of these may be used.

[0016] The urethane resin is not particularly limited, but examples thereof include those containing a polyisocyanate compound as a base resin, a polyol compound as a curing agent, a catalyst, etc. The polyisocyanate compound is not particularly limited, but examples thereof include aromatic polyisocyanates, alicyclic polyisocyanates, aliphatic polyisocyanates, etc., and one or more of these may be used in combination.

[0017] When component (A) comprises a thermosetting resin, the molding composition may also comprise a curing agent. The curing agent is not particularly limited, and examples thereof include amine-based curing agents such as polyamidoamine, polyallylamine, dodecamethylenediamine, triglycidyl isocyanate, polyisocyanate, aliphatic amine, aromatic amine, modified amine compound, diacetone acrylamide, and triethylenetetramine; phthalic anhydride, trimellitic anhydride, pyromellic anhydride, benzophenonetetracarboxylic anhydride, ethylene glycol bistrimellitate, glycerol tristrimellitate, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride, methylcyclohexenedicarboxylic anhydride, alkylstyrene-maleic anhydride copolymer, and polyazelaic acid anhydride. organic peroxides such as ketone peroxides, peroxyketals, hydroperoxides, dialkyl hydroxyloxides, diacyl peroxides, peroxydicarbonates, and peroxyesters; inorganic acids such as sulfuric acid and phosphoric acid; organic acids such as benzenesulfonic acid, ethylbenzenesulfonic acid, paratoluenesulfonic acid, xylenesulfonic acid, naphtholsulfonic acid, and phenolsulfonic acid; aromatic polyols such as bisphenol A, bisphenol F, phenol novolac, and cresol novolac; alicyclic polyols such as cyclohexanediol, methylcyclohexanediol, isophoronediol, dicyclohexylmethanediol, and dimethyldicyclohexylmethanediol; and aliphatic polyols such as ethylene glycol, propylene glycol, butanediol, pentanediol, and hexanediol, and these may be used alone or in combination.

[0018] The rubber is not particularly limited, and examples thereof include natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, acrylonitrile butadiene rubber, ethylene-α-olefin copolymer rubber, ethylene-α-olefin-non-conjugated diene copolymer rubber, halogenated ethylene-α-olefin-non-conjugated diene copolymer rubber, sulfonated ethylene-α-olefin-non-conjugated diene copolymer rubber, maleated ethylene-α-olefin-non-conjugated diene copolymer rubber, butyl rubber, isobutylene isoprene rubber, nitrile rubber, hydrogenated nitrile rubber, urethane rubber, silicone rubber, chlorosulfonated polyethylene, chlorinated polyethylene, acrylic rubber, epichlorohydrin rubber, polysulfide rubber, and the like, and one or more of these may be used in combination. The rubber is not particularly limited, but it is preferable to include at least one selected from natural rubber, isoprene rubber, butadiene rubber, and silicone rubber in order to further achieve the effects of the present invention.

[0019] The solubility parameter of the rubber (hereinafter sometimes referred to as the SP value of the rubber) is not particularly limited, but is preferably 6 to 15 (cal / cm 3 ) 1 / 2 , more preferably 8 to 12 (cal / cm 3 ) 1 / 2 When the SP value is within the above range, the dispersibility of component (B) improves, and pores tend to be introduced uniformly into the molded product.

[0020] When component (A) contains rubber, the molding composition may contain a vulcanizing / crosslinking agent, a vulcanization accelerator, or a vulcanization accelerator assistant. The vulcanizing / crosslinking agent is not particularly limited, and examples thereof include sulfur such as powdered sulfur, precipitated sulfur, colloidal sulfur, and insoluble sulfur; inorganic vulcanizing agents such as sulfur chloride, selenium, and tellurium; sulfur-containing organic compounds such as morpholine disulfide, alkylphenol disulfides, thiuram disulfides, and dithiocarbamates; and organic peroxides such as 1,1-di-t-butylperoxy-3,3,5-trimethylcyclohexane, di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, and 1,3-bis-(t-butylperoxy-isopropyl)benzene, and the like. These may be used alone or in combination of two or more.

[0021] The vulcanization accelerator is not particularly limited, and examples thereof include aldehyde ammonias such as hexamethylenetetramine; guanidines such as diphenylguanidine, di(o-tolyl)guanidine, and o-tolyl-piguanide; thioureas such as thiocarbanilide, di(o-tolyl)thiourea, N,N'-diethylthiourea, and dilaurylthiourea; thiazoles such as mercaptobenzothiazole, dibenzothiazole disulfide, and N,N'-di(ethylthiocarbamoylthio)benzothiazole; thiurams such as tetramethylthiuram disulfide, tetraethylthiuram disulfide, and tetrabutylthiuram disulfide; carbamates such as zinc dimethylthiocarbamate, sodium dimethyldithiocarbamate, copper dimethyldithiocarbamate, tellurium dimethylthiocarbamate, and iron dimethylthiocarbamate; and xanthates such as zinc butylthioxanthate, and the like, and these may be used alone or in combination.

[0022] The vulcanization accelerator aid is not particularly limited, but examples thereof include metal oxides such as magnesium oxide and zinc oxide; and organic acids (salts) such as stearic acid, oleic acid, and zinc stearate, and one or more of these may be used in combination.

[0023] The curing initiation temperature of component (A) is not particularly limited, but is preferably 100 to 200° C., more preferably 130 to 180° C. When the curing temperature is within the above range, the timing of melting and curing of the pore-forming material is close, and the pores introduced into the molded body tend to be uniform.

[0024] [Component (B)] Component (B) is a particle containing a thermoplastic resin and has the above-mentioned specific physical properties. Component (B) can introduce voids into the resulting molded article. Component (B) does not have thermal expandability, meaning it expands when heated.

[0025] The thermoplastic resin contained in component (B) is not particularly limited, but examples thereof include polyvinyl resins, polyacrylic resins, polystyrene resins, polyolefin resins, polyester resins, polyether resins, polyamide resins, thermoplastic polyurethane resins, and cellulose resins, and one or more of these may be used in combination. The thermoplastic resin contained in component (B) is preferably at least one selected from olefin-based resins and polyester-based resins, as this resin has high flexibility and can be dispersed uniformly.

[0026] The polyvinyl resin is not particularly limited, but examples thereof include polyvinyl chloride, polyvinyl acetate, polyvinyl alcohol, etc., and one or more of these may be used in combination. The polyacrylic resin is not particularly limited, but examples thereof include poly(meth)acrylic acid esters such as polymethyl methacrylate; poly(meth)acrylic acid ester-acrylic acid copolymers; and the like, and one or more types may be used in combination. In the present invention, (meth)acrylic means acrylic or methacrylic.

[0027] The polystyrene resin is not particularly limited, and examples thereof include polystyrene, poly(meth)acrylate-styrene copolymer, styrene elastomer, etc. These polystyrene resins may be used alone or in combination of two or more. Examples of the polyolefin resin include polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester copolymer, low molecular weight polyolefin, and olefin elastomer, and one or more of these may be used in combination.

[0028] Examples of polyester resins include polycondensates of polyhydric alcohols and polycarboxylic acids, polycondensates of polyhydric alcohols, polycarboxylic acids and hydroxycarboxylic acids, polycondensates of hydroxycarboxylic acids, and polycondensates of their derivatives. The polyester resin is not particularly limited, and examples thereof include polylactic acid, polypropiolactone, polycaprolactone, polycaprolactone butylene succinate, polybutylene adipate caprolactone, polybutylene succinate hydroxycaproate, polybutylene succinate, polybutylene succinate adipate, polybutylene succinate carbonate, polybutylene succinate terephthalate, polybutylene succinate adipate terephthalate, polybutylene succinate lactate, polyethylene terephthalate, polytrimethylene terephthalate, polyethylene terephthalate copolymer, polybutylene adipate terephthalate, polytetramethylene adipate terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, polybutylene adipate, polybutylene Examples of such polyhydroxyalkylene copolymers include polyethylene adipate terephthalate, polyethylene succinate, polyethylene adipate, polyethylene adipate terephthalate, polytetramethylene succinate, polypropylene succinate, polyhydroxyalkanoate, polyhydroxybutyrate, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), polyhydroxybutyrate valerate, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxypropionate), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyacyl), polyhydroxyacyl, polyglycolic acid, lactic acid-glycolic acid copolymer, and polyester elastomers, and these may be used alone or in combination of two or more. The polyester resin is not particularly limited, but examples thereof include aliphatic polyester resins, aromatic polyester resins, aliphatic-aromatic polyester resins, etc. The polyester resin is not particularly limited, but is preferably at least one selected from aliphatic polyester resins and aliphatic-aromatic polyester resins, and more preferably an aliphatic polyester resin, in terms of excellent flexibility.

[0029] The aliphatic polyester resin is not particularly limited as long as the polyhydric alcohol, polycarboxylic acid and hydroxycarboxylic acid constituting the polyester resin are aliphatic polyhydric alcohol, aliphatic polycarboxylic acid and aliphatic hydroxycarboxylic acid, respectively.

[0030] The aliphatic polyhydric alcohol is not particularly limited, and examples thereof include ethylene glycol, 1,3-propanediol, 1,4-butanediol, diethylene glycol, 1,5-pentanediol, 1,6-hexanediol, propylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-butanediol, 2,3-butanediol, neopentyl glycol (2,2-dimethylpropane-1,3-diol), 1,2-hexanediol, 2,5-hexanediol, 2-methyl-2,4-pentanediol, 3-methyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2,2-bis(4-hydroxycyclohexyl)propane, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, trimethylolpropane, glycerin, and pentaerythritol, and may be composed of one or more kinds.

[0031] The aliphatic polycarboxylic acid is not particularly limited, but examples thereof include succinic acid, adipic acid, suberic acid, sebacic acid, azelaic acid, octyl succinic acid, fumaric acid, maleic acid, itaconic acid, decamethylenedicarboxylic acid, and anhydrides thereof, and may be composed of one or more kinds. The aliphatic hydroxycarboxylic acid is not particularly limited, but examples thereof include lactic acid, glycolic acid, hydroxybutyric acid, hydroxycaproic acid, hydroxydimethylbutyric acid, and hydroxymethylbutyric acid, and may be composed of one or more types.

[0032] The aliphatic polyester resin is not particularly limited, and examples thereof include polycaprolactone butylene succinate, polybutylene succinate, polybutylene succinate adipate, polybutylene succinate carbonate, polybutylene adipate, polybutylene succinate lactate, polyethylene succinate, polyethylene adipate, polytetramethylene succinate, polyhydroxyalkanoate, polyhydroxybutyrate, poly(3-hydroxybutyrate), Examples of such polyhydroxybutyrates include poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), polyhydroxybutyrate valerate, poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxypropionate), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyacyl), polyhydroxyacyl, and polylactic acid, and one or more of these may be used in combination.

[0033] The aliphatic-aromatic polyester resin is not particularly limited as long as the polyhydric alcohol, polycarboxylic acid, and hydroxycarboxylic acid, which are the constituent units of the polyester resin, contain an aliphatic polyhydric alcohol, an aliphatic polycarboxylic acid, and an aliphatic hydroxycarboxylic acid, respectively, and further contain an aromatic polycarboxylic acid or a derivative thereof. The aromatic polycarboxylic acid is not particularly limited, but examples thereof include o-phthalic acid, terephthalic acid, isophthalic acid, cyclohexanedicarboxylic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, trimellitic acid, and pyromellitic acid, and may be composed of one or more types.

[0034] The aliphatic-aromatic polyester resin is not particularly limited, but examples thereof include polybutylene succinate terephthalate, polybutylene adipate terephthalate, polytetramethylene adipate terephthalate, polybutylene succinate adipate terephthalate, and the like, and one or more of these may be used in combination.

[0035] The polyether resin is not particularly limited, but examples thereof include polyphenylene ether, polysulfone, polyethersulfone, polyacetal, polyetherketone, polyetheretherketone, and the like, and one or more of these may be used in combination.

[0036] The polyamide resin is not particularly limited, but examples thereof include nylon 1, nylon 3, nylon 4, polycaproamide (nylon 6), poly-ω-aminoheptanoic acid (nylon 7), poly-9-aminononanoic acid (nylon 9), polyundecaneamide (nylon 11), polylaurin lactam (nylon 12), polyethylenediamineadipamide (nylon 2,6), polytetramethyleneadipamide (nylon 4,6), polyhexamethylenediadipamide ( Examples include poly(ethylene glycol) copolymer (nylon 6,6), polyhexamethylene sebacamide (nylon 6,10), polyhexamethylene dodecamide (nylon 6,12), polyoctamethylene adipamide (nylon 8,6), polydecamethylene adipamide (nylon 10,6), polydecamethylene sebacamide (nylon 10,10), polydodecamethylene dodecamide (nylon 12,12), and metaxylenediamine-6 ​​nylon (MXD6), and one or more of these may be used in combination.

[0037] The thermoplastic polyurethane resin is not particularly limited, but examples thereof include polyester polyurethane resin, polyether polyurethane resin, polycarbonate polyurethane resin, etc., and one or more of these may be used in combination. The cellulose-based resin is not particularly limited, but examples thereof include cellulose acetate, ethyl cellulose, cellulose ether derivatives, cellulose acetate propionate, cellulose acetate butyrate, and the like, and one or more of these may be used in combination.

[0038] The melting point of the thermoplastic resin is not particularly limited, but is preferably 70 to 150° C., more preferably 80 to 140° C., and even more preferably 80 to 120° C. If the melting point is 70° C. or higher, the stability of component (B) during production of the molded article composition tends to be improved. If the melting point is 150° C. or lower, pores tend to be introduced more efficiently into the obtained molded article.

[0039] The thermoplastic resin is the main component of component (B) and is preferably one that forms particles of component (B). The weight percentage of the thermoplastic resin in component (B) is not particularly limited, but is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, even more preferably 80 to 99.995% by weight, and particularly preferably 90 to 99.99% by weight. If the weight percentage is 50% by weight or more, pores tend to be introduced more efficiently into the obtained molded article. Component (B) may be particles having internal voids or particles made of a thermoplastic resin. In terms of achieving the effects of the present invention, component (B) is preferably particles made of a thermoplastic resin.

[0040] In addition to the thermoplastic resin, component (B) may contain a thermosetting resin, cellulose, organic polymers other than these, surfactants, organic substances other than organic polymers, and inorganic substances. The thermosetting resin is not particularly limited, but examples thereof include polyurethane resins, silicone resins, phenolic resins, unsaturated polyester resins, epoxy resins, melamine resins, and rubber, and one or more of these may be used in combination.

[0041] The organic polymer other than thermoplastic resins, thermosetting resins, and cellulose is not particularly limited, and examples thereof include paraffins such as liquid paraffin; silicone oils such as dimethyl silicone; polyalkylene oxides such as polyethylene oxide and polypropylene oxide; and water-soluble polymers such as sodium polyacrylate, polyvinylpyrrolidone, polyvinyl alcohol, dextrin, sodium alginate, potassium alginate, gum arabic, tamarind gum, pectin, pullulan, casein, xanthan gum, carrageenan, tragacanth gum, gelatin, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, carboxymethyl cellulose, and carboxyethyl cellulose, and the like, and one or more of these may be used in combination.

[0042] The surfactant is not particularly limited, and examples thereof include anionic surfactants such as alkyl sulfates, alkyl ether carboxylates, alkyl ether sulfates, alkyl phosphates, polyoxyalkylene alkyl ether acetates, alkyl sulfonates, alkylbenzene sulfonates, polyoxyalkylene alkyl ether sulfates, polyoxyalkylene alkyl ether phosphates, higher fatty acid amide sulfonates, fatty acid alkali metal salts (e.g., potassium laurate, sodium myristate, sodium stearate), alkyl sulfosuccinate ester salts, and N-acylamino acid salts; cationic surfactants such as quaternary ammonium salts and alkylamine salts; polyoxyalkylene oxide-added alkyl ethers, and polyoxyalkylene styrenated phenyl ethers. nonionic surfactants such as esters, ester compounds of polyhydric alcohols and monovalent fatty acids, polyoxyalkylene alkylphenyl ethers, polyoxyalkylene fatty acid esters, polyoxyalkylene sorbitan fatty acid esters, glycerin fatty acid esters, polyoxyalkylene castor oil, polyoxyalkylene hydrogenated castor oil, higher fatty acid PEG glyceryls, higher fatty acid sorbitans, polyoxyalkylene sorbitol fatty acid esters, polyglycerin fatty acid esters, alkyl glycerin ethers, polyoxyalkylene cholesteryl ethers, alkyl polyglucosides, sucrose fatty acid esters, and polysorbates; amphoteric surfactants such as amino acid-based surfactants, betaine-type surfactants, hydrogenated lecithin, and lecithin; and silicone-based surfactants such as modified silicones, and the like may be used alone or in combination of two or more thereof.

[0043] The organic substance other than the organic polymer is not particularly limited, and examples thereof include waxes such as carnauba wax, candelilla wax, beeswax, and higher alcohols; oils such as almond oil, olive oil, rice bran oil, squalane, mineral oil, alkanes, and alkyl benzoates; fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, and cerotic acid; calcium laurate, zinc laurate, zinc myristic acid, zinc palmitate, magnesium stearate, zinc stearate, calcium stearate, aluminum stearate, calcium 12-hydroxystearate, and zinc 12-hydroxystearate. Examples include fatty acid metal salts such as magnesium 12-hydroxystearate, aluminum 12-hydroxystearate, calcium behenate, zinc behenate, magnesium behenate, calcium montanate, zinc montanate, magnesium montanate, and aluminum montanate; and amino acid compounds such as N-lauroyl-L-arginine, N-lauroyl-L-lysine, N-hexanoyl-L-lysine, N-oleyl-L-lysine, N-palmitoyl-L-lysine, N-stearoyl-L-lysine, N-hexanoyl-L-lysine, N-myristonoyl-L-lysine, N-capryloyl-L-lysine, and N-decanoyl-L-lysine, and these may be used alone or in combination of two or more.

[0044] The inorganic substance is not particularly limited, and examples thereof include wollastonite, sericite, kaolin, mica, clay, talc, bentonite, smectite, alumina silicate, pyrophyllite, montmorillonite, calcium silicate, calcium carbonate, magnesium carbonate, dolomite, calcium sulfate, boron nitride, silicon carbide, magnesium silicate, calcium silicate, magnesium aluminometasilicate, magnesium aluminosilicate, hydroxyapatite, titanium oxide, silica, alumina, mica, titanium dioxide, zinc oxide, magnesium oxide, zinc oxide, hydrosaltite, boron nitride, and the like, and one or more of these may be used in combination.

[0045] It is preferable that the component (B) further contains at least one selected from a water-soluble polymer and a surfactant. The weight proportion of at least one selected from the group consisting of water-soluble polymers and surfactants in component (B) is not particularly limited, but is preferably 0 to 50% by weight, more preferably 0.005 to 30% by weight, even more preferably 0.01 to 20% by weight, and particularly preferably 0.02 to 10% by weight.

[0046] Component (B) is a particle having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.0. It is believed that component (B) containing specific components and having the above-described physical properties melts component (B) when component (A) hardens, and the melted component (B) does not recrystallize, allowing voids to be introduced into the interior of the resulting molded body.

[0047] The particles of component (B) have a melting point of 70 to 150°C as measured by a differential scanning calorimeter (DSC). If the melting point is lower than 70°C, the shape stability of the particles during production of the molding composition decreases. If the melting point is higher than 150°C, the particles do not melt during curing of component (A). The melting point is preferably 75 to 150°C, more preferably 80 to 140°C, and even more preferably 80 to 120°C.

[0048] The particles of component (B) have a melting enthalpy (ΔHm) of 50 to 200 J / g as measured by a differential scanning calorimeter (DSC). If the ΔHm is less than 50 J / g, the particles melt too quickly, failing to introduce uniform pores into the resulting molded article, resulting in a decrease in breaking strength. If the ΔHm is more than 200 J / g, the particles melt too slowly, failing to introduce uniform pores into the resulting molded article. The ΔHm is preferably 60 to 180 J / g, more preferably 70 to 150 J / g, and even more preferably 80 to 120 J / g.

[0049] The ratio (ΔHm / ΔHc) of ΔHm to the crystallization enthalpy (ΔHc) measured by differential scanning calorimetry (DSC) of the particles of component (B) is 0.3 to 2.0. If ΔHm / ΔHc is less than 0.3, heat absorption is large and uniform pores cannot be introduced into the obtained molded body. If ΔHm / ΔHc is more than 2.0, crystallization proceeds too quickly, making it impossible to introduce uniform pores into the obtained molded body. ΔHm / ΔHc is preferably 0.5 to 1.8, more preferably 0.7 to 1.5, and particularly preferably 1.0 to 1.4.

[0050] The true specific gravity of the particles that are component (B) is not particularly limited, but is preferably 0.65 to 1.4, more preferably 0.8 to 1.4, and even more preferably 1.0 to 1.4. When the true specific gravity is within the above range, the dispersibility of component (B) tends to be improved. The true specific gravity of component (B) is measured by the method described in the examples.

[0051] The circularity of the particles of component (B) is not particularly limited, but is preferably 0.70 to 1.0, more preferably 0.75 to 1.0, even more preferably 0.80 to 0.95, and particularly preferably 0.85 to 0.95. When the circularity is 0.70 or more, the introduced pores tend to be uniform, and a decrease in breaking strength tends to be suppressed. The circularity of component (B) is measured by the method described in the examples.

[0052] The average particle size of the particles of component (B) is not particularly limited, but is preferably 1 to 100 μm, more preferably 2 to 50 μm, and even more preferably 4 to 30 μm. When the average particle size is within the above range, a decrease in breaking strength tends to be suppressed. The average particle size of component (B) is measured by the method described in the examples.

[0053] The particles of component (B) can be produced, for example, by a method including step 1 of mixing the components constituting component (B), a surfactant, a water-soluble polymer, and water to obtain a pre-mixed liquid; step 2 of heating and stirring the pre-mixed liquid obtained in step 1 to obtain a heated dispersion; and step 3 of cooling the heated dispersion obtained in step 2.

[0054] The manufacturing method for component (B) is preferably one that does not use organic solvents, as this allows for the production of highly dispersible particles. By producing particles in water without using organic solvents, surfactants and water-soluble polymers are more likely to exist at the interface between the particles and water during particle formation, which is thought to contribute to improving the surface properties of the particles.

[0055] The components constituting component (B) can be those described above. It is preferable to mix a surfactant into component (B) during production, as this will allow for the production of highly dispersible particles. The surfactants listed above can be used. The surfactant is not particularly limited, but in terms of achieving the effects of the present invention, it is preferable to use a nonionic surfactant and / or anionic surfactant, since highly dispersible particles can be produced. In particular, it is preferable to use a nonionic surfactant with an HLB value of 1 to 13, since highly dispersible particles can be produced. The HLB value is more preferably 1 to 11, even more preferably 1 to 10, and particularly preferably 1.5 to 10. The HLB value can be calculated, for example, by the following Griffin method formula (1). HLB = 20 × (molecular weight of hydrophilic group / total molecular weight) (1)

[0056] The surfactant may be ultimately contained in the particles, and it is believed that the presence of the surfactant near the particle surface improves dispersibility. The weight proportion of the surfactant in component (B) is not particularly limited, but is preferably 0 to 50% by weight, more preferably 0.001 to 10% by weight, even more preferably 0.005 to 7% by weight, and particularly preferably 0.01 to 3% by weight.

[0057] When a water-soluble polymer is mixed into component (B) during production, highly dispersible particles can be produced, which is preferable. The water-soluble polymer can be any of those listed above. The water-soluble polymer may be finally contained in the particles, and the presence of the water-soluble polymer in the particles is thought to improve dispersibility. The weight proportion of the water-soluble polymer in component (B) is not particularly limited, but is preferably 0 to 50% by weight, more preferably 0.001 to 10% by weight, even more preferably 0.002 to 8% by weight, and particularly preferably 0.005 to 5% by weight.

[0058] The water-soluble polymer is not particularly limited, but may be selected depending on the particle size of the target particles. From the viewpoint of ease of handling, it is preferable that the viscosity of a 4 wt% aqueous solution at 20°C be 2 to 200,000 mPa·s.

[0059] When component (B) is mixed with a surfactant and a water-soluble polymer during production, the water-soluble polymer improves the liquid viscosity during production, and the surfactant improves the efficiency of particle homogenization, thereby reducing the roughness of the particle surface and making it preferable for producing highly dispersible particles. When the particles contain a surfactant and a water-soluble polymer, the weight proportions of the surfactant and the water-soluble polymer in the particles are preferably within the above ranges.

[0060] (Process 1) Step 1 is a step of mixing a thermoplastic resin constituting the particles, which are component (B), a surfactant, a water-soluble polymer, and water to obtain a preliminary mixed liquid.

[0061] In step 1, the total mixing ratio of the thermoplastic resin and surfactant that constitute the particles is not particularly limited, but is preferably 1 to 200 parts by weight, more preferably 3 to 180 parts by weight, even more preferably 5 to 160 parts by weight, and most preferably 10 to 150 parts by weight, relative to 100 parts by weight of water. When the mixing ratio is within the above range, particles with a uniform shape tend to be obtained.

[0062] In step 1, the mixing ratio of the surfactant is not particularly limited, but is preferably 0.001 to 10 parts by weight, more preferably 0.01 to 7 parts by weight, even more preferably 0.05 to 5 parts by weight, and particularly preferably 0.1 to 3 parts by weight, relative to 100 parts by weight of the thermoplastic resin. When the mixing ratio is within the above range, dispersibility tends to be improved.

[0063] In step 1, the mixing ratio of the water-soluble polymer is not particularly limited, but is preferably 0.1 to 100 parts by weight, more preferably 0.5 to 80 parts by weight, even more preferably 1 to 70 parts by weight, and most preferably 2 to 60 parts by weight, relative to 100 parts by weight of water. When the mixing ratio is within the above range, dispersibility tends to be improved.

[0064] (Process 2) Step 2 is a step of heating and stirring the preliminary mixture obtained in step 1 to obtain a heated dispersion. The stirring method is not particularly limited, as long as the mixture is stirred to an extent that it is mixed.

[0065] Heating and stirring under pressure is preferred because particles of uniform shape are more likely to be obtained. The pressure during heating and stirring is not particularly limited, but is preferably equal to or higher than the saturated vapor pressure of water at the temperature during heating, and is preferably 0.1 to 10 MPa.

[0066] The heating temperature is not particularly limited, but is preferably equal to or higher than the melting point of the thermoplastic resin, more preferably at least 5° C. higher, even more preferably at least 10° C. higher, and particularly preferably at least 15° C. In addition, the heating temperature is not particularly limited, but is preferably 80 to 300° C., since particles of a uniform shape are easily obtained.

[0067] The heating time is not particularly limited, but is preferably 1 to 30 hours, more preferably 2 to 25 hours, even more preferably 3 to 20 hours, and particularly preferably 5 to 15 hours. When the heating time is within the above range, particles with a uniform shape tend to be obtained.

[0068] (Step 3) Step 3 is a step of cooling the heated dispersion obtained in step 2. By cooling the heated dispersion in step 2, a dispersion of component (B) can be obtained. The cooling method is not particularly limited, but it is preferable to cool the heated dispersion liquid in step 2 to 5 to 50°C. The cooling rate is not particularly limited, and may be rapid cooling using cooling equipment or natural cooling using air cooling. The stirring method in step 3 is not particularly limited, but stirring may be carried out at the stirring speed of step 2, or stirring may be stopped.

[0069] Component (B) can be obtained, for example, by dehydrating the aqueous dispersion obtained in step 3 using a centrifuge, a pressure press, a vacuum dehydrator, or the like to obtain a wet powder of component (B), and then drying the powder using a tray dryer, an indirect heating dryer, a fluidized bed dryer, a vacuum dryer, a vibration dryer, a flash dryer, etc. The dried product may be further classified by flash classification, screen classification, or the like. Although not particularly limited, measures to reduce the liquid viscosity may be taken as necessary for the aqueous dispersion obtained in step 3. Examples of methods for reducing the liquid viscosity include a method of diluting the aqueous dispersion by adding water, a method of salting out the water-soluble components, and a method of decomposing the water-soluble components with an oxidizing agent or an enzyme.

[0070] (pore forming material) As described above, component (B) is capable of introducing pores into a molded article and can be used as a component for forming a pore-forming material. The pore-forming material is suitable for use with a thermosetting matrix component, more suitable for use with at least one selected from thermosetting resins and rubbers, and particularly suitable for use with rubbers.

[0071] The weight proportion of component (B) in the pore-forming material is not particularly limited, but is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, and even more preferably 80 to 100% by weight. When the weight proportion is 50% by weight or more, pores tend to be introduced more efficiently. It is preferable that the pore-forming material contains component (B) as the main component.

[0072] The pore-forming material may contain other pore-forming components other than component (B) that have a pore-forming function. The other pore-forming components are not particularly limited, but examples thereof include hollow particles having a resin outer shell; glass balloons; graphite; resin powders such as polyethylene terephthalate (PET) and polymethyl methacrylate (PMMA); chemical foaming agents; and thermally expandable microspheres.

[0073] The molding composition of the present invention may contain components other than the above-mentioned component (A) and component (B), the above-mentioned curing agent, the above-mentioned vulcanization / crosslinking agent, the above-mentioned vulcanization accelerator, and the above-mentioned vulcanization acceleration aid (hereinafter, these may be simply referred to as other components). Examples of other components include conventionally known reinforcing agents, fillers, softeners, processing aids, antioxidants, ultraviolet absorbers, lubricants, pigments, colorants, dispersants, and flame retardants.

[0074] The reinforcing agent is not particularly limited, but examples thereof include carbon black such as SRF, GPF, FEF, HAF, ISAF, SAF, FT, and MT; these carbon blacks that have been surface-treated with a silane coupling agent or the like; finely powdered silicic acid; silica; and inorganic fibers such as glass fiber and carbon fiber, and one or more of these may be used in combination. The filler is not particularly limited, and examples thereof include inorganic fillers such as calcium carbonate, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, talc, clay, glass beads, and glass balloons; and organic fillers such as high styrene resin, coumarone-indene resin, phenolic resin, lignin, modified melamine resin, and petroleum resin, and one or more of these may be used in combination.

[0075] The softener is not particularly limited, and examples thereof include petroleum-based softeners such as process oil, lubricating oil, paraffin, liquid paraffin, petroleum asphalt, and vaseline; coal tar-based softeners such as coal tar and coal tar pitch; fatty oil-based softeners such as castor oil, linseed oil, rapeseed oil, and palm oil; tall oil; sap; waxes such as beeswax, carnauba wax, and lanolin; and fatty acids such as ricinoleic acid, palmitic acid, barium stearate, calcium stearate, and zinc laurate. and fatty acid salts; synthetic polymeric substances such as petroleum resin, atactic polypropylene, and coumarone-indene resin; ester-based plasticizers such as dioctyl phthalate, dioctyl adipate, and dioctyl sebacate; carbonate ester-based plasticizers such as diisododecyl carbonate; microcrystalline wax; sub(factice); liquid polybutadiene; modified liquid polybutadiene; liquid thiokol; hydrocarbon-based synthetic lubricating oils, and the like, may be used alone or in combination of two or more. Examples of lubricants include hydrocarbon-based lubricants such as liquid paraffin; fatty acid-based lubricants such as stearic acid; fatty acid amide-based lubricants such as stearic acid amide; ester-based lubricants such as butyl stearate; alcohol-based lubricants such as stearyl alcohol; and metal soaps, and one or more of these may be used in combination.

[0076] [Molding composition] As described above, the molding composition of the present invention contains the above-mentioned components (A) and (B), and can produce a molded article having internal voids and suppressing a decrease in breaking strength. In the molding composition of the present invention, the content of component (B) is not particularly limited, but is preferably 0.01 to 15 parts by weight, more preferably 0.1 to 10 parts by weight, even more preferably 0.1 to 8 parts by weight, and particularly preferably 0.3 to 5 parts by weight, relative to 100 parts by weight of component (A). When the content is 0.01 part by weight or more, sufficient pores tend to be introduced into the molded article. When the content is 15 parts by weight or less, a decrease in the breaking strength of the molded article tends to be suppressed.

[0077] When component (A) contains a thermosetting resin, the amount of curing agent contained in the molding composition is not particularly limited, but is preferably 0.1 to 100 parts by weight, more preferably 1 to 60 parts by weight, per 100 parts by weight of the thermosetting resin. When the content is within the above range, the curing rate of component (A) and the melting rate of component (B) become close, and uniform pores tend to be introduced into the obtained molded article.

[0078] When component (A) contains rubber, the amount of vulcanizing / crosslinking agent contained in the molding composition is not particularly limited, but is preferably 0.1 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, per 100 parts by weight of rubber. When the content is within the above range, the vulcanization rate and the melting rate become close to each other, and uniform pores tend to be introduced into the obtained molded article. When component (A) contains rubber, the amount of vulcanization accelerator contained in the molding composition is not particularly limited, but is preferably 0.01 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, per 100 parts by weight of rubber. When the content is within the above range, the vulcanization rate and the melting rate become close to each other, and uniform pores tend to be introduced into the obtained molded article. When component (A) contains rubber, the amount of vulcanization accelerator in the molding composition is not particularly limited, but is preferably 0.01 to 20 parts by weight, more preferably 0.1 to 10 parts by weight, per 100 parts by weight of rubber. When the content is within this range, the vulcanization rate and the melting rate become close to each other, and uniform pores tend to be introduced into the obtained molded article.

[0079] The molding composition of the present invention can be produced, for example, by a conventionally known method in which component (A), component (B), a curing agent, a vulcanization / crosslinking agent, a vulcanization accelerator, a vulcanization acceleration aid, and other components are mixed and stirred until homogeneous. When producing the molding composition of the present invention, devices such as a Super Mixer (manufactured by Kawata Corporation) and a High Speed ​​Mixer (manufactured by Earth Technica Corporation), a New Gram Machine (manufactured by Seishin Enterprise Co., Ltd.), an SV Mixer (manufactured by Kobelco Eco-Solutions Co., Ltd.), rolls such as open rolls, a Banbury mixer, a kneader, a pressure kneader, and internal mixers (internal mixers) such as an Intermix may be used.

[0080] When producing the molding composition of the present invention, the above-mentioned pore-forming material may be used. When the above-mentioned pore-forming material is used, it is recommended to adjust the amount of the pore-forming material so that the content of component (B) falls within the above-mentioned range.

[0081] (Molding masterbatch) When producing the molding composition of the present invention, a molding masterbatch containing the above component (B) and the following component (C) may be used. Ingredient (C): Base ingredient By using a molding masterbatch (hereinafter sometimes simply referred to as a masterbatch), component (B) can be uniformly dispersed in component (A).

[0082] The component (C) contained in the masterbatch is a component that forms the masterbatch. Examples of the component (C) include liquid organic compounds, resins, rubbers, etc., and one or more of these may be used in combination.

[0083] The liquid organic compound is not particularly limited, but examples thereof include petroleum-based liquids such as process oil, paraffin oil, liquid paraffin oil, petroleum asphalt, and Vaseline; coal tar-based liquids such as coal tar and coal tar pitch; fatty oil-based liquids such as castor oil, linseed oil, rapeseed oil, and coconut oil; fatty acids such as ricinoleic acid, palmitic acid, and oleic acid; ester-based liquids such as dioctyl phthalate, dioctyl adipate, and dioctyl sebacate; carbonate ester-based liquids such as diisododecyl carbonate; liquid polybutadiene; modified liquid polybutadiene; liquid thiokol; hydrocarbon-based synthetic lubricating oils; nonionic surfactants; alkylene glycols; polyalkylene glycols; and silicone oils, and these may be used alone or in combination. When the masterbatch contains an organic liquid compound as component (C), the masterbatch may be in the form of a wet powder in which component (B) is wetted with the organic liquid compound.

[0084] Examples of the resin include thermosetting resin and thermoplastic resin. The thermosetting resin is not particularly limited, but examples thereof include epoxy resin, phenol resin, unsaturated polyester resin, polyurethane, etc., and one or more of these may be used in combination. The thermoplastic resin is not particularly limited, but examples thereof include elastomer resins; olefin-based resins such as ethylene-vinyl acetate copolymer (EVA), ethylene-methyl (meth)acrylate copolymer, ethylene-α-olefin copolymer, polyethylene, modified polyethylene, polypropylene, modified polypropylene, and modified polyolefin; polyethylene-based resins; polypropylene-based resins; polystyrene-based resins; polyvinyl chloride-based resins; polyester-based resins; polyamide-based resins; polycarbonate-based resins; polyvinyl chloride-based resins; acrylic resins; acrylonitrile-butadiene-styrene resins; and vinyl acetate-based resins, and one or more of these may be used in combination.

[0085] The melting point of the resin is preferably lower than that of component (B). If the melting point of the resin is higher than that of component (B), the shape of component (B) may not be maintained during the production of the masterbatch. The melting point of the resin is not particularly limited as long as it is lower than the melting point of component (B), but is preferably 50 to 130°C, more preferably 60 to 120°C, even more preferably 65 to 120°C, and particularly preferably 70 to 110°C. If the melting point is 50°C or higher, fusion of molding masterbatches tends to be suppressed. If the melting point is 130°C or lower, the dispersibility of component (B) tends to be improved when producing a molded product.

[0086] The rubber is not particularly limited, and examples thereof include diene rubbers such as natural rubber, isoprene rubber, butadiene rubber, styrene-butadiene rubber, chloroprene rubber, acrylonitrile-butadiene rubber, ethylene-α-olefin copolymer rubber, ethylene-α-olefin-non-conjugated diene copolymer rubber, halogenated ethylene-α-olefin-non-conjugated diene copolymer rubber, sulfonated ethylene-α-olefin-non-conjugated diene copolymer rubber, maleated ethylene-α-olefin-non-conjugated diene copolymer rubber, butyl rubber, and isobutylene-isoprene rubber; and non-diene rubbers such as hydrogenated nitrile rubber, urethane rubber, silicone rubber, chlorosulfonated polyethylene, chlorinated polyethylene, acrylic rubber, epichlorohydrin rubber, fluororubber, polysulfide rubber, and propylene oxide rubber, and the like. These may be used alone or in combination of two or more. Component (C) is not particularly limited, but is preferably at least one selected from petroleum-based liquids, olefin-based resins, and diene-based rubbers. The masterbatch may use the above component (A) as component (C).

[0087] In addition to component (B) and component (C), the masterbatch may contain the reinforcing agent, the filler, the processing aid, the antioxidant, the ultraviolet absorber, the pigment, the colorant, the flame retardant, a pore-forming material other than component (B), and the like.

[0088] The amount of component (B) contained in the masterbatch is not particularly limited, but is preferably more than 15 parts by weight and not more than 350 parts by weight, more preferably 20 to 300 parts by weight, even more preferably 30 to 200 parts by weight, and particularly preferably 50 to 150 parts by weight, per 100 parts by weight of component (C). If the content is more than 15 parts by weight, a molded product with reduced decrease in breaking strength tends to be obtained. If the content is 350 parts by weight or less, component (B) tends to be dispersed uniformly.

[0089] Examples of methods for producing the masterbatch include a conventionally known method in which component (B), component (C), and other components other than component (B) and component (C) are mixed and stirred until homogeneous. When producing the masterbatch, devices such as a Super Mixer (manufactured by Kawata Corporation) and a High Speed ​​Mixer (manufactured by Earth Technica Corporation), a New Gram Machine (manufactured by Seishin Enterprise Co., Ltd.), an SV Mixer (manufactured by Kobelco Eco-Solutions Co., Ltd.), rolls such as open rolls, a Banbury mixer, a kneader, a pressure kneader, and internal mixers (internal mixers) such as Intermix may be used.

[0090] When producing the masterbatch, component (B) will melt if the temperature is not lower than the melting point of component (B). In general, to prevent component (B) from melting, the masterbatch is produced at a temperature that is preferably at least 10°C lower, more preferably at least 15°C lower than the melting point of component (B). When the above masterbatch is used in producing the molding composition of the present invention, the amount of the masterbatch blended may be adjusted so that the content of component (B) falls within the above range.

[0091] When producing the molding composition of the present invention, component (B) will melt if the temperature is not lower than the melting point of component (B). In general, to prevent component (B) from melting, the molding composition is produced at a temperature that is preferably at least 10°C lower, more preferably at least 15°C lower than the melting point of component (B).

[0092] [Molded body] The molded article of the present invention is obtained by molding the above molding composition, and curing the above molding composition by heating. The molded article of the present invention has pores inside.

[0093] The circularity of the pores inside the molded body is not particularly limited, but is preferably 0.70 to 1.0, more preferably 0.80 to 1.0, and even more preferably 0.85 to 0.95. When the circularity is 0.70 or more, the decrease in the breaking strength of the obtained molded body tends to be suppressed. The circularity of the pores inside the molded body is measured by the method described in the examples.

[0094] Examples of methods for producing the molded article of the present invention include molding methods such as extrusion molding, calendar roll molding, press molding, injection molding, transfer molding, and mold molding, and press molding, injection molding, extrusion molding, and mold molding are particularly preferred. By these molding methods, the molding composition is molded into the intended shape and can be cured simultaneously with molding or by introducing the molded product into a heater bath.

[0095] The curing method may involve, for example, heating a molding composition containing a curing agent and a vulcanizing / crosslinking agent. The heating temperature is not particularly limited, but is preferably higher than the melting point of component (B), preferably 20°C to 150°C higher, and more preferably 50°C to 100°C higher than the melting point of component (B). The heating time is not particularly limited, but is preferably 10 to 180 minutes, more preferably 20 to 120 minutes. A heating time of 10 minutes or more tends to result in a molded product having sufficient pores and being sufficiently cured. A heating time of 180 minutes or less tends to prevent a decrease in the breaking strength of the obtained molded product.

[0096] The molded article of the present invention has independent pores uniformly formed inside, and has excellent impact resistance, heat insulation properties, rigidity, etc., and can be suitably used in a variety of fields, such as automobile and various vehicle parts such as hoses and weather strips; electric wires, electric wire joints, sealing materials, gaskets, etc.; civil engineering and construction parts such as construction gaskets, construction water stop sheets, and civil engineering water stop sheets; office automation equipment rolls such as charging rolls, transfer rolls, developing rolls, and paper feed rolls; industrial rolls such as steelmaking rolls, papermaking rolls, printing wire rolls, and industrial rolls; and general industrial parts. [Example]

[0097] The present invention will be described in detail with reference to the following Production Examples, Examples, and Comparative Examples, but the present invention is not limited thereto. In the following, unless otherwise specified, "%" means "% by weight" and "parts" means "parts by weight." In the following examples and comparative examples, physical properties were measured in the following manner.

[0098] [Measurement of average particle size (D50) of component (B)] The measurement device used was a laser diffraction scattering particle size distribution analyzer (MT3000II) manufactured by Microtrack Bell Co., Ltd., and the D50 value obtained by volume-based measurement was used as the average particle size.

[0099] [Measurement of true specific gravity of component (B)] Measurements were performed using the immersion method (Archimedes method) using isopropyl alcohol in an atmosphere with an ambient temperature of 25°C and a relative humidity of 50%. Specifically, a 100 mL volumetric flask was emptied and dried, and the weight of the volumetric flask (WB1) was measured. The weighed volumetric flask was then filled with isopropyl alcohol exactly up to the meniscus, and the weight of the volumetric flask filled with 100 mL of isopropyl alcohol (WB2) was measured. The 100 mL volumetric flask was also emptied and dried, and the weight of the volumetric flask (WS1) was measured. Approximately 50 mL of component (B) was then filled into the weighed volumetric flask, and the weight of the volumetric flask filled with component (B) (WS2) was measured. The volumetric flask filled with component (B) was then filled with isopropyl alcohol exactly up to the meniscus, taking care not to introduce air bubbles, and the weight (WS3) was measured. The obtained WB1, WB2, WS1, WS2, and WS3 were then introduced into the following formula to calculate the true specific gravity (d) of component (B). d={(WS2-WS1)×(WB2-WB1) / 100} / {(WB2-WB1)-(WS3-WS2)}

[0100] [Measurement of circularity of component (B)] After fixing the component (B) to double-sided tape, it was sputtered with platinum and photographed using a scanning electron microscope (Keyence Corporation, VE-8800) at an acceleration voltage of 20 kV and a magnification of 30x to obtain an electron micrograph. The area (a) (projected area) and perimeter (b) of 100 components (B) randomly selected from the electron micrograph were measured using image analysis particle size distribution measurement software Mac-View (Mountec Co., Ltd.), and the circularity of each component (B) was calculated using the following formula. The average value of the circularities of the 100 components (B) obtained was taken as the circularity of the component (B). Circularity = 4πa / b 2

[0101] [Measurement of melting point, fusion enthalpy (ΔHm), and crystallization enthalpy (ΔHc) of component (B)] Measurement was performed according to the method described in JIS K7122:2012 "Method for measuring heat of transition of plastics." However, the sampling method and temperature conditions were as follows. A differential scanning calorimeter (DSC4000, manufactured by Perkin Elmer) was used. Approximately 10 mg of component (B) was filled into the bottom of the measurement vessel so that no gaps were present. The sample was held at 30°C for 10 minutes under a nitrogen flow rate of 20 mL / min, and then heated from 30°C to 250°C at a heating rate of 10°C / min. A DSC curve was obtained. The temperature at which the endothermic peak in the obtained DSC curve reached its maximum was taken as the melting point, and the melting enthalpy (ΔHm) was calculated from the area of ​​the endothermic peak. Furthermore, the crystallization enthalpy (ΔHc) was calculated from the area of ​​the peak obtained by holding the sample at 250°C for 10 minutes after the heating and then cooling it to 30°C at a cooling rate of 10°C / min. When multiple peaks were present, the melting enthalpy (ΔHm) and crystallization enthalpy (ΔHc) were calculated by summing the areas of all peaks.

[0102] [Measurement of circularity and diameter of pores inside a molded body] The molded body was cut, and the resulting cross section was sputtered with platinum. Then, an electron microscope photograph was taken using a scanning electron microscope (Keyence Corporation, VE-8800) at an acceleration voltage of 20 kV and a magnification of 30x to obtain an electron micrograph. The diameter of 100 randomly selected pores from the electron microscope photograph was measured using image analysis particle size distribution measurement software Mac-View (Mountec Co., Ltd.), and the average value was used as the pore diameter inside the molded body. The projected area (c) (projected area) and perimeter (d) of each pore were measured, and the circularity of each pore was calculated using the following formula. The average circularity of the 100 pores obtained was used as the circularity of the pores inside the molded body. Circularity = 4πc / d 2

[0103] [Evaluation of tensile breaking strength of molded body] JIS No. 3 dumbbell-shaped test pieces were cut out from the obtained molded body in accordance with JIS K6251:2017. The tensile strength at break of the No. 3 dumbbell pieces was measured at 500 mm / min and an ambient temperature of 25°C, and an index was calculated with Comparative Example 1 as 100. A larger index of tensile strength at break indicates a higher strength of the molded body.

[0104] [Evaluation of Compression Set of Molded Product] The compression set of the obtained molded article was measured under conditions of 70°C, 22 hours, and 25% compression according to a method in accordance with JIS K6262, and an index was calculated with Comparative Example 1 set to 100. A larger compression set index indicates higher dimensional stability of the molded article.

[0105] [Production of component (B) (particles)] <Production Example 1> 300 parts by weight of ion-exchanged water, 100 parts by weight of polybutylene succinate adipate (PBSA), 0.5 parts by weight of sorbitan monolaurate, and 20 parts by weight of polyvinyl alcohol were mixed and placed in a 1 L pressure-resistant container, which was then sealed. The internal temperature of the container was raised to 140°C, the initial pressure was set to 0.2 MPa, and the mixture was stirred at 300 rpm for 5 hours. The mixture was then cooled to 50°C to obtain an aqueous dispersion of particles. The obtained aqueous dispersion was filtered, dried, and subsequently classified to obtain Particles 1. The weight percentage of the thermoplastic resin in the particles was 99.7%, the weight percentage of surfactant was 0.2%, and the weight percentage of polyvinyl alcohol was 0.1%. The obtained particles had an average particle size of 15.8 μm, a true specific gravity of 1.24, a circularity of 0.86, a melting point (measured by DSC) of 86°C, a melting enthalpy ΔHm of 68 J / g, a crystallization enthalpy ΔHc of 54 J / g, and a ΔHm / ΔHc of 1.26.

[0106] <Production Example 2> In Production Example 2, particles 2 were obtained in the same manner as in Production Example 1, except that the production conditions in Production Example 1 were changed as shown in Table 1, and after filtration, the particles were redispersed in a large amount of hot water at 90°C and subjected to another filtration step. The results are shown in Table 1.

[0107] <Production Examples 3 to 8 and Production Comparative Examples 1 and 2> In Production Examples 3 to 8 and Production Comparative Examples 1 and 2, particles 3 to 10 were obtained in the same manner as in Production Example 1, except that the production conditions in Production Example 1 were changed as shown in Table 1. The results are shown in Table 1.

[0108] [Table 1]

[0109] [Preparation of Masterbatch (MB1)] 50 parts of ethylene-methyl methacrylate copolymer (melting point 80°C, melt flow rate 7 g / 10 min, methyl methacrylate content 25%), 10 parts of process oil (Idemitsu Kosan Co., Ltd., DAIANA PROCESS OIL PW-90), and 5 parts of stearic acid as a lubricant were kneaded in a Banbury mixer, and when the temperature reached approximately 100°C, 50 parts of particles 2 obtained in Production Example 2 were added, and the mixture was kneaded for an additional 30 seconds to obtain a kneaded product. The obtained kneaded product was extruded and simultaneously pelletized to obtain a masterbatch (MB1).

[0110] [Preparation of Masterbatch (MB2)] 50 parts of EPDM (Mooney viscosity [ML1+4 (100°C)] 8, ethylene content 54%, diene component: ENB, diene content 7.6%, propylene content 38.4%), 50 parts of process oil (Idemitsu Kosan Co., Ltd., DAIANA PROCESS OIL PW-90), and 5 parts of stearic acid as a lubricant were kneaded in a pressure kneader until the material temperature reached 80°C, and then 100 parts of particles 2 obtained in Production Example 2 were added and kneaded at 80°C for 3 minutes to obtain a kneaded product. The obtained kneaded product was mixed in a roller mill at a roll temperature of 60°C, a roll speed of 20 rpm, and a roll distance of 1 cm for 3 minutes to obtain a 1 cm thick sheet-like masterbatch (MB2).

[0111] [Preparation of Component (A) (Unvulcanized Rubber)] 60 parts of natural rubber, 40 parts of butadiene rubber, 20 parts of carbon black, 20 parts of process oil, 3 parts of stearic acid, 3 parts of zinc oxide, 2 parts of sulfur, 1 part of vulcanization accelerator, and 2 parts of antioxidant were kneaded in a 15 L Banbury mixer to prepare unvulcanized rubber. Details of the raw materials used in preparing the unvulcanized rubber are shown below. Natural rubber: RSS#3 Butadiene rubber: Ube Industries, Ltd., BR150B Carbon black: Diablack SA, manufactured by Mitsubishi Chemical Corporation Process oil: Idemitsu Kosan Co., Ltd., DAIANA PROCESS OIL NS-28 Stearic acid: Tokyo Chemical Industry Co., Ltd. Zinc oxide: manufactured by Tokyo Chemical Industry Co., Ltd. Sulfur: Tsurumi Chemical Industry Co., Ltd. Vulcanization accelerator: Noccela CZ, manufactured by Ouchi Shinko Chemical Industry Co., Ltd. Anti-aging agent: Nocrac 6C, manufactured by Ouchi Shinko Chemical Industry Co., Ltd.

[0112] Example 1 3 parts of the particles 1 obtained in Production Example 1 and 97 parts of unvulcanized rubber were kneaded using an open roll at 60°C for 5 minutes to obtain a molding composition. The obtained molding composition was press-vulcanized at 170°C for 20 minutes to obtain a molded article. The obtained molded article was evaluated. The results are shown in Table 2.

[0113] <Examples 2 to 10 and Comparative Examples 1 to 3> In Examples 2 to 10 and Comparative Examples 1 to 3, molding compositions and molded articles were obtained and evaluated in the same manner as in Example 1, except that the conditions in Example 1 were changed as shown in Tables 2 and 3. The results are shown in Tables 2 and 3.

[0114] Example 11 6 parts of the MB1 obtained above and 94 parts of unvulcanized rubber were kneaded using an open roll at 60°C for 5 minutes to obtain a molding composition. The obtained molding composition was press-vulcanized at 170°C for 20 minutes to obtain a molded article. The obtained molded article was evaluated. The results are shown in Table 3.

[0115] Example 12 Eight parts of the MB2 obtained above and 92 parts of unvulcanized rubber were kneaded using an open roll at 60°C for 5 minutes to obtain a molding composition. The obtained molding composition was press-vulcanized at 170°C for 20 minutes to obtain a molded article. The obtained molded article was evaluated. The results are shown in Table 3.

[0116] [Table 2]

[0117] [Table 3]

[0118] As can be seen from Tables 2 and 3, Examples 1 to 12 confirm that the effects of the present application can be achieved when the molding composition contains component (A) (a thermosetting matrix component) and component (B) (particles containing a thermoplastic resin, which have a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.0). On the other hand, in Comparative Examples 1 to 3, it was confirmed that the effects of the present invention could not be obtained when the molding composition did not contain component (B).

Claims

1. A molding composition comprising the following component (A) and the following component (B): Component (A): Thermosetting matrix component Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.

0.

2. 2. The molding composition according to claim 1, wherein the true specific gravity of said component (B) is 0.65 to 1.

4.

3. 3. The molding composition according to claim 1, wherein the circularity of component (B) is 0.70 to 1.

0.

4. The molding composition according to claim 1 or 2, wherein the thermoplastic resin comprises at least one selected from an olefin-based resin and a polyester-based resin.

5. 3. The molding composition according to claim 1, wherein the component (A) is at least one selected from the group consisting of a thermosetting resin and a rubber.

6. 3. The molding composition according to claim 1, wherein the content of said component (B) is 0.01 to 15 parts by weight per 100 parts by weight of component (A).

7. A molded article obtained by molding the molding composition according to claim 1 or 2.

8. A pore-forming material comprising the following component (B): Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.

0.

9. A molding masterbatch comprising the following component (B) and the following component (C): Component (B): Particles containing a thermoplastic resin, having a melting point measured by a differential scanning calorimeter (DSC) of 70 to 150°C, a melting enthalpy (ΔHm) measured by a differential scanning calorimeter (DSC) of 50 to 200 J / g, and a ratio (ΔHm / ΔHc) of the melting enthalpy (ΔHm) to the crystallization enthalpy (ΔHc) measured by a differential scanning calorimeter (DSC) of 0.3 to 2.

0. Component (C): Base component

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