# US 4,391,950 A · Polyphenylene ether composition and process for production

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- Number: US 4,391,950 A
- Document ID: US4391950A
- Status: Granted
- Kind: A
- Application number: 06/298,534
- Filed: 1981-09-02
- Granted: 1983-07-05
- Earliest claimed: 1981-09-02
- Assignees: General Electric Company
- Inventors: Glenn D. Cooper
- Web page: https://patentgrep.com/patent/US4391950A

## CPC

- C08G 65/485: {Polyphenylene oxides}
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS

## Abstract

An improved polyphenylene ether composition and process for production are disclosed. Benzoic anhydride is reacted with polyphenylene ether polymer, preferably under conditions of extrusion, to produce a composition having improved color and/or color stability.

## Claims

### Claim 1

A thermoplastic composition having improved color properties, comprising the reaction product of polyphenylene ether with a minor amount of benzoic anhydride sufficient to improve the color or the color stability.

### Claim 2 (depends on 1)

The composition of claim 1, wherein the concentration of benzoic anhydride is from 0.05 to 5% by weight of polyphenylene ether.

### Claim 3 (depends on 2)

The composition of claim 2, wherein an admixture of polyphenylene ether and benzoic anhydride is subjected to treatment at a temperature of from 200.degree. to 500.degree. C. to produce the reaction product.

### Claim 4 (depends on 3)

The composition of claim 3, wherein the treatment is performed by extruding the admixture.

### Claim 5 (depends on 1)

The composition of claim 1, wherein the composition additionally contains from 1 to 99% of polyalkenyl aromatic resin by total weight.

### Claim 6 (depends on 5)

The composition of claim 5, wherein the polyphenylene ether of the admixture is a decolorized polymer.

### Claim 7 (depends on 6)

The composition of claim 6, wherein the polymer is obtained from a polymerization medium by a total isolation process.

### Claim 8 (depends on 1)

A process for producing the composition of claim 1, comprising admixing polyphenylene ether with from 0.05 to 5% by weight of benzoic anhydride and subjecting said admixture to treatment at a temperature of from 200.degree. to 500.degree. C. to effect a color stabilizing reaction.

### Claim 9 (depends on 8)

The process of claim 8, wherein the treatment is performed by extruding the admixture.

### Claim 10 (depends on 9)

The process of claim 9, wherein the polyphenylene ether of the admixture is a decolorized polymer.

### Claim 11 (depends on 10)

The process of claim 10, wherein decolorization is performed by catalytic hydrogenation.

### Claim 12 (depends on 10)

The process of claim 10, wherein decolorization is performed by adsorption.

### Claim 13 (depends on 10)

The process of claim 10, wherein the polymer is isolated from a polymerization medium by steam precipitation prior to admixing.

### Claim 14 (depends on 10)

The process of claim 10, wherein the polymer is isolated from a polymerization medium by addition to hot water prior to admixing.

### Claim 15 (depends on 11)

The process of claim 11, wherein the admixture is extruded with from 1 to 99% of polyalkenyl aromatic resin by total weight.

### Claim 16

A thermoplastic composition characterized by improved color properties, comprising the reaction product of polyphenylene ether with from 0.05 to 5% by weight of benzoic anhydride.