Method of producing polyarylene sulfide

Patent metadata

Field	Value
Publication number	US-10501582-B2
Application number	US-201615759540-A
Country	US
Kind code	B2
Filing date	Sep 30, 2016
Priority date	Sep 30, 2015
Publication date	Dec 10, 2019
Grant date	Dec 10, 2019

Abstract

The present invention is to provide a method of producing polyarylene sulfide that can produce polyarylene sulfide having a low halogen content simply and easily and at low cost. The method of producing polyarylene sulfide according to an embodiment of the present invention includes: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, a dihalo aromatic compound, and an alkali metal hydroxide; a first-stage polymerization step of producing a prepolymer until a pH of a reaction system reaches a range of lower than 10 but 7 or higher by initiating a polymerization reaction by heating the mixture; and a second-stage polymerization step of continuing the polymerization reaction.

First claim

The invention claimed is:

1. A method of producing polyarylene sulfide that polymerizes a sulfur source and a dihalo aromatic compound in an organic amide solvent, the method comprising:
a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source,
a dihalo aromatic compound, and an alkali metal hydroxide;
a first-stage polymerization step of producing a prepolymer until a pH of a reaction system reaches a range of lower than 10 but 7 or higher by initiating a polymerization reaction by heating the mixture; and
a second-stage polymerization step of continuing the polymerization reaction,
wherein in the preparation step, the mixture containing from 0.7 to 0.9 mol of the alkali metal hydroxide per 1 mol of the sulfur source is prepared.

2. The method according to claim 1 , wherein
in the preparation step, a mixture containing the alkali metal hydroxide in an amount that is less than an equimolar amount per 1 mol of the sulfur source is prepared; and
in the second-stage polymerization step, the polymerization reaction is continued by adding from 0.01 to 0.6 mol of alkali metal hydroxide per 1 mol of the sulfur source.

3. The method according to claim 1 , wherein in the first-stage polymerization step, the prepolymer is produced until a conversion ratio of the dihalo aromatic compound reaches 50% or greater.

4. The method according to claim 1 , wherein the polymerization reaction is performed by heating the mixture prepared in the preparation step at a temperature of 170 to 270° C. in the first-stage polymerization step, and then the polymerization reaction is continued while heating at a temperature of 245 to 290° C. in the second-stage polymerization step.

5. The method according to claim 1 , wherein, in the second-stage polymerization step, the polymerization reaction is continued in a condition where the reaction system is phase-separated into a concentrated polymer phase and a dilute polymer phase in the presence of a phase separation agent.

6. The method according to claim 1 , wherein, in the first-stage polymerization step and the second-stage polymerization step, the polymerization reaction is performed in a homogeneous liquid phase condition.

7. The method according to claim 1 , wherein, in the first-stage polymerization step and/or the second-stage polymerization step, the polymerization reaction is performed in the presence of an end-capping agent.

Assignees

• Kureha Corp

Inventors

• Konno Akihiro
• Takaki Ken-Ichi
• Sato Hiroyuki

Classifications

• C08G75/0263 Primary

  using elemental sulfur · CPC title

• C08G75/0209

  derived from monomers containing one aromatic ring · CPC title

• C08K3/22

  of metals · CPC title

• C08G75/025 Primary

  Preparatory processes · CPC title

• C08G75/0204

  Polyarylenethioethers · CPC title