KR20100030567A - Phenolic hardener and epoxy resin composition using the phenolic hardener - Google Patents

Abstract

PURPOSE: An epoxy resin composition is provided to ensure fluidity at a low temperature compared with a conventional epoxy resin composition, to enable the hardening at a low temperature, and to ensure good applicability and filling ability. CONSTITUTION: A phenolic hardener used as a hardener for an epoxy resin comprises (a) a vinylphenol unit represented by chemical formula 1 and (b) a vinylether unit represented by chemical formula 2, as a copolymer with two or more phenolic hydroxyl groups within one molecule. In chemical formula 1, R1 is hydrogen atom or C1-4 alkyl group, and n is 1 or 2.

Description

Phenolic hardener and epoxy resin composition using this phenolic hardener {PHENOLIC HARDENER AND EPOXY RESIN COMPOSITION USING THE PHENOLIC HARDENER}

The present invention relates to a phenolic curing agent, and more particularly, to a novel phenolic curing agent used as a curing agent for epoxy resins and an epoxy resin composition using the same. The epoxy resin composition obtained can be used for various uses, such as a resin composition for electronic materials and a coating agent.

Although the epoxy resin composition uses various hardening | curing agents at the time of hardening, it is known that the performance of hardened | cured material differs largely according to the kind of hardening | curing agent, The hardening | curing agent is distinguished and used according to the use of the said epoxy resin composition. In particular, phenolic curing agents have excellent balance of physical properties such as adhesion, water resistance and electrical performance, and are widely used as curing agents for epoxy resins in the electric and electronic fields.

Among the said phenolic hardening | curing agents, especially polyvinyl phenol is known that it is excellent in an electrical resistance characteristic, and various uses are examined as a resin composition for electronic materials (for example, patent document 1, 2 etc.). However, circuits mounted on precision devices such as electronic devices and communication devices have recently increased in speed and density, and higher performance is required for epoxy resin compositions containing polyvinylphenol as a curing agent.

For example, since the warpage of a semiconductor package or a semiconductor element is caused by the difference in thermal expansion coefficient of each constituent member, it is desired to lower the curing temperature. However, since polyvinylphenol has a high glass transition temperature, a certain high temperature is required in order to reach a viscosity sufficiently following the surface to be deposited in the molten state until curing, and insufficient curing at low temperatures. The curing temperature could not be lowered.

Moreover, in order to absorb and relieve the stress which arises by the difference of a thermal expansion coefficient, it is desired to set it as a low elastic modulus, maintaining the hardness and heat resistance of hardened | cured material, but in the epoxy resin composition which uses a polyvinyl phenol as a hardening | curing agent, Three-dimensional crosslinking increased the elastic modulus of the cured product and was unable to absorb distortion (that is, deformation) based on the difference in thermal expansion coefficient of each component.

On the other hand, in order to improve the fluidity at low temperatures and lower the curing temperature, it is necessary to add a thermoplastic component having a low glass transition temperature to the epoxy resin composition or to add a low molecular weight component to improve the fluidity. Moreover, the method of adding a rubber component to an epoxy resin composition is known as a method of absorbing distortion based on the difference of the thermal expansion coefficient of each structural member, and improving a thermal stress relaxation characteristic. However, when a thermoplastic component or a rubber component having a low glass transition temperature is added to the epoxy resin composition, the fluidity and thermal stress relaxation characteristics can be improved, but the heat resistance may decrease or the coefficient of linear expansion may increase, and it may be compatible with other components. There is a problem that the properties are lowered, not uniformly mixed, causing phase separation.

On the other hand, Patent Document 3 has a vinylphenol unit and a repeating unit derived from a monomer giving a polymer having a glass transition temperature such as (meth) acrylic acid ester, 1,3-butadiene or isoprene at 0 ° C or less. It is shown that the thermosetting resin composition which mix | blended the copolymer gives the hardened | cured material excellent in insulation characteristic, heat resistance, and also thermal shock. However, the polymer containing a (meth) acrylate unit has a problem that the effect of improving thermal stress relaxation is not great and, on the contrary, the water resistance and the electrical properties are deteriorated, and further, repeating units such as 1,3-butadiene are included. Although the copolymer which is said to improve thermal stress relaxation property, there existed a problem that compatibility and substrate adhesiveness worsen.

Moreover, in the case of the liquid epoxy resin composition used for the sealing material for semiconductor packages, in order to prevent a crack, curvature, and peeling, by mix | blending a large amount of inorganic filler, the linear expansion rate of hardened | cured epoxy resin is made small, and a cure shrinkage rate is made small. Is done. In addition, in the case of a conductive adhesive, a die-bonding paste, and an anisotropic conductive paste, in order to provide electroconductivity, it is necessary to mix | blend a conductive filler with epoxy resin in large quantities. Thus, in order to mix | blend an inorganic filler and a conductive filler with an epoxy resin composition in large quantities, it is necessary to use the low viscosity resin binder. However, since polyvinylphenol is generally provided as a solid, when used in a liquid or paste state, there is a problem that the viscosity becomes high and the applicability and filling due to inflow are poor.

As a method of decreasing the viscosity of an epoxy resin composition, the method of melt | dissolving in a solvent and adjusting the viscosity of an epoxy resin composition is known, for example. However, when a large amount of solvent is used, in applications such as conductive pastes, voids are generated in the cured product as traces of the removal of the solvent during curing heating, which leads to a decrease in adhesive strength, thermal conductivity, and conductivity, thereby increasing reliability. It is not desirable from the point of view. Moreover, there also exists a problem that a working environment deteriorates by evaporation of a solvent. Moreover, although the method of using a reactive diluent as a solvent is also known (for example, patent document 4), since the reactive diluent produces volume shrinkage at the time of hardening, too much use is unpreferable.

[Patent Document 1] Japanese Unexamined Patent Publication No. 10-008006

[Patent Document 2] Japanese Unexamined Patent Publication No. 2002-335079

[Patent Document 3] Japanese Unexamined Patent Publication No. 2001-247656

[Patent Document 4] Japanese Unexamined Patent Publication No. 2003-26766.

Therefore, the subject of this invention is fluidity at low temperature compared with the conventional epoxy resin composition containing polyvinylphenol, hardening at low temperature is possible, and thermal stress is not impaired without impairing the heat resistance of the hardened | cured material obtained. It is providing the novel epoxy resin composition which can improve a relaxation characteristic. Moreover, it is providing the low viscosity epoxy resin composition which has favorable applicability | paintability and filling property in a solventless or less solvent amount.

MEANS TO SOLVE THE PROBLEM In order to solve this problem, the present inventors earnestly examined and found that the said subject can be solved by using the copolymer of specific vinylphenol and vinyl ether as a phenolic hardening | curing agent, and completed this invention.

That is, the present invention is a phenolic curing agent used as a curing agent of the epoxy resin, and includes a vinylphenol unit (a) represented by the following formula (1) and a vinyl ether unit (b) represented by the following formula (2) Is a copolymer having two or more phenolic hydroxyl groups in one molecule:

(Wherein R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms and n represents 1 or 2)

[In formula, R <_2> is a C1-C6 linear or branched alkyl group, a C1-C6 linear or branched fluoroalkyl group, a C2-C6 alkoxyalkyl group, a C5-C10 cycloalkyl group, or less. An aryl group or an arylalkyl group represented by the formula (3):

(Wherein m is 0, 1, 2 or 3, X is an unsubstituted phenyl group, or one or more linear or branched alkyl groups having 1 to 4 carbon atoms, a linear or branched fluoroalkyl group having 1 to 4 carbon atoms) , An alkoxy group having 1 to 4 carbon atoms or a phenyl group substituted with a halogen atom).

Moreover, this invention is an epoxy resin composition containing the said phenolic hardening | curing agent and an epoxy resin.

By incorporating the phenolic curing agent of the present invention into an epoxy resin, it has fluidity even at a low temperature compared to a conventional epoxy resin composition containing polyvinylphenol, enables curing at low temperatures, and also impairs the heat resistance of the cured product. The epoxy resin composition which can provide the hardened | cured material excellent in stress relaxation property can be obtained. Therefore, this epoxy resin composition becomes a low-viscosity epoxy resin composition which has a good coating property and a filling property in a solventless or less solvent amount.

Therefore, the epoxy resin composition which mix | blended the phenolic hardening | curing agent of this invention can be used suitably as a resin composition for electronic materials, for example. Specifically, the resin composition for prepreg for a printed circuit board, the resin composition for copper clad laminated boards for a printed circuit board, the coating agent for interlayer insulation materials of a build-up printed circuit board, and a semiconductor Resin composition for interlayer insulation film, resin composition for sealant of electronic component, resin composition for sealant of semiconductor chip, resin cured for underfill, resist ink, conductive paste, resin composition for molded parts for electronic component storage and anisotropic conductive film It can use for various uses, such as a composition.

Moreover, the epoxy resin composition of this invention is excellent in hardness and adhesiveness, and can be used also for various uses, such as a coating composition and an adhesive agent.

The phenolic curing agent of the present invention comprises a vinylphenol unit (a) represented by the formula (1) and a vinyl ether unit (b) represented by the formula (2), wherein the air having two or more phenolic hydroxyl groups in one molecule It is coalescing.

In the general formula (1), examples of the alkyl group having 1 to 4 carbon atoms represented by R ₁ include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, isobutyl group and the like. Can be.

In addition, in the definition of R _{2 in} the formula (2), examples of the linear or branched alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group , Isobutyl group, n-amyl group, isoamyl group and the like. Moreover, as a C1-C6 linear or branched fluoroalkyl group, the fluoroalkyl group in which all or some hydrogen of the C1-C6 linear or branched alkyl group was substituted by fluorine is mentioned as an example. , Trifluoromethyl group, pentafluoroethyl group, 2,2,2-trifluoroethyl group and the like.

Moreover, as a C2-C6 alkoxyalkyl group, a methoxymethyl group, an ethoxymethyl group, 2-methoxyethyl group, 2-ethoxyethyl group, 2-tetrahydropyranyl group, 2-tetrahydrofuranyl group, etc. are mentioned, Examples of the cycloalkyl group having 5 to 10 carbon atoms include cyclopentyl group, cyclohexyl group, cycloheptyl group, cyclooctyl group, bicyclo [2.2.1] heptyl group, bicyclo [2.2.2] octyl group, and tricyclo [5.2. 1.0 ^2,6 ] decanyl group, adamantyl group, etc. are mentioned.

On the other hand, among the groups represented by the general formula (3), examples of the aryl group include a phenyl group, methylphenyl group, ethylphenyl group, methoxyphenyl group, ethoxyphenyl group, fluorophenyl group, trifluoromethylphenyl group and the like, and benzyl group as the arylalkyl group. And methyl benzyl group, ethyl benzyl group, methoxy benzyl group, ethoxy benzyl group, fluorobenzyl group, trifluoromethylbenzyl group and the like.

Such a copolymer is derived from a vinylphenol-based monomer capable of inducing a vinylphenol unit (a) represented by the formula (1) or a monomer protecting its hydroxyl group, and a vinyl ether unit (b) represented by the formula (2). It is obtained by copolymerizing the vinyl ether monomer which can be obtained.

As a vinylphenol type monomer which can derive a vinylphenol unit (a), For example, p-hydroxy styrene, m-hydroxy styrene, o-hydroxy styrene, p-isopropenyl phenol, m -Isopropenylphenol, o-isopropenylphenol, etc. are mentioned. Among these, p-hydroxy styrene, m-hydroxy styrene, p-isopropenyl phenol, and m-isopropenyl phenol can be used preferably.

Moreover, as a monomer which protected these hydroxyl groups, p-methoxy styrene, m-methoxy styrene, p-ethoxy styrene, m-ethoxy styrene, p-propoxy styrene, m, for example -Propoxy styrene, p-isopropoxy styrene, m-isopropoxy styrene, pn-butoxy cystyrene, mn-butoxy styrene, p-isobutoxy styrene, m-isobutoxy styrene Alkoxy styrenes such as ene, p-tert-butoxy styrene and m-tert-butoxy styrene;

p-methoxymethoxystyrene, m-methoxymethoxystyrene, p- (1-ethoxyethoxy) styrene, m- (1-ethoxyethoxy) styrene, p- (2-tetra Alkoxyalkyloxystyrenes such as hydropyranyl) oxystyrene and m- (2-tetrahydropyranyl) oxystyrene;

alkanoyloxystyrenes such as p-acetoxy styrene, m-acetoxy styrene, p-tert-butylcarbonyloxystyrene, and m-tert-butylcarbonyloxystyrene;

alkoxycarbonyloxystyrenes such as p-methoxycarbonyloxystyrene, m-methoxycarbonyloxystyrene, p-tert-butoxycarbonyloxystyrene and m-tert-butoxycarbonyloxystyrene Lens;

alkoxycarbonylalkyloxystyrenes such as p-tert-butoxycarbonylmethyloxystyrene and m-tert-butoxycarbonyloxymethylstyrene;

alkylsilyloxystyrenes such as p-trimethylsilyloxystyrene, m-trimethylsilyloxystyrene, p-tert-butyldimethylsilyloxystyrene and m-tert-butyldimethylsilyloxystyrene Can be mentioned. Among these, p-tert-butoxy styrene, m-tert-butoxy styrene, p-acetoxy styrene, m-acetoxy styrene, etc. can be used preferably.

In addition, as a vinyl ether type monomer which can induce a vinyl ether unit (b), for example, methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl Alkyl vinyl ethers such as ether, sec-butyl vinyl ether, tert-butyl vinyl ether, isobutyl vinyl ether, n-amyl vinyl ether and isoamyl vinyl ether;

Fluoroalkyl vinyl ethers such as trifluoromethyl vinyl ether, pentafluoroethyl vinyl ether, and 2,2,2-trifluoroethyl vinyl ether;

Alkoxyalkyl vinyl ethers such as 2-methoxyethyl vinyl ether, 2-ethoxyethyl vinyl ether, 2-tetrahydropyranylvinyl ether and 2-tetrahydrofuranylvinyl ether;

Cyclopentylvinylether, cyclohexylvinylether, cycloheptylvinylether, cyclooctylvinylether, 2-bicyclo [2.2.1] heptylvinylether, 2-bicyclo [2.2.2] octylvinyl Cycloalkyl vinyl ethers such as 8-tricyclo [5.2.1.0 ^2,6 ] decanylvinylether, 1-adamantylvinylether and 2-adamantylvinylether;

Aryl vinyl ethers such as phenyl vinyl ether, 4-methylphenyl vinyl ether, 4-trifluoromethylphenyl vinyl ether, and 4-fluorophenyl vinyl ether;

Aryl alkyl vinyl ethers, such as benzyl vinyl ether and 4-fluoro benzyl vinyl ether, etc. are mentioned. Among these, in particular, methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, sec-butyl vinyl ether, tert-butyl vinyl ether, isobutyl vinyl Lower alkyl vinyl ethers such as ether, n-amyl vinyl ether and isoamyl vinyl ether can be preferably used.

These vinylphenol type monomers, the monomer which protected the hydroxyl group, and the vinyl ether type monomer may be used individually by 1 type, respectively, and may be used in combination of 2 or more type.

In the copolymer which comprises the phenolic hardening | curing agent of this invention, in order to express the characteristic of the hardened | cured material obtained effectively, it is preferable that the repeating unit (a) and the repeating unit (b) respectively form a block, and especially vinylphenol It is preferable to form an ABA type triblock in which the unit (a) is an A segment and the vinyl ether unit (b) is a B segment.

Moreover, for the low viscosity, it is preferable that the composition ratio (molar ratio) of the repeating unit (a) and repeating unit (b) contained in a copolymer is 1/99-10/90, and it is 3/97-7/93 More preferably, the viscosity at 50 ° C of the copolymer is more preferably 100000 mPa · s or less.

Although the polymerization method for manufacturing the copolymer of this invention is not specifically limited, For example, radical polymerization, (living) cationic polymerization (living) cationic polymerization, etc. are mentioned, The molecular structure of the copolymer obtained, In consideration of control of the composition ratio and the like, living cationic polymerization is preferable.

For example, ABA type triblock copolymer which has the vinylphenol unit (a) as A segment and the vinyl ether unit (b) as B segment which is the most preferable embodiment of this invention is a bifunctional initiator, It is obtained by living cation polymerization of the vinyl ether monomer in the presence of a Lewis acid and a solvent, followed by addition of a monomer protecting the vinyl phenolic monomer or the hydroxyl group thereof to carry out a living cation polymerization and deprotection treatment if necessary. Can be.

As the difunctional initiator used in the above, those having a structure represented by the following general formula (4) can be used:

(In formula, R <_4> represents a C1-C10 alkylene group and R <_5> represents a hydrogen atom or a C1-C4 alkyl group.).

Specific examples of the alkylene group having 1 to 10 carbon atoms represented by R ₄ in the above formula (4), a methylene group, an ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, heptamethylene group, octamethylene group And nona methylene group, decamethylene group, cyclohexylene group, etc. are mentioned. Moreover, as a specific example of a C1-C4 alkyl group in the definition of R <_5> , a methyl group, an ethyl group, a propyl group, an isopropyl group, n-butyl group, sec-butyl group, tert- butyl group, isobutyl group, etc. are mentioned. Can be mentioned.

As a specific example of the compound represented by the formula (4),

1,1-bis (1-acetoxymethoxy) methane, 1,2-bis (1-acetoxymethoxy) ethane,

1,3-bis (1-acetoxymethoxy) propane, 1,4-bis (1-acetoxymethoxy) ethane,

1,2-bis (1-acetoxymethoxy) butane, 1,5-bis (1-acetoxymethoxy) ethane,

1,2-bis (1-acetoxymethoxy) pentane, 1,6-bis (1-acetoxymethoxy) hexane,

1,7-bis (1-acetoxymethoxy) heptane, 1,8-bis (1-acetoxymethoxy) octane,

1,9-bis (1-acetoxymethoxy) nonane, 1,10-bis (1-acetoxymethoxy) decane,

1,1-bis (1-acetoxyethoxy) methane, 1,2-bis (1-acetoxyethoxy) ethane,

1,3-bis (1-acetoxyethoxy) propane, 1,4-bis (1-acetoxyethoxy) butane,

1,5-bis (1-acetoxyethoxy) pentane, 1,6-bis (1-acetoxyethoxy) hexane,

1,7-bis (1-acetoxyethoxy) heptane, 1,8-bis (1-acetoxyethoxy) octane,

1,9-bis (1-acetoxyethoxy) nonane, 1,10-bis (1-acetoxyethoxy) decane,

1,4-bis (1-acetoxymethoxy) cyclohexane,

1, 4-bis (1-acetoxy ethoxy) cyclohexane, etc. are mentioned. Among them, 1,4-bis (1-acetoxyethoxy) butane, 1,4-bis (1-acetoxyethoxy) cyclohexane and the like can be preferably used. These compounds can be obtained by adding acetic acid to 1,4-butanediol divinyl ether or 1,4-cyclohexanediol divinyl ether.

There is no restriction | limiting in particular in the addition amount of a bifunctional initiator in manufacture of the said ABA type triblock copolymer, It is suitably determined by the molecular weight of the target copolymer.

In addition, as a Lewis acid used in manufacture of an ABA type | mold triblock copolymer, the Lewis acid generally used for the cation polymerization of a vinyl ether type monomer can be used without a restriction | limiting in particular. Specifically, for example, organometallic halides such as Et _1.5 AlCl _1.5 , TiCl ₄ , TiBr ₄ , BCl ₃ , BF ₃ , BF ₃ · OEt ₂ , SnCl ₂ , SnCl ₄ , SbCl ₅ , SbF ₅ , WCl to _{6, TaCl 5, VCl 5,} FeCl 3, ZnBr 2, a metal halide such as AlCl _3, AlBr ₃ may be optionally used.

Although the usage-amount of this Lewis acid is not specifically limited, It can set in consideration of the polymerization characteristic, polymerization concentration, etc. of the vinyl ether monomer used. Usually, it can be used in 0.1-100 mol% with respect to a vinyl ether monomer, Preferably it can be used in the range of 1-50 mol%.

Moreover, as a solvent, Aromatic hydrocarbon solvents, such as benzene, toluene, xylene; Propane, n-butane, isobutane, n-pentane, n-hexane, n-heptane, n-octane, isooctane, decane, hexadecane, isopentane, n-hexa Aliphatic hydrocarbon solvents such as hexane; Halogenated hydrocarbon solvents such as ethylene chloride, methylene chloride and carbon tetrachloride; And ether solvents such as tetrahydrofuran (THF), dioxane, diethyl ether, dibutyl ether, and ethylene glycol diethyl ether. Among these solvents, toluene, methylene chloride and THF are preferably used. These solvents may be used alone or in combination of two or more kinds thereof.

In the polymerization reaction of the ABA type triblock copolymer, a solvent, a vinyl ether monomer, a bifunctional initiator, and a Lewis acid are sequentially added to the reaction vessel, and the segment B including the vinyl ether unit (b) is first Are synthesized. Then, at the end of the conversion of the vinyl ether monomer, a vinyl phenol monomer (or a monomer protected by the hydroxyl group) is added, and a Lewis acid is further added if necessary, and then the polymerization reaction is continued to proceed. At both ends of segment B consisting of ether unit (b), segment A consisting of (protected) vinylphenol unit (a) is synthesized.

Although polymerization conditions of the said polymerization reaction vary with kinds of Lewis acid, a bifunctional initiator, a monomer, a solvent, etc. which are used, the polymerization temperature is preferably in the range of -80 degreeC-150 degreeC normally, -78 degreeC-80 degreeC The range of ° C is more preferable. In addition, polymerization time is the range of 2 hours-100 hours normally.

Deprotection from the copolymer prepared as mentioned above can be performed by making reaction temperature 50-150 degreeC and reaction time 1-30 hours under acidic catalysts, such as hydrochloric acid and a sulfuric acid, in a solvent, for example.

On the other hand, the epoxy resin composition of this invention contains the said phenolic hardening | curing agent and an epoxy resin as an essential component. Specific examples of the epoxy resin used include polycondensates of bisphenols and phenols (phenol, alkyl substituted phenol, naphthol, alkyl substituted naphthol, dihydroxybenzene, dihydroxynaphthalene, etc.) with various aldehydes, phenols and various diene compounds. Glycidyl ether epoxy resin, alicyclic epoxy resin, glycidyl amine epoxy resin, glycidyl which glycidylated the polymer of the compound, the polycondensate of phenols and aromatic dimethylol, biphenols, alcohols, etc. Ester epoxy resin etc. can be mentioned, What is generally marketed can be used suitably according to a use.

For example, when using the epoxy resin composition of this invention for the liquid epoxy resin composition which uses for sealing materials for semiconductor packages, uses, such as a conductive adhesive, a die-bonding paste, and an anisotropic conductive paste, it is preferable to use a liquid epoxy resin at normal temperature. desirable. If it is not a liquid at normal temperature, a solvent is required, but it is not preferable because the solvent causes bubbles and lowers the adhesive strength and thermal conductivity of the cured product. In addition, in the present specification, the epoxy resin that is liquid at room temperature is not only liquid form at room temperature, but, for example, even if it is solid at room temperature, the liquid resin is stably displayed at room temperature by mixing with the liquid epoxy resin at room temperature. Include.

Examples of the liquid epoxy resin at room temperature include bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol AD diglycidyl ether and naphthalene diol di Alicyclic epoxy resins such as glycidyl ether, 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxycyclohexane carboxylate and vinylcyclohexene diepoxide, and diglyes of bisphenol A ethylene oxide adducts Diglycidyl ether, diglycidyl ether of bisphenol A propylene oxide adduct, cyclohexane dimethanol diglycidyl ether, polyglycidyl ether of polyhydric alcohol, and diglycidyl of hexahydrophthalic anhydride And polyglycidyl esters of polybasic acids such as tere. An epoxy resin may be used individually by 1 type, and may use 2 or more types together.

Although it will not specifically limit as a compounding ratio of an epoxy resin and a phenolic hardening | curing agent, Usually, a phenolic hardening | curing agent is 50-200 mass parts with respect to 100 mass parts of epoxy resins.

In addition to the phenolic curing agent of the present invention, other curing agents can be used for the epoxy resin composition of the present invention within a range that does not impair performance. As the curing agent, an amine compound, an acid anhydride compound, an amide compound, a phenol compound or the like can be used. As a specific example of the hardening | curing agent which can be used, diamino diphenylmethane, diethyl lentriamine, triethylene tetramine, diamino diphenyl sulfone, isophorone diamine, dicyandiamide, the dimer of linoleic acid, and ethylenediamine Polyamide resin, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic acid anhydride, hexahydrophthalic anhydride, methylhexahydroanhydride synthesized by Phthalic acid, bisphenols, phenols (phenol, alkyl substituted phenol, naphthol, alkyl substituted naphthol, dihydroxybenzene, dihydroxynaphthalene, etc.) and polycondensates of various aldehydes, phenols and polymers of various diene compounds, phenols and Polycondensates with aromatic dimethylol, biphenols and their modified products, oxis And the like Irene compounds or their polymers.

Moreover, you may use a hardening accelerator together in the epoxy resin composition of this invention. As a specific example of a hardening accelerator, imidazole, such as 2-methylimidazole, 2-ethylimidazole, and 2-ethyl-4-methylimidazole; Tertiary amines such as 2- (dimethylaminomethyl) phenol and 1,8-diaza-bicyclo (5,4,0) undecene-7; Phosphines, such as triphenylphosphine; Metal compounds, such as octylic acid tin, etc. are mentioned. A hardening accelerator can be normally used in 0.01-15 mass parts as needed with respect to 100 mass parts of epoxy resins.

In the case where the epoxy resin contained in the epoxy resin of the present invention and the phenolic curing agent of the present invention are liquid at room temperature, it is not necessary to use a solvent, but a solvent may be blended as necessary in order to adjust the viscosity, coatability, and the like. . As the solvent, for example, a known solvent such as an alcohol solvent, an ester solvent, an ether solvent, a ketone solvent, a hydrocarbon solvent, or a fatty acid solvent is used. Specifically, toluene, xylene, tetrahydrofuran, acetone, methyl ethyl ketone, methyl isobutyl ketone, 2-hexanone, 2-heptanone, ethyl carbitol acetate, butyl carbitol acetate, butyl carbye Organic solvents such as tall, butyl cellosolve, butyl cellosolve acetate, propylene glycol monomethyl ether acetate, triethylene glycol monobutyl ether, and the like, but are not limited thereto.

Moreover, fillers, such as a silica, aluminum oxide, talc, silver powder, various compounding agents, such as a silane coupling agent, a mold release agent, and a pigment, can be added to the epoxy resin composition of this invention as needed.

Although the hardening conditions of the epoxy resin composition of this invention are not restrict | limited especially, Depending on the use of hardened | cured material, it can heat about 10 minutes-about 48 hours, for example at the temperature of 50-200 degreeC, and can harden a composition. Moreover, in order to fully advance hardening or to prevent foam | bubble generation, you may heat in two steps, For example, in a 1st step, it heats at a temperature of 50-150 degreeC for about 10 minutes-10 hours, Furthermore, It can also harden by heating at a temperature of 100-200 degreeC for about 30 to 12 hours. In practical terms, the curing temperature and the curing time are determined in consideration of the productivity, the cured product properties obtained, and the like.

Example

Although a synthesis example, an Example, a comparative example, and a test example are given to the following, this invention is further demonstrated, but this invention is not limited to these Examples at all. In addition, the physical property evaluation of the copolymer obtained in the synthesis example was performed with the following method.

Average Copolymer Composition:

^It calculated | required from the measurement result of ^13C -NMR.

Weight average molecular weight Mw and molecular weight distribution Mw / Mn:

Obtained from standard polystyrene calibration curve by gel permeation chromatography (GPC) method [RI detector: column: KF-801 + KF-805L available from Shodex; Eluent is tetrahydrofuran].

Viscosity Measurement:

It measured with the Brookfield type rotational viscometer.

Synthesis Example 1

Preparation of p-isopropylphenol / ethylvinylether / p-isopropylphenolic triblock polymer (copolymer 1):

The glass container to which the 3-way stopcock was attached was prepared, and after argon substitution, it heated under argon atmosphere and the adsorbed water in a glass container was removed. 252.6 g of ethyl vinyl ether (hereinafter referred to as "EVE"), 280 g of ethyl acetate, 9.4 g of 1,4-bis (1-acetoxyethoxy) butane and 2640 g of toluene were added to the vessel. When the temperature was reached, 68 ml of 0.91 mol of Et _1.5 AlCl _1.5 (hereinafter referred to as “M”) / L toluene solution was added to initiate polymerization. The conversion of EVE was monitored by time division using gas chromatography (GC), and 21.2 g of p-isopropylphenol (hereinafter referred to as "PIPP") was added to the reaction solution at the end of conversion of the EVE monomer. The reaction continued further.

After 2.5 hours and 5 hours after the addition of PIPP, ₄ mL and 2 mL of 0.5 M / L toluene solution of SnCl ₄ were added, respectively. The reaction was terminated 5.5 hours after PIPP addition. 100 ml of a 1 M / L NH ₃ methanol solution was added to the polymerization reaction system to stop the reaction. 4 mass% of aluminum oxide was added to the reaction mixture solution, followed by stirring for 24 hours to adsorb and remove the catalyst. Aluminum oxide was removed. The filtrate was concentrated under reduced pressure in an evaporator to obtain a PIPP / EVE / PIPP-based triblock polymer (copolymer 1).

The average composition of the obtained copolymer 1 was PIPP / EVE = 4.3 / 95.7. In addition, the weight average molecular weight Mw was 17800, the number average molecular weight Mn was 13300, and the molecular weight distribution Mw / Mn was 1.34. In addition, the viscosity in 50 degreeC was 52400 mPa * s.

Synthesis Example 2

Preparation of p-isopropylphenol / ethylvinylether / p-isopropylphenolic triblock polymer (copolymer 2):

The glass container with a 3-way stopper was prepared, and after argon substitution, it heated under argon atmosphere and removed the adsorption water in a glass container. Into a container, 252.6 g of EVE, 280 g of ethyl acetate, 9.4 g of 1,4-bis (1-acetoxyethoxy) butane and 2640 g of toluene were added, and 0.91 M / of Et _1.5 AlCl _1.5 when the system temperature reached 0 ° C. 68 ml of a toluene solution was added to start the polymerization. The conversion of EVE was monitored by time chromatography using gas chromatography (GC), and 28.4 g of PIPP was added to the reaction solution at the end of conversion of the EVE monomer to further maintain the reaction.

After 2.5 hours after the addition of PIPP, 14 ml of a 0.5 M / L toluene solution of SnCl ₄ was added. The reaction was terminated 6 hours after PIPP addition. 100 ml of a 1 M / L NH ₃ methanol solution was added to the polymerization reaction system to stop the reaction. 4 mass% of aluminum oxide was added to the reaction mixture solution, followed by stirring for 24 hours to adsorb and remove the catalyst. Aluminum oxide was removed. The filtrate was concentrated under reduced pressure in an evaporator to obtain a PIPP / EVE / PIPP-based triblock polymer (copolymer 2).

The average composition of the obtained copolymer 2 was PIPP / EVE = 5.7 / 94.3. In addition, the weight average molecular weight Mw was 12800, the number average molecular weight Mn was 10400, and the molecular weight distribution Mw / Mn was 1.23. In addition, the viscosity in 50 degreeC was 36000 mPa * s.

Example 1

As the epoxy resin, 100 parts by mass of bisphenol A-type epoxy resin (EPICLON850s; manufactured by DIC Corporation) and 1.66 parts by mass of the copolymer prepared in Synthesis Example 1 as a phenolic curing agent were mixed to obtain an epoxy resin composition (1a).

Next, to this epoxy resin composition (1a), 1 part by mass of 2-ethyl-4-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) and 70 parts by mass of tetrahydrofuran as a solvent were added to the epoxy resin composition ( 1b), it apply | coated on SUS304 board, heat-processed at 150 degreeC for 2 hours, and 180 degreeC for 5 hours in dryer, and obtained hardened | cured material.

Example 2

In Example 1, the epoxy resin compositions (2a) and (2b) were obtained in the same manner as in Example 1 except that Polymer 2 prepared in Synthesis Example 2 was used as the phenol-based curing agent.

Comparative Example 1

In Example 1, an epoxy resin composition was prepared in the same manner as in Example 1 except that polyvinylphenol resin (Maruka LYNCUR S-2: Maruzen Petrochemical Co., Ltd.) was used as the phenol-based curing agent. 3a) and (3b) were obtained.

Test Example 1

About the epoxy resin compositions (1a), (2a), and (3a) obtained in Example 1, Example 2, and Comparative Example 1, the viscosity of 50 degreeC and 150 degreeC was measured with the Brookfield-type rotational viscometer. The results are shown in Table 1.

Example 1 Example 2 Comparative Example 1 Resin composition 1a 2a 3a  Formulation (parts by mass) Epoxy resin EPICLON850s 100 100 100 Phenolic Curing Agent Copolymer 1 Copolymer 2 Maruca Linker S-2 66  66   66 Viscosity (m㎩s) 50 ℃ 3010 2290 16700 150 ℃ 22.9 9.8 314

As is clear from Table 1, the epoxy resin compositions (1a) and (2a) of Examples 1 and 2 using the phenolic curing agent according to the present invention are the epoxy resin composition (3a) of Comparative Example 1 using polyvinylphenol and In comparison, the viscosity at 50 ° C. is low, and when the filler is not used, it can be used as a solvent-free and the amount of solvent can be reduced even when the filler is used.

In Comparative Example 1, the viscosity of the epoxy composition (3a) at 150 ° C exceeds 300 mPa · s, whereas in the epoxy compositions (1a) and (2a) of Examples 1 and 2, 100 mPa · s The low value below is shown, and even in the molten state until hardening, it reaches | attains reaching the low viscosity fully followed by a to-be-adhered surface at a lower temperature. Therefore, also in hardening at lower temperature, it is suggested that the hardened | cured material excellent in adhesiveness with a to-be-adhered surface is obtained.

Test Example 2

In Example 1, Example 2, and the comparative example 1, the following characteristics were evaluated about the hardened | cured material obtained from the epoxy resin composition (1b), (2b), and (3b), respectively. The results are shown in Table 2.

<Characteristic and measuring method>

Glass transition temperature:

Pyris 1 DSC (input compensation) from PerkinElmer, Inc., measured at a heating rate of 10 ° C / min

5% weight loss temperature:

Pyris 1 TGA from PerkinElmer measured at a rate of 10 ° C / min

Hardness test:

Evaluation by pencil hardness test by mechanical method

Contact Test:

We evaluate by the check tape method

Example 1 Example 2 Comparative Example 1 Resin composition 1b 2b 3b Formulation (parts by mass) Epoxy resin EPICLON850s 100 100 100 Phenolic Curing Agent Copolymer 1 Copolymer 2 Maruca Linker S-2 66  66   66 Reaction accelerator 2-ethyl-4-methylimidazole One One One solvent Tetrahydrofuran 70 70 70 Cured Product Properties Glass transition temperature (℃) 23 187 -32 211  211 5% weight loss temperature (℃) 346 344 367 Pencil hardness 2H 2H 2H Checkerboard 100/100 91/100 6/100

In addition, as is apparent from Table 2, the cured product obtained from the epoxy resin compositions (1b) and (2b) of Examples 1 and 2 has a glass transition point derived from a vinyl ether unit below room temperature, and has a vinyl ether unit. It shows that the phase derived from fine phase-separates in hardened | cured material. Therefore, the elasticity modulus of hardened | cured material falls, and the thermal stress relaxation characteristic of hardened | cured material can be improved.

On the other hand, the change in elastic modulus under high temperature of the cured product is controlled by the phase derived from the crosslinked product of the epoxy resin and the vinylphenol unit, but the room temperature of the cured product obtained in the epoxy resin compositions (1b) and (2b) of Examples 1 and 2 The glass transition temperature and the 5% weight loss temperature at a higher temperature are about the same or somewhat lower than those of the cured product obtained in the epoxy resin composition (3b) of Comparative Example 1 using polyvinylphenol, and are inferior in practical use. It has no heat resistance. Moreover, it is excellent also in hardness and adhesiveness, and can be used suitably in uses, such as an electrical / electronic field and a coating composition.

Examples 3-6 and Comparative Examples 2-3

Resin compositions (4b) to (9b) were prepared in the same manner as in Example 1 in the formulations shown in Table 3, and the cured product physical properties were measured. The results are shown in Table 3.

Example 3 Example 4 Example 5 Example 6 Comparative Example 2 Comparative Example 3 Resin composition 4b 5b 6b 7b 8b 9b Formulation (parts by mass) Epoxy resin EPICLON850s EPICLON1055 EPICLON EXA-4850-150 100 100 100 100 100 100 Phenolic Curing Agent Copolymer 2 Maruka Linker S-2 66 66 53 13 40 26 66 66 Reaction accelerator 2-ethyl-4-methylimidazole One One One One One One solvent Tetrahydrofuran 100 70 70 70 100 100 Cured Product Glass transition temperature (℃) -39 111 -26 128 -38 210 -24 210 133 98 5% weight loss temperature (℃) 360 286 360 366 377 280 Pencil hardness 3H 2H 3H 3H 3H 2H Checkerboard 98/100 100/100 100/100 100/100 74/100 75/100 EPICLON850s: Bisphenol A epoxy resin from DIC Corporation EPICLON1055: Bisphenol A epoxy resin from DIC Corporation EPICLON EXA-4850-150: Bisphenol A modified epoxy resin from DIC Corporation

As is apparent from Table 3, also in the epoxy resin compositions (epoxy resin compositions (4b) and (5b)) in which the epoxy resin was changed, the epoxy resin (epoxy resin composition (6b) using the polymer of the present invention and polyvinylphenol in combination. Also in () and (7b)), hardened | cured material substantially the same as the epoxy resins 1b and 2b of Example 1 and 2 was obtained.

The epoxy resin composition incorporating the polyvinyl phenol-based curing agent of the present invention has fluidity even at a low temperature, and can be cured at a low temperature as compared with the epoxy resin composition containing a conventional polyvinyl phenol. In addition, it has good applicability and filling property in a solvent-free or less solvent amount. Moreover, while the hardened | cured material obtained is a thing with favorable heat resistance, it is possible to improve a thermal stress relaxation characteristic.

Therefore, the polyvinyl phenol type hardening | curing agent of this invention and the epoxy resin composition which mix | blended this can be used advantageously in the fields of electrical and electronic fields, coating composition, etc.

Claims (5)

A phenolic curing agent used as a curing agent for epoxy resins, comprising a vinylphenol unit (a) represented by the following formula (1) and a vinyl ether unit (b) represented by the formula (2) below, wherein Phenolic curing agent, characterized in that the copolymer having two or more hydroxyl groups: [Formula 1]

(Wherein R ₁ represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms and n represents 1 or 2) [Formula 2]

[In formula, R <_2> is a C1-C6 linear or branched alkyl group, a C1-C6 linear or branched fluoroalkyl group, a C5-C10 cycloalkyl group, or the aryl group represented by following General formula (3). Or an arylalkyl group: [Formula 3]

(Wherein m is 0, 1, 2 or 3, X is an unsubstituted phenyl group or one or more linear or branched alkyl groups having 1 to 4 carbon atoms, linear or branched fluoroalkyl groups having 1 to 4 carbon atoms) , An alkoxy group having 1 to 4 carbon atoms or a phenyl group substituted with a halogen atom). The phenolic curing agent according to claim 1, wherein the copolymer forms an ABA-type triblock having a vinylphenol unit (a) as an A segment and a vinyl ether unit (b) as a B segment. The phenolic curing agent according to claim 1 or 2, wherein the molar composition ratio of the vinylphenol unit (a) and the vinyl ether unit (b) in the copolymer is 1/99 to 10/90. The phenolic curing agent according to claim 1 or 2, wherein the copolymer has a viscosity of 100000 mPa · s or less at 50 ° C. The epoxy resin composition containing the phenolic hardening | curing agent and epoxy resin of Claim 1 or 2.