Production process of poly(arylene sulfide) and production apparatus thereof

Patent metadata

Field	Value
Publication number	US-8981041-B2
Application number	US-201113809505-A
Country	US
Kind code	B2
Filing date	Jul 6, 2011
Priority date	Jul 13, 2010
Publication date	Mar 17, 2015
Grant date	Mar 17, 2015

Abstract

A production process of a poly(arylene sulfide) (PAS), including a polymerization step of forming a PAS from a sulfur source that is an alkali metal (hydro)sulfides and a dihalo-aromatic compound in an organic amide solvent; a separation step of PAS particles; a countercurrent washing step that is a step of washing the PAS particles with water and/or an organic solvent, wherein a downward current of a PAS particle-containing aqueous slurry is continuously brought into countercurrent contact with an upward current of a washing liquid; a PAS particle re-separation step of capturing a washing waste liquid by a PAS particle re-separating unit, in which a micro-slit filter has been installed, and then re-separating the PAS particles from the micro-slit filter, preferably using a backwashing unit, to discharge them; and a collecting step of the PAS particles discharged, and a production apparatus of a poly(arylene sulfide).

First claim

The invention claimed is:

1. A production process of a poly(arylene sulfide), comprising
a polymerization step of subjecting at least one sulfur source selected from the group consisting of alkali metal sulfides and alkali metal hydrosulfides and a dihalo-aromatic compound to a polymerization reaction in an organic amide solvent to form a poly(arylene sulfide);
a separation step of separating poly(arylene sulfide) particles from a reaction mixture containing the poly(arylene sulfide) particles;
a countercurrent washing step comprising washing the separated poly(arylene sulfide) particles with at least one washing liquid selected from the group consisting of water, an organic solvent and a mixed solution of water and an organic solvent in a washing tower composed of a tower top portion, a body portion and a tower bottom portion,
wherein a poly(arylene sulfide) particle-containing aqueous slurry is introduced from an aqueous slurry supply port and caused to proceed downward in the washing tower, the washing liquid is introduced to the tower bottom portion and caused to proceed upward to continuously bring the washing liquid into countercurrent contact with the aqueous slurry in the body portion, thereby conducting countercurrent washing, the poly(arylene sulfide) particles are discharged from a polymer particle discharge port in the tower bottom portion, and a washing waste liquid is discharged from a washing waste liquid discharge port in the tower top portion,
wherein the body portion is divided into stirring chambers and the respective stirring chambers are mutually partitioned by partitioning plates, each plate having a center opening, wherein an agitating blade is arranged in each of the stirring chambers and the agitating blade is rotationally fixed to a common agitator shaft extending through the tower top portion and the body portion and is rotated in the stirring chamber, and
wherein the tower top portion has a flow path area sufficiently enlarged relative to the body portion such that the poly(arylene sulfide) particle-containing aqueous slurry introduced from the aqueous slurry supply port avoids axial backmixing by a liquid current discharged from the washing waste liquid discharge port;
a poly(arylene sulfide) particle re-separation step comprising supplying the washing waste liquid discharged from the washing waste liquid discharge port to a poly(arylene sulfide) particle re-separating unit including a micro-slit filter having slits of a size within a range of 30 to 200 μm, wherein the micro-slit filter captures poly(arylene sulfide) particles from the washing waste liquid, and then re-separating the captured poly(arylene sulfide) particles from the micro-slit filter by a periodic backwashing operation;
a collecting step of collecting the poly(arylene sulfide) particles separated from the micro-slit filter; and
a collecting step of collecting poly(arylene sulfide) particles discharged from the polymer particle discharge port.

2. The production process of the poly(arylene sulfide) according to claim 1 , wherein the countercurrent washing step is conducted plural times.

3. The production process of the poly(arylene sulfide) according to claim 1 , wherein the poly(arylene sulfide) particle-containing aqueous slurry contains an acidic compound.

4. The production process of the poly(arylene sulfide) according to claim 1 , wherein the polymerization step is a step of subjecting at least one sulfur source selected from the group consisting of the alkali metal sulfides and the alkali metal hydrosulfides and the dihalo-aromatic compound to a polymerization reaction at a temperature of 170 to 290° C. in the presence of a phase separation agent in the organic amide solvent.

5. The production process of the poly(arylene sulfide) according to claim 1 , wherein the polymerization step is a step of subjecting at least one sulfur source selected from the group consisting of the alkali metal sulfides and the alkali metal hydrosulfides and the dihalo-aromatic compound to a polymerization reaction at a temperature of 170 to 270° C. in the organic amide solvent, causing the phase separation agent to exist in a polymerization reaction system at the time a conversion of the dihalo-aromatic compound has reached at least 30% and continuing the polymerization reaction at a temperature of 245 to 290° C.

6. The production process of the poly(arylene sulfide) according to claim 1 , wherein the polymerization step is at least two-stage polymerization steps comprising a first-stage polymerization step of subjecting at least one sulfur source selected from the group consisting of the alkali metal sulfides and the alkali metal hydrosulfides and the dihalo-aromatic compound to a polymerization reaction in the organic amide solvent to form a polymer in which a conversion of the dihalo-aromatic compound is 80 to 99%; and
a second-stage polymerization step of continuing the polymerization reaction in the presence of the phase separation agent in a phase-separated state that a concentrated formed polymer phase and a dilute formed polymer phase are present in a mixed state within the polymerization reaction system.

7. The production process of the poly(arylene sulfide) according to claim 1 , wherein the polymerization step is at least two-stage polymerization steps comprising a first-stage polymerization step of subjecting at least one sulfur source selected from the group consisting of the alkali metal sulfides and the alkali metal hydrosulfides and the dihalo-aromatic compound to a polymerization reaction at a temperature of 170 to 270° C. in the organic amide solvent in a state that water is present in a proportion of 0.02 to 2.0 mol per mol of a charged sulfur source, thereby forming a polymer in which a conversion of the dihalo-aromatic compound is 80 to 99%; and
a second-stage polymerization step of controlling the amount of water in the polymerization reaction system so as to bring about a state that water exists in a proportion of from higher than 2.0 mol to not higher than 10 mol per mol of the charged sulfur source, and continuing the polymerization reaction at a temperature of 245 to 290° C. in a phase-separated state that a concentrated formed polymer phase and a dilute formed polymer phase are present in a mixed state within the polymerization reaction system.

8. The production process of the poly(arylene sulfide) according to claim 6 , wherein in the second-stage polymerization step, the amount of water in the polymerization reaction system is controlled so as to bring about a state that water exists in a proportion of from higher than 2.0 mol to not higher than 10 mol per mol of the charged sulfur source, and at least one phase separation agent selected from the group consisting of organic carboxylic acid metal salts, organic sulfonic acid metal salts, alkali metal halides, alkaline earth metal halides, aromatic carboxylic acid alkaline earth metal salts, phosphoric acid alkali metal salts, alcohols and paraffinic hydrocarbons is caused to exist within a range of 0.01 to 3 mol per mol of the charged sulfur source.

9. The production process of the poly(arylene sulfide) according to claim 1 , wherein prior to the polymerization step, are arranged
a dehydration step of heating and reacting a mixture containing the organic amide solvent, the sulfur source containing the alkali metal hydrosulfide and an alkali metal hydroxide in a proportion of 0.95 to 1.05 mol per mol of the alkali metal hydrosulfide to discharge at least a part of a distillate containing water from the interior of the system containing the mixture to the exterior of the system; and
a charging step of adding an alkali metal hydroxide and water to the mixture remaining in the system after th

Assignees

• Kimura Takayuki
• Koizumi Tomoyoshi
• Matsuzaki Mitsuhiro
• Kureha Corp

Inventors

• Kimura Takayuki
• Koizumi Tomoyoshi
• Matsuzaki Mitsuhiro

Classifications

• C08G75/0281

  Recovery or purification · CPC title

• C08G75/14 Primary

  Polysulfides · CPC title

• C08G75/0259 Primary

  metal hydrogensulfides · CPC title

• C08G75/02 Primary

  Polythioethers · CPC title

• B01J19/00

  Chemical, physical or physico-chemical processes in general; Their relevant apparatus · CPC title