JP2564565B2 - Method for producing polycarbonate resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a polycarbonate resin having improved fluidity and mold releasability, and more specifically, to a specific monofunctional phenol as a terminal terminating agent. The present invention relates to a method for producing a polycarbonate resin, which is excellent as a molding material or a film.

[Conventional technology]

Conventional polycarbonate resin has heat resistance, mechanical strength,
It is known as an engineering plastic with excellent dimensional stability and is widely used as parts for automobiles, electric / electronics, sundries, etc.

By the way, since the polycarbonate resin has a high melt viscosity, it is necessary to perform molding at a high temperature of 280 ° C to 380 ° C or to lower the molecular weight of the resin in order to secure sufficient fluidity in order to obtain a molded product by injection molding. Measures have been taken.

However, in molding at high temperature, thermal decomposition of the polycarbonate resin is unavoidable, and the color tone of the resin is deteriorated, and the molecular weight is also reduced, which causes problems such as poor appearance and insufficient strength of the resulting molded product. Further, when the molecular weight of the resin is lowered, various problems are often caused in terms of strength.
Therefore, it has been a problem to be solved in the art to improve the fluidity of the resin and make an improvement so that the resin can be molded at a relatively low temperature.

Further, although the polycarbonate resin is excellent in dimensional stability, it has a poor releasability from the mold, and therefore, there are problems that residual strain remains in the molded product and it is necessary to extend the molding cycle. In order to solve this, in general, a mold release agent is sprayed on the mold surface or added to the resin, but in some cases the molded product may become turbid or the surface appearance may deteriorate. I was in trouble. Therefore, improving the releasability of the polycarbonate resin without causing these defects has been a problem to be solved in order to improve the moldability and increase the molding cycle.

[Object of the Invention]

As a result of intensive studies to improve the drawbacks of the polycarbonate resin as described above, the present inventors produced a molding material excellent in fluidity and mold releasability by using a polycarbonate resin having a specific terminal group. It has been found that the above problems can be solved, and the problems of the above-mentioned conventional techniques are solved.

That is, the present invention is characterized in that an aromatic polycarbonate resin comprising a bisphenol compound is produced by using a fluorine-containing monofunctional phenol represented by the following general formula (I) as a terminal stopper. The present invention relates to a method for producing a polycarbonate resin.

R ¹ represents an alkyl group having 1 to 6 carbon atoms, an aromatic hydrocarbon group or a halogen atom. l represents an integer of 0 to 4, R ² represents (CF ₂ ) _n X, CH ₂ (CF ₂ ) _n X or CH ₂ CH ₂ (CF ₂ ) _n X. (N is an integer from 0 to 18, X is F when n = 0, and F or H when n is other than 0.) [Constitution of Invention] The present invention will be described in detail below.

The aromatic polycarbonate resin referred to in the present invention is specifically produced by reacting one or more bisphenol compounds with phosgene or a carbonic acid ester such as diphenyl carbonate.

As the bisphenol compound, those represented by the following general formula (III) are used.

General formula (III) The bisphenol compound that can be used in the present invention,
Specifically, bis- (4-hydroxyphenyl) methane, 1,1-bis- (4-hydroxyphenyl) ethane, 1,1-bis- (4-hydroxyphenyl) propane, 2,2-bis- (4 -Hydroxyphenyl) propane (ie, bisphenol A), 2,2-bis- (4-hydroxyphenyl) butane, 2,2-bis- (4-hydroxyphenyl) pentane, 2,2-bis- (4-hydroxyphenyl) ) -3-Methylbutane, 2,2-bis- (4-hydroxyphenyl) hexane, 2,2-bis- (4-hydroxyphenyl) -4-methylpentane, 1,1-bis- (4-hydroxyphenyl) Phenylmethane, 1,1-bis- (4-hydroxyphenyl) cyclopentane, 1,1-bis- (4-hydroxyphenyl) cyclohexane, 2,2-bis- (4-hydroxy-3-chloro) Phenyl) propane, 2,2-bis- (4-hydroxy-3,5-dimethylphenyl) propane, 4,4'-dihydroxydiphenylether, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxydiphenylsulfide, etc. A bisphenol compound can be mentioned.

The polycarbonate produced by the present invention preferably has a viscosity average molecular weight of 9,500 to 100,000. More preferably, it is 10,500-40,000. The term "viscosity average molecular weight" used here means the following formula-1 and formula-2 from η _sp measured at 20 ° C using a 6.0 g / methylene solution of polymer.
It is a value that can be obtained more.

eta _sp / C = [eta] (1 + K'η _sp) 1) [eta] = KM α ²⁾ wherein C: Polymer concentration (g /) [eta]: Intrinsic viscosity K ': 0.28 K: 1.23 × 10 - ⁵ α: 0.83 M: Average molecular weight That is, if it is less than 9,500, it is not preferable in terms of mechanical properties, and if it exceeds 100,000, the fluidity is poor and there is a problem in obtaining a molded product with small strain.

Usually, at the time of producing a polycarbonate resin, the molecular weight is controlled by using one or more monofunctional phenol compounds as a terminal stopper, but in the present invention, a phenol compound represented by the following general formula (I) is used.

R ¹ is an alkyl group having 1 to 6 carbon atoms, an aromatic hydrocarbon group,
Or represents a halogen atom. l represents an integer of 0 to 4, R ² represents (CF ₂ ) _n X, CH ₂ (CF ₂ ) _n X or CH ₂ CH ₂ (CF ₂ ) _n X.

(N is an integer from 0 to 18, X is F when n = 0, and is F or H at other times.) Fluorine-containing compound represented by the general formula (I) which can be used in the present invention. Examples of the monofunctional phenol compound include a compound in which a fluorinated alkyl group-containing alcohol is subjected to a transesterification reaction with an ester compound represented by the general formula (IV) to form a phenol at the terminal.

R ¹ is an alkyl group having 1 to 6 carbon atoms, an aromatic hydrocarbon group,
Or a halogen atom, l is an integer of 0 to 4, R ⁵ is 1 carbon atom
Represents an alkyl group or aromatic hydrocarbon group of 6;

Specific examples of the fluorinated alkyl group-containing alcohol include 2,2,2-trifluoroethanol, 1H, 1H-pentafluoropropanol, 1H, 1H-perfluoro-1-butanol, 1H, 1H-perfluoro-1- Heptanol, 1H, 1H-perfluoro-1-octanol, 1H, 1H, 5H-octafluoro-1-pentanol, 1H, 1H, 7H-perfluoro-1-heptanol, 1H, 1H, 9H-perfluorononanol -1, 1H, 1H, 2H, 2H-perfluorohexan-1-ol, 1H, 1H, 2H, 2H-perfluorooctane-1-ol, 1H, 1H, 2H, 2H-perfluorodecane-1-ol , 1H, 1H, 2H, 2H-perfluorododecane-1-ol, 1H, 1H, 2H, 2H-perfluorotetradecane-1-ol, and the like. These alcohol-terminated compounds are easily produced by, for example, performing a transesterification reaction of a fluorinated alkyl group-containing alcohol with an alkyl ester of parahydroxybenzoic acid or salicylic acid in the presence of a usual transesterification catalyst. be able to.

In carrying out the present invention, a method for producing a polycarbonate resin from one or more bisphenol compounds and phosgene is specifically described in the presence of an inert solvent such as methylene chloride or 1,2-dichloromethane as an acid acceptor for bisphenol compounds. The reaction is carried out while introducing phosgene into an aqueous alkaline solution or pyridine.

When an alkaline aqueous solution is used as the acid acceptor, the reaction rate is increased when a tertiary amine such as trimethylamine or triethylamine or a quaternary ammonium compound such as tetrabutylammonium chloride or benzyltributylammonium bromide is used as a catalyst.

The catalyst may be added from the beginning, or any method such as adding the oligomer after forming it to make it into a high molecular weight may be used.

The monofunctional phenol compound containing fluorine, which is used as the terminal terminating agent in the present invention, is used in the coexistence with the bisphenol compound. As a method therefor, it is allowed to coexist with the bisphenol compound from the beginning.

(B) After an oligomer made of a bisphenol compound is produced, any method such as coexistence in increasing the molecular weight can be used.

Further, other monofunctional phenol represented by the following general formula (II) may be used in combination during the polymerization so long as the properties of the polycarbonate obtained by the present invention are not impaired, and the obtained fluorine-containing polycarbonate is represented by the general formula The monofunctional phenol represented by (II) may be mixed with another polycarbonate used as a terminal terminating agent by an ordinary mixing method.

General formula (II) Specific examples include phenol, promphenol, chlorophenol, and alkyl-substituted phenols such as p-tert-butylphenol.

The total amount of monofunctional phenolic compound used as an end-capping agent in the present invention is determined by the desired molecular weight. That is, when used in a small amount relative to the bisphenol compound used, a high molecular weight resin is obtained, while when used in a large amount, a low molecular weight resin is obtained. Preferably,
It is 1.0 to 10.0 mol%, preferably 2.0 to 8.0 mol%, based on the bisphenol compound used. That is, 1.0
If it is less than mol%, a high-molecular weight polycarbonate can be obtained, but since the molecular weight is too high, the effect of improving the fluidity by the terminal stopper of the present invention cannot be obtained. On the other hand, when it is 10 mol% or more, the fluidity is remarkably improved, but the molecular weight is too small to obtain only a molded product having insufficient strength.

Further, the ratio of the fluorine-containing terminal stopper represented by the general formula (I) to the total terminal stopper is preferably 0.1 to 100 mol%. That is, the amount of the terminator of the present invention can be arbitrarily selected within the above range depending on the need for improvement of fluidity and releasability, but at 0.1 mol% or less, the terminator of the present invention is a terminator. The effect of improving these is small because the ratio of the compound bonded to is too small.

The resin of the present invention is a polycarbonate resin having a fluorine-containing substituent at the terminal as described above, which improves the fluidity “Q value” and also lowers the surface energy, resulting in a large “contact angle”. Become.

Here, the Q value is a melt viscosity measured by a flow tester, and represents the amount of molten resin flowing out from a nozzle of 1 mmφ × 10 mmL at a pressure of 280 ° C. and 160 kg / cm ² in units of cc / sec. .

As the contact angle, the value obtained by dropping a small amount of water on the molded piece at 23 ° C. was used.

Incidentally, the resin of the present invention, within the range of not impairing the properties, known additives such as heat stabilizers, release agents, antistatic agents, heat-sensitive stabilizers, dyes, pigments, fillers and the like, which are usually added to plastics. Can be included.

〔Example〕

Hereinafter, specific examples of the method for producing the polycarbonate used in the present invention and the properties of the obtained resin will be described with reference to Examples. All parts in the examples are parts by weight.

Reference Example 1 1H, 1H, 2H, 2H-perfluorodecane-1-ol 100
1 part of paratoluenesulfonic acid and 70 parts of methyl salicylate were added to the flask, and the reaction was continued at 150 ° C. until the methanol flowed out. After the reaction, vacuum distillation (147
The reaction product was obtained by ℃, 5mmHg).

The obtained product was salicylic acid 1H, 1H, 2H,
It was identified as a 2H-perfluorodecyl ester.

Example 1 (a) Production of oligomer Bisphenol A 100 parts Sodium hydroxide 37 parts Water 670 parts The above mixture was charged into a reactor equipped with a stirrer and stirred at 800 rpm with 360 parts of methylene chloride and salicylic acid prepared in Reference Example 1. 1H, 1H, 2H, 2H-perfluorodecyl ester
8.2 parts were added. Then, 54 g of phosgene was blown in during 60 minutes while cooling so that the mixed solution was kept at 20 ° C. or lower to carry out oligomerization. After the reaction was completed, only the methylene chloride solution containing the polycarbonate oligomer was collected.

The analysis results of the methylene chloride solution of the obtained oligomer were as follows.

Oligomer concentration 22.7% (Note 1) Terminal chloroformate group concentration 0.51 standard (Note 2) Terminal phenolic hydroxyl group concentration 0.02 standard (Note 3) (Note 1) Measured by evaporation to dryness.

(Note 2) The aniline hydrochloride obtained by reacting with aniline was neutralized and titrated with 0.2N aqueous sodium hydroxide solution.

(Note 3) Colorimetric determination at 546 nm of color development when dissolved in titanium tetrachloride and acetic acid solution.

The oligomer solution obtained by the above method is hereinafter abbreviated as oligomer solution A.

(B) Production of polymer Oligomer solution A 460 parts Methylene chloride 160 parts The above mixture was charged into a reactor equipped with a stirrer and stirred at 600 rpm. Furthermore, an aqueous solution having the following composition, that is, 160 parts of a 10% by weight sodium hydroxide aqueous solution and 1.9 parts of a 2% by weight aqueous triethylamine solution were added, and interfacial polymerization was carried out for 3 hours.

After the polymerization solution was separated into a water layer and a methylene chloride layer containing polycarbonate, the methylene chloride layer was washed successively with an aqueous sodium hydroxide solution, an aqueous hydrochloric acid solution and demineralized water, and finally the methylene chloride was evaporated to take out the resin. The viscosity average molecular weight of the obtained pellets was 26,400.

Example 2 Oligomer solution A 460 parts Methylene chloride 160 parts Salicylic acid 1H, 1H, 2H, 2H-perfluorodecyl ester
3.2 parts The above mixture was charged into a reactor equipped with a stirrer and stirred at 600 rpm. Furthermore, an aqueous solution having the following composition, that is, 160 parts of a 10% by weight sodium hydroxide aqueous solution and 1.9 parts of a 2% by weight aqueous triethylamine solution were added, and interfacial polymerization was carried out for 3 hours.

A polycarbonate resin was produced from the obtained polymerization liquid in the same manner as described in Example 1 (b). The viscosity average molecular weight of the obtained pellets was 19,600.

Comparative Example 1 (a) Production of oligomer Bisphenol A 100 parts by weight Sodium hydroxide 37 parts by weight Water 670 parts by weight The above mixture was charged into a reactor equipped with a stirrer, and 320 parts of methylene chloride was added while stirring at 800 rpm. Then, while cooling the mixed solution to 20 ° C or less, 6 g of phosgene 54 g was added.
It was blown in during 0 minutes to carry out oligomerization. After the reaction was completed, only the methylene chloride solution containing the polycarbonate oligomer was collected.

The analysis results of the methylene chloride solution of the obtained oligomer were as follows.

Oligomer concentration 24.3% (Note 1) Terminal chloroformate group concentration 0.82N (Note 2) Terminal phenolic hydroxyl group concentration 0.08N (Note 3) (Notes 1 to 3 are the same as above) Oligomer solution obtained by the above method Is hereinafter referred to as an oligomer solution B for short.

(B) Polymer production example Oligomer solution B 440 parts Methylene chloride 170 parts P-tert-butylphenol 2.0 parts The above mixture was charged into a reactor equipped with a stirrer and stirred at 600 rpm. Further, an aqueous solution having the following composition, that is, 235 parts of a 10% by weight sodium hydroxide aqueous solution and 1.9 parts of a 2% by weight aqueous triethylamine solution was added, and interfacial polymerization was carried out for 3 hours.

A polycarbonate resin was produced from the obtained polymerization liquid in the same manner as described in Example 1 (b).

The viscosity average molecular weight of the obtained polymer was 20,100.

The physical properties of the polycarbonate resins obtained in Example 1-2 and Comparative Example 1 are summarized in Table-1.

1) PFDS: salicylic acid 1H, 1H, 2H, 2H-perfluorodecyl ester PTBP: p-tert-butylphenol 2) Film cast from methylene chloride
Measure the contact angle with water at 23 ℃.

3) Measured with a flow tester at 280 ℃ and 160kg load.

4) Measured by DSC.

〔The invention's effect〕

As described above, the polycarbonate resin of the present invention has a large Q value and excellent fluidity when compared with a conventional polycarbonate at the same viscosity average molecular weight. Further, the polycarbonate of the present invention has a low surface energy as can be seen from the large contact angle, and the releasability is improved as compared with the conventional polycarbonate. Therefore, when injection molding is performed to obtain various molded articles, the molding cycle can be shortened without lowering the viscosity average molecular weight more than necessary without impairing the strength of the molded article, and high productivity can be achieved. is there.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-63-3022 (JP, A) JP-A-63-223037 (JP, A) JP-A 64-40523 (JP, A) JP-A 64-- 79228 (JP, A)

Claims (4)

(57) [Claims] 1. A method for producing an aromatic polycarbonate resin by reacting a bisphenol compound with phosgene or a carbonic acid ester, wherein a fluorine-containing monofunctional phenol represented by the following general formula (I) is used as a terminal stopper. A method for producing an aromatic polycarbonate resin, comprising: General formula (I) 2. A fluorine-containing monofunctional phenol as an endcapping agent is contained in an amount of 0.1 to 100 mol% based on the total amount of the endcapping agent, and 99.9 to 0 mol% of the endcapping agent represented by the following general formula (II). The method for producing an aromatic polycarbonate resin according to claim 1, wherein General formula (II) 3. The method for producing an aromatic polycarbonate resin according to claim 1 or 2, wherein the viscosity average molecular weight of the aromatic polycarbonate resin is 9,500 to 100,000. 4. A bisphenol compound represented by the general formula (II
The method for producing an aromatic polycarbonate resin according to any one of claims 1 to 3, wherein the bisphenol represented by I) is used for polymerization. General formula (III)