JP2002020463A - Production method of phenolaralkyl resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an easily producing method of a phenolaralkyl resin having excellent heat stability with time using inexpensive raw materials. SOLUTION: The production method of a phenolaralkyl resin comprises reacting an aromatic bishalogeno methyl compound with a phenolic compound, and then adding a specific buffering agent in a step of recovering the unreacted phenolic compound.

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 low cost and excellent workability.

[0002]

2. Description of the Related Art Phenol aralkyl resin is a compound useful as a semiconductor encapsulant epoxy resin curing agent, epoxy resin raw material, adhesive, molding material, and paint. The cured product has excellent electrical properties and heat resistance. Due to its adhesiveness, moisture resistance (water resistance), etc., it is widely used in the fields of electric / electronic parts, structural materials, adhesives, paints and the like.

[0003] The phenol aralkyl resin is usually represented by the following formula (1) R- (CH ₂ X) ₂ (1) (where R is a phenylene group, an alkyl-substituted phenylene group, a biphenylene group, a divalent diphenyl ether residue,
Or X represents a naphthylene group, and X represents a halogen atom. )) Or an aromatic bishalogenomethyl compound represented by the following formula (2): R- (CH ₂ OR ') ₂ (2) (wherein R is a phenylene group, an alkyl-substituted phenylene group, a biphenylene group, a divalent diphenyl ether residue) Group,
Or, it represents a naphthylene group, and R ′ represents a lower alkyl group. )) And a phenol compound. However, the method of using an aromatic bishalogenomethyl compound is to remove the hydrogen halide gas generated during the reaction out of the system by passing an inert gas such as nitrogen gas, or to remove the hydrogen halide gas under reduced pressure. However, before the resin is sufficiently removed, if the resin produced to recover unreacted phenolic compounds is exposed to high temperatures, the resin will have a high molecular weight due to the effect of hydrogen halide remaining in the reaction system. And there is a quality problem that the melt viscosity increases. This problem is significant because the larger the reaction scale, the longer it takes to recover the phenol compound. If a residual hydrogen halide or acid catalyst is used, it is possible to address this problem by neutralizing the acid catalyst, but since the reaction system is not usually a system containing water, the residual hydrogen halide Neutralization with an alkali such as caustic soda has problems that it is difficult to determine the pH end point and that a complicated operation of adding a neutralizing agent while confirming the end point is required. On the other hand, a method using an aromatic bisalkoxymethyl compound that does not generate hydrogen halide is disadvantageous in cost because an expensive bisalkoxymethyl compound is used as a raw material.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a phenol aralkyl resin which can be easily neutralized using an inexpensive aromatic bishalogenomethyl compound. .

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. As a result, after reacting an aromatic bishalogenomethyl compound with a phenol compound, the present inventors have specified a process for recovering an unreacted phenol compound. By adding a buffering agent, it was possible to prevent the phenol aralkyl resin from having a high molecular weight at a high temperature, and to obtain a phenol aralkyl resin having a stable quality.
The present invention has been reached.

That is, the present invention relates to (1) a compound represented by the general formula (1) R- (CH ₂ X) ₂ (1) (wherein R is a phenylene group, an alkyl-substituted phenylene group, a biphenylene group, a divalent diphenyl ether residue) Group,
Or a naphthylene group, and X represents a halogen atom)
A method for producing a phenol aralkyl resin, comprising reacting an aromatic bishalogenomethyl compound and a phenol compound represented by the formula: and then collecting an unreacted phenol compound after adding a buffer having a pH of 4 to 9, (2)
The present invention relates to the method for producing a phenol aralkyl resin according to the above (1), wherein the buffer is an inorganic compound, and (3) the method for producing a phenol aralkyl resin according to the above (1), wherein the buffer is a phosphate.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An aromatic bishalogenomethyl compound as a raw material used in the production method of the present invention is represented by the formula (1). R in the formula (1) is a phenylene group,
An alkyl-substituted phenylene group, a biphenylene group, a divalent diphenyl ether residue, or a naphthylene group, specifically, the following formula

[0008]

Embedded image

And the like. X represents a halogen atom such as fluorine, chlorine, bromine or iodine.

Specific examples of the aromatic bishalogenomethyl compound that can be used include 1,2-di (chloromethyl) benzene, 1,2-di (bromomethyl) benzene, 1,3-di (chloromethyl) benzene, 1,3-di (bromomethyl) benzene, 1,3-di (fluoromethyl) benzene, 1,4-di (chloromethyl) benzene, 1,4-di (bromomethyl) benzene, 1,4-di (fluoromethyl) Benzene, 1,4-di (chloromethyl) -2,5-
Dimethylbenzene, 1,3-di (chloromethyl) -4,
6-dimethylbenzene, 1,3-di (chloromethyl)-
2,4-dimethylbenzene, 4,4′-bis (chloromethyl) -1,1′-biphenyl, 4,4′-bis (bromomethyl) -1,1′-biphenyl, 2,4′-bis (chloro Methyl) -1,1′-biphenyl, 2,4′-
Bis (bromomethyl) -1,1′-biphenyl, 2,
2′-bis (chloromethyl) -1,1′-biphenyl,
2,2′-bis (bromomethyl) -1,1′-biphenyl, 4,4′-bis (chloromethyl) diphenyl ether, 2,7′-bis (chloromethyl) naphthalene, and the like. Of these, compounds in which X is chlorine are preferred industrially.

Specific examples of phenol compounds that can be used include phenol, p-cresol, o-cresol, m
-Cresol, p-ethylphenol, o-ethylphenol, p-isopropylphenol, pn-propylphenol, p-sec-butylphenol, o-
sec-butylphenol, p-tert-butylphenol, o-tert-butylphenol, p-ter
t-amylphenol, p-tert-octylphenol, nonylphenol, dodecylphenol, p-cyclohexylphenol, o-phenylphenol, p
-Phenylphenol, p-cumylphenol, p-chlorophenol, o-chlorophenol, p-bromophenol, o-bromophenol, α-naphthol, β
-Naphthol, resorcin, catechol, hydroquinone, pyrogallol, phloroglucinol, p-aminophenol, m-aminophenol, 2,2-bis (4-
Examples thereof include (hydroxyphenyl) propane, bis (hydroxyphenyl) methane, and 4,4′-thiodiphenol, but are not limited thereto as long as they have a phenolic hydroxyl group. In the present invention, phenol, p-cresol, o-cresol or m-
Cresol is preferred. These phenol compounds can be used alone or in combination of two or more.

The amount of the phenol compound to be used relative to the compound of the formula (1) is usually 1.
It is 0 to 10 mol, preferably 1.2 to 5.0 mol.

In the production method of the present invention, an acid catalyst is used if necessary. Various acids can be used as the acid catalyst, and examples thereof include organic or inorganic acids such as sulfuric acid, p-toluenesulfonic acid, and oxalic acid, and Friedel-Crafts type catalysts such as stannic chloride, zinc chloride, and ferric chloride. Can be Among them, stannic chloride, sulfuric acid and p-toluenesulfonic acid are preferred.
The amount of these acid catalysts varies depending on the type of the catalyst, but may be added in the range of 0.0005 to 1% by weight based on the compound of the formula (1).

[0014] The reaction temperature is usually 40 to 200 ° C, preferably 50 to 150 ° C. The reaction time is 0.5 to 20 hours, preferably 1 to 15 hours. The reaction may be carried out while all the raw materials are charged at once and the temperature is raised, or may be carried out by sequentially adding an aromatic bishalogenomethyl compound while keeping the phenol compound at a constant temperature in advance. The reaction is preferably carried out without a solvent in which the amount of residual hydrogen halide is reduced, but an organic compound which does not directly participate in the reaction, such as toluene, monochlorobenzene, dichlorobenzene, or a lower alcohol, can be used as a solvent.

The hydrogen halide gas generated during the reaction is removed from the system by flowing an inert gas such as nitrogen gas, or is removed under reduced pressure.

In the present invention, a buffer is added after the reaction of the compound of the formula (1) with the phenol compound is completed. The buffer is not particularly limited as long as it has a pH of 4 to 9 and exhibits a buffering action, and examples thereof include a combination of an organic acid salt and an inorganic base, and an inorganic acid salt. However, when an organic acid salt is used, the organic acid generated by the neutralization is at a high temperature,
Since it is expected that the unreacted phenol compound is mixed with the phenol compound and recovered in the step of recovering the unreacted phenol compound under a high vacuum, it is not preferable when the recovered phenol compound is recycled. Specific examples of the inorganic acid salt that can be used include potassium dihydrogen phosphate, disodium hydrogen phosphate, sodium dihydrogen phosphate, sodium tripolyphosphate, and sodium borate. Phosphates such as disodium, sodium dihydrogen phosphate and sodium tripolyphosphate are preferred. The buffer may be added as an aqueous solution or as a powder. The addition amount depends on the amount of hydrogen halide remaining in the reaction mixture and the amount of the acid catalyst used, but is usually 0.1 to 10% for the compound of the formula (1).
5 to 10% by weight. The operation of adding the buffer does not require a complicated operation such as adding a neutralizing agent while checking the pH, and the operation is excellent because the buffer may be added all at once.

The desired phenol aralkyl resin can be obtained by recovering the unreacted phenol compound and the solvent after adding the buffer. The unreacted phenol compound is preferably recovered by distillation under normal pressure or reduced pressure. It is also possible to blow in steam and distill off by steam distillation. The temperature for distillation and recovery of the phenol compound is usually 100 to 180 ° C, and the degree of reduced pressure is usually 0.1 to 25 kPa.
It is about.

[0018]

EXAMPLES Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. The softening point and melt viscosity in the examples were measured under the following conditions. -Softening point: Measured by a method according to JIS K-7234-Melt viscosity: Melt viscosity in cone plate method at 150 ° C Measurement machine: Cone plate (ICI) high temperature viscometer (RESE)
ACH EQUIPMENT (LONDON) LTD.)

Example 1 A four-necked flask equipped with a stirrer, a thermometer and a condenser was charged with 164.7 parts by weight of phenol and stirred at 50 ° C. with 4,4′-bis (chloromethyl) -1,1. '-
141.9 parts by weight of biphenyl were added. 0.05 parts by weight of p-toluenesulfonic acid monohydrate was added thereto, and the mixture was reacted at normal pressure at 53 to 56 ° C. for 1.5 hours and at 68 to 72 ° C. for 1 hour, and then at 98.7 to 100 kPa. 7 under reduced pressure
The reaction was performed at 8-82 ° C for 1 hour. After the reaction solution was cooled to 70 ° C., 4.0 parts by weight of sodium tripolyphosphate was added and stirred for 0.5 hour. Next, unreacted phenol in the system is reduced to 140 to 150 ° C. under a reduced pressure of 0.6 to 1.3 kPa.
Was collected. As a result, 182.2 parts by weight of a phenol aralkyl resin (P1) was obtained. The melt viscosity of the obtained phenol aralkyl resin (P1) is 0.12 Pa · s,
The softening point was 106 ° C.

Comparative Example 1 164.7 parts by weight of phenol was charged into a four-necked flask equipped with a stirrer, a thermometer and a condenser.
4,4'-bis (chloromethyl)-
141.9 parts by weight of 1,1'-biphenyl was added and the temperature was gradually raised. 1.5-hour at 53-56 ° C under normal pressure, 68-72
C. for 1 hour, then 98.7-100 kPa
The reaction was carried out at 78 to 82 ° C. for 1 hour under reduced pressure. Next, unreacted phenol in the system was recovered at 140 to 150 ° C. under a reduced pressure of 0.6 to 1.3 kPa. As a result, 175.
5 parts by weight of a phenol aralkyl resin (P2) was obtained.
The obtained phenol aralkyl resin (P2) had a melt viscosity of 0.12 Pa · s and a softening point of 110 ° C.

Test Example Each of the phenol aralkyl resins obtained in Example 1 and Comparative Example 1 was subjected to a reduced pressure of 0.6 to 1.3 kPa under reduced pressure.
It was kept at 145 ° C. for 10 hours, and the melt viscosity was measured. The result is shown in FIG.

From FIG. 1, it is clear that the phenol aralkyl resin obtained by the production method of the present invention has excellent stability over time when heated.

[0023]

According to the production method of the present invention, it is possible to easily produce a phenol aralkyl resin excellent in stability over time during heating using inexpensive raw materials.

[Brief description of the drawings]

FIG. 1 shows a change in viscosity of a phenol aralkyl resin obtained in Example 1 and Comparative Example 1 when heated. The horizontal axis shows the elapsed time and the vertical axis shows the melt viscosity.

Claims (3)

[Claims] A compound of the general formula (1) R- (CH ₂ X) ₂ (1) wherein R is a phenylene group, an alkyl-substituted phenylene group, a biphenylene group, a divalent diphenyl ether residue,
Or X represents a naphthylene group, and X represents a halogen atom. A method for producing a phenol aralkyl resin, comprising reacting an aromatic bishalogenomethyl compound represented by the formula (1) with a phenol compound, adding a buffer having a pH of 4 to 9, and recovering the unreacted phenol compound. . 2. The method for producing a phenol aralkyl resin according to claim 1, wherein the buffer is an inorganic compound. 3. The method according to claim 1, wherein the buffer is a phosphate.