JPH1129633A - Production of granular polyarylate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a granular polyarylate not containing an active molecular terminal and little amount of fine powder and having high bulk density and good handlability. SOLUTION: This method for continuously producing a granular polyarylate comprises feeding and mixing the methylene dichloride solution of the polyarylate and water to a polyarylate-water dispersion heated and stirred in a stirring tank 1 at 40-100 deg.C at the atmospheric pressure or a reduced pressure, distilling off the methylene dichloride and simultaneously circulating the slurry through a circulation line disposed on the stirring tank 1, and extracting a part of the slurry from the circulation line. Therein, the polyarylate methylene dichloride solution and water are preliminarily mixed and subsequently fed into the stirring tank 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing granular polyarylate, and more particularly to a method for producing granular polyarylate from a methylene chloride solution of polyarylate.

[0002]

2. Description of the Related Art Conventionally, various methods have been proposed for producing granular polyarylate from a methylene chloride solution after interfacial polymerization. These methods include, for example, adding a methylene chloride solution of polyarylate after interfacial polymerization to a poor solvent such as an alcohol that does not dissolve polyarylate and is compatible with methylene chloride under strong stirring. A solvent precipitation method, a methylene chloride solution of polyarylate is heated under normal pressure or reduced pressure in an extruder to distill off the solvent to produce a polyarylate powder, a kneader method for spraying the polyarylate solution. The solvent is distilled off, for example, a spray-drying method for producing a fine powder.

In the production of polyarylate powder by the above-mentioned solvent precipitation method, a poor solvent must be used in an amount of about 20 times the volume of a methylene chloride solution, which is extremely costly and requires strict explosion-proof equipment. Was. Furthermore, the powder obtained by this method has a problem that the bulk density is low and handling is very poor. In addition, in the production of polyarylate powder by a kneader method, polyarylate is solidified as a block-like mass, so that methylene chloride tends to remain inside, and a relatively high temperature is required. Has the problem that the polyarylate is colored. In the production of polyarylate powder by a spray drying method, it is necessary to adjust the viscosity of a methylene chloride solution. For example, when a high-viscosity solution is used, it is difficult to obtain polyarylate as a powder because it becomes fibrous. Further, when a solution having a low viscosity is used after dilution, the particle size of the obtained powdery polyarylate is as small as 100 μm or less, and there is a problem that handling is extremely poor.

[0004] As a method of solving such a problem,
Japanese Patent Application Laid-Open No. Sho 50-139156 discloses that from room temperature to 20
A solution of polyarylate in methylene chloride at 0 ° C.
There is disclosed a method for producing a granular polyarylate in which a granulation action is completed by injecting into a warm water or a space above the warm water kept at 0 ° C. through pores to complete a granulating action in the warm water under stirring.
In this method, a blade with a blade is installed in a stirring tank, and the blade is pulverized by rotating the blade at a high speed of 3500 rpm. Therefore, there is a problem that a particle size distribution is widened and fine powder is generated. Was. In addition, soft and sticky polyarylate particles with a small amount of methylene chloride remaining collide with the vessel wall at high speed due to the high speed rotation of the stirring blade.
There is a fatal problem that the particles easily adhere to the vessel wall, and if the operation is performed for a long time, the resin mass of the adhered particles grows and cannot be stirred. Further, in this method, a special device such as a bladed stirring blade capable of rotating at high speed was required.

In Japanese Patent Application Laid-Open No. 4-202220, polyarylate is polymerized at such a high concentration that a gel or a solid substance is precipitated during the polymerization. A production method for depositing polyarylate in a powder form has been proposed. According to this method, even if a powder of polyarylate is obtained, gelation occurs during polymerization, so that the acid chloride terminal of polyarylate is not deactivated and unreacted monomers remain inside the polymer. However, there is a problem that the color tone and the thermal stability are deteriorated.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyarylate which does not contain an active terminal and which can be easily and continuously used for a long period of time without the generation of fine powder. To provide a manufacturing method.

[0007]

Means for Solving the Problems The present inventors supplied and mixed a polyarylate methylene chloride solution into a stirred polyarylate-water slurry maintained at a specific temperature in a stirring tank and mixed. It has been found that by circulating the slurry while distilling off the methylene chloride in the slurry and stirring the slurry in the circulation line, a granular polyarylate having a high halo density and a small amount of fine powder can be produced.
However, it was found that when the methylene chloride solution of the polymer was supplied as it was, resin adhered to the stirring tank, and it was difficult to perform continuous and stable operation. As a result of intensive studies to solve such problems, it was found that the adhesion of resin to the stirring tank was caused by poor dispersion of the supplied polyarylate methylene chloride solution in the stirring tank. Was. However, when the supplied polymer solution and water are preliminarily mixed to form a water dispersion liquid of the polymer solution and supplied into the polyarylate-water slurry in the stirring tank, adhesion to the stirring tank can be suppressed. The inventors have found and completed the present invention.

That is, according to the present invention, a methylene chloride solution of polyarylate and water are supplied and mixed into a polyarylate-water slurry heated to 40 to 100 ° C. at normal pressure or reduced pressure in a stirring tank. A method for continuously producing granular polyarylate by circulating the slurry through a circulation line provided in a stirring tank while distilling off methylene chloride, and extracting a part of the slurry from the circulation line. The present invention relates to a method for producing granular polyarylate, wherein a methylene chloride solution of arylate and water are preliminarily mixed and then supplied to a stirring tank.

[0009]

Next, a method for producing a granular polyarylate of the present invention will be described in detail. In the present invention, the polyarylate is an amorphous aromatic polyester substantially composed of a dihydric phenol and an aromatic dicarboxylic acid.

In the present invention, preferred as the dihydric phenol component constituting the polyarylate resin are bis (4-hydroxyphenyl) methane and 1,1-bis (4
-Hydroxyphenyl) ethane, bis (4-methyl-2)
-Hydroxyphenyl) methane, bis (3,5-dimethyl-4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-
Bis (4-hydroxyphenyl) -4-methylpentane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3 , 5-dimethyl-4-
(Hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,1-bis (4-hydroxyphenyl) -2-ethylhexane,
2,2-bis (3-phenyl-4-hydroxyphenyl) propane, bis (3-methyl-4-hydroxyphenyl) methane, 4,4′-biphenol, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4
-Hydroxyphenyl) -2-methylpropane,

Bis (4-hydroxyphenyl) phenylmethane, 2,2-bis (4-hydroxyphenyl) octane, 1,1-bis (3-methyl-4-hydroxyphenyl) cyclohexane, 2,2-bis (3 -Allyl-4
-Hydroxyphenyl) propane, 2,2-bis (3-
Isopropyl-4-hydroxyphenyl) propane,
2,2-bis (3-tertbutyl-4-hydroxyphenyl) propane, 2,2-bis (3-secbutyl-
4-hydroxyphenyl) propane, bisphenolfluorene, 1,1-bis (2-methyl-4-hydroxy-5-tertbutylphenyl) -2-methylpropane, 4,4 ′-[1,4-phenylene-bis ( 2-propylidene) -bis (3-methyl-4-hydroxyphenyl)], 1,1-bis (3-phenyl-4-hydroxyphenyl) cyclohexane,

4,4'-dihydroxyphenyl ether, bis (2-hydroxyphenyl) methane, 2,4 '
-Methylenebisphenol, bis (3-methyl-4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) propane, 1,1-bis (2-hydroxy-5-methylphenyl) ethane, 1,1 -Screw (4-
Hydroxyphenyl) -3-methyl-butane, bis (2
-Hydroxy-3,5-dimethylphenyl) methane,
1,1-bis (4-hydroxyphenyl) cyclopentane, 1,1-bis (3-methyl-4-hydroxyphenyl) cyclopentane, 3,3-bis (4-hydroxyphenyl) pentane, 3,3-bis (3-methyl-4-hydroxyphenyl) pentane, 3,3-bis (3,5-
Dimethyl-4-hydroxyphenyl) pentane, 2,2
-Bis (2-hydroxy-3,5-dimethylphenyl)
Propane, 2,2-bis (4-hydroxyphenyl) nonane,

1,1-bis (3-methyl-4-hydroxyphenyl) -1-phenylethane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) cyclohexane, 2,2-bis (4 -Hydroxyphenyl) decane, 1,1-bis (4-hydroxyphenyl) decane, 1,1-bis (2-hydroxy-3-tertbutyl-5-methylphenyl) methane, bis (4-hydroxyphenyl) diphenylmethane, Terpene diphenol, 1,1-bis (3-tertbutyl-4-hydroxyphenyl) cyclohexane, 1,1-bis (2-methyl-4-hydroxy-5-tertbutylphenyl)-
2-methylpropane, 2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane,

Bis (3,5-ditertbutyl-4-hydroxyphenyl) methane, bis (3,5-disecbutyl-4-hydroxyphenyl) methane, 1,1-bis (3-cyclohexyl-4-hydroxy) Phenyl) cyclohexane, 1,1-bis (2-hydroxy-3,5-
Ditertbutylphenyl) ethane, 1,1-bis (3
-Nonyl-4-hydroxyphenyl) methane, 2,2-
Bis (3,5-ditertbutyl-4-hydroxyphenyl) propane, 1,1-bis (2-hydroxy-3,
5-ditertbutyl-6-methylphenyl) methane,
1,1-bis (3-phenyl-4-hydroxyphenyl) -1-phenylethane, 4,4-bis (4-hydroxyphenyl) pentanoic acid, α, α′-bis (4-hydroxyphenyl) acetic acid butyl ester 1,1-bis (3-fluoro-4-hydroxyphenyl) methane, bis (2-hydroxy-5-fluorophenyl) methane,

2,2-bis (4-hydroxyphenyl)
-1,1,1,3,3,3-hexafluoropropane,
2,2-bis (3-fluoro-4-hydroxyphenyl) propane, 1,1-bis (3-fluoro-4-hydroxyphenyl) -1-phenylmethane, 1,1-bis (3-fluoro-4-hydroxy Phenyl) -1- (p
-Fluorophenyl) methane, 1,1-bis (4-hydroxyphenyl) -1- (p-fluorophenyl) methane, 2,2-bis (3-chloro-4-hydroxy-5-
Methylphenyl) propane, 2,2-bis (3,5-dichloro-4-hydroxyphenyl) propane, 2,2-
Bis (3-chloro-4-hydroxyphenyl) propane, 1,1-bis (3,5-dibromo-4-hydroxyphenyl) methane,

2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, 2,2-bis (3-nitro-4-hydroxyphenyl) propane, 3,3'-dimethyl-4,4 ' -Biphenol, 3,3 ', 5,5'
-Tetramethyl-4,4'-biphenol, 3,3 ',
5,5′-tetratertbutyl-4,4′-biphenol, bis (4-hydroxyphenyl) ketone (or 4,4′-dihydroxybenzophenone), 3,3′-
Difluoro-4,4'-biphenol, 3,3 ', 5
5'-tetrafluoro-4,4'-biphenol, bis (4-hydroxyphenyl) dimethylsilane, bis (4
-Hydroxyphenyl) sulfone, bis (3-methyl-
4-hydroxyphenyl) sulfone, bis (3,5-dimethyl-4-hydroxyphenyl) sulfone, bis (3,5-dibromo-4-hydroxyphenyl) sulfone,

Bis (4-hydroxyphenyl) thioether, bis (3-methyl-4-hydroxyphenyl) ether, bis (3-methyl-4-hydroxyphenyl)
Thioether, bis (3,5-dimethyl-4-hydroxyphenyl) ether, bis (3,5-dimethyl-4-
(Hydroxyphenyl) thioether, 1,1-bis (2,3,5-trimethyl-4-hydroxyphenyl)
-1-phenylmethane, 2,2-bis (4-hydroxyphenyl) dodecane, 2,2-bis (3-methyl-4-
Hydroxyphenyl) dodecane, 2,2-bis (3,5
-Dimethyl-4-hydroxyphenyl) dodecane,

1,1-bis (3-tertbutyl-4-
(Hydroxyphenyl) -1-phenylethane, 1,1-
Bis (3,5-ditertbutyl-4-hydroxyphenyl) -1-phenylethane, 1,1-bis (2-methyl-4-hydroxy-5-cyclohexylphenyl)-
2-methylpropane, 1,1-bis (2-hydroxy-
3,5-ditertbutylphenyl) ethane, 2,2-
Bis (4-hydroxyphenyl) propanoic acid methyl ester, 2,2-bis (4-hydroxyphenyl) propanoic acid ethyl ester, isatin bisphenol, isatin biscresol, 2,2 ′, 3,3 ′, 5,5 '-Hexamethyl-4,4'-biphenol, bis (2-hydroxyphenyl) methane, 2,4'-methylenebisphenol,

1,2-bis (4-hydroxyphenyl)
Ethane, 2- (4-hydroxyphenyl) -2- (2-
(Hydroxyphenyl) propane, bis (2-hydroxy-3-allylphenyl) methane, 1,1-bis (2-hydroxy-3,5-dimethylphenyl) -2-methylpropane, 1,1-bis (2-hydroxy- 5-tert
Butylphenyl) ethane, bis (2-hydroxy-5-
Phenylphenyl) methane, 1,1-bis (2-methyl-4-hydroxy-5-tertbutylphenyl) butane, bis (2-methyl-4-hydroxy-5-cyclohexylphenyl) methane, 2,2-bis ( 4-hydroxyphenyl) pentadecane, 2,2-bis (3-methyl-4-hydroxyphenyl) pentadecane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) pentadecane,

1,2-bis (3,5-ditertbutyl-4-hydroxyphenyl) ethane, bis (2-hydroxy-3,5-ditertbutylphenyl) methane,
2,2-bis (3-styryl-4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) -1- (p-nitrophenyl) ethane, bis (3
5-difluoro-4-hydroxyphenyl) methane, bis (3,5-difluoro-4-hydroxyphenyl)-
1-phenylmethane, bis (3,5-difluoro-4-
Hydroxyphenyl) diphenylmethane, bis (3-fluoro-4-hydroxyphenyl) diphenylmethane,
2,2-bis (3-chloro-4-hydroxyphenyl)
Propane, 3,3 ′, 5,5′-tetratertbutyl-2,2′-biphenol, 2,2′-diallyl-4,
4'-biphenol,

1,1-bis (4-hydroxyphenyl)
-3,3-dimethyl-5-methyl-cyclohexane,
1,1-bis (4-hydroxyphenyl) -3,3-dimethyl-5,5-dimethyl-cyclohexane, 1,1-
Bis (4-hydroxyphenyl) -3,3-dimethyl-
4-methyl-cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3-dimethyl-5-ethyl-cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3-dimethyl-5 Methyl-cyclopentane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) -3,3-dimethyl-5-methyl-cyclohexane, 1,1-bis (3,5-diphenyl-4-hydroxy) Phenyl) -3,3-dimethyl-5-methyl-cyclohexane, 1,1-bis (3-methyl-4-hydroxyphenyl) -3,3-dimethyl-5-methyl-cyclohexane,

1,1-bis (3-phenyl-4-hydroxyphenyl) -3,3-dimethyl-5-methyl-cyclohexane, 1,1-bis (3,5-dichloro-4-hydroxyphenyl) -3 , 3-dimethyl-5-methyl-
Cyclohexane, 1,1-bis (3,5-dibromo-4
-Hydroxyphenyl) -3,3-dimethyl-5-methyl-cyclohexane, resorcinol, hydroquinone, 1,2-dihydroxybenzene, 1,4-di (4-
(Hydroxyphenyl) -p-menthane, 1,4-di (3
-Methyl-4-hydroxyphenyl) -p-menthane,
Terpene diphenols such as 1,4-di (3,5-dimethyl-4-hydroxyphenyl) -p-menthane and the like can be mentioned.

Further, a part of the dihydric phenol may be replaced with ethylene glycol, propylene glycol, butanediol, pentanediol, or the like as long as the properties of the polymer are not impaired.
It may be replaced with a dihydric alcohol such as hexanediol, heptanediol, octanediol, dodecanediol, neopentyl glycol, cyclohexanediol, 1,4-dihydroxymethylcyclohexane, and the like.

Further, in the present invention, the aromatic dicarboxylic acid component constituting the polyarylate includes, for example, terephthalic acid, isophthalic acid, orthophthalic acid, methyl group,
Phthalic acid derivatives in which one or two alkyl groups such as ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group and t-butyl group are substituted, 1,5-naphthalenedicarboxylic acid Acid, naphthalenedicarboxylic acid derivatives such as 2,6-naphthalenedicarboxylic acid,
4,4′-dicarboxybiphenyl, diphenic acid, 4,
Examples thereof include 4′-dicarboxydiphenyl ether, bis (p-carboxyphenyl) alkane, and 4,4′-dicarboxydiphenylsulfone, and one or more of these may be used in combination. Of these, terephthalic acid and isophthalic acid are preferred, and a particularly preferred mixture is terephthalic acid and isophthalic acid. The aromatic dicarboxylic acid component may be used as a free aromatic dicarboxylic acid or as an aromatic dicarboxylic acid dihalide.

In the present invention, a part of the above-mentioned aromatic dicarboxylic acids may be replaced with other aliphatic dicarboxylic acids as long as their properties are not substantially impaired. Examples of such dicarboxylic acids include dicarboxymethylcyclohexane, cyclohexanedicarboxylic acid, adipic acid, sebacic acid, glutaric acid, dodecane diacid, and the like.

In the present invention, the terminal of the granular polyarylate is not only phenol but also o, m, p-cresol, dimethylphenols, o, m, p-ethylphenol,
o, m, pn-propylphenol, o, m, p-isopropylphenol, o, m, pn-butylphenol, o, m, p-isobutylphenol, o, m, p
-Sec-butylphenol, o, m, p-tert-
Monohydric phenols such as butylphenol and monohydric alcohols such as methanol, ethanol, n-propanol, isopropanol, butanol, pentanol, hexanol, dodecyl alcohol, stearyl alcohol, benzyl alcohol, and phenethyl alcohol, acetic acid, propionic acid, octanoic acid, Monovalent carboxylic acids such as cyclohexanecarboxylic acid, benzoic acid, toluic acid, phenylacetic acid, p-tert-butylbenzoic acid, p-methoxyphenylacetic acid, acid chlorides such as benzoic acid chloride, methanesulfonyl chloride and phenylchloroformate May be blocked.

The number average molecular weight of the polyarylate obtained by the method of the present invention is 5,000 or more, preferably 10,000 to 300,000 in terms of polystyrene measured by gel permeation chromatography. If the molecular weight is less than 5,000, the mechanical properties of the polymer decrease, while if it exceeds 300,000, the processability at the time of melting decreases, which is not preferable.

The granular polyarylate obtained by the method of the present invention has an average particle size of 500 μm or more. If the average particle diameter is less than 500 μm, the particles are too fine and handling becomes poor. Preferably, the average particle size is 1000 μm or more. Although various methods for measuring the average particle diameter have been proposed, the average particle diameter in the present invention is simply referred to as the average particle diameter of the number average of the particle diameters of the respective particles directly measured by an optical microscope.

Further, the granular polyarylate obtained by the method of the present invention has a small proportion of fine powder. If the percentage by weight of passing through a 250 μm sieve is taken as the definition of the proportion of fines, the granular polyarylate obtained by the method of the invention has a passing percentage by weight of 5%.
%, Preferably 3% or less. If the amount of the fine powder exceeds 5%, it is not preferable because scattering of dust occurs when the fine powder is supplied to the hopper during molding or extrusion.

The bulk density of the granular polyarylate obtained by the method of the present invention is 0.15 or more, preferably 0.15.
25 or more. If the bulk density is less than 0.15, handling tends to be poor, which is not preferable. The bulk density is
It can be measured by a known method. In the present invention, the bulk density without tapping is employed.

Next, the method for producing the granular polyarylate of the present invention will be described in more detail. In the present invention, the polyarylate may be polymerized by any method such as an interfacial polymerization method or a melt polymerization method, but after the interfacial polymerization, a liquid-liquid separation of the polyarylate in an organic solvent solution, in particular, chloride The use of a methylene solution is preferable in that the operation can be continuously performed. In the interfacial polymerization, in the presence of a polymerization catalyst, an aqueous alkali solution in which a dihydric phenol compound is dissolved, and in some cases, an aqueous alkali solution in which a terminal blocking agent is also dissolved, and a methylene chloride solution of an aromatic dicarboxylic acid dihalide are mixed. And 0.5 ~
The reaction is performed by reacting the dihydric phenol with the aromatic dicarboxylic acid dihalide while stirring for 5 hours.

The amount of methylene chloride used during the interfacial polymerization is usually preferably used such that the polymer concentration becomes 5 to 25% by weight, more preferably 10 to 25% by weight. If the polymer concentration exceeds 25% by weight, the polymer may become a gel during the polymerization and precipitate. It is difficult to deactivate active terminals such as acid halide groups in the gelled polymer, and such a polymer adversely affects the color tone during molding. The amount of the alkaline water is usually in the range of 1 to 3 times the volume ratio of methylene chloride.
Examples of the alkali used in the reaction include sodium hydroxide and potassium hydroxide.

Further, as a polymerization catalyst, trimethylamine, triethylamine, tri-n-butylamine, tri-n-propylamine, tri-isopropylamine, trihexylamine, tridecylamine, N, N-dimethylcyclohexylamine, pyridine, quinoline Tertiary amines such as dimethylaniline, trimethylbenzylammonium halide, tetramethylbenzylammonium halide, triethylbenzylammonium halide, tri-n-butylbenzylammonium halide,
Quaternary ammonium salts such as tetra-n-butylammonium halide; trimethylbenzylphosphonium halide; tetramethylbenzylphosphonium halide; triethylbenzylphosphonium halide; tri-n-butylbenzylphosphonium halide; tetra-n-butylphosphonium halide; Quaternary phosphonium salts such as phenylbenzylphosphonium halide, tetraphenylphosphonium halide, 18-crown-6, 1
8-benzocrown-6,18-dibenzocrown-
Examples thereof include crown ethers such as 6,15-crown-5, and quaternary ammonium salts are particularly preferred from the viewpoints of polymerization rate and cost.

In the production method of the present invention, additives such as an antioxidant such as a hindered phenol compound, a phosphorous acid compound, a hindered amine compound or a thioether compound, and a colorant are added to the methylene chloride solution after polymerization. In addition, granular polyarylate particles containing various additives can be obtained.

After completion of the interfacial polymerization, the reaction is stopped and neutralized by adding an acid, and an aqueous phase containing salts and unreacted monomers and a methylene chloride phase in which polyarylate is dissolved are decanted, centrifuged, etc. Separate using known methods. As the acid used at this time, hydrochloric acid, sulfuric acid, phosphoric acid, acetic acid and the like are preferable. Further, the methylene chloride phase can be washed with water to remove residual salts and monomers, and then used in the method of the present invention.

In the method of the present invention, after the methylene chloride solution of the polyarylate obtained as described above is previously mixed with water, the mixture is preferably placed in a stirring tank in which the polyarylate-water slurry is mixed. The arylate-water slurry is continuously or intermittently supplied to a stirring tank in which the slurry is circulated and mixed, and the methylene chloride is distilled off while maintaining the suspension state.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic diagram showing an example of an apparatus for implementing the present invention. In FIG. 1, 1 is a stirring tank, 2 is a stirrer, 3 is a solution supply pipe, 4 is a makeup water supply pipe, 5 is a methylene chloride distilling pipe, 6 is a granular polyarylate slurry extraction pipe, 7 is a slurry pump, 8 is a circulating slurry stirrer, 9 is a product extraction pipe, 10 is a circulating slurry introduction pipe,
Numeral 11 indicates a polyarylate solution-water mixer, and numeral 12 indicates a polyarylate solution-water mixed liquid introducing tube.

The stirring tank 1 is not particularly limited as long as it can maintain a methylene chloride solution of polyarylate in suspension in water. An ordinary stirring tank can be used, and it is preferable to install three or four baffles from the viewpoint of mixing efficiency. As the shape of the stirring blade of the stirrer 2 used in the stirring tank 1, the slurry tends to float with the evaporation of the methylene chloride. By way of example, an inclined paddle type or an inclined turbine type can be appropriately selected from two blades to six blades. The stirring speed is not particularly limited as long as the granulated particles do not collide and adhere to the tank wall at high speed, but from the viewpoint of uniformly dispersing the slurry and preventing floating, and using a general-purpose and inexpensive stirring device. Although it depends on the shape of the stirring blade, it is usually 100 to 800 rpm.
It is sufficient if it is within the range of m. Further, the stirring tank 1 is provided with a mixed liquid introducing pipe 12 at an upper part, a slurry extracting pipe 6 at a lower part, and a circulating slurry introducing pipe 10 at an upper part. The slurry extraction pipe 6 and the circulating slurry introduction pipe 10 constitute an external circulation path of the slurry. Slurry extraction pipe 6
Is provided with a slurry pump 7, and a circulating slurry stirring device 8 and a product extraction pipe 9 are provided in the subsequent stream. After the granular polyarylate-water slurry extracted from the slurry extraction pipe 6 is subjected to dispersion treatment through the circulation slurry stirring device 8, a part is extracted from the product extraction pipe 9 for the product, and the remainder is circulated from the circulation slurry introduction pipe 10. Meanwhile, the polyarylate solution-water mixture is continuously or intermittently supplied into the slurry liquid phase through the mixture introduction pipe 12.

The temperature of the aqueous medium for evaporating methylene chloride in the stirring tank 1 can be usually from 40 to 98 ° C., but taking into account the evaporation rate of methylene chloride and the amount of water evaporation,
~ 90 ° C is preferably used. In addition, since the circulated polyarylate slurry and the polyarylate solution-water mixture come into contact with each other while the methylene chloride evaporates in the stirring tank 1 and coalesce, the slurry is extracted from the slurry extraction pipe 6 by the slurry pump 7. Then, the particles are passed through the circulating slurry stirrer 8 and dispersed again. The circulating slurry stirring device 8 is not particularly limited as long as it can continuously disperse the coalesced particles, but a wet pulverizer is preferable.

In the present invention, it is essential that the polyarylate solution and water are supplied to the mixer 11 and mixed beforehand, and then supplied to the stirring tank 1 through the mixed liquid introduction pipe 12. The mixer 11 at this time is not particularly limited as long as it can uniformly and continuously mix the polymer solution and water, and examples thereof include a premixing tank such as a normal stirring tank, a line homomixer, and a static mixer. can do. The degree of mixing of the polyarylate solution and water in the mixer 11 is such that water and the polyarylate solution are not separated even after being left standing for about 10 seconds. Also,
It is preferable that the mixer 11 be installed as close as possible to the mixture introducing pipe 12. If the time has elapsed after mixing in the mixer 11, the solution and water may be separated before reaching the mixed liquid introduction pipe 12, and the mixing effect may not be obtained.

The concentration of the polyarylate methylene chloride solution supplied to the mixer 11 in the method of the present invention is 5 to 25% by weight, but is 10% in consideration of the production speed.
Preference is given to a concentration of between 25% and 25% by weight. Mixer 1
The volume ratio of the polyarylate methylene chloride solution to water supplied to 1 is determined by the concentration of the polyarylate methylene chloride solution and the slurry concentration in the stirring tank,
Usually, it is in the range of 0.1 to 1. The type of water supplied to the mixer 11 is not particularly limited. The temperature of the water supplied to the mixer is preferably lower than the boiling point of methylene chloride, that is, about 10 to 40 ° C. Water temperature is 40 ℃
Is exceeded, when the polyarylate solution and water come into contact in the mixer 11, the methylene chloride evaporates, and the solution is concentrated.
2 easily adheres to the resin. Also, if the water temperature is 10
If the temperature is lower than ℃, the efficiency of evaporating methylene chloride in the stirring tank decreases depending on the supply amount.

The slurry concentration of the granular polyarylate in the stirring tank 1 is in the range of 3 to 30% by weight, preferably in the range of 5 to 25% by weight. The slurry concentration is
It is preferable to keep it as constant as possible. Usually, it is kept constant by adjusting the supply amount of the polyarylate solution, the supply amount of water, and the extraction amount of the granular polyarylate slurry for the product. As the stirring blade that can be used in the circulating slurry stirring device 8, a known blade such as a propeller, a turbine type, or a paddle type can be used. The diameter of the stirring blade is not particularly limited.
It is preferable to use a stirring blade diameter which is a diameter of 7.

The slurry containing the granular polyarylate extracted from the product extraction pipe 9 is filtered using a known solid-liquid separator, and further dried using a vacuum drier, a fluidized bed drier, or the like. A granular polyarylate is obtained.

[0044]

Next, the present invention will be described in detail with reference to examples and comparative examples. However, the present invention is not limited to these examples, and various modifications and changes can be made without departing from the spirit of the present invention. Application is possible.

[Reference Example 1] (Preparation of polyarylate by interfacial polymerization) In a reaction vessel equipped with a stirring device, 100 parts by weight of 2,2-bis (4-hydroxyphenyl) propane, p-tert
3.4 parts by weight of butylphenol, sodium hydroxide 4
1.4 parts by weight and 0.6 parts by weight of trimethylbenzylammonium chloride were charged and dissolved in 1350 parts by weight of water (aqueous phase). Separately, 93 parts by weight of a terephthalic acid dichloride / isophthalic acid dichloride 1/1 mixture were dissolved in 767 parts by weight of methylene chloride (organic phase).
This organic phase was added to the previously prepared aqueous phase under strong stirring,
The polymerization reaction was performed for 3 hours. Thereafter, 50 parts by weight of acetic acid was added to stop the reaction, the aqueous phase and the organic phase were separated, and the mixture was washed repeatedly with water until the organic phase became neutral to obtain a 17% by weight polyarylate methylene chloride solution.

Example 1 Granular polyarylate was produced using the apparatus shown in FIG. First, 50 ° C. hot water 1 was placed in a stirring tank 1 having a capacity of 250 liters (tank diameter 60 cm).
35 liters of dried polyarylate particles 2
2.95 kg was charged and the slurry concentration was adjusted to 17%. Then, a 17% by weight polyarylate solution of methylene chloride obtained in Reference Example 1 was added to the solution supply pipe 3 through 25.25.
At a speed of 9 kg / hr, hot water at 30 ° C.
At a rate of 25.9 kg / hr, the mixture was supplied to a mixer 11 comprising a static mixer to form a polyarylate solution-hot water mixture. The generated mixture was supplied to the stirring tank 1 through the mixture introduction pipe 12. The circulation of the slurry is performed by the slurry pump 7 through the slurry discharge pipe 6 and the slurry discharge speed Q = 150 liter / min.
The polyarylate particles were re-dispersed and stirred using a circulating slurry stirrer 8 having four turbine-type stirring blades, a part was extracted, and the rest was returned to the stirring tank 1 through a circulating slurry introduction pipe 10. The distilled methylene chloride was drawn out of the stirring tank through the distillation pipe 5. At this time, stirring tank 1
Was kept at 50 ° C., and stirring was performed at 250 rpm using an inclined paddle blade having a blade diameter of 30 cm. With the start of the supply of the polyarylate-methylene chloride solution-hot water mixture, the polyarylate-water-based slurry (resin content: 17% by weight) was withdrawn from the product extraction tube 9 at 30.3 kg / hr (0.49 liter / min), and the remaining Was continuously circulated through the circulating slurry introduction pipe 10. Product extraction tube 9
The granular polyarylate-water slurry extracted therefrom was filtered using a solid-liquid separator and dried to obtain a granular granular polyarylate. In this way, the operation was performed for one week, and the halo density and the particle diameter of the obtained granular polyarylate were measured. The bulk density was measured without tapping, and the particle size was measured using a microscope. After one week, the operation was stopped, all the liquid was drawn out, the inside of the stirring tank was observed, and the adhesion state of the resin in the tank was evaluated. In order to evaluate the degree of increase in resin adhesion, a comparison was made with the case where operation was performed for 2 weeks.

[Example 2] In Example 1, instead of a static mixer, a pre-stirring tank having an actual volume of 10 liters (stirring with four baffles and stirring with a propeller-type stirring blade at 2000 rpm) was used instead of the static mixer. A granular polyarylate was produced in the same manner as in Example 1 except for the difference.

Example 3 A granular polymixer was prepared in the same manner as in Example 1 except that a pipeline homomixer (SL type, manufactured by Tokushu Kika Kogyo Co., Ltd.) was used instead of the static mixer. Arylate was produced.

Comparative Example 1 A granular polyarylate was produced in the same manner as in Example 1, except that the static mixer was removed and a 50 A stainless steel pipe was attached.

Comparative Example 2 Granular polyarylate was prepared in the same manner as in Example 1 except that the methylene chloride solution of polyarylate and water were not mixed and supplied to the stirring tank through separate pipes. Manufactured.

Table 1 shows the evaluation results of the granular polyarylates obtained in Examples 1 to 3 and Comparative Examples 1 and 2, and the evaluation results of the adhesion state of the polyarylate to the stirring tank.

[0052]

[Table 1]

[0053]

According to the present invention, continuous and stable operation can be performed for a long period of time without causing the resin to adhere to the stirring tank, which is extremely advantageous in operability and productivity. Furthermore, the granular polyarylate obtained by the method of the present invention does not contain an active terminal, has a high halo density, and has a small amount of fine powder, so that it can be easily handled, and various raw materials such as molding materials and alloys, raw materials for films, and raw materials for binder resins. Useful as

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an example of an apparatus for implementing the present invention.

[Description of Signs] 1 Stirring tank 2 Stirrer 3 Solution supply pipe 4 Replenishment water supply pipe 5 Distillation pipe 6 Slurry extraction pipe 7 Slurry pump 8 Circulating slurry stirrer 9 Product extraction pipe 10 Circulating slurry introduction pipe 11 Mixer 12 Mixed liquid Introductory pipe

Claims (1)

[Claims] (1) 40 to 10 at normal pressure or reduced pressure in a stirring tank.
A polyarylate-methylene chloride solution and water are supplied to and mixed with the heated polyarylate-water slurry heated to 0 ° C., and while the methylene chloride is being distilled off, the slurry is provided in a circulation line provided in a stirring tank. And a method for continuously producing granular polyarylate by withdrawing a part of the slurry from a circulation line, a methylene chloride solution of polyarylate and water are mixed in advance, and then supplied to a stirring tank. A method for producing a granular polyarylate.