Montell North America Inc.

Himont Incorporated

John W Mayfield

Anthony J DeNicola, Jr

B Joseph Scheve

Thomas F McLaughlin

James R Beren

Disclosed is a normally solid, high molecular weight, gel-free, amorphous to predominantly crystalline, propylene polymer characterized by high melt strength due to strain hardening which is believed to be caused by free-end long chain branches of the molecular chains forming the polymer. Also disclosed is a process for making the polymer by high energy radiation of a normally solid, high molecular weight, linear, propylene polymer in a reduced active oxygen environment, maintaining the irradiated material in such environment for a specific period of time, and then deactivating free radicals in the material. Further disclosed is the use of the strain hardening polymer in extensional flow operations such as, for example, extrusion coating, film production, and thermoforming.

High melt strength, propylene polymer, process for making it, and use

A normally solid, high molecular weight, gel-free, irradiated ethylene polymer is characterized by high melt strength due to strain hardening elongational viscosity, which is believed to be caused by free-end long chain branching of the molecular chains forming the polymer. The polymer is prepared by (1) irradiating a normally solid, high molecular weight ethylene polymer without strain hardening elongational viscosity while in the solid state in an environment in which the active oxygen concentration is less than 15% by volume, maintaining the irradiated material in this environment while in the solid state for a specific period of time, and then deactivating free radicals present in the material.

High melt strength, ethylene polymer, process for making it, and use

Disclosed is a normally solid, high molecular weight, gel-free, irradiated ethylene polymer having a density of from 0.89 to 0.97 g/cc characterized by high melt strength due to strain hardening which is believed to be caused by free-end long chain branches of the molecular chains forming the polymer. Also disclosed is a process for making the polymer by high energy radiation of a normally solid, high molecular weight, ethylene polymer in a reduced active oxygen environment, maintaining the irradiated material in such environment for a specific period of time, and then deactivating free radicals in the material.

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New Castle County, DE, United States of America

John W Mayfield