JP2023048208A - Block copolymer and method for producing the same - Google Patents

Abstract

To provide a silicone-based block copolymer which achieves high toughness in addition to low elastic modulus of a resin cured product when mixed with an epoxy resin and to provide a method for producing the same.SOLUTION: There are provided: a block copolymer containing [A] a block composed of polysiloxane, [B] a block composed of polyalkylene glycol and [C] a linkage segment, wherein the linkage segment [C] has an epoxy group and contains an ester bond and/or an amide bond and the block copolymer has an epoxy group content of 0.1 to 3.0 mmol/mg and a weight average molecular weight of 5000 to 500000; and a method for producing the same.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a silicone-based block copolymer and a method for producing the same.

Packaging technology for mounting semiconductors in electronic devices continues to evolve, and packages with complex forms in which semiconductor chips are stacked three-dimensionally are being developed. A sealing material, which is a constituent material of a semiconductor package, plays a role in protecting the internal semiconductor from impact, dust, etc., and generally consists of an epoxy resin, a curing agent, a cured filler, and a low-stress agent. A low-stress agent is added to avoid damage to the package due to cracks and warpage by reducing the elastic modulus of the encapsulant, and a polymer whose main component is silicone, which has a low elastic modulus, is generally used. . However, since silicone has a low affinity with epoxy resins and is difficult to mix with, a technique using an ABA-type triblock copolymer in which polyalkylene glycol chains, which have a high affinity with epoxy, are bound to both ends of silicone has been disclosed. (Patent Document 1). Further, a technique is disclosed in which an epoxy group is introduced into silicone to facilitate mixing by designing it so that it can react with a curing agent in the same manner as epoxy resin (Patent Document 2).

JP-A-10-182831 JP-A-4-359023

With the development of semiconductor packaging technology, in addition to the above-mentioned demand for a low modulus of elasticity, there is an increasing demand for a toughness of the encapsulating material for the purpose of preventing cracks occurring in the encapsulating material from extending.

The silicone-based block copolymer of Patent Document 1 has insufficient affinity with the resin, and although the affinity is improved in Patent Document 2, there are few reaction points with the resin. There was a problem with effectiveness.

An object of the present invention is to provide a silicone-based block copolymer that, when mixed with an epoxy resin, achieves a cured resin having a low elastic modulus and a high toughness, and a method for producing the same.

In order to solve the above problems, the present inventors made intensive studies, and as a result, arrived at the following invention. That is, the present invention
"<1> A block copolymer containing block [A], block [B], and connecting segment [C], wherein block [A] has a structural unit represented by general formula (1),

(R ₁ represents hydrogen, an alkyl group having 1 to 10 carbon atoms or an aryl group, which may be the same or different, and n represents a repeating unit of 5 to 70.)
Block [B] has a structural unit represented by general formula (2),

(R ₂ represents an alkylene group or an arylene group having 1 to 10 carbon atoms, which may be the same or different. m represents a repeating unit of 3 to 100.)
The connecting segment [C] has an epoxy group and contains an ester bond and/or an amide bond, the epoxy group content of the block copolymer is 0.1 to 3.0 mmol/g, and the weight average molecular weight is A block copolymer of 5,000 to 500,000.
<2> A compound [A'] having a structural unit represented by the general formula (1) and having at both ends any functional group selected from a hydroxyl group and an amino group, and the general formula (2) and a compound [B'] having at both ends any functional group selected from a hydroxyl group and an amino group, and a linkage having two or more carboxylic anhydride groups in the molecule The agent [C1′] is reacted to obtain a block copolymer intermediate, and in the presence of a catalyst, a compound having two or more epoxy groups in the molecule [ C2′] is reacted to produce the block copolymer described above.
<3> An epoxy resin composition containing the above block copolymer and an epoxy resin.
<4> A cured epoxy resin obtained by curing the above epoxy resin composition. ”.

ADVANTAGE OF THE INVENTION According to this invention, the silicone type block copolymer which can make an epoxy-resin hardened|cured material low elastic modulus, and high toughness, and its manufacturing method can be provided.

The block copolymer in the present invention consists of a structure containing block [A], block [B] and connecting segment [C].

Here, the block [A] of the present invention has a polysiloxane structural unit represented by general formula (1). Since such a structural unit has a siloxane skeleton, a cured resin product (molded product) containing a block copolymer has improved mechanical properties such as durability, toughness and elastic modulus.

R ₁ in general formula (1) represents hydrogen, an alkyl group having 1 to 10 carbon atoms, or a phenyl group, and may be the same or different. _R1 is preferably a methyl group, an ethyl group, or a propyl group, more preferably a methyl group, from the viewpoint that the elastic modulus of the cured resin can be reduced.

n represents the number of repeating units from 5 to 70; The lower limit of the repeating unit n is preferably 7 or more, more preferably 10 or more, and particularly preferably 12 or more, from the viewpoint of reducing the elastic modulus of the cured resin. In addition, the upper limit of the repeating unit n is preferably 60 or less, more preferably 55 or less, and particularly preferably 50 or less, from the viewpoint of good dispersion in the cured resin and improvement in strain at break.

Block [B] in the present invention has a polyalkylene glycol structural unit represented by general formula (2). Such a structural unit has a high affinity with the resin and has good dispersibility in the resin composition, thereby improving mechanical properties such as toughness of the molded article.

R ₂ represents an alkylene group having 2 to 10 carbon atoms or an arylene group, which may be the same or different. The number of carbon atoms in R ₂ is preferably 3 or 4 from the viewpoint of improving the strain at break.

m represents the number of repeating units from 3 to 100. The lower limit of the repeating unit m is preferably 5 or more, more preferably 7 or more, and particularly preferably 10 or more, from the viewpoint of improving the strain at break. Moreover, the upper limit of the repeating unit n is preferably 90 or less, more preferably 80 or less, and particularly preferably 70 or less, from the viewpoint of reducing the elastic modulus of the cured resin.

The connecting segment [C] in the present invention is a connecting portion that connects block [A] and block [B], has an epoxy group, and contains an ester bond and/or an amide bond. Since such a connecting part has an epoxy group that reacts in the resin, the affinity of the block copolymer with the resin is increased, and mechanical properties such as toughness of the molded article are improved.

The connecting segment [C] in the present invention is preferably represented by general formulas (3) and/or (4). X in general formulas (3) and (4) represents —O— or —NH— and may be the same or different. X is preferably -O- because the elastic modulus of the cured resin is lowered. Y represents an organic group having 4 to 14 carbon atoms and may be the same or different. The preferable number of carbon atoms of Y is preferably 6 or 12 from the viewpoint of good dispersion in the resin cured product and improvement of strain at break. Z represents an organic group containing an epoxy group and may be the same or different. R ₃ represents an organic group having 1 to 7 carbon atoms, may contain an amide group, and may be the same or different. R ₃ is preferably an organic group having an amide group having 4 to 7 carbon atoms, more preferably an organic group having an amide group having 4 or 5 carbon atoms, from the viewpoint of improving the strain at break.

Y in general formulas (3) and/or (4) is preferably at least one structure selected from general formulas (5) to (13). It is more preferable that Y has a structure represented by (5) or (9) from the viewpoint of good dispersion in the cured resin and improvement in strain at break.

Z in general formulas (3) and/or (4) is preferably at least one structure selected from general formulas (14) and (15).

R ₄ in general formula (14) represents an alkylene group having 2 to 10 carbon atoms. The carbon number of R ₄ is preferably 2 to 5, more preferably 2 or 3, since the elastic modulus of the cured resin to which the block copolymer is added is lowered. l represents 1 to 40 repeating units. The range of the repeating unit l is preferably 1 to 30, more preferably 1 to 20, still more preferably 1 to 10, and particularly preferably 1 to 5, from the viewpoint of reducing the elastic modulus of the cured resin.

R ₅ in general formula (15) represents hydrogen or a methyl group, and k represents 0 to 10 repeating units. The range of the repeating unit k is preferably 0 to 7, more preferably 0 to 5, and particularly preferably 0 to 3, from the viewpoint of reducing the elastic modulus of the cured resin.

The epoxy group content of the block copolymer in the present invention should be in the range of 0.1 to 3.0 mmol/g from the viewpoint of improving the affinity with the resin. If the carboxyl group content is less than 0.1 mmol/g, the number of reaction points with the resin decreases, the affinity with the resin decreases, and the toughness and interfacial adhesiveness of the obtained molded article decrease. The lower limit of the carboxyl group is more preferably 0.2 mmol/g or more, particularly preferably 0.3 mmol/g or more. If the epoxy group content exceeds 3.0 mmol/g, when such a block copolymer is blended into a resin, the reaction proceeds excessively due to the large number of reaction points, and the elastic modulus of the resin composition decreases. increase and liquidity decrease. The upper limit of the epoxy group is more preferably 2.5 mmol/g or less, still more preferably 2.0 mmol/g or less, and particularly preferably 1.5 mmol/g or less.

The epoxy group content of such a block copolymer can be calculated by a method according to JISK7236 (2009).

The weight average molecular weight (M _w ) of the block copolymer of the present invention is preferably in the range of 5,000 or more and 500,000 or less. If the weight-average molecular weight is less than 5,000, the toughness of the block copolymer is low, and the toughness of the molded product may be low. The lower limit of the weight average molecular weight is preferably 5,000 or more, more preferably 7,000 or more, and particularly preferably 10,000 or more. On the other hand, when the weight average molecular weight is more than 500,000, the viscosity of the block copolymer tends to increase and the fluidity tends to deteriorate. Furthermore, when obtaining a molded product in which the block copolymer is blended with the resin, it is not possible to permeate into the details of the mold during molding, which causes molding defects, which is not preferable. The upper limit of the weight average molecular weight is preferably 200,000 or less, more preferably 100,000 or less, and particularly preferably 50,000 or less.

The weight average molecular weight of the block copolymer referred to here refers to the weight average molecular weight measured by gel permeation chromatography using tetrahydrofuran (THF) as a solvent and converted to polymethyl methacrylate.

The content of the structure derived from block [A] in the block copolymer of the present invention is preferably 10% by mass or more and 90% by mass or less based on 100% by mass of the entire block copolymer. The lower limit of the content is preferably 10% by mass or more, more preferably 15% by mass or more, and particularly preferably 20% by mass or more. The upper limit of the content is preferably 80% by mass or less, more preferably 70% by mass or less, and particularly preferably 60% by mass or less. When the content of the structure derived from block [A] is too small, even if the block copolymer is added to the epoxy resin to prepare a cured product, the addition of the block copolymer has a low effect of lowering the elastic modulus. In addition, when the content of the structure derived from block [A] is too large, when the block copolymer is added to the epoxy resin, the block copolymer cannot be well dispersed in the epoxy resin cured product, and the breaking point strain worsens.

The content of the structure derived from block [A] in the block copolymer in the present invention is determined by ¹ H NMR measurement of the block copolymer, and the signal intensity derived from block [A], block [B] and connecting segment [C] is a value obtained by calculating the ratio of the mass of the structure derived from block [A] to the mass of the entire block copolymer.

The method for producing a block copolymer in the present invention comprises a compound [A' ] And a compound [B′] having a structural unit represented by the general formula (2) and having at both ends any functional group selected from a hydroxyl group and an amino group, and the general formula (5) to obtain a block copolymer intermediate by reacting a linking agent [C1′] having a structural unit represented by (13) and having two or more carboxylic anhydride groups in the molecule, and a catalyst A method of reacting a compound [C2′] having two or more epoxy groups in the molecule in an amount of 5 to 50 times the moles of [C1′] in the presence of is preferred.

The compound [A'] has a structural unit represented by the general formula (1) and has at its end a functional group selected from a hydroxyl group and an amino group, and reduces the elastic modulus of the cured resin. A hydroxyl group is preferable as the functional group because it can be

The weight average molecular weight of compound [A'] is not particularly limited, but the lower limit is preferably 500 or more, more preferably 800 or more, and still more preferably 1,000 or more. The upper limit of the weight average molecular weight is preferably 8,000 or less, more preferably 5,000 or less, still more preferably 4,000 or less, and most preferably 3,000 or less. When the weight-average molecular weight of the compound [A'] having a terminal functional group selected from a hydroxyl group and an amino group is small, the properties derived from the silicone skeleton are not exhibited, and the resulting block copolymer is used as an epoxy resin. Since the performance as a resin modifier at the time of addition may become low, it is not preferable. In addition, when the weight average molecular weight of compound [A'] is large, compound [A'] and compound [B'] undergo phase separation, polymerization does not proceed in a uniform state, and a homogeneous block copolymer is obtained. It is not preferable from the viewpoint that the strain at break is reduced. The weight average molecular weight of compound [A'] refers to the weight average molecular weight measured by gel permeation chromatography using tetrahydrofuran (THF) as a solvent and converted to polymethyl methacrylate.

Compound [A'] is commercially available from Shin-Etsu Chemical Co., Ltd., KF-6000, KF-6001, KF-6002, KF-6003, X-22-160AS, X-22-1821, PAM-E , KF-8010, X-22-161A, X-22-161B, KF-8012, KF-8008, X-22-1660B-3, X-22-9409, commercially available from Dow Corning Toray Co., Ltd. , BY16-201, SF8427 Fluid, BY16-853U, BY16-871 and the like.

The compound [B'] has a structural unit represented by the general formula (2), and has at the end a functional group selected from a hydroxyl group and an amino group, and reduces the elastic modulus of the cured resin. A hydroxyl group is preferable as the functional group because it can be

The weight average molecular weight of compound [B'] is not particularly limited, but the lower limit is preferably 400 or more, more preferably 800 or more, and still more preferably 1,000 or more. The upper limit of the weight average molecular weight is preferably 8,000 or less, more preferably 5,000 or less, still more preferably 4,000 or less, and most preferably 3,000 or less. If the weight-average molecular weight of the compound [B'] is small, the performance as a resin modifier when the resulting block copolymer is added to an epoxy resin may be lowered, which is not preferred. Further, when the weight average molecular weight of the compound [B'] is large, the compound [B'] and the compound [A'] undergo phase separation, polymerization does not proceed in a uniform state, and a homogeneous block copolymer is obtained. It is not preferable from the viewpoint that the strain at break is reduced. The weight average molecular weight of compound [B'] refers to the weight average molecular weight measured by gel permeation chromatography using tetrahydrofuran (THF) as a solvent and converted to polymethyl methacrylate.

Compound [B'] has a structural unit represented by the general formula (2). Specifically, polyneopentyl glycol in which _R2 is a branched pentene group, polytetramethylene glycol in which _R2 is a linear butylene group, polypropylene glycol in which _R2 is a branched propylene group, and _R2 is an ethylene group. and copolymers thereof. In particular, polyneopentyl glycol, polytetramethylene glycol, polypropylene glycol, and polypropylene glycol/polyethylene glycol copolymer are preferable because they have excellent affinity with compound [A'] and can yield a homogeneous block copolymer. , polytetramethylene glycol, polypropylene glycol, and polypropylene glycol/polyethylene glycol copolymer are more preferable, and polypropylene glycol is particularly preferable, because of their excellent affinity with other polymer components.

The linking agent [C1'] is a compound having structural units represented by general formulas (5) to (13) and two or more carboxylic anhydride groups in the molecule. Specifically, pyromellitic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,3,3′,4′-biphenyltetracarboxylic dianhydride, 2, 2′,3,3′-biphenyltetracarboxylic dianhydride, 3,3′,4,4′-diphenylethertetracarboxylic dianhydride, 4,4′-oxydiphthalic anhydride, 1,3,3a, 4,5,9b-hexahydro-5(tetrahydro-2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride , 1,2,4,5-cyclohexanetetracarboxylic dianhydride. In particular, pyromellitic dianhydride, 1,3,3a,4,5,9b-hexahydro-5 (tetrahydro -2,5-dioxo-3-furanyl)naphtho[1,2-c]furan-1,3-dione is preferred.

Results of reaction between the hydroxyl group or amino group of compound [A'] and the acid anhydride group of linking agent [C1'], and the hydroxyl group or amino group of compound [B'] and the acid anhydride group of linking agent [C1'] , an ester bond or an amide bond and a carboxyl group are generated. Therefore, the block copolymer intermediate has a carboxyl group at the linkage.

The carboxyl group content of such a block copolymer intermediate was measured according to JISK0070 (1992) by dissolving the block copolymer in tetrahydrofuran and adding 0.1 mol/L alcoholic potassium hydroxide with phenolphthalein as an indicator. It can be sum titrated and calculated.

As a method of obtaining a block copolymer intermediate by reacting compound [A'], compound [B'], and linking agent [C1'], compound [A'], compound [B'], and linking agent A method of mixing [C1′] and heating to cause a reaction can be exemplified. If necessary, the reaction may be carried out using an organic solvent or under a nitrogen atmosphere, or may be carried out under reduced pressure in order to promote the reaction. A reaction accelerator or the like may be added during the reaction, but it is preferable to carry out the reaction without using a reaction accelerator, since there is a possibility of promoting side reactions.

In the method for producing the block copolymer of the present invention, the ratio of the number of moles of the linking agent [C1′] to the sum of the moles of the compound [A′] and the compound [B′] is appropriately adjusted from 0.5 to 1.2. can do

Further, by reacting a part of the carboxyl groups of the block copolymer intermediate with a compound having reactivity with the carboxyl groups, it is possible to control the carboxyl group content to a desired level. This reaction creates a substituent containing an ester bond by blocking the carboxyl group. Specific examples of compounds having reactivity with carboxyl groups (carboxyl group blocking agents) include orthoesters and oxazolines.

Next, the block copolymer intermediate thus obtained is reacted with a compound [C2′] having two or more epoxy groups in the molecule to obtain a composition containing the block copolymer of the present invention. get things As a result of this reaction, the carboxyl group of the block copolymer intermediate reacts with one of the epoxy groups of the compound [C2'] to form an ester bond, and the other epoxy group becomes unreacted to form a side chain. A block copolymer containing epoxy groups is obtained.

The compound [C2′] having two or more epoxy groups in the molecule is not particularly limited as long as it has two or more epoxy groups in the molecule. For example, a compound having a hydroxyl group and epichlorohydrin The obtained glycidyl ether type epoxy compound, the glycidyl amine type epoxy compound obtained from a compound having an amino group and epichlorohydrin, the glycidyl ester type epoxy compound obtained from a compound having a carboxyl group and epichlorohydrin, and the double bond An alicyclic epoxy compound obtained by oxidizing a compound having an epoxy compound, or an epoxy compound in which two or more types selected from these are mixed in the molecule, or the like is used.

Specific examples of glycidyl ether type epoxy compounds include alkylene glycol type epoxy resins obtained by reacting alkylene glycol or its polymer with epichlorohydrin, and bisphenol A type epoxy resins obtained by reacting bisphenol A and epichlorohydrin. , bisphenol F type epoxy resin obtained by reaction of bisphenol F and epichlorohydrin, bisphenol S type epoxy resin obtained by reaction of 4,4'-dihydroxydiphenylsulfone and epichlorohydrin, 4,4'-biphenol and Biphenyl-type epoxy resin obtained by reaction with epichlorohydrin, resorcinol-type epoxy resin obtained by reaction of resorcinol and epichlorohydrin, phenol novolac-type epoxy resin obtained by reaction of phenol and epichlorohydrin, and other polyethylene Glycol-type epoxy resins, polypropylene glycol-type epoxy resins, positional isomers thereof, alkyl group- or halogen-substituted products thereof can be mentioned.

Examples of the alkylene glycol type epoxy resin include Denacol EX-810, Denacol EX-811, Denacol EX-850, Denacol EX-851, Denacol EX-821, Denacol EX-830, and Denacol, which are commercially available from Nagase ChemteX Corporation. EX-832, Denacol EX-841, Denacol EX-861, Denacol EX-920, Denacol EX-931, Denacol EX-211, Nacol EX-212, commercially available from Sanyo Chemical Industries, Ltd., Glycier PP-300P, etc. is mentioned.

Commercially available bisphenol A epoxy resins include "jER" (registered trademark) 825, "jER" (registered trademark) 826, "jER" (registered trademark) 827, and "jER" (registered trademark) 828 (the above, Mitsubishi Chemical Co., Ltd.), "Epiclon" (registered trademark) 850 (manufactured by DIC Corporation), "Epotote" (registered trademark) YD-128 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), D.I. E. R-331™ (Dow Chemical Company), “Bakelite”™ EPR154, “Bakelite”™ EPR162, “Bakelite”™ EPR172, “Bakelite”™ EPR173, and "Bakelite" (registered trademark) EPR174 (manufactured by Bakelite AG) and the like.

Commercially available bisphenol F type epoxy resins include "jER" (registered trademark) 806, "jER" (registered trademark) 807, "jER" (registered trademark) 1750 (manufactured by Mitsubishi Chemical Corporation), "Epiclon ” (registered trademark) 830 (manufactured by DIC Corporation), “Epotato” (registered trademark) YD-170, “Epototo” (registered trademark) YD-175 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), “Bakelite” (registered Trademark) EPR169 (manufactured by Bakelite AG), "Araldite" (registered trademark) GY281, "Araldite" (registered trademark) GY282, and "Araldite" (registered trademark) GY285 (manufactured by Huntsman Advanced Materials), etc. is mentioned.

Commercial products of biphenyl-type epoxy resins include "jER" (registered trademark) YX4000, "jER" (registered trademark) YX4000K, "jER" (registered trademark) YX4000H, "jER" (registered trademark) YX4000HK (the above, Mitsubishi Chemical Co., Ltd.) and the like.

Commercially available resorcinol epoxy resins include "Denacol" (registered trademark) EX-201 (manufactured by Nagase ChemteX Corporation).

Commercially available phenolic novolac epoxy resins include "jER" (registered trademark) 152, "jER" (registered trademark) 154 (manufactured by Mitsubishi Chemical Corporation), and "Epiclon" (registered trademark) 740 (DIC ( (manufactured by Huntsman Advanced Materials), EPN179, EPN180 (manufactured by Huntsman Advanced Materials).

Specific examples of glycidylamine type epoxy compounds include tetraglycidyldiaminodiphenylmethanes, aminophenol glycidyl compounds, glycidylanilines, and xylenediamine glycidyl compounds.

Commercially available products of tetraglycidyldiaminodiphenylmethanes include "Sumiepoxy" (registered trademark) ELM434 (manufactured by Sumitomo Chemical Co., Ltd.), "Araldite" (registered trademark) MY720, "Araldite" (registered trademark) MY721, "Araldite" ( Registered trademark) MY9512, “Araldite” (registered trademark) MY9612, “Araldite” (registered trademark) MY9634, “Araldite” (registered trademark) MY9663 (manufactured by Huntsman Advanced Materials), “jER” (registered trademark) 604 (Mitsubishi Chemical Co., Ltd.), "Bakelite" (registered trademark) EPR494, "Bakelite" (registered trademark) EPR495, "Bakelite" (registered trademark) EPR496, and "Bakelite" (registered trademark) EPR497 (above, Bakelite manufactured by AG) and the like.

Commercially available glycidyl compounds of aminophenol include "jER" (registered trademark) 630 (manufactured by Mitsubishi Chemical Corporation), "Araldite" (registered trademark) MY0500, and "Araldite" (registered trademark) MY0510 (both from Huntsman Advanced Materials Co., Ltd.), “Sumiepoxy” (registered trademark) ELM120, and “Sumiepoxy” (registered trademark) ELM100 (both of which are manufactured by Sumitomo Chemical Co., Ltd.).

Commercially available glycidylanilines include GAN, GOT (manufactured by Nippon Kayaku Co., Ltd.) and "Bakelite" (registered trademark) EPR493 (manufactured by Bakelite AG).

Glycidyl compounds of xylenediamine include TETRAD-X (registered trademark) (manufactured by Mitsubishi Gas Chemical Company, Inc.).

Specific examples of glycidyl ester type epoxy compounds include diglycidyl phthalate, diglycidyl hexahydrophthalate, diglycidyl isophthalate, diglycidyl dimer, and various isomers thereof.

Examples of commercially available diglycidyl phthalates include "Epomic" (registered trademark) R508 (manufactured by Mitsui Chemicals, Inc.) and "Denacol" (registered trademark) EX-721 (manufactured by Nagase ChemteX Corporation). be done.

Commercial products of diglycidyl hexahydrophthalate include “Epomic” (registered trademark) R540 (manufactured by Mitsui Chemicals, Inc.) and AK-601 (manufactured by Nippon Kayaku Co., Ltd.).

Examples of commercial products of dimer acid diglycidyl ester include "jER" (registered trademark) 871 (manufactured by Mitsubishi Chemical Corporation) and "Epotato" (registered trademark) YD-171 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). be done.

Commercially available alicyclic epoxy compounds include "Celoxide" (registered trademark) 2021P (manufactured by Daicel Corporation), CY179 (manufactured by Huntsman Advanced Materials), and "Celoxide" (registered trademark) 2081 (manufactured by ) manufactured by Daicel), and “Celoxide” (registered trademark) 3000 (manufactured by Daicel Corporation).

Compounds having two or more epoxy groups in the molecule may be used singly or in combination of two or more.

The compound having two or more epoxy groups in the molecule is preferably a compound represented by the structure of general formula (16) or (17).

R ₄ in general formula (16) represents an alkylene group having 2 to 10 carbon atoms. R ₄ preferably has 2 to 5 carbon atoms, more preferably 2 or 3 carbon atoms. l represents 1 to 40 repeating units. The range of repeating unit l is preferably 1 to 30, more preferably 1 to 20, still more preferably 1 to 10, and particularly preferably 1 to 5.

R ₅ in general formula (17) represents hydrogen or a methyl group, and k represents 0 to 10 repeating units. The range of repeating unit k is preferably 0 to 7, more preferably 0 to 5, and particularly preferably 0 to 3.

The amount of the compound [C2′] having two or more epoxy groups in the molecule to be used is 5 to 50 times molar excess with respect to the linking agent [C1′] when synthesizing the block copolymer intermediate. ([C2′]/[C1′]=5 to 50). In addition, since an excessive amount of [C2'] is used with respect to the block copolymer intermediate, the product after the reaction is a composition in which the block copolymer of the present invention and unreacted [C2'] are mixed. Become. If [C2']/[C1'] is less than 5, the cross-linking reaction between polymer molecules becomes significant, which is undesirable because the block copolymer undergoes an extreme increase in molecular weight or gels. Here, the cross-linking between polymer molecules means that the carboxyl group of the block copolymer intermediate reacts with one epoxy group of the compound [C2′], and the other epoxy group reacts with another block copolymer intermediate. It refers to the crosslinked structure that connects polymer molecules, which is formed when reacting with the carboxyl groups of When [C2']/[C1'] is greater than 50, the ratio of the compound [C2'] having two or more epoxy groups in the unreacted molecule is large, so block copolymerization is performed at the desired ratio. It is not preferable because it may not be possible to produce an epoxy resin cured product to which coalescence is added. The range of [C2']/[C1'] is preferably 7 to 40, more preferably 10 to 30.

In particular, in the present invention, the use of a catalyst suppresses intermolecular cross-linking, and a special effect of obtaining a desired block copolymer was found. Although the reason is not clear, it is presumed that the reaction rate increases when the block copolymer intermediate is reacted with the compound [C2'] having two or more epoxy groups in the molecule.

As catalysts, amine compound-based curing accelerators typified by 1,8-diazabicyclo(5.4.0)undecene-7; imidazole compounds typified by 2-methylimidazole and 2-ethyl-4-methylimidazole Curing accelerator: Phosphorus compound-based curing accelerators such as triphenylphosphite can be used. Among them, the phosphorus compound-based curing accelerator is most preferred.

Furthermore, in the present invention, the desired block copolymer can be obtained by suppressing intermolecular cross-linking when the reaction temperature is high. This effect is also presumed to be contributed by the improvement of the reaction rate. Therefore, the reaction temperature for reacting the block copolymer intermediate with the compound [C2′] having two or more epoxy groups in the molecule is preferably 100° C. or higher, more preferably 120° C. or higher. and more preferably 140° C. or higher. Since side reactions such as polymer decomposition and epoxy group cleavage may occur, the upper limit is preferably 220° C. or less, more preferably 200° C. or less.

In the present invention, as described above, the block copolymer intermediate is reacted with a compound [C2′] having two or more epoxy groups in the molecule to obtain the block copolymer of the present invention and the unreacted [C2 '] can be used to prepare an epoxy resin cured product described later, but unreacted [C2'] may be removed from the reaction product with a solvent.

As a method for removing unreacted [C2'] using a solvent, a solvent that dissolves [C2'] but does not dissolve the block copolymer is added to the reaction product, stirred for a certain period of time, and then [C2' ] is removed by centrifugation and decantation, and the remaining solvent is removed under reduced pressure.

The solvent is not particularly limited as long as it dissolves the compound [C2'] having two or more epoxy groups in the molecule and does not dissolve the polymer component. Organic solvents include known methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, ethyl acetate, chloroform, toluene, and the like. Among them, when the water-soluble alkylene glycol type epoxy resin of the general formula (16) is used as [C2'], water is a suitable solvent, and separation from the block copolymer is facilitated, which is preferable.

The amount of solvent used is 1 to 10 times the weight of the reaction product obtained by reacting the block copolymer intermediate with the compound [C2′] having two or more epoxy groups in the molecule. Preferably, 1 to 8 times weight is more preferable, 1 to 6 times weight is more preferable, and 1 to 4 times weight is particularly preferable. If the amount of the solvent used is more than 10 times the weight, it is not preferable because the productivity decreases. If the amount of the solvent used is less than 1-fold weight, the compound [C2'] may not dissolve completely and may not be completely removed, which is not preferred.

The epoxy resin composition of the present invention is a mixture of the epoxy resin described later and the block copolymer of the present invention, and refers to the mixture before curing reaction.

A preferable amount of the block copolymer contained in the epoxy resin composition of the present invention is 0.1 to 50 parts by mass, more preferably 0.1 to 40 parts by mass, based on 100 parts by mass of the epoxy resin. Yes, more preferably 0.5 to 30 parts by mass. By including a block copolymer within this range in the epoxy resin composition, the block copolymer is well dispersed in the epoxy resin cured product obtained by curing the epoxy resin composition, and the elastic modulus is efficiently lowered and the breaking point is reduced. A high toughness effect can be imparted by improving the strain.

It is also possible to use a reaction product of a block copolymer and a compound [C2'] having two or more epoxy groups in the molecule. can be calculated, and the resin composition can be prepared so as to have the above content.

Although the epoxy resin is not particularly limited, for example, a glycidyl ether type epoxy resin obtained from a compound having a hydroxyl group and epichlorohydrin, a glycidylamine type epoxy resin obtained from a compound having an amino group and epichlorohydrin, A glycidyl ester type epoxy resin obtained from a compound having a carboxyl group and epichlorohydrin, an alicyclic epoxy resin obtained by oxidizing a compound having a double bond, or two or more types of groups selected from these. Epoxy resin or the like in which is mixed in the molecule is used.

Specific examples of glycidyl ether type epoxy resins include bisphenol A type epoxy resin obtained by reaction of bisphenol A and epichlorohydrin, bisphenol F type epoxy resin obtained by reaction of bisphenol F and epichlorohydrin, 4, 4. Bisphenol S type epoxy resin obtained by reaction of '-dihydroxydiphenyl sulfone and epichlorohydrin, biphenyl type epoxy resin obtained by reaction of 4,4'-biphenol and epichlorohydrin, resorcinol and epichlorohydrin Resorcinol type epoxy resin obtained by reaction, phenol novolak type epoxy resin obtained by reaction of phenol and epichlorohydrin, other polyethylene glycol type epoxy resin, polypropylene glycol type epoxy resin, and their positional isomers, alkyl groups and halogens Substitutions in can be mentioned.

Commercially available bisphenol A epoxy resins include "jER" (registered trademark) 825, "jER" (registered trademark) 826, "jER" (registered trademark) 827, and "jER" (registered trademark) 828 (the above, Mitsubishi Chemical Co., Ltd.), "Epiclon" (registered trademark) 850 (manufactured by DIC Corporation), "Epotote" (registered trademark) YD-128 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), D.I. E. R-331™ (Dow Chemical Company), “Bakelite”™ EPR154, “Bakelite”™ EPR162, “Bakelite”™ EPR172, “Bakelite”™ EPR173, and "Bakelite" (registered trademark) EPR174 (manufactured by Bakelite AG) and the like.

Commercially available bisphenol F type epoxy resins include "jER" (registered trademark) 806, "jER" (registered trademark) 807, "jER" (registered trademark) 1750 (manufactured by Mitsubishi Chemical Corporation), "Epiclon ” (registered trademark) 830 (manufactured by DIC Corporation), “Epotato” (registered trademark) YD-170, “Epototo” (registered trademark) YD-175 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.), “Bakelite” (registered Trademark) EPR169 (manufactured by Bakelite AG), "Araldite" (registered trademark) GY281, "Araldite" (registered trademark) GY282, and "Araldite" (registered trademark) GY285 (manufactured by Huntsman Advanced Materials), etc. is mentioned.

Commercial products of biphenyl-type epoxy resins include "jER" (registered trademark) YX4000, "jER" (registered trademark) YX4000K, "jER" (registered trademark) YX4000H, "jER" (registered trademark) YX4000HK (the above, Mitsubishi Chemical Co., Ltd.) and the like.

Commercially available resorcinol epoxy resins include "Denacol" (registered trademark) EX-201 (manufactured by Nagase ChemteX Corporation).

Commercially available phenolic novolac epoxy resins include "jER" (registered trademark) 152, "jER" (registered trademark) 154 (manufactured by Mitsubishi Chemical Corporation), and "Epiclon" (registered trademark) 740 (DIC ( (manufactured by Huntsman Advanced Materials), EPN179, EPN180 (manufactured by Huntsman Advanced Materials).

Specific examples of glycidylamine type epoxy resins include tetraglycidyldiaminodiphenylmethanes, aminophenol glycidyl compounds, glycidylanilines, and xylenediamine glycidyl compounds.

Commercially available products of tetraglycidyldiaminodiphenylmethanes include "Sumiepoxy" (registered trademark) ELM434 (manufactured by Sumitomo Chemical Co., Ltd.), "Araldite" (registered trademark) MY720, "Araldite" (registered trademark) MY721, "Araldite" ( Registered trademark) MY9512, “Araldite” (registered trademark) MY9612, “Araldite” (registered trademark) MY9634, “Araldite” (registered trademark) MY9663 (manufactured by Huntsman Advanced Materials), “jER” (registered trademark) 604 (Mitsubishi Chemical Co., Ltd.), "Bakelite" (registered trademark) EPR494, "Bakelite" (registered trademark) EPR495, "Bakelite" (registered trademark) EPR496, and "Bakelite" (registered trademark) EPR497 (above, Bakelite manufactured by AG) and the like.

Commercially available glycidyl compounds of aminophenol include "jER" (registered trademark) 630 (manufactured by Mitsubishi Chemical Corporation), "Araldite" (registered trademark) MY0500, and "Araldite" (registered trademark) MY0510 (both from Huntsman Advanced Materials Co., Ltd.), “Sumiepoxy” (registered trademark) ELM120, and “Sumiepoxy” (registered trademark) ELM100 (both of which are manufactured by Sumitomo Chemical Co., Ltd.).

Commercially available glycidylanilines include GAN, GOT (manufactured by Nippon Kayaku Co., Ltd.) and "Bakelite" (registered trademark) EPR493 (manufactured by Bakelite AG).

Glycidyl compounds of xylenediamine include TETRAD-X (registered trademark) (manufactured by Mitsubishi Gas Chemical Company, Inc.).

Specific examples of the glycidyl ester type epoxy resin include diglycidyl phthalate, diglycidyl hexahydrophthalate, diglycidyl isophthalate, diglycidyl dimer, and various isomers thereof.

Examples of commercially available diglycidyl phthalates include "Epomic" (registered trademark) R508 (manufactured by Mitsui Chemicals, Inc.) and "Denacol" (registered trademark) EX-721 (manufactured by Nagase ChemteX Corporation). be done.

Commercial products of diglycidyl hexahydrophthalate include “Epomic” (registered trademark) R540 (manufactured by Mitsui Chemicals, Inc.) and AK-601 (manufactured by Nippon Kayaku Co., Ltd.).

Examples of commercial products of dimer acid diglycidyl ester include "jER" (registered trademark) 871 (manufactured by Mitsubishi Chemical Corporation) and "Epotato" (registered trademark) YD-171 (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.). be done.

Commercially available alicyclic epoxy resins include "Celoxide" (registered trademark) 2021P (manufactured by Daicel Corporation), CY179 (manufactured by Huntsman Advanced Materials), and "Celoxide" (registered trademark) 2081 (manufactured by ) manufactured by Daicel), and “Celoxide” (registered trademark) 3000 (manufactured by Daicel Corporation).

As the epoxy resin, a resin selected from biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin and bisphenol S type epoxy resin is preferable from the viewpoint of heat resistance, toughness and low reflow property, and biphenyl type epoxy resin. Alternatively, a bisphenol A type epoxy resin is more preferred, and a biphenyl type epoxy resin is even more preferred. The above epoxy resins may be used alone or in combination of two or more.

A curing agent and/or a curing accelerator can be added to the epoxy resin composition.

Epoxy resin curing agents include aliphatic polyamine curing agents such as diethylenetriamine and triethylenetetramine; alicyclic polyamine curing agents such as menzenediamine and isophoronediamine; aromatic polyamine curing agents such as diaminodiphenylmethane and m-phenylenediamine. Curing agents; acid anhydride-based curing agents such as polyamide, modified polyamine, phthalic anhydride, pyromellitic anhydride and trimellitic anhydride; polyphenol-based curing agents such as phenol novolac resins and phenol aralkyl resins; polymercaptan, 2,4 , 6-tris(dimethylaminomethyl)phenol, anionic catalysts such as 2-ethyl-4-methylimidazole and 2-phenyl-4-methylimidazole; cationic catalysts such as boron trifluoride/monoethylamine complex; dicyandiamide, Examples include latent curing agents such as aromatic diazonium salts and molecular sieves.

A curing agent selected from an aromatic amine curing agent, an acid anhydride curing agent and a polyphenol curing agent is preferably used from the standpoint of providing an epoxy resin cured product having particularly excellent mechanical properties.

Specific examples of the aromatic amine curing agent include metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, metaxylylenediamine, diphenyl-p-dianiline, various derivatives such as alkyl-substituted products thereof, and amino group-positioned curing agents. Different isomers are included.

Specific examples of acid anhydride curing agents include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, and tetrahydrophthalic anhydride. acids, hexahydrophthalic anhydride, dodecenyl succinic anhydride, benzophenonetetracarboxylic dianhydride, and the like.

Specific examples of polyphenol-based curing agents include phenol aralkyl resins, 1-naphthol aralkyl resins, o-cresol novolak epoxy resins, dicyclopentadiene phenol resins, terpene phenol resins, and naphthol novolak type resins.

The optimum amount of the curing agent to be added varies depending on the type of epoxy resin and curing agent. It is preferably between ~1.4, more preferably between 0.6 and 1.4. If the equivalent ratio is less than 0.5, the curing reaction may not occur sufficiently, resulting in poor curing or requiring a long time for the curing reaction. If the equivalence ratio is greater than 1.4, the curing agent that is not consumed during curing may become defective and degrade the mechanical properties.

The curing agent can be used in either monomer or oligomer form, and can be in powder or liquid form when mixed. These curing agents may be used alone or in combination of two or more. Moreover, you may use a hardening accelerator together.

Curing accelerators include amine compound curing accelerators typified by 1,8-diazabicyclo(5.4.0)undecene-7; imidazoles typified by 2-methylimidazole and 2-ethyl-4-methylimidazole. Compound-based curing accelerator: Phosphorus compound-based curing accelerator represented by triphenylphosphite, etc. can be used. Among them, the phosphorus compound-based curing accelerator is most preferable.

Various additives other than the epoxy resin and the block copolymer, such as flame retardants, fillers, colorants, release agents, and the like, may be added to the epoxy resin composition of the present invention, if necessary.

The filler is not particularly limited, but powders and fine particles of fused silica, crystalline silica, alumina, zircon, calcium silicate, calcium carbonate, silicon carbide, aluminum nitride, boron nitride, beryllia and zirconia are used. These fillers may be used alone or in combination of two or more. Among them, it is preferable to use fused silica because it lowers the coefficient of linear expansion. The shape of the filler is preferably spherical from the viewpoint of fluidity and abrasion resistance during molding.

The amount of the filler compounded is preferably 20 parts by mass to 2000 parts by mass, more preferably 50 to 2000 parts by mass, with respect to 100 parts by mass of the epoxy resin, from the viewpoint of lowering the moisture absorption rate, lowering the coefficient of linear expansion, and improving strength. parts, more preferably 100 to 2000 parts by mass, particularly preferably 100 to 1000 parts by mass, most preferably 200 to 800 parts by mass.

Examples of other additives include carbon black, calcium carbonate, titanium oxide, silica, aluminum hydroxide, glass fibers, hindered amine-based antidegradants, hindered phenol-based antidegradants, and the like.

These additives are preferably added before the epoxy resin composition is cured, and may be added in the form of powder, liquid, or slurry.

The epoxy resin composition of the present invention has good fluidity and excellent handleability. When used as a semiconductor encapsulating material, if the fluidity is poor, the epoxy resin composition cannot be filled into the details, which may cause voids and lead to damage to the package. When the block copolymer of the present invention is added to an epoxy resin, the increase in viscosity due to addition is small, and an epoxy resin composition having excellent fluidity can be obtained. Two or more block copolymers may be added to the epoxy resin composition.

The block copolymer of the present invention comprises a silicone skeleton that is incompatible with epoxy resin but has excellent flexibility, a polyalkylene glycol skeleton that is compatible with epoxy resin and has excellent flexibility, and an epoxy group that reacts with resin. Since it has connecting segments, it exhibits good dispersibility in the epoxy resin cured product, an effect of lowering the elastic modulus, and an effect of increasing toughness. A cured epoxy resin can be produced by a known method. For example, there is a method of mixing an epoxy resin, a curing agent, a curing accelerator, various additives, and a filler, and curing by heating.

The fluidity of the epoxy resin composition when producing a cured product is preferably low from the viewpoint of filling work efficiency when molding the encapsulant.

The fluidity of the epoxy resin composition can be evaluated by viscosity measurement with a rheometer. Specifically, an epoxy resin composition containing 17 parts by mass of a block copolymer and 270 parts by mass of a filler with respect to a total of 100 parts by mass of an epoxy resin, an epoxy resin curing agent, and a curing accelerator has a viscosity of 70. C. to 220.degree. C., and the viscosity at a temperature of 170.degree. C. is used as an index of fluidity. The viscosity value at a temperature of 170° C. is preferably 100 Pa·s or less, more preferably 80 Pa·s or less, and even more preferably 60 Pa·s or less. If the viscosity at a temperature of 170° C. is high, the fluidity of the epoxy resin composition is poor, and it is not possible to fill the details of the encapsulant during molding, causing cracks, which is not preferable.

The epoxy resin composition of the present invention can be prepared by adding the block copolymer to an epoxy resin and, if necessary, a curing agent, and kneading the mixture using a known kneader. Examples of kneaders include a three-roll kneader, a rotation-revolution mixer, and a planetary mixer.

The epoxy resin cured product of the present invention is obtained by subjecting the above epoxy resin composition to a curing reaction. In order to advance the curing reaction for obtaining the epoxy resin cured product, temperature may be applied as necessary. The temperature at that time is preferably room temperature to 250°C, more preferably 50 to 200°C, even more preferably 70 to 190°C, and particularly preferably 100 to 180°C. Also, if necessary, a temperature raising program may be applied. The rate of temperature increase at that time is not particularly limited, but is preferably 0.5 to 20°C/min, more preferably 0.5 to 10°C/min, and still more preferably 1 to 5°C/min. is.

The pressure during curing is preferably 1 to 100 kg/cm ² , more preferably 1 to 50 kg/cm ² , still more preferably 1 to 20 kg/cm ² , particularly preferably 1 to 5 kg/cm ² .

In the epoxy resin cured product of the present invention, the block copolymer is uniformly and finely dispersed inside. Whether or not the particles are homogeneously and finely dispersed can be judged by dyeing the cured resin plate with ruthenium tetroxide and checking the cross section of the resin plate with a transmission electron microscope. Staining with ruthenium tetroxide stains the polysiloxane domains. The finer the average domain diameter of the polysiloxane domain, the better the strain at break, and the better the effect of improving the toughness. The average domain diameter of the polysiloxane domain can be calculated by specifying the diameters of arbitrary 100 domains from the above transmission electron micrograph and calculating the arithmetic mean. If the domain is not spherical, the maximum diameter of the domain is taken as the diameter.

The average domain diameter of the polysiloxane domain determined by this method is preferably 20 µm or less, more preferably 5 µm or less, still more preferably 1 µm or less, and particularly preferably 500 µm or less. nm or less, highly preferably 200 nm or less, and most preferably 100 nm or less.

As described above, the epoxy group-containing block copolymer of the present invention can be well dispersed in the epoxy resin cured product, and the epoxy resin cured product can be made to have a low elastic modulus and high toughness. For these reasons, the block copolymer of the present invention is extremely useful as a stress reducing agent for epoxy resins.

EXAMPLES Next, the present invention will be described in more detail based on examples. The invention is not limited to these examples. The measurement methods used in the examples are as follows.

(1) Measurement of weight-average molecular weight The weight-average molecular weight of the block copolymer intermediate and the block copolymer obtained by reacting the block copolymer intermediate with the epoxy compound [C2'] was determined by the gel permeation chromatography method. was measured under the following conditions, and the molecular weight was calculated by comparing with a calibration curve using polymethyl methacrylate.
Apparatus: Shimadzu Corporation LC-20AD series Column: Showa Denko KF-806L × 2
Flow rate: 1.0 mL/min
Mobile phase: Tetrahydrofuran Detection: Differential refractometer Column temperature: 40°C.

(2) Determination of carboxyl group content According to JISK0070 (1992), 0.5 g of the block copolymer was dissolved in 10 g of tetrahydrofuran and titrated with 0.1 mol/L ethanolic potassium hydroxide using phenolphthalein as an indicator. Carboxyl group content was quantified.

(3) Quantification of Epoxy Group Content In accordance with JISK7236 (2009), 1.0 g of the block copolymer was dissolved in 30 mL of chloroform, 20 mL of acetic acid and 10 mL of tetraethylammonium bromide acetic acid solution were added, and crystal violet was used as an indicator to determine 0.00. Titration was performed with a 1 mol/L perchloric acid-acetic acid standard solution. A blank test was also conducted in the same manner to quantify the epoxy group content.

(4) Method for calculating content ⁽ silicone ratio) of structure derived from block [A] (silicone) H NMR measurement (500 MHz, 256 times of integration) was performed, and from the signal intensity of the structure derived from compound [A], compound [B] and binder [C1′] in the obtained spectrum, the entire block copolymer intermediate It was obtained by calculating the ratio of the mass of compound [A] to the mass of. The silicone ratio of the block copolymer obtained by reacting the block copolymer intermediate with the epoxy compound [C2′] was obtained by performing ¹ H NMR measurement of the block copolymer in the same manner as above. Calculate the ratio of the mass of the structure derived from the compound [A] to the mass of the entire block copolymer from the signal intensities of the structures derived from the compound [A], the compound [B], and the connecting segment [C] in the spectrum. I asked for it.

(5) Viscosity measurement The viscosity of the composition obtained by mixing the epoxy resin, epoxy resin curing agent, curing accelerator and block copolymer at the mixing ratio shown in each example was measured using a rheometer (MCR501 manufactured by Anton Paar). The viscosity was measured at 170°C under the following conditions.
Jig: φ25mm parallel plate Frequency: 0.5Hz
Strain: 100%
Gap: 1mm
Measurement temperature: 70°C to 220°C
Heating rate: 10°C/min Atmosphere: Nitrogen.

(6) Measurement of flexural modulus and strain at break A test piece was obtained by cutting the epoxy resin cured product in which the polysiloxane-polyalkylene glycol block copolymer was dispersed into a width of 10 mm, a length of 80 mm and a thickness of 4 mm. Using a Tensilon universal testing machine (TENSIRON TRG-1250, manufactured by A&D), according to JISK7171 (2008), a three-point bending test was performed under the conditions of a fulcrum distance of 64 mm and a test speed of 2 mm / min, and the bending elastic modulus was measured. and strain at break were measured. The measurement temperature was room temperature (23° C.), the number of measurements was n=5, and the average value was obtained.

<Synthesis of Block Copolymer Intermediate>
[Intermediate Synthesis Example 1]
In a 300 mL separable flask, 29 g of both terminal hydroxyl group-modified silicone oil (manufactured by Dow Corning Toray Co., Ltd., BY-16-201, weight average molecular weight 3100) as compound [A'], polypropylene as compound [B'] 61 g of glycol (manufactured by Sanyo Chemical Industries, Ltd., Newpol PP-2,000, diol type, weight average molecular weight 4,000), and pyromellitic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) as a linking agent [C1'] , molecular weight 218 g/mol) was added to perform nitrogen substitution. Thereafter, the mixture was heated to 160° C. and reacted for 8 hours to obtain a block copolymer intermediate. The resulting block copolymer intermediate had a silicone ratio of 30% by mass, a carboxyl group content of 0.80 mmol/g, a number average molecular weight of 7,400, and a weight average molecular weight of 15,000. Table 1 shows the results.

[Intermediate Synthesis Example 2]
15 g of both terminal hydroxyl group-modified silicone oil (manufactured by Dow Corning Toray Co., Ltd., BY-16-201, weight average molecular weight 3100) as compound [A'], both terminal amino group-modified polypropylene glycol (HUNTSMAN) as compound [B'] 75 g of Jeffamine D-2,000, diamine type, weight average molecular weight of 3700, manufactured by Tokyo Chemical Industry Co., Ltd., and pyromellitic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight of 218 g/mol) as a linking agent [C1′]. A block copolymer intermediate was obtained in the same manner as in Intermediate Synthesis Example 1, except that the weight was changed to 6 g. The resulting block copolymer intermediate had a silicone ratio of 15% by mass, a carboxyl group content of 0.88 mmol/g, a number average molecular weight of 18,000, and a weight average molecular weight of 38,300. Table 1 shows the results.

[Intermediate Synthesis Example 3]
In a 300 mL separable flask, 31 g of both terminal hydroxyl group-modified silicone oil (manufactured by Dow Corning Toray Co., Ltd., BY-16-201, weight average molecular weight 3100) as compound [A'], polypropylene as compound [B'] 59 g of glycol (Newpol PP-2,000, diol type, weight average molecular weight 4,000, manufactured by Sanyo Chemical Industries, Ltd.), and tetralin dianhydride (manufactured by New Japan Chemical Co., Ltd., After adding 11 g of a compound having a molecular weight of 300 g/mol) and replacing with nitrogen, the mixture was heated to 160° C., reacted for 8 hours, and then cooled to room temperature. After that, 4.0 g of 2-ethyl-2-oxazoline (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight: 218 g/mol) is added as a carboxyl group blocking agent, heated to 100° C. and reacted for 6 hours to form an intermediate block copolymer. got a body The resulting block copolymer intermediate had a silicone ratio of 30% by mass, a carboxyl group content of 0.43 mmol/g, a number average molecular weight of 10,400, and a weight average molecular weight of 21,000. Table 1 shows the results.

[Intermediate Synthesis Example 4]
As compound [A'], 40 g of both terminal hydroxyl group-modified silicone oil (manufactured by Shin-Etsu Chemical Co., Ltd., KF6000, weight average molecular weight 1600), as compound [B'] both terminal amino group-modified polypropylene glycol (manufactured by HUNTSMAN, Jeffamine D-400, diamine type, weight average molecular weight 430) was changed to 50 g, and tetralin dianhydride (manufactured by Shin Nippon Rika Co., Ltd., molecular weight 300 g / mol) was changed to 43 g as a linking agent [C1'] Intermediate synthesis example A block copolymer intermediate was obtained in the same manner as in 1. The resulting block copolymer intermediate had a silicone ratio of 30% by mass, a carboxyl group content of 2.15 mmol/g, a number average molecular weight of 3,900, and a weight average molecular weight of 6,000. Table 1 shows the results.

[Intermediate Synthesis Example 5]
71 g of hydroxyl-modified silicone oil (manufactured by Dow Corning Toray Co., Ltd., BY-16-201, weight average molecular weight 3100) as compound [A '], polypropylene glycol (manufactured by Sanyo Chemical Industries, Ltd.) as compound [B '] , Newpol PP-2,000, diol type, weight average molecular weight 4,000) 19 g, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene- as a linking agent [C1′] A block copolymer intermediate was obtained in the same manner as in Intermediate Synthesis Example 1, except that 1,2-dicarboxylic anhydride (manufactured by Shin Nippon Rika Co., Ltd., molecular weight: 264 g/mol) was changed to 10.8 g. The resulting block copolymer intermediate had a silicone ratio of 70% by mass, a carboxyl group content of 0.91 mmol/g, a number average molecular weight of 45,300, and a weight average molecular weight of 82,100. Table 1 shows the results.

<Synthesis of block copolymer>
[Synthesis Example 1]
In a 100 mL separable flask, 10 g of the block copolymer intermediate shown in Intermediate Synthesis Example 1 was added, and a bisphenol A type epoxy resin ("jER" (registered trademark) manufactured by Mitsubishi Chemical Corporation) was added as the compound [C2']. 828, epoxy equivalent weight 184-194) and 10 mg of tetraphenylphosphonium tetra-p-tolylborate (manufactured by Tokyo Chemical Industry Co., Ltd., molecular weight 659 g/mol) as a catalyst were added to perform nitrogen substitution. Then, the block copolymer was obtained by heating at 160 degreeC and making it react for 6 hours. The resulting block copolymer had a silicone ratio of 23% by mass, an epoxy group content of 0.59 mmol/g, a number average molecular weight of 12,700, and a weight average molecular weight of 54,400. Table 2 shows the results.

[Synthesis Example 2]
A reaction was carried out in the same manner as in Synthesis Example 1, except that the compound [C2′] was changed to 20.9 g of an ethylene glycol type epoxy resin (Denacol EX-810 manufactured by Nagase ChemteX Corporation, epoxy equivalent 113). 154 g of distilled water was added and the mixture was stirred at room temperature for 2 hours, and centrifuged (9,000 rpm, 10 minutes) to remove the supernatant in which the unreacted ethylene glycol type epoxy resin was dissolved. Then, the block copolymer was obtained by removing residual moisture by drying at 40° C. under vacuum for 12 hours. The resulting block copolymer intermediate had a silicone ratio of 26% by mass, an epoxy group content of 0.68 mmol/g, a number average molecular weight of 5,700, and a weight average molecular weight of 11,600. Table 2 shows the results.

[Synthesis Example 3]
In the same manner as in Synthesis Example 1, except that the compound [C2′] was changed to 15.4 g of a biphenyl-type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER” (registered trademark) YX4000H, epoxy equivalent 187 to 197). A polymer was obtained. The resulting block copolymer had a silicone ratio of 23% by mass, an epoxy group content of 0.58 mmol/g, a number average molecular weight of 11,400, and a weight average molecular weight of 36,600. Table 2 shows the results.

[Synthesis Example 4]
Except for changing the block copolymer intermediate to Intermediate Synthesis Example 2 and changing the compound [C2′] to 23.0 g of an ethylene glycol type epoxy resin (Denacol EX-810 manufactured by Nagase ChemteX Corporation, epoxy equivalent weight 113), A block copolymer was obtained in the same manner as in Synthesis Example 2. The resulting block copolymer intermediate had a silicone ratio of 13% by mass, an epoxy group content of 0.63 mmol/g, a number average molecular weight of 10,100, and a weight average molecular weight of 34,200. Table 2 shows the results.

[Synthesis Example 5]
The block copolymer intermediate is Intermediate Synthesis Example 3, and the compound [C2′] is 8.0 g of a bisphenol A type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER” (registered trademark) 828, epoxy equivalent weight 184 to 194). A block copolymer was obtained in the same manner as in Synthesis Example 1, except that it was changed to The obtained block copolymer had a silicone ratio of 25% by mass, an epoxy group content of 0.32 mmol/g, a number average molecular weight of 14,800, and a weight average molecular weight of 38,000. Table 2 shows the results.

[Synthesis Example 6]
Intermediate Synthesis Example 4 for the block copolymer intermediate, and 35.9 g of the compound [C2′] for the bisphenol F type epoxy resin (manufactured by Mitsubishi Chemical Corporation, “jER” (registered trademark) 806, epoxy equivalent weight 160 to 175). A block copolymer was obtained in the same manner as in Synthesis Example 1, except that it was changed to The resulting block copolymer had a silicone ratio of 20% by mass, an epoxy group content of 1.91 mmol/g, a number average molecular weight of 3,100, and a weight average molecular weight of 7,300. Table 2 shows the results.

[Synthesis Example 7]
Except that the block copolymer intermediate was changed to Intermediate Synthesis Example 5, and the compound [C2'] was changed to 50.1 g of a polyethylene glycol type epoxy resin (Denacol EX-861 manufactured by Nagase ChemteX Corporation, epoxy equivalent weight 551). A block copolymer was obtained in the same manner as in Synthesis Example 1. The resulting block copolymer had a silicone ratio of 63% by mass, an epoxy group content of 0.80 mmol/g, a number average molecular weight of 42,500, and a weight average molecular weight of 101,000. Table 2 shows the results.

[Reference example 1]
An attempt was made to prepare a block copolymer in the same manner as in Synthesis Example 1, except that the amount of bisphenol A type epoxy resin of compound [C2′] was changed to 5.9 g, but gelation occurred due to intermolecular cross-linking during the reaction. , a block copolymer was not obtained.

[Reference example 2]
An attempt was made to prepare a block copolymer in the same manner as in Synthesis Example 1, except that the catalyst tetraphenylphosphonium tetra-p-tolylborate was not used. No copolymer was obtained.

[Reference example 3]
A block copolymer was obtained in the same manner as in Synthesis Example 1, except that 81.4 g of the bisphenol A type epoxy resin of compound [C2'] was used. The resulting block copolymer had a silicone ratio of 23% by mass, an epoxy group content of 0.60 mmol/g, a number average molecular weight of 25,000, and a weight average molecular weight of 52,000. Table 2 shows the results.

<Preparation of epoxy resin cured product>
[Example 1]
Biphenyl type epoxy resin (manufactured by Mitsubishi Chemical Corporation, "jER" (registered trademark) YX4000H) 30.12 g as an epoxy resin, and 21.76 g of a phenol novolac type curing agent (manufactured by Meiwa Kasei Co., Ltd., H-1) as a curing agent was weighed into a 150 cc stainless steel beaker, melted in an oven at 120° C., and homogenized. After that, 17.16 g of the mixture of the block copolymer obtained in Synthesis Example 1 and bisphenol A type epoxy resin was added as an additive, and 0.3 g of tetraphenylphosphonium tetra-p-tolylborate was added as a curing accelerator. Using a mixer "Awatori Mixer" (manufactured by Thinky Co., Ltd.), mix once at 2000 rpm, 80 kPa, 1.5 minutes, stir once at 2000 rpm, 50 kPa, 1.5 minutes, 2000 rpm, 0.2 kPa , and stirred twice for 1.5 minutes to obtain an uncured epoxy resin composition.

This uncured epoxy resin composition was poured into an aluminum mold set with a 4 mm thick “Teflon” (registered trademark) spacer and a release film, and placed in an oven. The temperature of the oven was set to 80° C., held for 5 minutes, then heated to 175° C. at a rate of 1.5° C./min, and cured for 4 hours to obtain a cured epoxy resin having a thickness of 4 mm.

The obtained epoxy resin cured product was cut into pieces of 10 mm in width and 80 mm in length, and the flexural modulus and strain at break were measured by the above method. there were. The viscosity at 170°C was 2.6 Pa·s.

[Example 2]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Synthesis Example 2. The cured epoxy resin had a flexural modulus of 2.7 GPa and a strain at break of 14.6%. The viscosity at 170°C was 1.5 Pa·s.

[Example 3]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Synthesis Example 3. The cured epoxy resin had a flexural modulus of 2.6 GPa and a strain at break of 13.4%. The viscosity at 170°C was 2.7 Pa·s.

[Example 4]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Synthesis Example 4. The cured epoxy resin had a flexural modulus of 2.9 GPa and a strain at break of 14.1%. The viscosity at 170°C was 2.3 Pa·s.

[Example 5]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Synthesis Example 5. The cured epoxy resin had a flexural modulus of 2.8 GPa and a strain at break of 12.3%. The viscosity at 170°C was 1.2 Pa·s.

[Example 6]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Synthesis Example 6. The cured epoxy resin had a flexural modulus of 2.6 GPa and a strain at break of 15.2%. The viscosity at 170°C was 2.5 Pa·s.

[Example 7]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Synthesis Example 7. The cured epoxy resin had a flexural modulus of 1.9 GPa and a strain at break of 10.3%. The viscosity at 170°C was 2.9 Pa·s.

[Comparative Example 1]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was not used. The cured epoxy resin had a flexural modulus of 3.1 GPa and a strain at break of 8.7%.

[Comparative Example 2]
An epoxy resin cured product was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to both terminal epoxy group-modified silicone oil (manufactured by Momentive Performance Materials Co., Ltd., TSF4730). rice field. The cured epoxy resin had a flexural modulus of 2.4 GPa and a strain at break of 9.3%.

[Comparative Example 3]
A cured epoxy resin was obtained in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to polypropylene glycol (manufactured by Sanyo Kasei Co., Ltd., Newpol PP4000). The cured epoxy resin had a flexural modulus of 3.4 GPa and a strain at break of 8.3%.

[Comparative Example 4]
An attempt was made to prepare an epoxy resin cured product in the same manner as in Example 1, except that the block copolymer obtained in Synthesis Example 1 was changed to the block copolymer obtained in Reference Example 3. Since the ratio of the A-type epoxy resin was large, it was not possible to prepare a resin cured product to which the block copolymer was added at the desired ratio.

Claims (10)

A block copolymer comprising block [A], block [B], and connecting segment [C], wherein block [A] has a structural unit represented by general formula (1),

(R ₁ represents hydrogen, an alkyl group having 1 to 10 carbon atoms, or a phenyl group, which may be the same or different. n represents a repeating unit of 5 to 70.)
Block [B] has a structural unit represented by general formula (2),

(R ₂ represents an alkylene group or an arylene group having 2 to 10 carbon atoms, which may be the same or different. m represents a repeating unit of 3 to 100.)
The connecting segment [C] has an epoxy group and contains an ester bond and/or an amide bond, the epoxy group content of the block copolymer is 0.1 to 3.0 mmol/g, and the weight average molecular weight is A block copolymer of 5,000 to 500,000. 2. The block copolymer according to claim 1, wherein the connecting segment [C] is represented by general formulas (3) and/or (4).

(X represents -O- or -NH-, which may be the same or different. Y represents an organic group having 4 to 14 carbon atoms, which may be the same or different. Z contains an epoxy group. each represents an organic group, which may be the same or different, and R ₃ represents an organic group having 1 to 7 carbon atoms, may contain an amide group, and may be the same or different.) 3. The block copolymer according to claim 1, wherein Y in general formulas (3) and (4) is represented by any one of general formulas (5) to (13).

4. The block copolymer according to any one of claims 1 to 3, wherein Z in said general formulas (3) and (4) is represented by general formula (14) or (15).

(R ₄ represents an alkylene group having 2 to 10 carbon atoms, l represents a repeating unit of 1 to 40.)

(R ₅ represents hydrogen or a methyl group, and k represents a repeating unit of 0 to 10.) 5. The block copolymer according to any one of claims 1 to 4, wherein the content of the structure derived from block [A] is 10% by mass or more and 90% by mass or less. A compound [A'] having a structural unit represented by the general formula (1) and having at both ends any functional group selected from a hydroxyl group and an amino group, and a compound represented by the general formula (2) and a compound [B′] having at both ends a functional group selected from a hydroxyl group and an amino group, and a linking agent [C1 '] to obtain a block copolymer intermediate, and a compound [C2'] having two or more epoxy groups in the molecule at 5 to 50 times the moles of [C1'] in the presence of a catalyst. The method for producing a block copolymer according to any one of claims 1 to 5, wherein the reaction is performed. The method for producing a block copolymer according to claim 6, wherein after reacting the compound [C2'], unreacted [C2'] is removed with a solvent of 1 to 10 times the weight of the reaction product. 8. The method for producing a block copolymer according to claim 6 or 7, wherein the compound [C2'] having two or more epoxy groups in the molecule is represented by general formula (16) or (17).

(R ₄ represents an alkylene group having 2 to 10 carbon atoms, l represents a repeating unit of 1 to 40.)

(R ₅ represents hydrogen or a methyl group, k represents a repeating unit of 0 to 10.) An epoxy resin composition comprising the block copolymer according to any one of claims 1 to 5 and an epoxy resin. A cured epoxy resin obtained by curing the epoxy resin composition of claim 9 .