JPH11255868A - Preparation of phenol aralkyl resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process to prepare a phenol aralkyl resin of high purity suitable as a raw material for an epoxy hardener or an epoxy resin for electronic materials. SOLUTION: There is provided a process to prepare a phenol aralkyl resin by subjecting phenols and a xylylene compound having a halomethyl group (1): R1 -(CH2 X)2 or a mixture of the same with a xylylene compound (2): R2 -(CH2 OR3 )2 such as a glycol ether or the like to a condensation reaction in the presence of an acid catalyst, wherein the molar ratio of (1) to (2) is in the range of 100/0 to 40/60, water is added as a reaction initiator and hydrogen halide evolved by hydrolysis is employed as a catalyst for the initiation of the condensation reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to various binders,
The present invention relates to a method for producing a phenolic polymer useful as a coating material, a laminate material, a molding material, and the like. In particular, the present invention relates to a production method for efficiently obtaining a high-purity polymer with few impurities, which is suitable as an epoxy curing agent for an electronic material or a raw material of an epoxy resin.

[0002]

2. Description of the Related Art Phenol formaldehyde resin is widely used for various purposes as an inexpensive heat-resistant resin. In addition, various resins having different structures have been developed for the purpose of improving the properties of ordinary phenolic resins, and are already known.

[0003] In particular, a polymer obtained by a condensation reaction of an aralkyl compound such as α, α'-dimethoxy-p-xylene with a phenol described in Japanese Patent Publication No. 47-15111 is a phenol aralkyl resin.
Due to its excellent heat resistance, electrical properties, and moisture and chemical resistance, it is widely used for various applications. Further, in recent years, phenol aralkyl resins have been widely used as curing agents in the field of encapsulants which require moisture resistance, as ICs are becoming denser, smaller and thinner, and being surface mounted.

[0004] Regarding the method for producing the phenol aralkyl resin, many methods have been disclosed. As the most common production method, for example, Japanese Patent Publication No. 47-151
Japanese Patent Publication No. 11 and JP-B-48-10960 describe a method in which an excess mole of phenol is reacted with an aralkyl halide or an aralkyl alcohol derivative in the presence of a Friedel-Crafts catalyst or diethyl sulfate. Further, p-toluenesulfonic acid (JP-B-63-238129), methanesulfonic acid (JP-B-63-238129) and the like are also disclosed as catalysts.

[0005]

However, according to the methods disclosed in these publications, it is difficult to completely separate the acid catalyst used in the reaction from the reaction product, and the obtained resin is slightly acidic. Contains. Therefore, it cannot be used as it is for applications in which impurities are particularly disliked, and it is necessary to remove the catalyst by washing with water. In addition, there is a disadvantage that the remaining acidic substance causes problems such as a change in molecular weight distribution, an increase in viscosity and a regeneration of phenolic monomers in the production process, and the quality is not stable.

As a method for solving this problem, a method of reacting an aralkyl compound with a phenol while adding hydrochloric acid has been reported (JP-A-5-247183). According to this, it is possible to prevent a decrease in physical properties due to remaining acidic substances, but in order to complete resinification while controlling the reactivity, it is necessary to continuously add an appropriate amount of hydrochloric acid during the reaction. And the operation is complicated.

Further, JP-A-6-100667 and Chemical Economics (September 1997, pp. 37-41) disclose the reaction of phenols with aralkyl dihalides such as α, α′-dichloro p-xylene without a catalyst. Methods have been reported. In the above report, the mechanism by which the reaction proceeds without a catalyst is explained by the equilibrium of aralkyl dihalide itself. That is, at a temperature of 70 ° C. or higher, there is an equilibrium in which some aralkyl dihalides dissociate into benzyl cations and halide ions, and the benzyl cations generated here react with phenols, which explains that resinification proceeds. I have. This method is based on the premise that benzyl cation is generated by dissociation of aralkyl dihalide, which reacts with phenols. Therefore, the aralkyl compound as a raw material is limited to aralkyl dihalide, and aralkyl ethers and aralkyl glycol cannot be used. The report does not disclose any aralkyl compounds other than these aralkyl dihalides.

The present invention has been made in view of the above circumstances, and provides a method for efficiently producing a phenolic resin and a phenolaralkyl-based resin having a high purity with a small amount of impurities and a stable viscosity. Its purpose is to

[0009]

Means for Solving the Problems In order to achieve the above object, the present inventors have conducted intensive studies on the type of catalyst and the method of removal. By using a certain amount of xylylene compound that generates hydrogen and adding water as a reaction initiator, there is no decrease in physical properties due to the remaining acidic catalyst substance, the operation is simple, and the range of choice of raw material xylylene compound can be selected. Have been found, a method for producing a phenol aralkyl-based resin having high purity and stable quality has been achieved, and the present invention has been achieved.

That is, the present invention relates to a phenol and a xylylene compound represented by the following general formula (1) or a xylylene compound represented by the following general formula (2) R _1- (CH ₂ X) _2. ·· (1) R _2- (CH ₂ OR ₃ ) ₂ ·· (2) (wherein R ₁ and R ₂ are the same or different, phenylene group, alkyl-substituted phenylene group, diphenylene group, diphenylene oxide group, A naphthylene group, X is a halogen atom, and R ₃ is a hydrogen atom or a C ₁ -C ₄ alkyl group) in the presence of an acid catalyst to form a phenol aralkyl resin. In the production method, the molar ratio of (1) / (2) is in the range of 100/0 to 40/60, water is added as a reaction initiator, and a hydrogen halide generated by hydrolysis is subjected to a condensation reaction. Starting It is characterized by using as the medium, a method for producing a phenol aralkyl resin. Hereinafter, the present invention will be described in detail.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a xylylene compound having a halomethyl group represented by the general formula (1) is used as a raw material as an essential component, and is generated by adding water as a reaction initiator. It is characterized by performing resinification using HCl as an acid catalyst.

The HCl generated during the reaction is finally volatilized out of the system and removed, so that the obtained polymer has little purity of acidic components, high purity, and extremely high quality such as viscosity. Stabilize.

Specific examples of the xylylene compound represented by the general formula (1) (hereinafter simply referred to as (1)) include di (chloromethyl) benzene, di (bromomethyl) benzene, di (chloromethyl) biphenyl, and di (chloromethyl) biphenyl. (Chloromethyl) naphthalene, di (chloromethyl) biphenyl ether and the like. Particularly, dichloromethylbenzene is preferred. Substitution position of -CH ₂ X in the case of di (chloromethyl) benzene, ortho, meta, may be any of para,
Generally preferred is the para or meta position, and mixed systems of the meta and para positions are also preferred.

As the xylylene compound, in addition to the halomethyl compound (1), glycols or alkoxys represented by the general formula (2) (hereinafter referred to as (2)) can be used in combination. Examples of such a xylylene compound include xylylene glycol, xylylene glycol dimethyl ether, xylylene glycol diethyl ether, xylylene glycol dipropyl ether, xylylene glycol dibutyl ether, xylylene glycol monomethyl ether, and xylylene glycol monoethyl ether. Xylylene glycol mono- or di-lower alcohol ether and the like. Particularly, xylylene glycol, xylylene glycol dimethyl ether and the like are preferable. The substitution position of —CH ₂ OR _{3 in} the above formula (2) may be any of ortho, meta and para,
Generally preferred is the para or meta position, and mixed systems of the meta and para positions are also preferred.

The molar ratio of (1) / (2) is from 100/0 to 40/60, preferably from 80/20 to 40/60. That is, (1) alone or as a raw material, or (1) and (2) containing up to 40% of (2) with respect to the mixture.
Can be used. (2) is not an essential component, but (1) is a solid substance, whereas (2)
Is a liquid substance, it is more advantageous to use a mixture containing a small amount of (2) from the viewpoint of the reaction operation, and it is advantageous to set the above molar ratio to 80/20 or less. However, when this ratio is less than 40/60, the functional groups of the xylylene compound (2) having relatively low reactivity are not completely reacted and are left in the resin. In the present invention, even if a mixture of (1) and (2) contains 40% or more of (1), HCl generated by adding water acts as an acid catalyst, and (2) The xylylene compound is also converted into a resin by reaction with phenol, so that the degree of freedom in selecting the raw materials is increased, and by using a mixture having fluidity as a raw material according to the purpose, the reaction can be performed in an easily handled state. Can be.

The phenols used in the present invention include one or two hydroxyl groups bonded to an aromatic ring.
Various monocyclic, polynuclear, or condensed polycyclic aromatic compounds having at least one compound can be used. Specific examples include substituted phenols such as phenol, cresol, xylenol, ethylphenol, butylphenol, phenylphenol, and halogenated phenol; resorcinol, catechol, dihydroxybiphenyl, tetramethyldihydroxybiphenyl, bisphenol A, bisphenol S,
Dihydric phenols such as bisphenol F; condensed polycyclic phenols such as α-naphthol, β-naphthol, and naphthalene diol; one or more of these can be used. Of these phenols, preferably phenol, o-cresol, p-
Cresol, p-phenylphenol, catechol,
4,4'-dihydroxybiphenyl, α- or β-naphthol are used.

The molar ratio of the xylylene compound to the phenol is preferably 0.1 to 0.8. If the molar ratio is less than 0.1, unreacted phenols increase and the yield decreases, which is not preferable. If it exceeds 0.8, the molecular weight of the produced resin increases, the softening temperature rises, and the fluidity at the time of molding tends to decrease, which is not preferable. A more desirable ratio is 0.2 to 0.7.

Water must be present as a reaction initiator when initiating the reaction between the phenol and the xylylene compound. The required amount of water is preferably 100 ppm or more based on the total amount of the general formulas (1) and (2), which are xylylene compounds. Water may be added to the system in a necessary amount or more before the start of the reaction.

The reaction between the phenols and the xylylene compound is usually carried out at 80 to 180 ° C, preferably at 110 to 160 ° C.
The temperature range is as follows. The reaction time is generally between 1 and 10 hours.

When reacting a phenol with a xylylene compound, the reaction may be carried out by simultaneously adding the xylylene compound or, if necessary, by sequentially adding the xylylene compound.

This reaction is carried out by using HCl formed by condensation.
The reaction continues. After the condensation reaction is completed,
HCl remaining in the system is distilled off under reduced pressure together with unreacted phenols, or by an appropriate method such as distillation under reduced pressure while blowing in an inert gas.

The method of the present invention can be used without any problem even in applications where impurities are extremely strictly regulated, such as an epoxy resin curing agent for semiconductor encapsulation. In addition, even if the thermal stabilization of the polymer is insufficient and it receives heat history during use,
Since quality fluctuations such as an increase in viscosity, an increase in molecular weight distribution, and regeneration of unreacted phenol can be completely ignored, a resin which is extremely stable in quality can be obtained.

[0023]

The present invention will be described below in detail with reference to examples. Example 1 Phenol 59950 was placed in a glass reactor equipped with a stirrer, a condenser, and a nitrogen gas inlet tube.
Parts by weight, 17 parts by weight of water, 27525 parts by weight of p-xylylene glycol dimethyl ether and 29017 parts by weight of 1,4-di (chloromethyl) benzene were heated while stirring under a nitrogen gas stream. The reaction was carried out while removing HCl and methanol generated from the system while raising the temperature from 70 ° C. to 120 ° C. over 2 hours. Further 140
After performing the reaction at 2 ° C. for 2 hours, the temperature was reduced from 110 ° C. to 150 ° C. while bubbling nitrogen under reduced pressure of 50 torr or less.
The mixture was distilled under reduced pressure for 6 hours while elevating the temperature to remove unreacted phenol and slightly remaining HCl in the system to obtain 69940 parts by weight of the desired product. Table 1 shows the properties of the obtained phenol aralkyl resin.

Example 2 The reactor used in Example 1 was
After charging 58035 parts by weight of 1,4-di (chloromethyl) benzene, phenol 5995 melted at 80 ° C.
0 parts by weight and 23 parts by weight of water were added. The reaction was performed while removing HCl generated outside the system while heating the temperature from 70 ° C. to 120 ° C. over 2 hours under a nitrogen gas stream with stirring. After a further 2 hours of reaction at 140 ° C., 50
Under a reduced pressure of not more than torr, while bubbling nitrogen,
The mixture was distilled under reduced pressure for 6 hours while the temperature was raised from 10 ° C. to 150 ° C. to remove unreacted phenol and slightly remaining HCl in the system to obtain 69920 parts by weight of the desired product. Table 1 shows the properties of the obtained phenol aralkyl resin.

Comparative Example 1 The reactor used in Example 1 was
59950 parts by weight of phenol and 55050 parts by weight of p-xylene glycol dimethyl ether were added. Under a nitrogen gas stream, 230 parts by weight of p-toluenesulfonic acid monohydrate was added as an aqueous solution at 80 ° C. while stirring, and 12 parts by weight were added.
The reaction was carried out for 4 hours while removing methanol generated at 0 to 140 ° C outside the system. Thereafter, under a reduced pressure of 50 torr or less, the temperature is reduced from 110 ° C. to 1 while bubbling nitrogen.
The mixture was distilled under reduced pressure for 6 hours while the temperature was raised to 50 ° C. to remove unreacted phenol in the system to obtain 69915 parts by weight of a phenol aralkyl resin. Table 1 shows the properties of the obtained resin.

Comparative Example 2 The reactor used in Example 1 was
5803 parts by weight of 1,4-di (chloromethyl) benzene was added to p-xylylene glycol dimethyl ether 49545
After the mixture dissolved in parts by weight was charged, 59950 parts by weight of phenol melted at 80 ° C. and 22 parts by weight of water were added. The reaction conditions and the distillation conditions under reduced pressure were the same as in Example 1 to obtain 69950 parts by weight of a phenol aralkyl resin. Table 1 shows the properties of the obtained phenol aralkyl resin.

[0027]

[Table 1]

As shown in Table 1, no impurities such as acidic substances and unreacted xylylene compounds were detected in the resins obtained in all Examples, and the resins were of high purity. 160 ° C
No change such as an increase in molecular weight distribution and phenol was observed even after the heat treatment for 10 hours, indicating that the composition was excellent in thermal stability. On the other hand, in the resin obtained in Comparative Example 1 using p-toluenesulfonic acid as the catalyst, the acidic substance of the catalyst remained, and the pH of the extraction water also showed a low value. In addition, the thermal stability was poor, and the heat treatment at 160 ° C. for 10 hours increased the molecular weight distribution, significantly increased the melt viscosity, and increased unreacted phenol to 3.4 wt%. On the other hand, unreacted xylylene glycol dimethyl ether was detected in the resin of Comparative Example 2 using a mixture containing a small amount of di (chloromethyl) benzene as a raw material, and the reaction was not completed.

[0029]

According to the present invention, a simple operation of a high-purity phenol aralkyl-based resin which has a small amount of impurities due to residual catalyst, is stable in quality, and is suitable for use as an epoxy resin curing agent for semiconductor encapsulation. Can be obtained efficiently.
In addition, a raw material xylylene compound for resin production can be widely selected.

Claims (2)

[Claims] 1. A phenol and a xylylene compound represented by the following general formula (1), or a phenol and a xylylene compound represented by the following general formula (2): R ₁ — (CH ₂ X) _2. 1) R ₂ — (CH ₂ OR ₃ ) ₂ ... (2) (wherein R ₁ and R ₂ are the same or different phenylene groups, alkyl-substituted phenylene groups, diphenylene groups, diphenylene oxide groups, and naphthylene groups) X is a halogen atom, and R ₃ is a hydrogen atom or a C ₁ -C ₄ alkyl group) in the presence of an acid catalyst to produce a phenol aralkyl resin. Wherein the molar ratio of (1) / (2) is in the range of 100/0 to 40/60, and water is added as a reaction initiator, and hydrogen halide generated by hydrolysis is used as a catalyst for initiating a condensation reaction. Use as Wherein the bets method for producing a phenol aralkyl resin. 2. The method according to claim 1, wherein the amount of water added as a reaction initiator is at least 100 ppm by weight based on the total amount of the xylylene compounds of the general formulas (1) and (2). A method for producing a phenol aralkyl resin.