TWI599611B - Liquid epoxy resin composition - Google Patents

Description

Liquid epoxy resin composition

This invention relates to liquid epoxy resin compositions. More specifically, the present invention relates to a low-viscosity liquid epoxy resin composition containing a glycidyl ether compound and a phenolic curing agent.

Epoxy resin is widely used in electronic components such as semiconductor sealing materials, printed circuit boards, build-up substrates, and resist inks because of its excellent electrical properties such as electrical insulation, heat resistance, moisture resistance, and dimensional stability. Conductive adhesives such as conductive pastes, other adhesives, liquid sealing materials such as underfill, liquid crystal sealing materials, cover films for flexible substrates, adhesive films for buildup, substrates for composite materials, paints, and light Resistive materials, chromogenic materials, etc. In the field of electronic materials such as semiconductors and printed wiring boards, there is an increasing demand for high performance of sealing materials and substrate materials in connection with technological innovations in these fields.

For example, the resin used for the liquid sealing material such as the underfill material is reduced in size due to the miniaturization of the machine and the increase in the filling property of the fine parts. Further, in a semiconductor sealing material, a conductive adhesive or the like, heat resistance due to an increase in the amount of filler ‧ dimensional stability For the purpose of improvement or low resistance due to high filling of the conductive filler, the resin composition has a high requirement for low viscosity. In these applications, high heat resistance is also an essential condition, so the resin needs to have both heat resistance and low viscosity.

For the low viscosity of the resin composition, a method of adding a low molecular weight epoxy compound as a reactive diluent is generally used. However, in the method of adding a monofunctional or difunctional epoxy compound, the crosslinking density of the resin is lowered, and the heat resistance of the cured product is largely lowered. On the other hand, a trifunctional or higher epoxy compound is easily polymerized by a ring-opening addition product formed by a reaction between a polyol which is a raw material during synthesis and epichlorohydrin, and thus it is known that a molecular weight distribution is wide and the number of functional groups is large. Many but the glass transition temperature of the hardened material is significantly reduced.

On the other hand, as the curing agent for the epoxy resin, various compounds such as an amine compound, a phenol resin, an acid anhydride, an imidazole compound, and a thiol compound can be used, but in the case of low viscosity, an acid anhydride, an amine compound, or an imidazole compound is generally used. As a hardener. Although the phenol resin hardener has a characteristic of reflecting a hard resin skeleton and imparting a cured material having a high glass transition point, most of them are solid at room temperature, and therefore are used in a solvent-free conductive adhesive and a primer. The example is limited.

In recent years, there has been a report of a liquid phenol resin at room temperature by introducing a substituent such as an allyl group into an aromatic ring of a phenol resin (for example, Patent Documents 1 and 2). However, when a liquid phenol resin is used as a curing agent, a resin having a high degree of freedom (providing molecular flexibility) in the resin generally has a glass transition temperature of a cured product even though it contains a hard resin skeleton imparting high heat resistance. low. Therefore, it is used as a semi-conductor for high temperature conditions. In the case of a body sealant, a underfill material, and a conductive adhesive, it is considered that the reliability is poor. Patent Document 3 discloses that by epoxidizing a carbon-carbon double bond of a compound having three or more carbon-carbon double bonds in the molecule by an oxidation reaction using hydrogen peroxide as an oxidizing agent, it is possible to suppress the accompanying side reaction. The molecular weight distribution due to the formation of the high molecular weight is increased, and a liquid epoxy resin composition having a low total chlorine content can be obtained. However, it is not described or suggested that a liquid curable composition excellent in heat resistance can be obtained by using a phenol resin having a solid temperature at room temperature as a curing agent.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] JP-A-10-168283

[Patent Document 2] JP-A-2000-169537

[Patent Document 3] JP-A-2013-189504

In view of the above problems, the present invention has been made in an effort to provide a low-viscosity liquid epoxy resin composition which can obtain a cured product having excellent heat resistance.

From the previous review by the Applicant, it was found that by using an oxidation reaction using hydrogen peroxide as an oxidizing agent, the carbon-carbon double bond of a compound having a carbon-carbon double bond in the molecule is epoxidized to suppress the conventional polyol and epichlorohydrin. The molecular weight distribution due to the formation of a polymer having a side reaction is broadened as in the case of an alcohol reactant, and a high-purity liquid epoxy compound having a very low total chlorine content can be obtained. The epoxy compound thus obtained is characterized in that it has a low viscosity at room temperature and imparts a cured product having a high glass transition temperature as compared with the conventional product.

The inventors of the present invention conducted a review of the above-mentioned problems, and found a low-viscosity glycidyl group obtained by epoxidizing a carbon-carbon double bond of a compound having a carbon-carbon double bond in the molecule in order to solve the above problems. The ether compound dissolves the solid phenol resin as a hardener, and not only a liquid epoxy resin composition which has low heat resistance at room temperature and excellent heat resistance from a glycidyl ether and a solid phenol resin hardener can be obtained. The present invention has been completed.

That is, the present invention encompasses the following embodiments.

[1] A liquid epoxy resin composition comprising a liquid epoxy resin composition comprising (A) a glycidyl ether compound and (B) a phenol resin-based curing agent, characterized by (A) glycidol The ether compound is liquid at 25 ° C and substantially does not contain a carbon-chloride bond, and the above (B) phenol resin-based hardener is a solid at 25 ° C.

[2] The liquid epoxy resin composition according to [1], which does not contain a solvent and a reactive diluent.

[3] The liquid epoxy resin composition according to any one of [1], wherein (C) a curing accelerator is further contained.

[4] The liquid epoxy resin composition according to any one of [1] to [3] wherein the (A) glycidyl ether compound is a polycondensed water of an aliphatic polyol having 3 to 30 carbon atoms. Glyceryl ether.

[5] The liquid epoxy resin composition according to any one of [1] to [4] wherein the (A) glycidyl ether compound is an allyl carbon-carbon of an allyl ether compound. A double bond is obtained by reacting with an oxidizing agent.

[6] The liquid epoxy resin composition according to any one of [1] to [5] wherein the (A) glycidyl ether compound has a viscosity at 25 ° C of 1 mPa ‧ to 1000 mPa ‧ s.

[7] The liquid epoxy resin composition according to any one of [1], wherein the (A) glycidyl ether compound comprises a condensed water selected from 1,4-cyclohexanedimethanol. Glyceryl ether, trimethylolpropane triglycidyl ether, glycerol triglycidyl ether, pentaerythritol tetraglycidyl ether, ditrimethylolpropane tetraglycidyl ether, diglycerin tetraglycidyl ether, two At least one of the group consisting of pentaerythritol hexa glycidyl ether and sorbitol hexa glycidyl ether.

The liquid epoxy resin composition according to any one of the above aspects, wherein the (B) phenol resin-based curing agent is selected from the group consisting of a phenol novolak resin and a cresol novolak resin. At least one of the group consisting of a triphenylmethane type phenol resin and a dicyclopentadiene-modified phenol resin.

The liquid epoxy resin composition according to any one of the above-mentioned (A) glycidyl ether compounds, which contains the above-mentioned (B) phenol resin-based hardening. The agent is 20 to 300 parts by mass.

[10] The liquid epoxy resin composition according to any one of [3], wherein the (C) hardening accelerator is selected from the group consisting of an imidazole compound and a derivative thereof, a phosphine compound, and a derivative thereof. And at least one of the group consisting of a tertiary amine and a derivative thereof.

[11] The liquid epoxy resin composition according to any one of [3] to [10], wherein the total mass of the (A) glycidyl ether compound and (B) phenol resin-based hardener is 100. The fraction (C) hardening accelerator is contained in an amount of 0.1 to 10 parts by mass.

The liquid epoxy resin composition of the present invention contains a solid (B) phenol resin-based curing agent, and the cured product can have a high glass transition temperature (Tg). The liquid (A) glycidyl ether compound which does not contain a high molecular weight component has a low viscosity and is excellent in compatibility with a solid (B) phenol resin-based hardener, and can be used without using a solvent and/or a reactive diluent. A low viscosity liquid epoxy resin composition is prepared. As a result, even when the filler is highly filled, a cured product having excellent fluidity and high glass transition temperature can be obtained. Therefore, the liquid epoxy resin composition of the present invention is particularly preferably used for liquid sealing materials such as semiconductor sealing materials and underfill materials. Use of sealing materials and use of conductive adhesives.

Fig. 1 is a gas chromatographic/mass analysis (GC/MS) of 1,4-cyclohexanedimethanol diglycidyl ether (CDMDG) obtained in Production Example 2 used in the examples. A plot of the mass spectrum in peak 1 in the ion chromatogram and chromatogram.

2] Fig. 2 is a glycerol triad obtained in Production Example 3 used in the examples. A chromatogram of mass spectrometry/mass spectrometry (GC/MS) of hydroglyceryl ether (GLYG) and a mass spectrum of peak 1 in the chromatogram.

3 is a full ion chromatogram and chromatography obtained by size exclusion chromatography/mass analysis (SEC/MS) of pentaerythritol tetraglycidyl ether (PETG) obtained in Production Example 4 used in the examples. In the figure, the division is 1~4 (division 1: residence time 11~12 minutes, division 2: residence time 12~13 minutes, division 3: residence time 13~14 minutes, division 4: residence time 14~15 minutes) A map of the mass spectrum.

4 is a total ion chromatography obtained by size exclusion chromatography/mass analysis (SEC/MS) of commercially available pentaerythritol polyglycidyl ether (Denacol (registered trademark) EX-411) used in Comparative Example 2. The division and the chromatogram are divided into 1~4 (division 1: residence time 11~12 minutes, division 2: residence time 12~13 minutes, division 3: residence time 13~14 minutes, division 4: residence time 14~15) A plot of the mass spectrum in minutes).

Fig. 5 is a graph showing the molecular weight distribution of the phenol resin-based curing agents (B-1) to (B-4) used in the examples.

[Best Practice for Carrying Out the Invention]

The invention will be described in detail below.

The liquid epoxy resin composition of the present invention contains (A) a glycidyl ether compound and (B) a phenol resin-based hardener, characterized in that the (A) glycidyl ether compound is liquid at 25 ° C and substantially contains no carbon. - chlorine bond, and (B) The phenol resin-based hardener was a solid at 25 °C.

(A) glycidyl ether compound

The glycidyl ether compound contained in the liquid epoxy resin composition of the present invention is a compound which is liquid in nature at 25 ° C which does not contain a carbon-chloride bond in its molecule. The glycidyl ether compound used in the conventional epoxy resin composition is mainly produced by a condensation reaction of an aliphatic alcohol or a phenol with epichlorohydrin, but at that time, the molecule has a carbon represented by the formula (1). A compound of a terminal group of a chlorine bond is produced as a by-product. It takes a lot of time or time to separate and remove such by-products, and it is extremely difficult to completely remove them. When the glycidyl ether compound in which the by-product is mixed is used, the obtained cured product has a low glass transition temperature and poor heat resistance, in addition to the viscosity of the resin composition.

In the present invention, "substantially free of carbon-chlorine bond" means that a peak of a compound containing a carbon-chlorine bond and a fragment thereof cannot be confirmed in a mass spectrum of a glycidyl ether compound. More specifically, in the mass spectrum of the glycidyl ether compound, it is not possible to confirm a carbon-chlorine-containing compound which is produced by the epichlorohydrin compound when the glycidyl ether compound is produced by the epichlorohydrin method using an aliphatic alcohol as a raw material. The peak corresponding to the fragment.

The method for producing a glycidyl ether compound which does not form the above-mentioned by-products used in the present invention may, for example, be an allyl ether compound. The allylic carbon-carbon double bond of the olefin is oxidized by an oxidizing agent, and more specifically, it can be produced, for example, by the following method.

1) A method in which a carbon-carbon double bond of an allyl ether compound is oxidized using a peracid (peracetic acid or the like) as an oxidizing agent (for example, JP-A-7-145221, etc.)

2) A method of oxidizing a carbon-carbon double bond of an allyl ether compound using hydrogen peroxide (more specifically, an aqueous hydrogen peroxide solution) as an oxidizing agent and using a catalyst such as tungsten or zeolite (for example, JP-A-60- Bulletin No. 60123, etc.)

3) a method of oxidizing a carbon-carbon double bond of an allyl ether compound using hydrogen peroxide (more specifically, an aqueous hydrogen peroxide solution) as an oxidizing agent in an alkaline environment in the presence of acetonitrile (for example, JP-A-59-227872) Bulletin, etc.)

The glycidyl ether compound obtained by the above method is preferably used after being purified by distillation or adsorbent treatment, if necessary.

The glycidyl ether compound used in the present invention is a liquid at 25 °C. The viscosity of the glycidyl ether compound at 25 ° C is 1 mPa. s~1000mPa. The range of s is good. In several suitable implementations, the viscosity of the glycidyl ether compound at 25 ° C is 5 mPa. Above s, or 10mPa. Above s, 500mPa. s below, or 300mPa. s below. The epoxy equivalent of the glycidyl ether compound is preferably in the range of 80 to 300 g/eq, more preferably in the range of 90 to 200 g/eq. When the epoxy equivalent is less than 80 g/eq, the impact resistance of the cured product is reduced. On the other hand, when it exceeds 300 g/eq, the viscosity at the time of adding a hardener becomes very high, and it is operability. Getting worse.

The glycidyl ether compound used in the present invention preferably has an average of two or more glycidyl groups per molecule in exhibiting good mechanical strength as a cured product. Wherein a polyallyl ether of an aliphatic polyol having 3 to 30 carbon atoms is used (at least two of the hydroxyl groups of the polyol are substituted with an allyloxy group, and a part of the hydroxyl group remains The polyglycidyl ether of the aliphatic polyhydric alcohol having 3 to 30 carbon atoms obtained by epoxidizing the carbon-carbon double bond with an oxidizing agent is particularly preferable.

Specific examples thereof include 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,8-octanediol diglycidyl ether, and 1,9-fluorene. Alkylene glycol diglycidyl ether, 1,10-decanediol diglycidyl ether, diethylene glycol diglycidyl ether, triethylene glycol diglycidyl ether, dipropylene glycol diglycidyl ether , tripropylene glycol diglycidyl ether, 1,4-cyclohexane dimethanol diglycidyl ether, tricyclodecane dimethanol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, trimethylol Propane triglycidyl ether, glycerol triglycidyl ether, pentaerythritol tetraglycidyl ether, ditrimethylolpropane tetraglycidyl ether, diglycerin tetraglycidyl ether, erythritol tetraglycidyl ether, Xylitol pentahydroglycidyl ether, dipentaerythritol pentaglycidyl ether, dipentaerythritol hexa glycidyl ether, sorbitol hexa glycidyl ether, inositol pental glycidyl ether, inositol hexa glycidyl ether, etc. . In this case, in view of the viscosity of the compound and the heat resistance of the cured product, 1,4-cyclohexanedimethanol diglycidyl ether, trimethylolpropane triglycidyl ether, glycerol triglycidyl ether Pentaerythritol tetraglycidyl ether, ditrimethylol Alkane tetraglycidyl ether, diglycerin tetraglycidyl ether, dipentaerythritol hexa glycidyl ether, and sorbitol hexa glycidyl ether are preferred, 1,4-cyclohexane dimethanol diglycidyl ether, Tricyclodecane dimethanol diglycidyl ether, trimethylolpropane triglycidyl ether, glycerol triglycidyl ether, and pentaerythritol tetraglycidyl ether are particularly preferred.

(B) phenol resin-based hardener

The liquid epoxy resin composition of the present invention contains (B) a phenol resin-based curing agent which is reacted with the above-mentioned (A) glycidyl ether compound to form a cured product. The (B) phenol resin-based hardener used in the present invention is a solid at 25 °C. In comparison with the case of using a liquid phenolic curing agent, the rigidity of the resin is high, and the molecular free rotation is restrained, and a cured product having a high glass transition temperature can be obtained.

As the phenol resin-based curing agent, a compound having two or more phenolic hydroxyl groups in one molecule is used. Specific examples thereof include bisphenol A, bisphenol F, phenol novolac resin, cresol novolak resin, triphenylmethane type phenol resin, dicyclopentadiene modified phenol resin, phenol aralkyl resin, and race. Drop-off phenol resin, terpene phenol resin, and the like. Among these, the phenol novolac resin, the cresol novolac resin, the triphenylmethane type phenol resin, and the dicyclopentadiene-modified phenol resin are particularly compatible with the glycidyl ether or heat resistance. good. These may be used alone or in combination of two or more. These phenol resin-based curing agents are excellent in compatibility with the glycidyl ether compound, and can be uniformly dissolved without using a solvent and/or a reactive diluent to obtain a liquid curable composition.

The amount of the phenol resin-based curing agent in the liquid epoxy resin composition of the present invention varies depending on the hydroxyl equivalent of the phenol resin-based curing agent and the epoxy equivalent of the glycidyl ether compound to be used, but is relatively reduced. The phenol resin-based curing agent is blended in an amount of 20 to 300 parts by mass based on 100 parts by mass of the glyceryl ether compound, and is preferably a viscosity of the resin composition or heat resistance of the cured product. The amount of the phenol resin-based curing agent is preferably from 40 to 200 parts by mass, more preferably from 50 to 150 parts by mass, per 100 parts by mass of the glycidyl ether compound.

(C) hardening accelerator

In the liquid epoxy resin composition of the present invention, in order to obtain appropriate curability, a curing accelerator may be used as necessary. The hardening accelerator is not particularly limited as long as it can be used as a curing accelerator for an epoxy resin. However, it is preferred to use an imidazole-based, phosphine-based or tertiary amine-based curing accelerator.

Specific examples of the imidazole-based hardening accelerator include imidazole compounds and derivatives thereof, such as 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 2-phenyl-4-. Methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, epoxy-imidazole adduct, and the like. The phosphine-based hardening accelerator may, for example, be a phosphine compound and a derivative thereof, for example, triphenylphosphine, tri-p-tolylphosphine, tricyclohexylphosphine, 1,4-bisdiphenylphosphinobutane, tetraphenyl. Tetraphenyl borate, triphenylphosphine triphenylborane, tetraphenylphosphonium tetra-p-tolyl borate, and the like. As a tertiary amine hardening accelerator, it is a tertiary amine and its derivatives, such as 1,8-diaza Heterobicyclo[5,4,0]undecene-7 (DBU), 1,5-diazabicyclo[4,3,0]nonene-5 (DBN), phenolate of DBU, octyl group of DBU Acid salt, p-toluenesulfonate of DBU, phenol novolak resin salt of DBU, phenol novolak resin salt of DBN (diazabicyclononene), tetraphenylborate of DBU derivative, triethylenediamine , benzyldimethylamine, triethanolamine, and the like.

The amount of the curing accelerator to be used varies depending on the type of the phenol resin-based curing agent and the curing accelerator, and is 0.1 to 10 parts by mass based on 100 parts by mass of the total amount of the glycidyl ether compound and the phenol resin-based curing agent. Proportional use is preferred.

Further, the liquid epoxy resin composition of the present invention may contain a filler (for example, ceria, alumina, boron nitride, aluminum nitride, etc.), if necessary, without impairing the effect of the present invention. A colorant (for example, carbon black, dye, etc.), a flame retardant, an ion scavenger, an antifoaming agent, a flat agent, and the like. Further, in order to improve the adhesion of the substrate, a decane coupling agent may be contained. Specific examples of the decane coupling agent include 3-glycidoxypropyltrimethoxydecane, 3-glycidoxypropyl (meth)dimethoxydecane, and 2-(2,3). -Epoxycyclohexyl)ethyltrimethoxydecane, 3-methylpropenyloxypropyltrimethoxydecane, 3-aminopropyltriethoxydecane, 3-(2-aminoethyl) Aminopropyltrimethoxydecane, and the like.

The preparation method of the liquid epoxy resin composition of the present invention is not particularly limited, and the components can be put into a crushing machine, a ball mill, a three-roll mill, a rotary mixer, a two-axis mixer, etc. at a specific mixing ratio. The mixer is mixed and modulated.

The viscosity of the liquid epoxy resin composition of the present invention is not particularly limited, and various types of viscosity can be used depending on the type of the glycidyl ether compound and the phenol resin-based curing agent, and the viscosity of the resin composition is determined by the workability point. 2000Pa. The following is better. When the resin composition contains a filler, the filler filling amount is increased and the precipitation point is prevented, and the viscosity of the resin composition before the filler filling is 0.1 Pa. s~1000Pa. The range of s is good. When the viscosity is too low, the filler tends to precipitate and the dispersion state becomes uneven. When the viscosity is too high, it is difficult to increase the filler filling amount. The viscosity of the resin composition before filling the filler is more preferably 1 Pa. s~500Pa. The range of s is better than 5Pa. s~250Pa. The range of s.

[Examples]

The present invention will be described in more detail below by way of examples and comparative examples, but the invention is not limited thereto.

<Measurement of epoxy equivalent>

The epoxy equivalent is determined in accordance with JIS-K7236. The sample was weighed 0.1 to 0.2 g, placed in a conical flask, and then dissolved in 10 mL of dichloromethane. Next, 20 mL of acetic acid was added, and 10 mL of a tetraethylammonium bromide acetic acid solution (100 g of tetraethylammonium bromide dissolved in 400 mL of acetic acid) was added. To the solution, 1, 2 drops of crystal violet indicator were added, and titration was carried out with a 0.1 mol/L perchloric acid acetic acid solution, and the epoxy equivalent was determined by the following formula based on the titration result.

Epoxy equivalent (g/eq) = (1000 × m) / {(V1-V0) × c}

m: the mass of the sample (g)

V0: the amount of perchloric acid acetic acid solution (mL) consumed by titration until the end point in the empty test

V1: The amount of perchloric acid acetic acid solution (mL) consumed by titration until the end point

c: concentration of perchloric acid acetic acid solution (0.1 mol/L)

<Measurement of viscosity>

The viscosity of the glycidyl ether compound and the liquid epoxy resin composition was measured using a cone and plate type viscometer RVDV-II+Pro manufactured by a viscometer. 0.5 mL of the sample was placed on the sample stage, and the mixture was held by a cone plate (diameter: 48 mm or 24 mm, taper angle: 3°), and the viscosity was measured under the conditions of a temperature of 25 ° C and a number of rotations of 1 rpm. Viscosity 1mPa. s~1Pa. For the sample of s, use a cone plate with a diameter of 48 mm, 1 Pa. s~2000Pa. The sample of s uses a cone plate with a diameter of 24 mm.

<Measurement of total chlorine amount>

The measurement of the total chlorine amount is carried out by mass spectrometry by causing the sample to be decomposed and decomposed at a high temperature of 800 ° C or higher to cause the decomposition gas to be absorbed by ultrapure water or the like. The ion chromatography was carried out by a column of 861 Advanced Compact IC and Shodex SI-90 4E manufactured by Metrohm Co., Ltd., and a 1.7 mM NaHCO ₃ /1.8 mM Na ₂ CO ₃ aqueous solution was used as a solution, and the flow rate was measured at a flow rate of 1.3 mL/min.

<Measurement of mass spectrometry> <GC/MS measurement>

Gas chromatography/mass analysis (GC/MS) of the chemical ionization (CI) method was carried out under the following conditions.

Device: 7890A (GC part, Agilent Technologies Co., Ltd.) / JEOL JMS-Q1000GC MkII (MS part, manufactured by Nippon Electronics Co., Ltd.)

Column: Agilent HP-5 (inner diameter 0.32mm; length 30m; film thickness 0.25μm)

Column heater temperature: 50 ° C (3 min) → [20 ° C / min] → 320 ° C (10 min)

Carrier gas: He

Column flow: 1.5mL/min (fixed flow rate mode)

Injection mode: split (1:20)

Injection temperature: 300 ° C

Injection volume: 1 μL (using an auto-injector)

Transmission line temperature: 300 ° C

Ionization method: CI (chemical ionization method)

CI reaction gas: isobutane

Scanning range: m/z 60~600

Sample preparation: 50 mg/mL (solvent is acetone)

<SEC/MS measurement>

Size exclusion chromatography/mass analysis (SEC/MS) of the atmospheric pressure chemical ionization (APCI) method was carried out under the following conditions.

1) SEC (size exclusion chromatography)

Column: ShodexGPC KF-402×2

Column temperature: 40 ° C

Dissolved solution: tetrahydrofuran (HPLC grade), 0.3 mL/min

2) MS (Quality Analysis) Department

Ionization method: atmospheric pressure chemical ionization (+)

Scanning range: m/z50~2000

[Production Example 1: Synthesis of Polyolyl Ether]

The various polyallyl ethers used in Production Examples 2 to 4 to be described later were synthesized by Williamson synthesis. As an example, the synthesis of 1,4-cyclohexanedimethanol diallyl ether is as follows.

In a 2 liter three-necked flask equipped with a stirrer and a thermometer, 144.2 g (1.00 mol) of 1,4-cyclohexanedimethanol (manufactured by Nippon Chemical Co., Ltd.) was added to carry out nitrogen substitution in the reaction apparatus, and hydrogen peroxide was added thereto. 480.0 g (6.0 mol) of a sodium aqueous solution (50 mass%) was heated to 40 ° C, and 3.224 g (0.01 mol) of tetrabutylammonium bromide (manufactured by Wako Pure Chemical Industries, Ltd.) was added. While maintaining the inside of the reaction system at about 40 ° C, 168.3 g (2.20 mol) of allyl chloride (manufactured by Kashima Chemical Co., Ltd.) was dropped, and after 2 hours, 72.11 g of 1,4-cyclohexanedimethanol was added ( 0.50 mol), allyl chloride, 84.17 g (1.10 mol). Thereafter, the reaction was continued while the reaction temperature was gradually increased, and 25.25 g (0.33 mol) of allyl chloride was gradually added to see the progress of the reaction, and the reaction was completed. After the reaction was completed, 33.7 g of toluene was added for liquid separation treatment to make organic The layer was washed with pure water at 200 mL/time until neutral. After liquid separation, the organic layer was distilled off with a solvent, an allyl chloride or the like by an evaporator. After the solvent was distilled off, 1,4-cyclohexanedimethanol diallyl ether was obtained by precise distillation (distillation temperature: 63.9 to 67.7 ° C (11 Pa)).

Other polyallyl ethers were also synthesized according to the above procedure.

[Production Example 2: Synthesis of 1,4-cyclohexanedimethanol diglycidyl ether (CDMDG)]

1,4-cyclohexanedimethanol diallyl ether (100 g, 0.45 mol) obtained in the above Production Example 1, acetonitrile (73.2 g, 1.78 mol, manufactured by Pure Chemical Co., Ltd.), and methanol (92.9 g, 2.90) Mol, manufactured by Pure Chemical Co., Ltd.) was weighed into a 500 mL 3-way eggplant type flask. Using a water bath, the internal temperature was 35 ° C, and the pH was brought to 10.5 with a saturated aqueous potassium hydroxide solution (KOH/H ₂ O = 110 g / 100 mL). When the reaction is completed, the reaction temperature is not more than 40 ° C, and a saturated aqueous solution of potassium hydroxide is added at any time, and the pH is controlled to be in the range of 10.75 to 10.25. A 45% aqueous hydrogen peroxide solution (81.6 g, 1.08 mol, manufactured by Nippon Peroxide Co., Ltd.) was dropped in a 300 mL dropping funnel for 16 hours, and further stirred for 10 hours to complete the reaction. The reaction liquid was determined by gas chromatography to confirm that the conversion ratio of the cyclohexane dimethanol diallyl ether of the substrate was 100%, and the yield of the cyclohexane dimethanol diglycidyl ether of the diepoxide was 88.5. %, the yield of monomonoglycid monoglycidyl ether was 2.6%.

The obtained reaction solution was subjected to a precision distillation apparatus manufactured by Dako Industrial Co., Ltd. at a vacuum of 13 kPa and a flask temperature of 265 ° C. Distillation was carried out at a column temperature of 190 ° C to obtain 1,4-cyclohexanedimethanol diglycidyl ether (CDMDG) having a purity of 99.5% by gas chromatography. The viscosity of CDMDG is 34mPa. s, the epoxy equivalent obtained by titration was 136. The total chlorine content was 5 ppm, and it was confirmed by GC/MS analysis (Fig. 1) that no organic chlorine was contained (the chlorine was not derived from a compound having a carbon-chlorine bond).

[Production Example 3: Synthesis of glycerol triglycidyl ether (GLYG)]

Triglyceride (50 g, 0.24 mol) obtained in the same manner as in Production Example 1 above, acetonitrile (77 g, 1.9 mol, manufactured by Pure Chemical Co., Ltd.), methanol (91 g, 2.8 mol, Pure Chemical Co., Ltd.) The solution was placed in a 500 mL 4-neck flask, and a small amount of a 50% by mass aqueous potassium hydroxide solution was added to adjust the pH of the reaction solution to about 10.5. When the reaction is completed and the reaction temperature does not exceed 40 ° C, a saturated aqueous solution of potassium hydroxide is added at any time to control the pH in the range of 10.75 to 10.25. A 35 mass% aqueous hydrogen peroxide solution (82 g, 0.8 mol, manufactured by Nippon Peroxide Co., Ltd.) was dropped for 9 hours, and after further stirring for 16 hours, 1 g of sodium sulfite was added to the reaction liquid to stop the reaction. After the solvent was distilled off using a diaphragm pump, 500 g of ethyl acetate and 300 g of a 10% by mass aqueous sodium sulfate solution were added, and the aqueous layer and the organic layer were separated. Thereafter, the organic layer was washed five times with 20 g of pure water, and impurities such as sodium sulfite and by-product acetaminophen were removed, and then the solvent was distilled off to obtain a purity of 91%, a yield of 36 g, and a yield of 59%. Triglycidylglycerol (GLYG). The viscosity of GLYG is 32mPa. s, the epoxy equivalent obtained by titration was 91. The total chlorine content was 112 ppm, and the result of GC/MS analysis (Fig. 2) confirmed that it did not contain organic chlorine. (The chlorine is not derived from a compound having a carbon-chlorine bond).

[Production Example 4: Synthesis of pentaerythritol tetraglycidyl ether (PETG)]

Pentaerythritol tetraallyl ether (200 g, 0.67 mol) synthesized in the same manner as in Production Example 1 above, acetonitrile (220 g, 5.36 mol, manufactured by Pure Chemical Co., Ltd.), and methanol (100 g, 3.12 mol, manufactured by Pure Chemical Co., Ltd.) Into a 2-liter three-necked flask, a 50% by mass aqueous potassium hydroxide solution (manufactured by Wako Pure Chemical Industries, Ltd.) was added in a small amount to adjust the pH in the reaction system to about 10.5. When the reaction is completed and the reaction temperature does not exceed 40 ° C, a saturated aqueous solution of potassium hydroxide is added at any time to control the pH in the range of 10.75 to 10.25. A 45 mass% aqueous hydrogen peroxide solution (160 g, 2.12 mol, manufactured by Nippon Peroxide Co., Ltd.) was dropped for 18 hours. Into the reaction liquid, 2.11 g of sodium sulfite (manufactured by Wako Pure Chemical Industries, Ltd.) and 1000 g of toluene were added to temporarily stop the reaction, and the mixture was stirred at room temperature for 30 minutes to separate the aqueous layer from the organic layer. Thereafter, the organic layer was washed twice with 150 g of pure water, and the solvent was distilled off to obtain a reaction mixture.

Then, acetonitrile (220 g, 5.36 mol) and methanol (100 g, 3.12 mol) were added to the reaction mixture, and a small amount of a 50% by mass aqueous potassium hydroxide solution was added to adjust the pH of the reaction solution to about 10.5, and the internal temperature was 35 ° C. A 45 mass% aqueous hydrogen peroxide solution (125 g, 1.65 mol) was dropped for 28 hours so that the internal temperature did not exceed 45 °C. After the completion of the dropwise addition, 15.9 g of sodium sulfite and 800 g of toluene were added to stop the reaction, and the mixture was stirred at room temperature for 30 minutes to separate the aqueous layer from the organic layer. Thereafter, the organic layer was washed twice with 150 g of pure water to leave residual sodium sulfite and by-products. The impurities such as acetamide were removed, and by purging the solvent, pentaerythritol tetraglycidyl ether (PETG) was obtained in a purity of 90%, a yield of 176.04 g, and a yield of 72.4%. The viscosity of PETG is 166mPa. s, the epoxy equivalent obtained by titration was 98. The total chlorine content was 636 ppm, and it was confirmed by the SEC/MS analysis result (Fig. 3) that no organic chlorine was contained (the chlorine was not derived from a compound having a carbon-chlorine bond).

[Preparation of liquid resin composition]

The liquid epoxy resin compositions of Examples 1 to 21 and Comparative Examples 1 and 2 were prepared by mixing and dissolving the components in a 50 ° C ultrasonic water bath by the combination shown in Tables 1 to 4. The components used for the preparation of the liquid epoxy resin composition in the table are as follows.

(A) glycidyl ether compound

(A-1) 1,4-cyclohexanedimethanol diglycidyl ether obtained in Production Example 2 (CDMDG, total chlorine amount 5 ppm, viscosity 34 mPa.s)

(A-2) glycerol triglycidyl ether obtained in Production Example 3 (GLYG, total chlorine amount 112 ppm, viscosity 32 mPa.s)

(A-3) Pentaerythritol tetraglycidyl ether obtained in Production Example 4 (PETG, total chlorine amount 636 ppm, viscosity 166 mPa.s)

(A-4) Commercially available pentaerythritol polyglycidyl ether produced by the epichlorohydrin method (manufactured by Nagasechemtex Co., Ltd., Denacol (registered trademark) EX-411, viscosity 819 mPa.s, epoxy equivalent 233, total chlorine content 16.8%, Results of SEC/MS analysis (Figure 4) with carbon-chlorine bonds in the molecule)

(B) phenol resin-based hardener

(B-1) Phenolic novolac resin (manufactured by Showa Denko Co., Ltd., Shonol (registered trademark) BRG-556, softening point 77 to 83 ° C)

(B-2) Phenolic novolac resin (made by Showa Denko Co., Ltd., Shonol (registered trademark) BRG-564 G, softening point 60 ° C)

(B-3) Phenolic novolac resin (made by Showa Denko Co., Ltd., Shonol (registered trademark) BRG-555, softening point 67 to 72 ° C)

(B-4) Phenolic novolac resin (made by Showa Denko Co., Ltd., Shonol (registered trademark) BRG-558, softening point 93~98 °C)

(B-5) Triphenylmethane type phenol resin (made by Showa Denko Co., Ltd., Shonol (registered trademark) TRI-220, softening point 83 ° C)

(B-6) Liquid phenol novolak resin (manufactured by Showa Denko KK Co., Ltd., according to the method disclosed in JP-A-2012-67253)

(B-1) to (B-5) are solid at 25 ° C, and (B-6) is a liquid. The molecular weight distribution of (B-1)~(B-4) is shown in Fig. 5.

(C) hardening accelerator

(C-1) 2-ethyl-4-methylimidazole (Curezol (registered trademark) 2E4MZ, manufactured by Shikoku Chemical Industry Co., Ltd.)

(C-2) Triphenylphosphine (Beixing Chemical Industry Co., Ltd.)

[Production and Characterization of Hardened Materials]

Each of the resin compositions prepared in Examples 1 to 21 and Comparative Examples 1 and 2 was vacuum-degassed, and then poured into a cured product mold having a thickness of 3 mm, and heated in an oven at 150 ° C for 30 minutes to obtain a cured plate. use The obtained hardened board was subjected to the following measurement. The physical property values obtained are shown in Tables 1 to 4.

<Glass transition temperature (Tg)>

Determined by thermomechanical measurement (TMA). Using a TMA/SS6100 thermomechanical analyzer manufactured by SII NanoTechnology Inc., a test piece of 10 × 10 × 3 mm was used under the conditions of a temperature range of -10 to 250 ° C, a temperature increase rate of 5 ° C/min, and a load of 20.0 mN. Based on the straight line region before and after the inflection point of the transformation in the obtained expansion curve, the intersection temperature of each of the two straight lines is taken as the glass transition temperature.

<Linear expansion coefficient (CTE)>

Similarly to Tg, the linear expansion coefficient is determined by the expansion ratio in the Z-axis (thickness) direction as measured by TMA. Expanding the average value of the linear portion of the curve before and after the Tg obtained at α ₁ is (Tg-40 ℃) ~ the range of (Tg-20 ℃) of, α ₂ is (Tg + 20 ℃) ~ ( Tg + 40 ℃) The ranges are determined separately.

As shown in Tables 1 to 4, the glycidyl ether compound synthesized in Production Examples 2 to 4 and the solid phenol resin-based curing agent (B-1) were used. (B-5) The liquid epoxy resin composition of Examples 1 to 21, and the liquid of Comparative Example 1 using the glycidyl ether compound synthesized in Production Example 2 and the liquid phenol resin (B-6) The glass epoxy resin composition showed a significantly large glass transition temperature (Tg) of the cured product as compared with the case of using the same glycidyl ether compound. Further, Comparative Examples 12 to 17 of pentaerythritol tetraglycidyl ether (A-3) synthesized in Production Example 4 and pentaerythritol polyglycidyl ether (A-4) containing a commercially available high molecular weight component were used. In comparison, the Tg of the obtained cured product showed a significant large value. Further, in Comparative Example 16 which was relatively close to Comparative Example 2, Example 16 was lower in viscosity than Comparative Example 2, and Example 16 was shown to be advantageous in containing a large amount of additives.

From the above results, it is understood that the cured product of the liquid epoxy resin composition of the present invention is superior in heat resistance to the cured product of the resin composition using the conventional liquid phenolic curing agent.

[industrial use]

The liquid epoxy resin composition of the present invention has excellent heat resistance at a low viscosity, and is particularly preferably used for liquid sealing materials such as semiconductor sealing materials and underfill materials, and for conductive adhesives.

Claims (10)

A liquid epoxy resin composition which is a liquid epoxy resin composition containing (A) a glycidyl ether compound and (B) a phenol resin-based hardener, characterized by the aforementioned (A) glycidyl ether compound It is a liquid at 25 ° C and substantially does not contain a carbon-chloride bond, and the (B) phenol resin-based hardener is solid at 25 ° C, and the (B) phenol resin-based hardener contains a phenol novolak resin, A At least one of the group consisting of a phenol novolak resin, a triphenylmethane type phenol resin, and a dicyclopentadiene-modified phenol resin. The liquid epoxy resin composition according to claim 1, which contains no solvent or a reactive diluent. The liquid epoxy resin composition according to claim 1 or 2, further comprising (C) a curing accelerator. The liquid epoxy resin composition according to claim 1 or 2, wherein the (A) glycidyl ether compound is a polyglycidyl ether of an aliphatic polyol having 3 to 30 carbon atoms. The liquid epoxy resin composition according to claim 1 or 2, wherein the (A) glycidyl ether compound is obtained by reacting an allyl carbon-carbon double bond of an allyl ether compound with an oxidizing agent. The liquid epoxy resin composition according to claim 1 or 2, wherein the (A) glycidyl ether compound has a viscosity at 25 ° C of 1 mPa ‧ to 1000 mPa ‧ s. The liquid epoxy resin composition according to claim 1 or 2, wherein the (A) glycidyl ether compound comprises 1,4-cyclohexanedimethanol diglycidyl ether, trimethylolpropane Triglycidyl ether, Triglycidylglycerol, pentaerythritol tetraglycidyl ether, ditrimethylolpropane tetraglycidyl ether, diglycerol tetraglycidyl ether, dipentaerythritol hexa glycidyl ether, and sorbitol hexa glycidyl At least one of the groups consisting of ethers. The liquid epoxy resin composition according to claim 1 or 2, wherein the (B) phenol resin-based curing agent is contained in an amount of 20 to 300 parts by mass based on 100 parts by mass of the (A) glycidyl ether compound. The liquid epoxy resin composition according to claim 3, wherein the (C) hardening accelerator is selected from the group consisting of an imidazole compound and a derivative thereof, a phosphine compound and a derivative thereof, and a tertiary amine and a derivative thereof. At least one of the groups. The liquid epoxy resin composition according to claim 3, wherein the (C) hardening accelerator is contained in an amount of 100 parts by mass based on 100 parts by mass of the total of the (A) glycidyl ether compound and the (B) phenol resin-based curing agent. ~10 parts by mass.