JPH0873570A - Method for producing phenol aralkyl type resin and curable epoxy resin composition - Google Patents

Abstract

(57) [Summary] [Structure] A method for producing a phenol aralkyl resin, which comprises reacting phenol with divinylbenzene having a purity of 90% by weight or more. [Effect] Good heat resistance, moisture resistance and workability.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a phenol aralkyl resin having excellent performance as an epoxy resin curing agent and an epoxy resin composition containing the phenol aralkyl resin obtained by the method.

[0002]

2. Description of the Related Art Conventionally, phenolic compounds have been used as a curing agent for epoxy resins and are widely used in the fields of electrical and electronic materials. In these applications, curability, heat resistance and moisture resistance are particularly high. Materials with excellent balance of properties are required.

However, it is usually very difficult for an epoxy resin composition using a phenolic compound as an epoxy resin curing agent to balance these characteristics. Therefore, conventionally, for example, in JP-A-5-78457, an aromatic compound having two or more ethylenically unsaturated bonds represented by divinylbenzene in one molecule is disclosed as a composition having these properties. A technique of using a phenol aralkyl resin obtained by reacting with a phenol as a curing agent for an epoxy resin is disclosed.

[0004]

However, the above-mentioned Japanese Unexamined Patent Publication No.
Even with the technique described in Japanese Patent No. 78457, the properties as an epoxy resin curing agent for electrical and electronic materials described above have not always been satisfactory in terms of heat resistance, moisture resistance and workability.

The problems to be solved by the present invention are electric,
A method for producing a phenol aralkyl-type resin which is a cured product excellent in heat resistance and moisture resistance, which are particularly required in the electronic material field, and which is excellent in curability with an epoxy resin and has good workability, and the production method. An object of the present invention is to provide an epoxy resin composition having the above characteristics by using the resin obtained by the above as a curing agent.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have selected an aromatic compound having two or more highly pure ethylenically unsaturated bonds in one molecule. It was found that a phenol aralkyl type resin having not only improved heat resistance and humidity resistance but also good workability can be obtained by reacting with a phenol, and thus completed the present invention.

That is, the present invention is a method for producing a phenol aralkyl resin in which an aromatic compound containing a phenolic hydroxyl group is reacted with an aromatic compound containing at least two ethylenically unsaturated bonds having a purity of 90% by weight or more. ,
And an epoxy resin curable composition containing an epoxy resin and a phenolic compound as essential components, an aromatic compound having a phenolic hydroxyl group as the phenolic compound, and an ethylenically unsaturated bond having a purity of 90% by weight or more. The present invention relates to an epoxy resin composition comprising a phenol aralkyl resin obtained by reacting an aromatic compound containing at least two of the above.

As the phenolic compound used in the present invention, any known compounds can be used. For example, phenol, cresols, alkyl-substituted phenols such as p-tert-butylphenol, halogenated bromophenols and the like. Aromatic hydrocarbons containing two or more phenolic hydroxyl groups such as phenols, hydroquinone and resorcin, naphthols such as 1-naphthol, 2-naphthol, 1,6-dihydroxynaphthalene and 2,7-dihydroxynaphthalene, and bisphenol. Examples thereof include bisphenols such as F, bisphenol A, biphenol, and dihydroxydiphenyl ether. Where bisphenol A and bisphenol F
In the case of using, as an aspect of the produced polymer, not only an aralkyl bond derived from an aromatic compound having two or more ethylenically unsaturated bonds in one molecule but also an alkylidene bond specific to these bisphenols is contained at the same time. Will be done. These phenolic compounds may be used alone, or two or more kinds may be mixed and used.

Among these, it is preferable to use phenol, cresols, hydroquinone, resorcin, naphthols, bisphenol A and mixtures thereof, from the viewpoints of achieving high heat resistance and low water absorption of the cured product and economical efficiency. .

As the compound having at least two ethylenically unsaturated double bonds used in the present invention, any conventionally known compound can be used. For example, aromatic divinyl compounds such as divinylbenzene, alkyldivinylbenzene and diallyl phthalate. Among them, divinylbenzene is particularly preferable because of its excellent reactivity and workability. These compounds may be used alone or as a mixture of two or more kinds.

The aromatic compound having at least two ethylenically unsaturated double bonds used in the present invention has a purity of 9%.
It is extremely important that the content is 0% by weight or more. That is, usually, a reaction product of an aromatic compound having at least two ethylenically unsaturated double bonds and a phenol has good water resistance of the cured product because of the effect of reducing the water absorption rate due to the aralkyl group, The heat resistance of the cured product was markedly impaired with the glass transition point (Tg) as an index. However, the phenol aralkyl resin using an aromatic compound having at least two ethylenically unsaturated double bonds as a raw material and having a purity of 90% by weight or more has dramatically improved heat resistance of the cured product, As a result, a cured product having both heat resistance and moisture resistance, which are contradictory properties, is obtained. In addition, the epoxy resin composition obtained by mixing the phenol aralkyl resin with the epoxy resin described later has a short gel time at the time of curing, and the workability is remarkably improved.

Further, from the point that these effects are remarkable,
Aromatic compounds having at least two ethylenically unsaturated double bonds preferably have a higher purity, for example, 95
More preferably, it is at least wt%.

At least 2 ethylenically unsaturated double bonds are used in the production of the aralkylphenol resin according to the present invention.
The amount of the aromatic compound to be used is not particularly limited and should be appropriately selected depending on the phenols to be used to determine the optimum value, but usually 0.2 to 1 relative to the number of moles of the phenols. It is preferably 0.0 mol.

At least 2 ethylenically unsaturated double bonds
The reaction temperature of the compound with the phenol and the phenol compound is not particularly limited, but is preferably in the range of 50 to 150 ° C.,
It is particularly preferable to carry out at 70 to 120 ° C.

The reaction conditions in the production method of the present invention are not particularly limited, but it is preferable to carry out the reaction in an inert solvent or in the molten state of solvent-free phenols in the presence of an acid catalyst.

Examples of the acid catalyst used in this case include Lewis acids such as aluminum chloride, stannic chloride and boron trifluoride ether complex, inorganic acids such as sulfuric acid, hydrochloric acid and phosphoric acid, benzenesulfonic acid, Organic sulfonic acids such as paratoluene sulfonic acid, acetic acid, oxalic acid,
An organic carboxylic acid such as maleic acid can be used, and two or more kinds of catalysts can be mixed and used.

As the acid catalyst, Lewis acids, which are Friedel-Crafts catalysts, strong inorganic acids, and organic sulfonic acids, can be obtained because the reaction can be completed in a short time and a phenol aralkyl resin having a narrow molecular weight distribution can be obtained. Preference is given to using.

The amount of the acid catalyst used is not particularly limited and varies depending on its type, but the reaction can be completed in a short time, the reaction is mild, and the reaction control is easy.
0.1 to 5.0 parts by weight is preferable per 100 parts by weight of phenols.

As the inert solvent, any conventionally known solvent can be used, and examples thereof include toluene, xylene, dimethylformamide, dimethylsulfoxide, solvesso and alcohols. When a solvent is used, those capable of dissolving all of phenols, compounds having at least two ethylenically unsaturated double bonds, reaction catalyst and phenol aralkyl resin as a reaction product are suitable.

The purpose of the phenol aralkyl resin of the present invention is to obtain a resin having a structure in which phenols and an aromatic compound having at least two ethylenically unsaturated double bonds are added, and the α-position of the vinyl bond is The polycondensation reaction proceeds while binding to the aromatic ring of the phenol to produce a phenol aralkyl resin.

The structure of the thus-obtained phenol aralkyl resin varies depending on the raw materials used and is not particularly limited, but it is specifically represented by the following formula (1).

[0022]

Embedded image

(In the formula (1), R represents a methyl group, an ethyl group or a propyl group, X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a halogen atom, and n is 0 to 6). An integer, i is an integer of 1 or 2, and j is an integer of 1 to 4, respectively.)

The melt viscosity is not particularly limited, but when it is used as a casting material after mixing with an epoxy resin, for example, a low viscosity resin is preferable.
A resin having a melt viscosity at 0 ° C. of preferably 50 poise or less is used. On the other hand, the resin of the present invention has excellent solubility in a solvent, and when it is used by dissolving it in a solvent, a resin having a higher molecular weight and a higher viscosity can be used.

The epoxy resin composition of the present invention contains the phenol aralkyl resin described in detail and the epoxy resin as essential components.

The epoxy resin used here is not particularly limited, but for example, bisphenol diglycidyl ether type epoxy resin starting from bisphenols such as bisphenol F and bisphenol A, phenol novolac resin, orthocresol novolac resin.・ Novolak type polyfunctional epoxy resin starting from brominated phenol novolac resin, polyvalent epoxy resin starting from polyhydric phenols, polyvalent epoxy resin starting from phenol aralkyl resin, phenol and dicyclopentadiene Polyhydric epoxy resin made from condensation-produced phenolic resin and polyhydric epoxy resin made from petroleum resin containing phenols as components, further diphenylmethanediamine tetraglycidyl ether, cyclo Hexane diamine tetra glycidyl glycidyl amine type polyfunctional epoxy resins such as ether, polyethylene glycol diglycidyl ether, epoxidized SBR, aliphatic epoxy resins such as epoxidized soybean oil.

The mixing ratio of the epoxy resin composition varies depending on the composition, but it is common to mix the ratio of the phenolic hydroxyl group of the phenol aralkyl resin as the curing agent and the epoxy group of the epoxy resin in an equivalent ratio. .

In addition, in the epoxy resin composition, a curing accelerator may be used in combination in order to accelerate curing cross-linking. As the curing accelerator, any of those generally used can be used, and examples thereof include imidazoles such as N-methylimidazole, tertiary amines such as triethylamine, and organic strong agents such as diazabicycloundecane. Examples thereof include basic compounds and phosphorus compounds such as triphenylphosphine.

In the epoxy resin composition of the present invention,
The phenol aralkyl resin obtained by the above-mentioned production method can be used alone as an epoxy resin curing agent, but may be used in combination with a known and commonly used epoxy resin curing agent, if necessary.

Known epoxy resin curing agents include:
For example, dicyandiamide, polyalkylene polyamine,
Examples thereof include polyamide polyamines, Mannich products, phenol novolac resins, orthocresol novolac resins, naphthol novolac resins, phenol aralkyl resins, and polyphenol compounds other than the above.

If necessary, various additives such as a filler, a coupling agent, a flame retardant, a lubricant, a release agent, a plasticizer, a coloring agent, and a thickener are added to the epoxy resin composition of the present invention. You may use it.

The epoxy resin composition thus obtained is used as an encapsulant for semiconductors for surface mounting by taking advantage of its excellent heat resistance and water resistance. For example, a copper-clad laminate and its precursor are used. It is possible to exhibit excellent performance in the field of application where conventional normal novolac resins have been used as epoxy resin curing agents such as prepregs, coating materials, coating agents and molding materials.

[0033]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

The gel times in Examples 1 to 4 and Comparative Examples 1 and 2 were measured as follows. [Measurement of gel time] The phenol aralkyl resin obtained in each of the Examples and Comparative Examples was treated with 60% of methyl ethyl ketone.
As a solution, o-cresol type epoxy resin (Dainippon Ink and Chemicals, Inc. EPICLON N-665 epoxy equivalent: 209 g /
eq) in 60% methyl ethyl ketone and triphenylphosphine
After mixing well with 1 phr, gel time was measured on a cure plate at 175 ° C.

Example 1 In a four-necked 1 liter flask equipped with a stirrer, condenser, thermometer and dropping funnel, 235 g of phenol was added.
(2.5 mol) and 2.3 g of paratoluenesulfonic acid as a catalyst were added, and the temperature was raised to 90 ° C. 96% divinylbenzene is dripped little by little from the dropping funnel and 110 ° C.
The temperature is raised by utilizing heat generation. While maintaining the temperature at 105 to 115 ° C, 96% divinylbenzene (total 203 g, 1.5 mol) was added dropwise over about 2 hours, and then the reaction was carried out for 1 hour. 0.95 g of 49% sodium hydroxide aqueous solution is added thereto to neutralize the catalyst, 350 g of xylene is added, and then water is removed by azeotropic dehydration. When water is no longer distilled off, the internal temperature is cooled to 90 ° C. and the insoluble matter is removed by filtration. Xylene is removed from the filtrate by distillation, and a phenol / divinylbenzene (DVB) condensation resin 42
0 g was obtained. Hereinafter, this resin is abbreviated as "resin A".

The property values of the resin A thus obtained were as follows. Melt viscosity: 3.1 poise (150 ° C.) Hydroxyl equivalent: 184 g / eq. Then, the gel time was measured using the resin A. The results are shown in Table 1.

Example 2 Instead of the phenol used in Example 1, m-cresol 270 was used.
By the same operation except that g (2.5 mol) is used, m
Obtained 450 g of cresol / DVB condensation resin. Hereinafter, this resin is abbreviated as "resin B".

The properties of the obtained resin B were as follows. Melt viscosity: 1.7 poise (150 ° C.) Hydroxyl equivalent: 200 g / eq. Then, the gel time was measured using the resin B. The results are shown in Table 1.

Example 3 In a four-necked 2 liter flask equipped with a stirrer, condenser, thermometer and dropping funnel, 288 g of α-naphthol was added.
(2.0 mol), 350 g of xylene and 2.3 g of paratoluenesulfonic acid as a catalyst were added, and the temperature was raised to 90 ° C. From the dropping funnel, 96% divinylbenzene is dropped little by little and the temperature is raised to 110 ° C. by utilizing heat generation. 1
96 over 2 hours while maintaining the temperature at 05-115 ° C
% Divinylbenzene (total 203 g, 1.5 mol) was added dropwise and then reacted for 1 hour. 0.95 g of 49% sodium hydroxide aqueous solution is added thereto to neutralize the catalyst, and water is removed by azeotropic dehydration with xylene. When water is no longer distilled off, the internal temperature is cooled to 90 ° C. and the insoluble matter is removed by filtration. Xylene was removed from the filtrate by distillation, and α-
Naphthol / divinylbenzene (DVB) condensation resin 4
80g was obtained. Hereinafter, this resin is abbreviated as “resin C”.

The properties of the obtained resin C were as follows. Melt viscosity: 5.2 poise (150 ° C.) Hydroxyl equivalent: 252 g / eq. Then, the gel time was measured using the resin C. The results are shown in Table 1.

Example 4 Bisphenol A was used instead of α-naphthol in Example 3.
(BPA) 456 g (2.0 mol) and xylene 600 g
628 g of BPA / DVB condensation resin was obtained by the same operation except that was used. Hereinafter, this resin is referred to as "resin D"
Abbreviated.

The properties of the obtained resin D are as follows. Melt viscosity: 7.1 poise (150 ° C.) Hydroxyl equivalent: 133 g / eq. Then, the gel time was measured using the resin D. The results are shown in Table 1.

Comparative Example 1 In place of 203 g of 96% divinylbenzene in Example 1, 241 g of 81% divinylbenzene was used.
By the same operation as in Example 1, 440 g of phenol / DVB condensation resin was obtained. Hereinafter, this resin is abbreviated as "resin E".

The properties of the resin E thus obtained were as follows. Melt viscosity: 2.0 poise (150 ° C.) Hydroxyl equivalent: 199 g / eq. Then, the gel time was measured using the resin E. The results are shown in Table 1.

Comparative Example 2 Except that 203 g of 96% divinylbenzene in Example 2 was replaced with 286 g of 81% divinylbenzene,
By the same operation as in Example 1, m-cresol / DV
470 g of B condensation resin is obtained. Hereinafter, this resin is abbreviated as "resin F".

The properties of the resin F thus obtained were as follows. Melt viscosity: 1.7 poise (150 ° C.) Hydroxyl equivalent: 205 g / eq. Then, the gel time was measured using the resin F. The results are shown in Table 1.

[0047]

[Table 1]

[0048]

[Table 2]

Examples 5-8 and Comparative Examples 3 and 4 1 equivalent of the phenol aralkyl resin obtained in Examples 1 to 4 and Comparative Examples 1 and 2 and an o-cresol type epoxy resin (manufactured by Dainippon Ink and Chemicals, Inc.) EPICLON N-665 Epoxy equivalent: 209 g / eq) 1 equivalent is sufficiently mixed in a molten state, and triphenylphosphine is added as a curing accelerator there.
After adding 2.09g and mixing well, after casting 175 ℃
Cure in 5 hours. The cured sample was cut into an appropriate shape, the glass transition point (Tg) was measured by TMA, and the water absorption rate was measured. The results are shown in Table 3.

The water absorption was measured according to the following measuring method.

[Measurement of Water Absorption] The water absorption of the cured test piece was measured at 85 ° C. and 85% R.A. H. Was measured. The test results are shown in Table 2.

[0052]

[Table 3]

[0053]

INDUSTRIAL APPLICABILITY According to the present invention, an epoxy resin composition which is a cured product having excellent heat resistance and moisture resistance, which are particularly required in the fields of electric and electronic materials, and which is excellent in curability and has good workability. In particular, as a curing agent for an epoxy resin, it is possible to provide a method for producing the resin, which can easily obtain a phenol aralkyl resin exhibiting the above-mentioned properties.

Claims (6)

[Claims] 1. A method for producing a phenol aralkyl resin, which comprises reacting an aromatic compound containing a phenolic hydroxyl group with an aromatic compound containing at least two ethylenically unsaturated bonds having a purity of 90% by weight or more. 2. The presence of an acid catalyst in an inert solvent containing an aromatic compound containing a phenolic hydroxyl group and an aromatic compound containing at least two ethylenically unsaturated bonds having a purity of 90% by weight or more in an inert solvent. The method according to claim 1, wherein the reaction is carried out below. 3. The method according to claim 2, wherein the reaction is carried out at 50 to 150 ° C. 4. The method according to claim 1, 2 or 3, wherein the aromatic compound having a phenolic hydroxyl group is phenol, cresol, naphthol or bisphenol. 5. The method according to claim 4, wherein the aromatic compound containing at least two ethylenically unsaturated bonds is divinylbenzene. 6. A curable epoxy resin composition comprising an epoxy resin and a phenolic compound as essential components,
Use of a phenol aralkyl resin obtained by reacting an aromatic compound containing a phenolic hydroxyl group with an aromatic compound containing at least two ethylenically unsaturated bonds having a purity of 90% by weight or more as the phenolic compound. A curable epoxy resin composition comprising: