# US 5,352,768 A · Acid treatment of poly(arylene sulfide) polymer reaction mixture

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- Number: US 5,352,768 A
- Document ID: US5352768A
- Status: Granted
- Kind: A
- Application number: 07/965,644
- Filed: 1992-10-23
- Granted: 1994-10-04
- Earliest claimed: 1992-10-23
- Assignees: Phillips Petroleum Company
- Inventors: John D. Stuber; Wei-Teh W. Shang; Lacey E. Scoggins
- Web page: https://patentgrep.com/patent/US5352768A

## CPC

- C08G 75/025: Preparatory processes
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS

## Abstract

A method is provided for producing a poly(arylene sulfide) polymer having reduced amounts of impurities by contacting a poly(arylene sulfide) polymerization reaction mixture with an acid.

## Claims

### Claim 1

A process for producing a poly(arylene sulfide) polymer which comprises
contacting reactants comprising at least one sulfur source, at least one dihaloaromatic compound and a polar organic compound to form a polymerization reaction mixture,
subjecting said polymerization reaction mixture to suitable polymerization conditions to form said poly(arylene sulfide) polymer,
contacting said reaction mixture with an acidic solution while maintaining said suitable polymerization conditions, and thereafter
recovering said poly(arylene sulfide) polymer.

### Claim 2 (depends on 1)

A process according to claim 1 wherein said suitable conditions comprise a polymerization reaction temperature in the range of about 235.degree. to about 450.degree. C.

### Claim 3 (depends on 1)

A process in accordance with claim 1 wherein the amount of acidic solution employed is in the range of about 0.025 mol to about 0.100 mol, based on 1 mole poly(arylene sulfide).

### Claim 4 (depends on 3)

A process in accordance with claim 3 wherein said acidic solution is an acetic acid solution.

### Claim 5 (depends on 1)

A process in accordance with claim 1 wherein said poly(arylene sulfide) polymer is poly(phenylene sulfide).

### Claim 6 (depends on 1)

A process in accordance with claim 1 wherein said acidic solution and said reaction mixture are contacted for a time period at least sufficient to disperse the acidic solution in reaction mixture.

### Claim 7 (depends on 1)

A process in accordance with claim 1 wherein said reaction mixture is subjected to said suitable conditions for a time period in the range of 10 mins. to 3 days.

### Claim 8 (depends on 7)

A process in accordance with claim 7 wherein said acidic solution is contacted with said reaction mixture during the time period in the range of 5 minutes up to about 45 minutes prior to recovery of said poly(arylene sulfide) polymer.

### Claim 9

A process for preparing a poly(phenylene sulfide) polymer which comprises
contacting reactants comprising dichlorobenzene, sodium sulfide, sodium hydroxide, N-methyl-2-pyrrolidone to form a polymerization reaction mixture,
subjecting said polymerization reaction mixture to polymerization conditions of temperature in the range of about 235.degree. C. to about 450.degree. C. and time in the range of about 1 hour to 8 hours,
contacting said reaction mixture with an acidic solution while maintaining said polymerization conditions, and thereafter
recovering said poly(phenylene sulfide) polymer.

### Claim 10 (depends on 9)

A process according to claim 9 wherein said acidic solution is an acetic acid solution.