JPH0816150B2 - Alkylphenol aralkyl resin composition and method for producing the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to a novel low molecular weight alkylphenol aralkyl resin composition and a method for producing the same.

This alkylphenol aralkyl resin composition can be used as a raw material for an epoxy resin or a curing agent for other epoxy compounds. Further, a cured product using this alkylphenol aralkyl resin composition can be used in various fields such as casting, laminating, coating, and semiconductor encapsulation.

[Conventional technology]

The use of phenolic compounds as epoxy resins or their curing agents in matrix resins for heat-resistant composite materials, heat-resistant adhesives, etc. has become more and more diverse in recent years and has become industrially important. It is required to add high performance.

For example, composite materials, adhesives, etc. are required to withstand an instantaneous impact such as stress concentration as external stress. For this reason, elastically deforming like rubber ideally attracts attention as an important factor. As a criterion for determining such elastic deformation, the elongation at break of the matrix resin is particularly important. The larger the elongation, the more the defects of the reinforcing agent such as glass fiber and carbon fiber required for the composite material can be compensated. That is, the strength of the entire composite material is improved.

[Problems to be solved by the invention]

The conventional phenol aralkyl resins used for the above-mentioned applications are each composed of a composition obtained by subjecting a phenol and an aralkyl ether to a condensation reaction so that substantially no unreacted material remains.

Therefore, the amount of phenol used per mol of the bifunctional aralkyl ether is limited to the range of 1.3 to 3 mol.

Resins obtained in this range include, for example, Zyloc 225 (trade name) manufactured by Albright Wilson Co., Ltd., and Milex XL-225 (trade name) manufactured by Mitsui Toatsu Chemical Co., Inc.

However, the phenol aralkyl resin obtained by the above-mentioned molar ratio range of phenol has a large molecular weight of several thousands to tens of thousands, and has a high softening point of 75 to 95 ° C. Therefore, it is still unsatisfactory in terms of fluidity and performance. is there. For this reason, not only is it inefficient in terms of workability, but also the inherent mechanical properties, especially the elongation at break, have not reached the level required for composite materials and the like.

Further, such composite materials and adhesives are generally wet-impregnated and molded, and if the epoxy resin is liquid at room temperature or has a low melting point, use of an unnecessary organic solvent or heating and melting in an originally unnecessary state No work is required, resulting in reduced usage and improved workability.

Further, in these matrix resins, long-term storage stability is also important, and it is required that deterioration due to oxygen in the air is small. This oxidation resistance mainly comes from the structure of the resin, and the phenol novolac resin structure cannot solve this problem.

Recently, among these required elements, epoxidized phenol aralkyl resin for the purpose of improving heat resistance as well as mechanical properties, oxidation resistance, moisture resistance, etc.
-13782, JP 60-112813) and the use of phenol aralkyl resins as curing agents for other epoxy compounds (JP 59-105018).

For example, the phenol aralkyl resin used in the resin composition for encapsulation described in JP-A-59-105018 uses "a phenol aralkyl resin represented by the general formula (a) in which n = 1 or more. However, as a specific example, only Zyloc 225 (trade name) manufactured by Albright Wilson Co. is used. Although the detailed composition of Zyloc 225 is unknown, it is clear that it is not a low molecular weight phenol aralkyl resin composition that can solve the above problems.

A phenol aralkyl resin that can sufficiently solve the problems described above and a method for producing the same have not been known yet. However, the present inventors have found that the problem can be solved by using a certain type of low molecular weight phenol aralkyl resin, and applied for the invention first (Japanese Patent Application No. 62-070282).

The present invention has been made in view of the above problems, the object is to show sufficient performance in water resistance, oxidation resistance,
Matrix resin for heat-resistant composite materials, which has excellent mechanical properties such as impact resistance, workability, and also has sufficient heat resistance,
It is to provide an alkylphenol aralkyl resin composition as a raw material of an epoxy resin useful as a heat-resistant adhesive or the like or a curing agent thereof, and a method for producing the same.

[Means for solving problems]

The present inventors have completed the present invention as a result of earnest studies to achieve the above object.

That is, the invention has the general formula (a) (However, in the formula, R ¹ represents hydrogen or an alkyl group having 1 to 9 carbon atoms, R ² represents an alkyl group having 1 to 9 carbon atoms,
n represents an integer of 0 to 5 and contains n = 0 in an amount of 50 mol% or more. ) An alkylphenol aralkyl resin composition represented by: and a general formula (b) (However, R ³ in the formula represents a lower alkyl group having 4 or less carbon atoms.) The α, α′-dialkoxy-p-xylene represented by the general formula (c) (However, R ¹ in the formula represents hydrogen or an alkyl group having 1 to 9 carbon atoms, and R ² represents an alkyl group having 1 to 9 carbon atoms.) A method for producing an alkylphenol aralkyl resin composition represented by the general formula (a), characterized in that unreacted alkylphenol is separated from the resulting reaction product.

The epoxidized product using the alkylphenol aralkyl resin composition of the present invention as a raw material gives a good cured product when combined with various curing agents. For example, liquid diaminodiphenylmethane (MDA) (trade name Epicure Z,
(Made by Shell Chemical Co., Ltd.) as a curing agent, when compared with an epoxy resin having bisphenol A as a skeleton,
Excellent tensile strength and elongation of about 1.3 times. Further, since it has an alkyl group on the benzene ring of the main chain, the heat resistance is improved as compared with the case where the phenol aralkyl resin of Japanese Patent Application No. 62-070282 is used as a curing agent.

Further, the epoxidized product using the alkylphenol aralkyl resin composition of the present invention as a raw material is also characterized by being liquid at room temperature or having a low melting point. For this reason, operations such as compounding, coating, and impregnation are extremely good, and a uniform cured product can be obtained.

Moreover, even when the alkylphenol aralkyl resin composition of the present invention is used as a curing agent for various epoxy resins, the same effects as described above are exhibited. For example, the tensile strength and elongation are improved as compared with the case where other conventional effect agents are used, and the heat resistance is improved as compared with the case where the phenol aralkyl resin of Japanese Patent Application No. 62-070282 is used as a curing agent.

In order to obtain the above effects, the repeating unit n of the alkylphenol aralkyl resin composition needs to be 5 or less. In addition, it contains substantially n = 0 as a main component, that is, contains 50 mol% or more of n = 0. Further, R ¹ and R ^{2 in} the case of an alkyl group have 1 to 9 carbon atoms.

Specific examples of the method for obtaining the alkylphenol aralkyl resin composition represented by the general formula (a) having the range of the repeating unit n as described above will be described below.

First, the alkylphenol represented by the general formula (c) is 4 mol or more, preferably 5 to 20 mol, more preferably 1 mol of the α, α'-dialkoxy-p-xylene represented by the general formula (b). Is added in the range of 6 to 15 moles,
In the presence of an acid catalyst, the temperature is raised as it is and the reaction is performed at the temperature described below. The alcohol produced as the reaction proceeds is trapped outside the system. If necessary, a trace amount of alcohol remaining in the system is removed with nitrogen to the outside of the system. After the completion of the reaction, unreacted alkylphenol naturally remains, but the residual resin obtained by distilling this off under vacuum or by steam distillation is the alkylphenol aralkyl resin composition of the present invention. Is.

The content of the repeating unit n = 0 of the alkylphenol aralkyl resin composition obtained in such a range of the molar ratio of the alkylphenol (4 molar ratio or more) is actually 50.
It is about 90 mol%. More specifically, when the molar ratio of phenol is 5, the content of n = 0 is about 55 mol%,
In the case of 10, the content of n = 0 is about 65 to 75 mol%, and in the case of 20, the content of n = 0 is about 80 to 90 mol%.

In this reaction, in the α, α′-dialkoxy-p-xylene, the alkyl group R ² has 4 carbon atoms.
When it is below, the reaction tends to be fast, and in the case of a butyl group having 4 carbon atoms, the reaction of the tert-butyl group tends to be slow. Therefore, for use in the present invention, α, α'-dimethoxy-p-xylene, α,
α'-diethoxy-p-xylene, α, α'-di-n-
Propoxy-p-xylene, α, α'-isopropoxy-p-xylene, α, α'-di-p-butoxy-p-xylene, α, α'-di-sec-butoxy-p-xylene, α, Examples thereof include α′-diisobutyl-p-xylene, but are not limited thereto.

Further, the alkylphenol represented by the general formula (c) used in the present invention includes, for example, o-cresol, m-cresol, p-cresol, o-ethylphenol, p-ethylphenol, mixed cresol, p-cresol.
n-propylphenol, o-isopropylphenol, p-isopropylphenol, mixed isopropylphenol, o-sec-butylphenol, m-tert-butylphenol, p-tert-butylphenol, pentylphenol, p-octylphenol, p-nonylphenol, 2, 3-dimethylphenol, 2,4-dimethylphenol, 2,6-dimethylphenol, 3,4-dimethylphenol, 2,4-di-s-butylphenol, 3,5-dimethylphenol, 2,6-di-s -Butylphenol, 2,6
-Di-t-butylphenol, 3-methyl-4-isopropylphenol, 3-methyl-5-isopropylphenol, 3-methyl-6-isopropylphenol, 2
-T-butyl-4-methylphenol, 3-methyl-6
Examples thereof include -t-butylphenol and 2-t-butyl-4-ethylphenol.

The reaction temperature must be 110 ° C or higher, and if it is lower than 110 ° C, the reaction becomes extremely slow. Further, in order to shorten the reaction time as much as possible, a temperature range of about 130 to 240 ° C is desirable. The reaction time is 1 to 20 hours.

The acid catalyst may be an inorganic or organic acid, especially a mineral acid such as hydrochloric acid, phosphoric acid, sulfuric acid or formic acid, or a Friedel-Crafts catalyst such as zinc chloride, aluminum chloride, stannic chloride or ferric chloride. The catalyst may be used alone or in combination with an organic sulfonic acid such as methane sulfonic acid or p-toluene sulfonic acid. The amount of catalyst used is
It is about 0.01 to 5% by weight of the total weight of the alkylphenol, α, α'-dialkoxy-p-xylene.

〔Example〕

 Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1 α, α′-dimethoxy-p was placed in a reaction vessel equipped with a stirrer, a thermometer, and a Dean Stark azeotropic distillation trap.
-Xylene 132.8g (0.8mol), o-cresol 868g
(8.0 mol) and 5 g of paratoluenesulfonic acid were charged, and the mixture was stirred while keeping the mixed solution at 130 to 150 ° C. During the reaction, generated methanol was sequentially removed from the system through the trap.

After 3 hours, the generation of methanol disappeared and the condensation was completed. Then, unreacted o-cresol was distilled off under reduced pressure to obtain 234 g of an alkylphenol aralkyl resin composition having the structure of the general formula (a).

The composition of the obtained resin was measured by high performance liquid chromatography. As a result, n = 0 was 77.3, n = 1 was 18.7, and n = 2.
Was 3.5 (mol%). The softening point of this resin (according to JIS, K-2548) was 32 ° C.

 The result of IR analysis of this resin is shown in FIG.

Example 2 α, α′-dimethoxy-p was placed in a reaction vessel equipped with a stirrer, a thermometer, and a Dean Stark azeotropic distillation trap.
-140 g of xylene (0.84 mol), 910 g of mixed cresol (8.
4 mol), and 5 g of paratoluenesulfonic acid are charged,
Stirring was performed while maintaining the mixed solution at 130 to 150 ° C.
During the reaction, generated methanol was sequentially removed from the system through the trap.

After 3 hours, the generation of methanol disappeared and the condensation was completed. Then, the unreacted mixed cresol was distilled off under reduced pressure to obtain 245 g of an alkylphenol aralkyl resin composition having the structure of the general formula (a).

The composition of the obtained resin was measured by high performance liquid chromatography. As a result, n = 0 was 74.8, n = 1 was 19.1, and n = 2.
Was 4.6 and n ≧ 3 was 1.5 (mol%). Also,
The softening point (according to JIS, K-2548) of this resin was 56 ° C.

 The result of IR analysis of this resin is shown in FIG.

Example 3 α, α′-dimethoxy-p was placed in a reaction vessel equipped with a stirrer, a thermometer, and a Dean-Stark azeotropic distillation trap.
-Xylene 166 g (1 mol), 2,6-dimethylphenol 7
32 g (6 mol) and 6 g of paratoluenesulfonic acid were charged, and the mixture was stirred while keeping the mixed solution at 130 to 150 ° C. During the reaction, generated methanol was sequentially removed from the system through the trap.

After 3 hours, the generation of methanol disappeared and the condensation was completed. Then, unreacted 2,6-dimethylphenol was distilled off under reduced pressure to obtain 317 g of an alkylphenol aralkyl resin composition having the structure of the general formula (a).

The composition of the obtained resin was measured by high performance liquid chromatography. As a result, n = 0 was 62.3, n = 1 was 25.0, and n = 2.
Was 8.6 and n ≧ 3 was 4.1 (mol%). Also,
The softening point (according to JIS, K-2548) of this resin was 49 ° C.

 The result of IR analysis of this resin is shown in FIG.

Comparative Example 1 α, α'-dimethoxy-p was placed in a reaction vessel equipped with a stirrer, a thermometer, and a Dean Stark azeotropic distillation trap.
-250 g (1.5 mol) of xylene, 847 g (9 mol) of phenol, and 1.1 g of p-toluenesulfonic acid were charged, and the mixed solution was stirred while keeping at 130 to 150 ° C. During the reaction, generated methanol was sequentially removed from the system through the trap.

After 2 hours, the generation of methanol disappeared and the condensation was completed. Then, unreacted phenol was distilled off under reduced pressure to obtain 393 g of a phenol aralkyl resin composition having the structure of the general formula (a).

The composition of the obtained resin was measured by high performance liquid chromatography. As a result, n = 0 was 60.3, n = 1 was 24.3, and n = 2.
Was 9.2, n = 3 was 3.8, and n ≧ 4 was 2.4 (mol%). The softening point of this resin (according to JIS, K-2548) was 45 ° C.

Example 4 205 g of the alkylphenol aralkyl resin composition obtained in Example 1 and 730 g (7.9 mol) of epichlorohydrin were mixed and charged into a reaction vessel equipped with a stirrer, a Dean Stark azeotropic distillation trap and a dropping funnel.

The temperature of this mixture was raised to 115 to 119 ° C with stirring, 195 g of 40% sodium hydroxide aqueous solution was added dropwise at the same temperature for 4 hours, the distilled water was continuously separated and recovered, and the phase of epichlorohydrin was placed in a reactor. I brought it back. After completion of dropping, the reaction is completed by removing distilled water.

After that, excess epichlorohydrin was distilled under reduced pressure, the reaction product was dissolved in 500 g of methyl isobutyl ketone (MIBK), sodium chloride and a slight excess of sodium hydroxide were filtered off, and the solvent was distilled off under reduced pressure to give a brown powder. 249 g of the epoxy resin of was obtained.

The epoxy equivalent of the resin was 230 g / eq, and the viscosity (by E-type viscometer manufactured by Tokyo Keiki Co., Ltd.) was 172 g / cm · sec (35 ° C.).

Example 5 130 g of the alkylphenol aralkyl resin composition obtained in Example 2 and 500 g (5.4 mol) of epichlorohydrin were mixed and charged into a reaction vessel equipped with a stirrer, a Dean Stark azeotropic distillation trap and a dropping funnel.

The temperature of this mixture was raised to 115 to 119 ° C with stirring, then 230 g of 40% aqueous sodium hydroxide solution was added dropwise at the same temperature over 4 hours, the distilled water was continuously separated and recovered, and the phase of epichlorohydrin was placed in the reactor. Returned to. After completion of dropping, the reaction is completed by removing distilled water.

After this, excess epichlorohydrin was distilled under reduced pressure, the reaction product was dissolved in 350 g of methyl isobutyl ketone (MIBK), sodium chloride and a slight excess of sodium hydroxide were filtered off, the solvent was distilled off under reduced pressure, and the brown 167 g of the epoxy resin of was obtained.

The epoxy equivalent of the resin was 236 g / eq, and the viscosity (by E-type viscometer manufactured by Tokyo Keiki Co., Ltd.) was 651 g / cm · sec (35 ° C.).

Example 6 200 g of the alkylphenol aralkyl resin composition obtained in Example 3 and 530 g (5.7 mol) of epichlorohydrin were mixed and charged into a reaction vessel equipped with a stirrer, a Dean Stark azeotropic distillation trap and a dropping funnel.

The temperature of this mixture was raised to 115 to 119 ° C. with stirring, then 135 g of 40% sodium hydroxide aqueous solution was added dropwise at the same temperature over 4 hours, the distilled water was continuously separated and recovered, and the phase of epichlorohydrin was placed in the reactor. Returned to. After completion of dropping, the reaction is completed by removing distilled water.

After that, excess epichlorohydrin was distilled under reduced pressure, the reaction product was dissolved in 500 g of methyl isobutyl ketone (MIBK), sodium chloride and a slight excess of sodium hydroxide were filtered off, and the solvent was distilled off under reduced pressure to give a brown powder. 242 g of the epoxy resin of was obtained.

The epoxy equivalent of the resin was 243 g / eq, and the viscosity (by E-type viscometer manufactured by Tokyo Keiki Co., Ltd.) was 879 g / cm · sec (35 ° C.).

Comparative Example 2 Phenol aralkyl resin composition obtained in Comparative Example 1
393 g and epichlorohydrin 1100 g (11.9 mol) were mixed and charged into a reaction vessel equipped with a stirrer, a Dean Stark azeotropic distillation trap and a dropping funnel.

The temperature of this mixture was raised to 115 to 119 ° C with stirring, 275 g of 40% aqueous sodium hydroxide solution was added dropwise at the same temperature over 4 hours, the distilled water was continuously separated and recovered, and the phase of epichlorohydrin was placed in the reactor. Returned to. After completion of dropping, the reaction is completed by removing distilled water.

After this, excess epichlorohydrin was distilled under reduced pressure, the reaction product was dissolved in 1500 g of methyl isobutyl ketone (MIBK), sodium chloride and a small excess of sodium hydroxide were filtered off, and the solvent was distilled off under reduced pressure to give a yellow 465 g of an oily epoxy resin was obtained.

The epoxy equivalent of the resin was 227 g / eq, and the viscosity (by E-type viscometer manufactured by Tokyo Keiki Co., Ltd.) was 468 g / cm · sec (35 ° C.).

Use Example 1 As a curing agent for an epoxy resin (trade name: Epicoat 828, manufactured by Shell Chemical Co., Ltd.), the alkylphenol aralkyl resin composition obtained in Examples 1 to 3, the phenol aralkyl resin obtained in Comparative Example 1, and a phenol novolac. Using resin (BRG # 5853, Showa High Polymer Co., Ltd.),
2,4,6-Tris (dimethylaminomethyl) as accelerator
Phenol (TAP) was used and blended under the conditions shown in Table-1. The mixture was cast, and the mechanical properties of the cured resin after processing were measured.

The results are shown in Table-1. In addition, the results of those using the alkylphenol aralkyl resin composition obtained in Examples 1 to 3 as curing agents are shown as Examples 1 to 3, respectively, and the results of those using the phenol aralkyl resin composition obtained in Comparative Example 1 are shown. Comparative Experiment Example 1 is shown, and the result of using a phenol novolac resin (BRG # 5853, Showa Highpolymer Co., Ltd.) is shown as Comparative Experiment Example 2.

USE EXAMPLE 2 Each of the epoxy resins obtained in Examples 4 to 6 and Comparative Example 2 and Epicoat 828 (manufactured by Ciel Chemical Co.) introduced from bisphenol A was used as a liquid MDA (Epicure Z; manufactured by Ciel Chemical Co.) as a curing agent. ) Was blended under the conditions shown in Table 2, and each of the mixtures was cast, and the mechanical properties of the cured resin after the processing were measured.

The results are shown in Table-2. The results of the epoxy resins obtained in Examples 4 to 6 are shown as Experimental Examples 4 to 6, respectively, and the results of the epoxy resin obtained in Comparative Example 2 are shown as Comparative Experimental Example 3, Epicoat 828 (produced by Shell Chemical Co., Ltd.). The results are shown as Comparative Experimental Example 4.

[Effects of the Invention] As described above, the alkylphenol aralkyl resin composition of the present invention is produced by a simple method.
Further, the epoxy resin using this alkylphenol aralkyl resin composition as a raw material has a low molecular weight and is excellent in workability because it is liquid or has a low melting point at room temperature, and its cured product and this alkylphenol aralkyl resin composition are used as ordinary epoxy resins. A cured product when used as a curing agent for a resin has excellent water resistance and oxidation resistance, and in particular, the tensile strength and elongation are greatly improved. Further, it has sufficient heat resistance.

The alkylphenol aralkyl resin composition of the present invention having the above-mentioned advantages can be expected to be applied to various applications, and particularly, it is expected to be applied to the electronic material field where such performance has been conventionally demanded.

[Brief description of drawings]

1 to 3 are diagrams showing IR analysis results of the phenol aralkyl resins obtained in Examples 1 to 3.

Claims (2)

[Claims] 1. A compound of the general formula (a) (However, in the formula, R ¹ represents hydrogen or an alkyl group having 1 to 9 carbon atoms, R ² represents an alkyl group having 1 to 9 carbon atoms,
n represents an integer of 0 to 5 and contains n = 0 in an amount of 50 mol% or more. ) An alkylphenol aralkyl resin composition represented by: 2. Formula (b) (However, R ³ in the formula represents a lower alkyl group having 4 or less carbon atoms.) In the α, α′-dialkoxy-p-xylene represented by the general formula (c) (However, R ¹ in the formula represents hydrogen or an alkyl group having 1 to 9 carbon atoms, and R ² represents an alkyl group having 1 to 9 carbon atoms.) The general formula (a) is characterized in that unreacted alkylphenol is separated from the reaction product obtained by (However, in the formula, R ¹ represents hydrogen or an alkyl group having 1 to 9 carbon atoms, R ² represents an alkyl group having 1 to 9 carbon atoms,
n represents an integer of 0 to 5 and contains n = 0 in an amount of 50 mol% or more. ) A method for producing an alkylphenol aralkyl resin composition represented by: