JP5205811B2 - Thermosetting resin composition, cured product - Google Patents

Description

  The present invention relates to a thermosetting resin composition and a cured product obtained by curing it.

  Conventionally, as a method for enhancing the toughness of an epoxy resin, a method of adding a modifier such as a rubber component or a thermoplastic resin to the epoxy resin composition is known. As a method of adding a rubber component, a method of adding a reactive liquid rubber (such as CTBN) or a nitrile rubber (for example, see Patent Document 1) is known. However, since the reactive liquid rubber undergoes a process of once dissolving in the epoxy resin and then phase-separating at the time of curing, the morphology of the cured product changes depending on the type of epoxy resin to be blended and the curing conditions. In addition to the fact that the modification effect cannot be obtained or there is a problem in the reproducibility of the quality, the rubber component partially dissolves and remains in the cured epoxy resin phase. (Hereinafter, also referred to as Tg) has been lowered, resulting in a problem that the quality of the epoxy resin product is lowered. Furthermore, if the epoxy resin product itself is large and the curing temperature for producing the product varies depending on the part, the quality may vary depending on the part.

  As a method for solving the problem of morphological change and its control due to the addition of the rubber component, a composition in which rubber-like particles are dispersed in the epoxy resin is obtained by polymerizing monomers such as acrylate esters in the epoxy resin. The obtaining method is known (for example, refer to Patent Document 2). However, even in the above method, it is unavoidable that a part of the rubber component is dissolved in the cured epoxy resin phase, and the glass transition temperature may be lowered, so that the quality is not sufficient.

  On the other hand, as a method for adding a thermoplastic resin, it is well known that a thermoplastic resin having a high glass transition temperature (so-called super engineering plastic or the like) is used. In this method, it is possible to impart a certain degree of toughness while maintaining the glass transition temperature and heat resistance of the cured product, but generally, since a large amount of addition is required, the viscosity of the system increases and there is a problem in handling properties. In addition, there are problems that complicated processes such as dissolution are required and morphological control is required.

In addition, the epoxy resin composition containing rubber-like polymer particles insoluble in the epoxy resin prevents the heat resistance (glass transition temperature) from decreasing because the rubber component does not dissolve in the cured epoxy resin phase. Can do. The rubber-like polymer particles in this case are not polymerized in the epoxy resin, but are prepolymerized and mixed with the epoxy resin. As such rubber-like polymer particles, a so-called core-shell polymer is representative (see, for example, Patent Document 3 or Patent Document 4). Further, these core-shell polymers are commercially available as primary particle aggregates (aggregates), for example, in the form of powders of several tens to several hundreds of microns. The mixed core-shell polymer is easy if it is not pulverized or mixed thoroughly with a kneader such as a heated stirrer, a high-speed shear stirrer, a hot roll, an intermixer, a kneader, or a triple roll at a temperature of 50 to 200 ° C. There is a problem of sedimentation or separation by floating. Even after careful mixing and kneading over several hours, the mixed core-shell polymer is agglomerated without being dispersed with primary particles, and depending on the type of epoxy resin, the mixed core-shell polymer is easy to separate, etc. This problem is unsatisfactory because of this problem and the need to add a dispersion stabilizer. Furthermore, since the size of the core-shell polymer actually dispersed in the epoxy resin is not the primary particles, there is a problem that it is difficult to optimize the design of the core-shell polymer particles. Under these circumstances, commercially available powdery core-shell polymers do not have sufficient performance as epoxy resin reinforcing agents.
Japanese Patent Publication No.62-34251 JP 59-138254 A U.S. Pat. No. 3,322,852 US Pat. No. 3,496,250

  The object of the present invention is to overcome the various problems associated with the epoxy resin reinforcement of the prior art as described above, and to provide a cured product having a high toughness with excellent elastic modulus without impairing heat resistance and the like. The object is to provide a resin composition and a cured product obtained by curing the resin composition.

  That is, the present invention comprises (1) an epoxy resin (A), a core-shell polymer (B) having a carboxyl group present in a shell part through a side chain having 3 or more atoms extending from the polymer main chain, a curing agent, and The present invention relates to a thermosetting resin composition comprising a curing catalyst (C).

  Moreover, this invention relates to the thermosetting resin composition as described in said (1) characterized by (2) The theoretical glass transition temperature of the shell part (B) of the said core-shell polymer is 20 degrees C or less.

  In the present invention, (3) the core portion of the core-shell polymer (B) is a half ester of a dicarboxylic acid having 2 or more carbon atoms, and a compound having a (meth) acryloyloxyalkylene group in the ester portion is polymerized. The thermosetting resin composition as described in (1) or (2) above, comprising the polymer obtained.

  In the present invention, (4) the core part of the core-shell polymer (B) is selected from a diene rubber polymer, an acrylic rubber polymer, a silicon rubber polymer, and an olefin rubber polymer. It is at least 1 type, It is related with the thermosetting resin composition as described in any one of said (1)-(3) characterized by the glass transition temperature of a core part being 0 degrees C or less.

  The present invention also relates to (5) the thermosetting resin composition according to any one of (1) to (4), wherein the core-shell polymer (B) is crosslinked fine particles.

  Moreover, this invention is (6) The thermosetting resin composition as described in any one of said (1)-(5) characterized by the particle diameter of the said core-shell polymer (B) being 30-500 nm. Related to things.

  The present invention also includes (7) a curing accelerator, an inorganic filler, an organic or polymer filler, a flame retardant, an antistatic agent, a conductivity imparting agent, a lubricant, a slidability imparting agent, a surfactant, and a colorant. The thermosetting resin composition according to any one of (1) to (6), wherein the thermosetting resin composition includes one or more additives selected from the group consisting of:

  Moreover, this invention relates to the core-shell polymer as described in any one of said (1)-(7) characterized by mixing with (8) epoxy resin.

  Moreover, this invention relates to the hardened | cured material obtained by thermosetting the thermosetting resin composition as described in any one of (9) said (1)-(7).

  The present invention also relates to the cured product according to (9), wherein (10) the core-shell polymer (B) is dispersed in an epoxy resin phase with a particle size of 30 to 500 nm even after curing. .

  According to the present invention, it is possible to provide a thermosetting resin composition that gives a cured product having excellent elasticity and high toughness without impairing heat resistance and the like, and a cured product obtained by curing it. .

  The thermosetting resin composition of the present invention comprises an epoxy resin (A), a core-shell polymer (B) having a carboxyl group existing in a shell part through a side chain having 3 or more atoms extending from the polymer main chain, and a cured And / or a curing catalyst (C).

  The epoxy resin (A) used in the present invention is not particularly limited as long as it is an epoxy resin used for an interlayer insulating film or a planarizing film of a multilayer circuit board, a protective film or an electric insulating film of an electronic component, for example, Bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, bisphenol S type epoxy resin, brominated bisphenol A type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy Resin, fluorene type epoxy resin, spiro ring type epoxy resin, bisphenolalkane type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin, brominated cresol novolac type epoxy resin, trishydroxy Tan type epoxy resin, tetraphenylol ethane type epoxy resin, alicyclic epoxy resin, alcohol type epoxy resin, butyl glycidyl ether, phenyl glycidyl ether, cresyl glycidyl ether, nonyl glycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl Ether, polypropylene glycol diglycidyl ether, glycerin polyglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, hexahydrophthalic acid diglycidyl ether, fatty acid-modified epoxy resin Toluidine type epoxy resin, aniline type epoxy resin, aminophenol type epoxy resin, , 3-bis (N, N-diglycidylaminomethyl) cyclohexane, hindered-in type epoxy resin, triglycidyl isocyanurate, tetraglycidyl diaminodiphenylmethane, diphenyl ether type epoxy resin, dicyclopentadiene type epoxy resin, dimer acid diglycidyl ester, hexa Examples include hydrophthalic acid diglycidyl ester, dimer acid diglycidyl ether, silicone-modified epoxy resin, silicon-containing epoxy resin, urethane-modified epoxy resin, NBR-modified epoxy resin, CTBN-modified epoxy resin, and epoxidized polybutadiene. Among these, a phenol novolac type epoxy resin is preferable. These epoxy resins may be used alone or in combination of two or more.

  The core-shell polymer (B) that can be used in the present invention includes a core part (B-1) and a shell part (B-2) that forms an outer layer of the core part. The core part (B-1) is preferably made of a polymer mainly composed of an elastomer or rubber-like polymer, and the shell part (B-2) is made of a polymer component graft-polymerized to the core part (B-1). Is preferred.

  The polymer constituting the core part (B-1) is not particularly limited as long as it does not inhibit grafting with the shell part (B-2). For example, butadiene rubber, styrene-butadiene rubber, acrylonitrile-butadiene rubber, etc. Diene rubber polymers: butyl acrylate rubber, butadiene-butyl acrylate rubber, 2-ethylhexyl acrylate-butyl acrylate rubber, 2-ethylhexyl methacrylate-butyl acrylate rubber, stearyl acrylate-butyl acrylate rubber, dimethylsiloxane-acrylic acid Acrylic rubber polymers such as butyl rubber and silicon / butyl acrylate composite rubber; Olefin rubber polymers such as ethylene-propylene rubber and ethylene-propylene-diene rubber; Silicon rubber polymers such as polydimethylsiloxane These may be used alone or in combination of two or more. Among these, styrene-butadiene rubber, acrylonitrile-butadiene rubber, 2-ethylhexyl acrylate-butyl acrylate rubber, and the like are used.

The core part (B-1) preferably has a glass transition temperature of 0 ° C. or lower,
More preferably, it is −10 ° C. or lower. When the glass transition temperature of the said core part (B-1) exceeds 0 degreeC, it exists in the tendency for the thermal expansion coefficient of the thermosetting resin composition obtained to become small easily. The glass transition temperature of the core part (B-1) can be measured by a differential scanning calorimetry (DSC method).
The shell portion of the core-shell polymer has a carboxyl group present via a side chain having 3 or more atoms extending from the polymer main chain. When the number of atoms in the side chain is less than 3, the life after mixing with the epoxy resin is short, and if it is cured after being allowed to stand to some extent, aggregates tend to increase, resulting in problems such as deterioration in appearance and performance.

It is. The number of atoms in the side chain is preferably 3-18, more preferably 6-12. The polymer constituting the shell part (B-2) is graft-polymerized to the polymer constituting the core part (B-1), and is substantially bonded to the polymer constituting the core part (B-1). Preferably, those having swelling property, compatibility or affinity for the organic solvent and epoxy resin (A) described later are preferable. The theoretical glass transition temperature of the shell part (B-2) is preferably 20 ° C. or lower, more preferably 10 ° C. or lower, and particularly preferably 0 ° C. or lower. When the theoretical glass transition temperature of the shell part (B-2) exceeds 20 ° C., the thermal expansion coefficient of the resulting thermosetting resin composition tends not to decrease. The theoretical glass transition temperature of the shell part (B-2) can be calculated from the following equation. 1 / Tg = W ₁ / T ₁ + W ₂ / T ₂ +... W _n / T _{n
W 1, W} 2 ··· _{W n} in the formula is the weight percent of each monomer (= (amount / total weight of the monomers in each _{monomer) × 100), T 1,} T 2 ··· T n is It is the glass transition temperature (absolute temperature) of the homopolymer of each monomer.

  The polymer constituting the shell part (B-2) is a polymer obtained by polymerizing a compound having a (meth) acryloyloxyalkylene group in the ester part, which is a half ester of a dicarboxylic acid having 2 or more carbon atoms. preferable. Examples of the compound having a carbon number of 2 or more dicarboxylic acid and having a (meth) acryloyloxyalkylene group in the ester moiety include, for example, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl. Examples include phthalic acid, 2- (meth) acryloyloxyethyl maleic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, and these may be used alone or in admixture of two or more. Among these, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl phthalic acid, and the like are used.

  The above compound can be obtained by dehydrating a dicarboxylic anhydride such as succinic anhydride, phthalic anhydride, maleic anhydride, hexahydrophthalic anhydride and the like with 2-hydroxyethyl (meth) acrylate. The core-shell polymer using a polymer obtained by polymerizing a dicarboxylic acid half ester having a (meth) acryloyloxyalkylene group in the ester portion as the shell portion and having a carbon number of 1 or less has a short life after mixing with the epoxy resin, to some extent When it is allowed to cure after being allowed to stand, there is a tendency that aggregates increase and problems such as appearance and performance deterioration occur.

In addition, a compound having a (meth) acryloyloxyalkylene group in the ester portion, which is a half ester of a dicarboxylic acid having 2 or more carbon atoms, from the viewpoint that both good graft polymerizability and affinity for an epoxy resin can be achieved. You may copolymerize the monomer copolymerizable with. Examples of such copolymerizable monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, and i- (meth) acrylate. Butyl, t-butyl (meth) acrylate, pentyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, (meth) acrylic acid (Meth) acrylic such as dodecyl, octadecyl (meth) acrylate, butoxyethyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, naphthyl (meth) acrylate, glycidyl (meth) acrylate Acid esters: α-methylstyrene, α-ethylstyrene, α-fluorostyrene, α-chlorostyrene, α-butyl Aromatic vinyl compounds such as lomostyrene, fluorostyrene, chlorostyrene, bromostyrene, methylstyrene, methoxystyrene; (meth) acrylamides such as (meth) acrylamide, N-dimethyl (meth) acrylamide, N-diethyl (meth) acrylamide ; Unsaturation of (meth) acrylic acid metal salts such as calcium (meth) acrylate, barium (meth) acrylate, lead (meth) acrylate, tin (meth) acrylate acrylate, zinc (meth) acrylate Fatty acids; vinyl cyanide compounds such as (meth) acrylonitrile, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, trimethylcyclohexyl (meth) acrylate, norbornyl (meth) acrylate, (Meta Norbornyl methyl acrylate, cyanonorbornyl (meth) acrylate, isobornyl (meth) acrylate, bornyl (meth) acrylate, menthyl (meth) acrylate, fentil (meth) acrylate, (meth) acrylic acid Adamantyl, dimethyladamantyl (meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] dec-8-yl (meth) acrylate, tricyclo [5.2.1.0 ^2, (meth) acrylate ⁶ ] Deca-4-methyl, (meth) acrylic acid ester having an alicyclic hydrocarbon group such as cyclodecyl (meth) acrylate; N-methylmaleimide, N-ethylmaleimide, N-propylmaleimide, Ni- Propyl maleimide, N-butyl maleimide, Ni-butyl maleimide, Nt-butyl maleimide, N-lauryl male N-cyclohexylmaleimide, N-benzylmaleimide, N-phenylmaleimide, N- (2-chlorophenyl) maleimide, N- (4-chlorophenyl) maleimide, N- (4-bromophenyl) phenylmaleimide, N- (2 -Methylphenyl) maleimide, N- (2-ethylphenylmaleimide), N- (2-methoxyphenyl) maleimide, N- (2,4,6-trimethylphenyl) maleimide, N- (4-benzylphenyl) maleimide, N N-substituted maleimides such as-(2,4,6-tribromophenyl) maleimide; Moreover, you may use these by 1 type (s) or 2 or more types. Among these, n-butyl acrylate, 2-ethylhexyl acrylate, and the like are used.

  In the present invention, the core-shell polymer (B) is preferably crosslinked fine particles. A compound having a (meth) acryloyloxyalkylene group in the ester part, which is a half ester of the dicarboxylic acid having 2 or more carbon atoms forming the shell part (B-2) in order to make the core-shell polymer (B) into a crosslinked particle. Is preferably copolymerized with a monomer having two or more (meth) acryloyl groups or vinyl groups in the molecule. Examples of the monomer having two or more (meth) acryloyl groups or vinyl groups in the molecule include ethylene glycol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4- Butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol di (meth) ) Acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, (meth) acryl modified Monomers having two or more (meth) acryloyl groups in the molecule such as dimethyl siloxane; Monomers having two or more vinyl groups in the molecule such as divinylbenzene; Bisphenol A diglycidyl ether (meth) Acrylic acid adduct, bisphenol A polyoxyethylene-added diglycidyl ether (meth) acrylic acid adduct, bisphenol A polyoxypropylene-added diglycidyl ether (meth) acrylic acid adduct, trimethylolpropane (meth) acrylic acid benzoate And a monomer having two or more (meth) acryloyl groups in the molecule having a benzene ring in the side chain. Among these, a monomer having two or more (meth) acryloyl groups in a molecule having a benzene ring in the side chain increases compatibility or affinity for the organic solvent and the epoxy resin (A). be able to. These monomers can be used alone or in combination of two or more. Among these monomers, among them, 1,6-hexanediol diacrylate, diethylene glycol diacrylate, and the like are used.

  The amount of the monomer having two or more (meth) acryloyl groups or vinyl groups in the molecule is 1 part by weight or more with respect to 100 parts by weight of the monomer constituting the shell part (B-2). It is preferably 2 parts by weight or more. When the amount of the monomer having two or more (meth) acryloyl groups or vinyl groups in the molecule is less than 1 part by weight, crosslinking tends to be insufficient.

  The weight ratio of the core part (B-1) / shell part (B-2) in the core-shell polymer (B) used in the present invention is preferably in the range of 30/70 to 90/10, 40/60 to More preferably, it is in the range of 80/20. When the weight ratio of the core part (B-1) / shell part (B-2) exceeds 30/70 (the ratio of the core part (B-1) is less than 30), it is based on the epoxy resin (A). There is a tendency for the effect of improving toughness to decrease. When the weight ratio of the core part (B-1) / shell part (B-2) exceeds 90/10 (the ratio of the shell part (B-2) is less than 10), it tends to aggregate during handling. There is a possibility that the expected physical properties may not be obtained.

  When the core-shell polymer (B) is a crosslinked particle, the particle diameter is preferably 30 to 500 nm, more preferably 40 to 200 nm, and particularly preferably 45 to 150 nm. When the particle size is less than 30 nm, it is difficult to obtain a core having a particle size smaller than 30 nm, which is not preferable from the viewpoint of mass productivity. When the particle size exceeds 500 nm, the resulting thermosetting resin composition is obtained. The glass transition temperature of the glass tends to decrease. The particle diameter of the crosslinked particles can be measured using an ultrafine particle size distribution meter (MICROTRAC UPA150 manufactured by Lees & Northrup). The method for controlling the particle size of the crosslinked particles is not particularly limited. For example, when the core-shell polymer (B) is synthesized by emulsion polymerization, the particle size is controlled by controlling the number of micelles during emulsion polymerization according to the amount of emulsifier used. Can be controlled.

  In this invention, it is preferable that the compounding quantity of a core shell polymer (B) is 1-100 weight part with respect to 100 weight part of said epoxy resins (A), and it is more preferable that it is 5-100 weight part. By setting the blending amount of the core-shell polymer (B) in the range of 1 to 100 parts by weight, the toughness of the resulting cured product is improved, and cracks are less likely to occur in the cured part during long-term use. The compatibility between the core-shell polymer (B) and other components is improved, and the heat resistance of the obtained cured product is easily improved.

  There are no particular limitations on the method for producing such a core-shell polymer (B), and well-known methods such as emulsion polymerization, suspension polymerization, and microsuspension polymerization can be used. Among these, a production method by an emulsion polymerization method is preferable.

The method for producing the core-shell polymer (B) by the emulsion polymerization method is, for example, firstly polymerizing the polymer (b-1) to be the core part (B-1), and using this polymer (b-1) as a seed particle for a predetermined amount. Is added to another polymerization vessel, and then the method of polymerizing the monomer that gives the polymer (b-2) to be the shell part (B-2), or the polymer (b-1) is polymerized, and the same polymerization vessel And a method of polymerizing a monomer that gives the polymer (b-2). As a method of charging the monomer mixture that gives the polymer (b-2), a method in which the monomer mixture is charged all at once and polymerized, and after the polymerization of a part of the monomer mixture, the rest is continuously or intermittently performed. For example, a method in which the monomer mixture is continuously added from the beginning to the end of the polymerization, or a method in which these charging methods are combined. The polymerization temperature is usually 50 to 90 ° C. at the core portion and 30 to 90 ° C. at the shell portion.
In producing the core-shell polymer (B) by emulsion polymerization, monomers are emulsified in water using a surfactant, and a radical polymerization initiator such as a peroxide catalyst or a redox catalyst is used as a polymerization initiator. Furthermore, if necessary, a polymer emulsion can be synthesized by adding a molecular weight regulator such as a mercaptan-based compound or a halogenated hydrocarbon to perform polymerization. The core-shell polymer (B) can be isolated by polymer precipitation from this polymer emulsion and drying.

  The surfactant used in the production of the core-shell polymer (B) by emulsion polymerization is not particularly limited. For example, an anionic surfactant such as alkylbenzene sulfonate; alkyl naphthalene sulfonate, alkyl trimethyl ammonium salt, dialkyl Cationic surfactants such as dimethylammonium salts; nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acid esters, fatty acid monoglycerides, and amphoteric interfaces Activators; as well as reactive emulsifiers can be used. These surfactants can be used alone or in combination of two or more. The amount of the surfactant used in the production method of the present invention is preferably 0.01 to 25% by weight based on 100% by weight of the total amount of monomers used. When the amount of the surfactant used is less than 0.01% by weight, aggregates tend to be generated during the polymerization reaction. When the amount of the surfactant used exceeds 25% by weight, it becomes difficult to agglomerate the polymer fine particles, and the remaining surfactant tends to affect as an impurity.

  Examples of the method for precipitating the polymer from the polymer emulsion include a method of adding a polyvalent metal salt such as calcium chloride, magnesium sulfate and aluminum sulfate, a coagulant such as sodium chloride and sulfuric acid; alcohols such as methanol and ethanol; acetone , A method of adding an organic solvent such as methyl ethyl ketone; a method of using a nonionic surfactant, performing emulsion polymerization at a temperature below the cloud point of the nonionic surfactant, and then heating to the cloud point or higher; A method in which after emulsion polymerization is performed using a surfactant, a non-ionic surfactant having a lower cloud point than that of the nonionic surfactant, an electrolyte alcohol, a fatty acid and the like are added and heated; anionic and / or cationic After emulsion polymerization using a surfactant and a nonionic surfactant, the nonionic And a method of than the active agent is added a nonionic surfactant or an electrolyte of a low cloud point heating can be mentioned.

  The polymer coagulum precipitated from the polymer emulsion can be washed with water, washed with methanol, etc. as necessary. Subsequently, the core-shell polymer (B) is isolated by subjecting the polymer coagulum to a dehydration treatment using a centrifugal dehydrator or the like, and optionally a drying treatment. Here, the water content of the core-shell polymer (B) after the dehydration (drying) treatment is preferably less than 5% by weight, and more preferably less than 1% by weight. The core-shell polymer (B) having a moisture content of less than 1% by weight can be suitably used for applications such as adhesives.

  In the present invention, as a method of mixing the core-shell polymer (B) with the epoxy resin (A), for example, a method of mixing a polymer emulsion obtained by emulsion polymerization with the epoxy resin (A), a core-shell isolated from the polymer emulsion Examples thereof include a method in which the polymer (B) is dispersed in advance in a desired organic solvent and then mixed with the epoxy resin (A).

  The organic solvent used for dispersing the core-shell polymer (B) is not particularly limited. For example, ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate; propylene glycol monomethyl ether, propylene Propylene glycol monoalkyl ethers such as glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether; propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether ;Propylene glycol Propylene glycol monoalkyl ether acetates such as nomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate; cellosolves such as ethyl cellosolve and butyl cellosolve; carbitols such as butyl carbitol Lactic acid esters such as methyl lactate, ethyl lactate, n-propyl lactate, isopropyl lactate; ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, propionic acid Aliphatic carboxylic acid esters such as isopropyl, n-butyl propionate, isobutyl propionate; methyl 3-methoxypropionate, 3-methoxy Other esters such as ethyl lopionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate; aromatic hydrocarbons such as toluene, xylene; 2-heptanone, 3-heptanone And ketones such as 4-heptanone and cyclohexanone; amides such as N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide and N-methylpyrrolidone; and lactones such as γ-butyrolacun. . These organic solvents can be used individually by 1 type or in mixture of 2 or more types. Among these organic solvents, an organic solvent close to the solubility parameter of the polymer (b-2) constituting the shell part (B-2) is preferable, and a London dispersion force term generally used in the calculation method of Hansen and Hoy, The sum of the squares of the differences between the dipole force term and the hydrogen bond force term is preferably 16 or less.

  As a method for dispersing the organic solvent in the core-shell polymer (B), the core-shell polymer (B) is introduced into the organic solvent, and a “core mixer” (manufactured by Special Machine Industries Co., Ltd.) is used. B) Crushing is performed until the particle size becomes 0.5 mm or less, and then using “ultrasonic homogenizer” (manufactured by Emerson Japan Ltd.), “nanomizer” (manufactured by Yoshida Kikai Kogyo Co., Ltd.), etc. It is preferable to carry out dispersion up to.

  The curing agent and the curing catalyst (C) used in the present invention are not particularly limited. For example, aliphatic or aromatic amines, polyamide resins, carboxylic acids, acid anhydrides, phenol resins, polysulfide resins, Examples thereof include polyvinylphenols, dicyandiamide, dibasic acid dihydrazide, imidazoles, organic boron, organic phosphine, guanidine, and salts thereof. These can be used individually by 1 type or in combination of 2 or more types. For the purpose of accelerating the curing reaction, a curing accelerator can be used in combination with the curing catalyst. Here, the “curing agent” is one that forms a crosslinked structure by itself, and the “curing catalyst” is one that does not form a crosslinked structure by itself, but promotes a crosslinking reaction, and “curing accelerator” Is to increase the catalytic action of the curing catalyst.

  The blending amount of the (C) curing agent and / or curing catalyst is preferably 0.1 to 20 parts by weight, and 0.5 to 10 parts by weight with respect to 100 parts by weight of the epoxy resin (A). It is more preferable.

  The thermosetting resin composition of the present invention includes, as necessary, an organic solvent, an adhesion assistant, a leveling agent, an inorganic filler, an organic or polymer filler, a conductivity imparting agent, a lubricant, a slidability imparting agent, Contains colorants, polymer additives, reactive diluents, wettability improvers, surfactants, plasticizers, antioxidants, antistatic agents, antifungal agents, humidity control agents, flame retardants and other additives These additives can be used in amounts that do not impair the effects of the present invention.

  Moreover, the thermosetting resin composition of the present invention can contain a resin other than the epoxy resin (A) (hereinafter also referred to as “other resin”) within a range not impairing the effects of the present invention. Other resins include, for example, resins having phenolic hydroxyl groups, polyimides, acrylic polymers, polystyrene resins, polyolefin elastomers, styrene butadiene elastomers, silicone elastomers, tolylene diisocyanate and other diisocyanate compounds and blocked products thereof, and high density polyethylene. , Medium density polyethylene, polypropylene, polycarbonate, polyarylate, polyamide, polyamideimide, polysulfone, polyethersulfone, polyetherketone, polyphenylene sulfide, (modified) polycarbodiimide, polyetherimide, polyesterimide, modified polyphenylene oxide, phenolic hydroxyl group And thermoplastic or thermosetting resins such as resins having oxetane groups and resins having oxetane groups. Can.

  The thermosetting resin composition according to the present invention can provide a cured product having high toughness with excellent elastic modulus without deteriorating heat resistance and the like, with each component exhibiting good compatibility. In the cured product of the present invention, the core-shell polymer (B) is dispersed in the epoxy resin phase with a particle size of 30 to 500 nm, and can be confirmed by, for example, a transmission electron microscope image (TEM image) shown in FIG. .

  Accordingly, the thermosetting resin composition of the present invention is particularly useful for interlayer insulating films or planarizing films for multilayer circuit boards, protective films or electric insulating films for various electric devices and electronic components, and adhesives for various electronic materials. It can be used very suitably for condenser films and the like. Also, it can be suitably used as a semiconductor sealing material, an underfill material, a liquid crystal sealing material, or the like. Moreover, a copper-clad laminate is prepared by impregnating a glass cloth or the like with the liquid thermosetting resin composition and then drying the prepreg, or impregnating the glass cloth or the like with the solvent-free thermosetting resin composition. It can also be used as a laminated material. Furthermore, the thermosetting resin composition of the present invention can also be used as a thermosetting molding material in the form of powder, pellets, and the like.

  The thermosetting resin composition according to the present invention is applied to a suitable support that has been surface-treated in advance to form a thermosetting thin film, and the thin film is transferred to a substrate together with the support using a laminator and then cured. Thus, a substrate having a cured product layer and a support layer can be obtained.

  Moreover, when the film which carried out the surface mold release process is used as a support body, a thermosetting resin layer can be formed by peeling only a support body after transfer to a base material.

The obtained thermosetting film can be used as a low-stress adhesive film for electrical equipment and electronic parts.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but these do not limit the scope of the present invention.

Example 1
(1) Manufacture of polymer emulsion 1360 g of pure water in a 4 L glass container, 328 g of Emulgen 109P (nonionic surfactant, trade name manufactured by Kao Corporation) previously diluted in a 30% aqueous solution as a surfactant, and 98 g of net 800 g of Nipol 1562 (acrylonitrile-butadiene rubber, product name of Nippon Zeon Co., Ltd., glass transition temperature—20 ° C.), 800 g, was stirred and mixed, and nitrogen substitution was performed. Thereafter, a mixture of 280 g of butyl acrylate, 15 g of 1,6-hexanediol diacrylate, 31 g of 2-acryloyloxyethyl phthalic acid and 4 g of cumene hydroperoxide as a polymerization initiator was added, and impregnation was performed for 1 hour while stirring. After the impregnation, the temperature was raised at 40 ° C. After heating, 0.15 parts by weight of potassium persulfate dissolved in 2 parts by weight of pure water was added, and the temperature was raised to 60 ° C. After the temperature rise, 6 g of sodium pyrophosphate and 0.008 g of iron (II) sulfate dissolved in 50 g of pure water were added and stirring was continued for 6 hours to obtain a polymer emulsion in which core-shell polymer particles were dispersed. The reaction rate at this time was 95%. The weight ratio of the core part / shell part of the obtained core-shell polymer (I) was 50/50. Moreover, the glass transition temperature (theoretical glass transition temperature) of the shell part was −51 ° C.

  The average particle size of the polymer particles in the obtained polymer emulsion was measured in the state of the emulsion subjected to the following treatment using an ultrafine particle size distribution meter (MICROTRAC UPA150 manufactured by Lees & Northrup).

  The obtained polymer emulsion was diluted 100 times with pure water and irradiated with ultrasonic waves for 3 minutes using an ultrasonic cleaner (LEO Ultrasonic LEO-80: frequency 46 Hz, output 80 W). The particles were dispersed. The emulsion in which the polymer particles were dispersed was placed in the particle size distribution meter, and the particle size was measured. The measurement time was 3 minutes.

Measurement conditions Light source: Diode laser (780 nm, 3 mW)
Measurement range: Full range (0.0032 to 6.5406 μm)
Particle properties: Transparent, spherical particles Dispersion medium: Water Analysis of the obtained measurement data by the attached program (MICROTRAC Data Handling System SD-UPA150-100 manufactured by Mountec) revealed that 50% average particle diameter of polymer particles Was 70 nm.

(2) Preparation and evaluation of resin composition for glass woven fabric impregnation and measurement substrate Novolak phenol type epoxy resin N-770 (trade name, manufactured by Dainippon Ink & Chemicals, Inc.) 30 g, novolac phenol resin HP-850 (trade name, Hitachi Chemical Co., Ltd.) 16 g, Dicyandiamide (trade name, Nippon Carbide Co., Ltd.) 0.04 g, core shell polymer (I) 2.5 g synthesized above, curing accelerator 2PZ-CNS-PW (trade name, Shikoku) 0.1 g of Kasei Kogyo Co., Ltd. and 80 g of methyl ethyl ketone (reagent) were mixed to prepare a resin composition.

The resin composition obtained as described above is impregnated into a 0.2 mm-thick glass woven fabric (weighing 210 g / m ² ), heated at 160 ° C. for 3 minutes, and semi-cured (B stage state) prepreg (resin-containing 55% by weight). A semi-cured resin is collected from the prepreg to form a powder, and a Teflon (registered trademark) sheet is cured as a spacer and a release sheet at 175 ° C. for 90 minutes under 2.5 MPa pressing conditions, and a 0.2 mm thick resin plate And a measurement substrate was obtained.

The obtained measurement substrate was measured for elastic modulus, coefficient of thermal expansion, and glass transition temperature. The results are shown in Table 1.
The elastic modulus was measured at 50 ° C. using a dynamic viscoelastic spectrometer DVE-V4 manufactured by Rheology under the conditions of a distance between chucks of 20 mm, a frequency of 10 Hz, and a heating rate of 3 ° C./min. The coefficient of thermal expansion was measured from a value of 40 ° C. to 120 ° C. using SSC / 5200 manufactured by Seiko Instruments, with a temperature rising rate of 2 ° C./min and a measurement mode as a tensile mode. The glass transition temperature was measured under the same conditions as the elastic modulus.

Example 2
A polymer emulsion was produced in the same manner as in Example 1 (1) except that 31 g of 2-acryloyloxyethyl phthalic acid was changed to 31 g of 2-acryloyloxyethyl succinic acid in the production of the polymer emulsion (reaction rate 95%). . The weight ratio of the core part / shell part of the obtained core-shell polymer (II) was 50/50, and the particle diameter of the core-shell polymer (II) was 74 nm. Moreover, the glass transition temperature (theoretical glass transition temperature) of the shell part was −50 ° C.

Next, a resin composition and a measurement substrate were prepared in the same manner as in Example 1 (2) except that the core-shell polymer (II) was used instead of the core-shell polymer (I), and the elastic modulus, thermal expansion coefficient, glass The transition temperature was measured. The results are shown in Table 1.
Example 3
A polymer emulsion was produced in the same manner as in Example 1 (1) except that the amount of 2-acryloyloxyethylphthalic acid used in the production of the polymer emulsion was changed to 62 g (reaction rate 97%). The weight ratio of the core part / shell part of the obtained core-shell polymer (III) was 50/50, and the particle diameter of the core-shell polymer (III) was 115 nm. Moreover, the glass transition temperature (theoretical glass transition temperature) of the shell part was −50 ° C.

Next, a resin composition and a measurement substrate were prepared in the same manner as in Example 1 (2) except that the core-shell polymer (III) was used instead of the core-shell polymer (I), and the elastic modulus, thermal expansion coefficient, glass The transition temperature was measured. The results are shown in Table 1.
Comparative Example 1
Example except that in place of the core-shell polymer (I), Paraloid EXL2655 (trade name, manufactured by Rohm and Haas Co., Ltd., average particle size 0.2 μm) having an acrylic glass body and a carboxylic acid functional group is used instead of the core-shell polymer (I) A resin composition and a measurement substrate were prepared in the same manner as in 1 (2), and the elastic modulus, thermal expansion coefficient, and glass transition temperature were measured. The results are shown in Table 1.
Comparative Example 2
The same as Example 1 (2) except that in place of the core-shell polymer (I), non-core-shell XER-91 (trade name, manufactured by JSR Corporation, average particle diameter: 70 nm), which is a carboxylic acid-modified NBR particle, is used. To prepare a resin composition and a measurement substrate, and the elastic modulus, thermal expansion coefficient, and glass transition temperature were measured. The results are shown in Table 1.
Comparative Example 3
Resin composition and measurement were carried out in the same manner as in Example 1 (2) except that CTBN (Ube Industries, Ltd., carboxyl group-terminated liquid rubber), which is a liquid rubber, was used instead of the core-shell polymer (I). A substrate was prepared, and the elastic modulus, thermal expansion coefficient, and glass transition temperature were measured. The results are shown in Table 1.
Comparative Example 4
A resin composition and a measurement substrate were prepared in the same manner as in Example 1 (2) except that the core-shell polymer (I) was not used, and the elastic modulus, thermal expansion coefficient, and glass transition temperature were measured. The results are shown in Table 1.

  Examples 1 to 3 were able to improve the glass transition temperature while reducing the elastic modulus and the thermal expansion coefficient as compared with Comparative Example 4 in which the core-shell polymer (I) was not used. On the other hand, Comparative Examples 1 to 3 can reduce the elastic modulus and the coefficient of thermal expansion, but the glass transition temperature is lowered.

It is a transmission electron microscope image (TEM image) of the hardened | cured material of this invention.

Claims (8)

An epoxy resin (A), a core-shell polymer (B) having a carboxyl group existing through a side chain having 3 or more atoms extending from the polymer main chain in the shell, and a curing agent and / or a curing catalyst (C). A thermosetting resin composition in which the theoretical glass transition temperature of the shell portion of the core-shell polymer (B) is 20 ° C. or lower . The shell part of the core-shell polymer (B) is a polymer obtained by polymerizing a compound having a (meth) acryloyloxyalkylene group in the ester part, which is a half ester of a dicarboxylic acid having 2 or more carbon atoms. The thermosetting resin composition according to claim 1 . The core part of the core-shell polymer (B) is at least one selected from a diene rubber polymer, an acrylic rubber polymer, a silicon rubber polymer, and an olefin rubber polymer, and the glass of the core part the thermosetting resin composition according to claim 1 or 2, characterized in that transition temperature of 0 ℃ or less. The core-shell polymer (B) is a thermosetting resin composition according to any one of claims 1 to 3, wherein the cross-linked microparticle. The thermosetting resin composition according to any one of claims 1 to 4 , wherein the core-shell polymer (B) has a particle size of 30 to 500 nm. One or more additives selected from curing accelerators, inorganic fillers, organic or polymer fillers, flame retardants, antistatic agents, conductivity imparting agents, lubricants, slidability imparting agents, surfactants, and colorants the characterized in that it contains a thermosetting resin composition according to any one of claims 1-5. Hardened | cured material obtained by thermosetting the thermosetting resin composition as described in any one of Claims 1-6 . The cured product according to claim 7 , wherein the core-shell polymer (B) is dispersed in the epoxy resin phase with a particle size of 30 to 500 nm even after curing.