Claims
- 1. A process for improving the viscosity stability of an ethylene copolymer, being a copolymer of ethylene with at least one comonomer which is an ethylenically unsaturated carboxylic acid, said process consisting in exposing the solid, pelletized copolymer to moisture by exposing it to a purge gas heated to a temperature of at least 5.degree. C. above ambient and humidified to a relative humidity of at least 75%, for a sufficient period to cause the copolymer to retain at least 20 weight % more moisture than it would retain after purging it for 18 hours with air or nitrogen that has been heated to a temperature at least 5.degree. C. above ambient and has not been further humidified after being heated to a temperature of at least 5.degree. C. above ambient.
- 2. The process of claim 1 wherein the carboxylic acid comonomer in the ethylene copolymer is acrylic acid or methacrylic acid.
- 3. The process of claim 2 wherein the content of carboxylic acid comonomer in the ethylene copolymer is 5-20 weight percent.
- 4. The process of claim 1 wherein the copolymer is exposed to a purge gas selected from the group consisting of air and nitrogen.
Parent Case Info
This is a continuation of application Ser. No. 07/858,392 filed on Mar. 20, 1992, now abandoned.
US Referenced Citations (7)
Continuations (1)
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Number |
Date |
Country |
Parent |
858392 |
Mar 1992 |
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