JPH06322095A - Production of aromatic polycarbonate resin - Google Patents

Abstract

PURPOSE:To obtain desirably the subject resin while avoiding problems caused by a conventional catalyst by polymerizing an aromatic dihydroxy compound with a diaryl carbonate by melt polycondensation in the presence of a glass filler as a catalyst. CONSTITUTION:This production method comprises polymerizing an aromatic dihydroxy compound (a) with a diaryl carbonate by melt polycondensation using a glass filler (e.g. chopped glass strand) as a catalyst in an amount of 0.1wt.% or larger based on the compound (a). The method is free from such problems caused by a conventional catalyst as induction and acceleration of a side reaction, necessity for a long polycondensation time, and catalyst inclusion in the resin. Thus, an aromatic polycarbonate resin containing no chlorine atom can be easily produced through melt polycondensation. By regulating the amount of the filler, this resin can be obtained directly as a filled resin having a desired glass filler loading.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing an aromatic polycarbonate resin. More specifically, it relates to a method for producing an aromatic polycarbonate resin in which an aromatic dihydroxy compound and a diaryl carbonate are subjected to a melt polycondensation reaction in the presence of a glass-based filler as a catalyst.

[0002]

2. Description of the Related Art Aromatic polycarbonate resins are transparent,
It is an engineering plastic having excellent properties such as impact resistance and heat resistance, and is a thermoplastic resin having a very high utility value. Aromatic polycarbonate resins are mainly produced by the phosgene method in which an alkaline aqueous solution of an aromatic dihydroxy compound is reacted with phosgene in the presence of an organic solvent, or by melting an aromatic dihydroxy compound and a diaryl carbonate in the presence of an ester exchange catalyst under high temperature and high vacuum. It is produced by a transesterification method of causing a condensation reaction.

The transesterification method is a process that requires a transesterification catalyst and high temperature and high vacuum, but it is more economical than the phosgene method, and aromatic polycarbonate resin containing substantially no chlorine atom is used. There are advantages to be obtained. Against this background, various proposals have recently been made regarding a method for producing an aromatic polycarbonate resin by a transesterification method. However, all of these proposals use some transesterification catalyst.

Conventionally, a basic compound has been generally used as a transesterification catalyst, and in addition, a special quaternary ammonium compound, a phosphonium compound, a special organic acidic compound and the like have been used. However, basic compounds are known to induce and promote side reactions during melt polycondensation. Further, in the case of a special compound, the polycondensation reaction requires a longer time than the basic catalyst, is difficult to handle, and is very expensive, which is often industrially disadvantageous. Further, the transesterification catalyst remains in the aromatic polycarbonate resin obtained by melt polycondensation, which has an unfavorable effect such as a factor causing deterioration of physical properties. For this reason, it is desirable to remove the transesterification catalyst from the product aromatic polycarbonate resin, but it is impossible to remove the catalyst from the aromatic polycarbonate resin obtained by melt polycondensation. It has stopped changing.

On the other hand, it has been attempted to improve the dimensional accuracy, rigidity, heat resistance, etc. by blending a glass-based filler with an aromatic polycarbonate resin, and it is widely used as a substitute material for metals. In the aromatic polycarbonate resin composition containing such a filler, a method is generally used in which a filler is mixed and kneaded when the aromatic polycarbonate resin is heated and melted by an extruder or the like to be pelletized.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for transesterifying an aromatic polycarbonate resin which does not cause a problem with the above catalyst.

The present inventor has noticed that the aromatic polycarbonate resin obtained by the transesterification method is already in a molten state and that a glass-based filler can be added and added at the production stage, and the glass by the transesterification method is used. As a result of various studies on the production of an aromatic polycarbonate resin containing a system filler, when a polycondensation reaction of an aromatic dihydroxy compound and a diaryl carbonate in the presence of a glass system filler is carried out, a commonly used transesterification catalyst is added. It was found that a high-molecular-weight glass-filled aromatic polycarbonate resin can be obtained without any problem, and further intensive studies were conducted on the catalytic ability of the glass-filler, resulting in completion of the present invention.

[0008]

Means for Solving the Problem In the present invention, when a polycondensation reaction of an aromatic dihydroxy compound and a diaryl carbonate is carried out to produce an aromatic polycarbonate resin, a glass-based filler as a catalyst is added to the aromatic dihydroxy compound. The method for producing an aromatic polycarbonate resin is characterized by using 0.1% by weight or more.

The aromatic dihydroxy compound used in the present invention may be any aromatic dihydroxy compound used as a raw material for an aromatic polycarbonate resin, such as bis (4-hydroxyphenyl) methane or 1,1-bis (4).
-Hydroxyphenyl) ethane, 2,2- (4-hydroxyphenyl) propane [commonly known as bisphenol A],
2,2-bis (4-hydroxyphenyl) butane, 2,
2-bis (4-hydroxyphenyl) octane, 1,1
-Bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxy-3-te)
Bis (hydroxyaryl) alkanes such as rt-butylphenyl) propane and 2,2-bis (4-hydroxy-3-bromophenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1 -Bis (4
-Hydroxyphenyl) cyclohexane and other bis (hydroxyaryl) cycloalkanes, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-
Dihydroxy diaryl ethers such as 3,3′-dimethyldiphenyl ether, 4,4′-dihydroxydiphenyl sulfide, 4,4′-dihydroxy-3,3 ′
-Dihydroxydiaryl sulfides such as dimethyldiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfoxide, 4,4'-dihydroxy-3,3'-
Examples thereof include dihydroxydiaryl sulfoxides such as dimethyldiphenyl sulfoxide, and dihydroxydiaryl sulfones such as 4,4′-dihydroxydiphenylsulfone and 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfone. Among them, bisphenol A
Is preferred.

As the diaryl carbonate,
For example, diphenyl carbonate, ditolyl carbonate, bis (chlorophenyl) carbonate, dinaphthyl carbonate, bis (diphenyl) carbonate, dimethyl carbonate, diethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate and the like can be mentioned. Of these, diphenyl carbonate is preferred.

The glass filler used as a catalyst in the present invention may have any shape, for example, glass balloon, glass flake, glass powder, glass filament, glass strand, glass yarn, glass roving, glass chopped strand, milled glass fiber. , Glass roving cloth, glass cloth, glass mat and the like. The glass composition may be either alkali glass or non-alkali glass, but alkali glass is particularly preferable.

The glass filler is added in an amount of 0.1% by weight or more based on the aromatic dihydroxy compound. If the amount of the glass-based filler added is less than 0.1% by weight, the rate of the polycondensation reaction will be slow and it will be necessary to allow the resin to stay at a high temperature for a long time, which will adversely affect the physical properties and hue of the aromatic polycarbonate resin obtained. Like The upper limit of the amount added is not particularly limited, and may be determined depending on the physical properties required for the obtained glass-filler-containing aromatic polycarbonate resin composition.

Further, the apparatus for producing the glass-filled aromatic polycarbonate resin of the present invention includes:
There is no particular problem as long as it is an apparatus that can be used for melt polymerization. For example, a tank reactor, a thin film evaporation reactor, a horizontal reactor and the like can be mentioned. The reaction can be carried out batchwise or continuously.

Further, if necessary, additives such as an ultraviolet absorber, an antioxidant, an antistatic agent, a release agent, a dye, a pigment, a natural oil, a synthetic oil, an antifogging agent, a wax, an organic filler, You may add additives, such as an inorganic type filler. These additives are preferably added at the end of polymerization, but they can be added at other stages if necessary. For example, an aromatic polycarbonate resin composition having excellent light diffusivity can be obtained by adding calcium carbonate powder at any stage, and an aromatic polycarbonate resin having high light reflectance can be obtained by adding titanium oxide at any stage. It has an advantage that the merit of producing an aromatic polycarbonate resin in the transesterification method such as obtaining a composition can be fully utilized. Further, the catalyst used in the transesterification method may be used in combination as long as the amount is small enough not to deviate from the object of the present invention.

[0015]

EXAMPLES The present invention will be further described with reference to the following examples. The parts in the examples are parts by weight.

[0016]

Example 1 150 parts of bisphenol A, 147.8 parts of diphenyl carbonate and 10 parts of chopped strands of C glass were charged into a tank-type reaction tank and heated to 150 ° C. to melt. At the same temperature, the pressure inside the tank was reduced to 100 mmHg to start the polycondensation reaction. After 3 hours, 240 ° C. and 20 mmHg were reached to complete the precondensation reaction. Then, the pressure in the tank was returned to normal pressure with nitrogen gas, and the temperature was raised to 300 ° C.
The condensation reaction was carried out at a vacuum degree of Hg for 2 hours and then at a vacuum degree of 0.3 mmHg for 5 hours. The viscosity average molecular weight measured by removing the glass chopped strands from the obtained aromatic polycarbonate resin containing glass chopped strands was 18
It was 900. The hue of the aromatic polycarbonate resin containing glass chopped strands was very good.

[0017]

Example 2 A polycondensation reaction was carried out in the same manner as in Example 1 except that the charged amount of chopped strands of C glass was 30 parts. The viscosity average molecular weight measured by removing the glass chopped strands from the obtained aromatic polycarbonate resin containing glass chopped strands was 23600. The hue of the aromatic polycarbonate resin containing glass chopped strands was very good.

[0018]

EFFECTS OF THE INVENTION According to the present invention, an aromatic polycarbonate resin containing substantially no chlorine atom can be easily produced by a melt polycondensation reaction without any problems caused by conventional catalysts, and is used as a catalyst. The desired glass-filler-containing aromatic polycarbonate resin composition can be produced by melt-polycondensation reaction at once by adjusting the amount of the glass-filler. .

Claims (1)

[Claims] 1. A glass-based filler is used as a catalyst in an amount of 0.1% by weight or more based on the aromatic dihydroxy compound in the production of an aromatic polycarbonate resin by melt polycondensation reaction of an aromatic dihydroxy compound and a diaryl carbonate. A method for producing an aromatic polycarbonate resin, comprising: