JPH0333729B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing aromatic polyester carbonate granules, and more specifically, the present invention relates to a method for producing aromatic polyester carbonate granules, and more specifically, the production of aromatic polyester carbonate particles having a large bulk density and uniform particle size from an organic solvent solution of aromatic polyester carbonate. The present invention relates to a method for producing group polyester carbonate granules.

[Prior Art] Various methods are known for producing polyester carbonate in an organic solvent, but in any method, at the end of the reaction, polyester carbonate is obtained as a solution dissolved in an organic solvent. Since polyester carbonate is preferably used in extrusion molding, injection molding, rotary molding, etc., and for use as a casting film, it is preferable to use granular materials from the viewpoint of transportation and storage. Therefore, it is necessary to recover the polyester carbonate as a solid material from the above solution. be.

As a method for obtaining a solid from a polyester carbonate solution, first, the method of evaporating the organic solvent from the polyester carbonate solution (Japanese Unexamined Patent Publication No. 55
-25427 Publication). In this method, the solid material is obtained in the form of large lumps, but the problem is that the lumps are hard and cannot be easily crushed.

The second method is to precipitate polyester carbonate by mixing a polyester carbonate solution with a non-solvent such as an alcohol or ketone (Japanese Patent Application Laid-Open No. 139423/1983), but the solid state obtained by this method is The bulk density of the material is not sufficiently satisfactory.

The third method is a method in which a polyester carbonate solution is supplied into a container containing polyester carbonate granules and brought into contact with the granules to evaporate the organic solvent (Japanese Patent Laid-Open No. 141427/1983). In this method, the granules are pre-filled in the container, so the granulation efficiency per container volume is low, and it is difficult to balance the amounts of polyester carbonate solution and granules, and when the amount of solution supplied is large, the granules become sticky. There is a problem.

[Object of the Invention] An object of the present invention is to provide a method for easily and efficiently producing granules with high bulk density and uniform particle size from a polyester carbonate solution.

[Structure of the Invention] The present invention involves supplying an organic solvent solution of aromatic polyester carbonate to a kneader having a grinding mechanism that stores hot water maintained at a temperature equal to or higher than the boiling point of the solvent, and kneading the solution. This method of producing polyester carbonate granules is characterized in that solvent removal and pulverization are carried out simultaneously.

The polyester carbonate targeted by the present invention is produced by reacting divalent phenol with terephthaloyl chloride and/or isophthaloyl chloride and phosgene in the presence of an acid acceptor, water, an organic solvent, and a molecular weight regulator, or Either a divalent phenol and phosgene are reacted in advance to obtain an oligocarbonate having a phenolic hydroxyl group at the end, and this is reacted with terephthaloyl chloride and/or isophthaloyl chloride, or a divalent phenol and terephthaloyl chloride and/or are reacted. Alternatively, it is an amorphous polymer produced by reacting isophthaloyl chloride to obtain an oligoester having a phenolic hydroxyl group at the end, and reacting this with phosgene.

As the divalent phenol used as a raw material for the polyester carbonate, bisphenol is preferable, and 2,2-bis(4-hydroxyphenyl)propane (hereinafter referred to as bisphenol A) is particularly preferable.
) is preferred. Further, part or all of bisphenol A may be replaced with another divalent phenol. Examples of divalent phenols other than bisphenol A include hydroquinone, 4,4'-dihydroxydiphenyl, bis(4-hydroxyphenyl)alkane, bis(4-hydroxyphenyl)cycloalkane, and bis(4-hydroxyphenyl). compounds such as bis(enyl) sulfide, bis(4-hydroxyphenyl) sulfone, bis(4-hydroxydiphenyl) sulfoxide, bis(4-hydroxyphenyl) ether or bis(3,5-
Mention may be made of halogenated bisphenols such as dibromo-4-hydroxyphenyl)propane.

As the terephthaloyl chloride or isophthaloyl chloride, those having a halogen atom such as bromine in the nucleus can also be used.

The organic solvent used for the polyester carbonate thus obtained includes chlorinated hydrocarbons such as methylene chloride, chloroform, and 1,2-dichloroethane, or combinations thereof with solvents such as dioxane, tetrahydrofuran, toluene, and acetone. Among them, methylene chloride is particularly preferred. Although the concentration of the polyester carbonate solution in the present invention is not particularly limited, 3
~30% by weight is preferred.

In the present invention, the polyester carbonate solution is poured into a kneader equipped with a grinding mechanism that stores hot water maintained at a temperature higher than the boiling point of the solvent of the solution to remove the solvent. Temperature above the boiling point, preferably 10-30° above the boiling point of the solvent
Maintain the temperature at about ℃.

An example of a kneader having a crushing mechanism used in the present invention is shown in the drawings. FIG. 1 is a simplified cross-sectional view of a double-arm kneader, and FIG. 2 is a simplified side view of its sigma-type blade. This kneader consists of sigma type blades 1 installed in parallel and a barrel 2 with a jacket for housing the blades, and kneading is carried out by the rotation of the blades. Furthermore, as shown in Fig. 1, this kneader has
A protrusion 3 is provided in the longitudinal direction of the barrel, and a serrated protrusion 4 is provided on the periphery of the sigma-type blade 1.
The serrated projections 4 have a shape as shown in FIG. 3, and the protrusions 3 formed on the inner surface of the barrel 2 have a cross section as shown in FIG. The shape of the protrusion 3 formed on the inner surface of the barrel 2 has a cross section as shown in FIG. As for the unevenness formed on the inner surface of the barrel 2, instead of the protrusions 3 shown in FIGS. 1 and 4, a large number of protrusions 3a may be provided as shown in FIG.

The pitch of such pulverizing ridges and protrusions is preferably about 3 to 20 m/m, and the clearance between the blades and the barrel is preferably 1 to 50 m/m.

The present invention using such a kneader will be specifically explained.

First, hot water at a temperature higher than the boiling point of the solvent is injected into the barrel of the kneader, heated with a jacket and maintained at a predetermined temperature, while the polyester carbonate solution is injected little by little and thoroughly stirred.

This ensures sufficient contact between the solution and the hot water, causing rapid volatilization of the solvent at the contact surface as soon as it is added, resulting in a polyester carbonate concentration of 40 to 80%.
% becomes a sticky substance. When the entire mixture becomes sticky, the hot water is discharged, heat is applied from the jacket, and solvent removal is continued. At this time, the glutinous material is crushed between the blades and the barrel, and becomes granular material with uniform particle size.

In the above explanation, a kneader with crushing teeth was exemplified as a kneader having a crushing mechanism, but the kneader is not limited to this, and any appropriate kneader suitable for carrying out the present invention can be used. . Also,
The heating method is not limited to jacket heating, but any other method such as steam injection may be used.

[Example] This will be explained in more detail below with reference to Examples.

Example 1 A sigma-type blade with saw teeth of the tooth height h ₁ in Fig. 3 of 20 m/m, tooth spacing p ₁ of 20 m/m, and R ₁ of 5 m/m and the inside of the barrel as shown in Fig. 4 Height _h2 is 20m/
m, spacing p ₂ is 20 m/m, R ₂ is 5 m/m, and teeth are provided.
Blade length 1500m/m installed with clearance 3m/m,
50 for a double-arm kneader with a jacket with a blade diameter of 600 m/m.
℃ hot water was added. Among these, ηsp (0.7
g/100ml methylene chloride solution at 20°C)
A 10% by weight solution of 0.43% polyester carbonate in methylene chloride was slowly added dropwise. Needa is 60r.p.
The solution was added dropwise while stirring at m. to obtain a sticky substance. During this time, heat the water from the jacket and bring the water temperature to about 50℃.
It was kept at ℃. After dropping the solution, the hot water was discharged and the solvent was removed and pulverized while stirring.

The particle size of the obtained polyester carbonate granules was 1 to 8 m/m, and the bulk density measured after drying at 120°C for 12 hours was 0.32 g/cm ³ .

Example 2 The same sigma-type blade as in Example 1 and a fifth blade inside the barrel.
The height _h3 of the figure is 20m/m, the spacing _p3 is 20m/m, and _R3 is
Barrel with teeth of 5m/m has a clearance of 3m/
Hot water at 60°C was poured into a double-arm kneader with a jacket attached to the kneader. Among these, 0.47 ηsp (0.7
g/100ml methylene chloride solution at 20°C)
A 10% by weight solution of 0.38% polyester carbonate in methylene chloride was slowly added dropwise. Needa is 60r.p.
The solution was added dropwise while stirring at m. to obtain a sticky substance. During this time, heat the water from the jacket and bring the water temperature to about 50℃.
It was kept at ℃. After dropping the solution, the hot water was discharged, and while stirring, solvent removal and pulverization were carried out.

The particle size of the obtained polyester carbonate granules was 0.5 to 7 m/m, and the bulk density measured after drying at 120°C for 12 hours was 0.34 g/cm ³ .

Comparative Example 1 A double-arm kneader with a jacket similar to that used in Example 1 except that there were no teeth on either the blades or the barrel was heated at 50°C.
of hot water was added. Into this, the polyester carbonate solution used in Example 1 was added dropwise in the same manner as in Example 1 to obtain a glutinous material. After the hot water was discharged, the glutinous material became a large lump and the load became large, making it impossible to stir.

[Effects of the Invention] The polyester carbonate granules obtained by the production method of the present invention are granules with uniform particle size and high bulk density, so they can be suitably used in extrusion molding, rotational molding, etc. as they are. However, when transporting it, it can be packed in a low-volume manner. Furthermore, since the granules are porous, they are easily soluble in solvents. Moreover, in terms of equipment, granules can be obtained from a solution with a single kneader that has a crushing mechanism with grooves or protruding teeth on the blades or barrel, and the power required for the removal is a kneader that does not have the ability to crush. It is not necessary to use a strong solvent to crush the resulting lumps, which is extremely advantageous industrially.

[Brief explanation of drawings]

FIG. 1 is a simplified sectional view of an example of a kneading machine used in the present invention, FIG. 2 is a simplified side view of its stirring blade, and FIG. 3 is a partial side view of serrated teeth formed on the stirring blade. FIG. 4 is a partial side view of a protrusion formed on the barrel, and FIG. 5 is a partial side view of a protrusion formed on the barrel. 1 is a stirring blade, 2 is a barrel, 3 is a serrated tooth formed on the periphery of the stirring blade, and 4 is a protrusion formed on the barrel.

Claims (1)

[Scope of Claims] 1. A solution of aromatic polyester carbonate in an organic solvent is supplied to a kneader equipped with a pulverizing mechanism that stores hot water maintained at a temperature higher than the boiling point of the organic solvent, and the solution is kneaded to remove desorption. A method for producing polyester carbonate granules, characterized in that a solvent and pulverization are carried out simultaneously. 2. The method for producing polyester carbonate granules according to claim 1, wherein the kneader is a kneader having grooves or protruding teeth on its blades and/or barrel.