Patent ID: 7935740

Claim:
A process comprising: irradiating an extrudate comprising a propylene polymer composition with about 1 to about 20 Megarad of radiation to form an irradiated extrudate; the propylene polymer composition being irradiated in a reduced oxygen environment, wherein active oxygen is in an established and maintained concentration of less than about 15% by volume, with respect to a total volume of the reduced oxygen environment; maintaining the irradiated extrudate in the reduced oxygen environment for a period of time sufficient for a significant amount of long chain branches to form within the irradiated extrudate; and treating the irradiated extrudate while the irradiated extrudate is in the reduced oxygen environment to substantially deactivate free radicals present in the irradiated extrudate, wherein the propylene polymer composition comprises: (A) a propylene polymer having a polydispersity index between 2.1 and 3.4; and (B) 0.001 to 1 pph of a non-phenolic stabilizer selected from hindered amines, hydroxylamines, nitrones, amine oxides, benzofuranones, organic phosphites, phosphonites or mixtures thereof, based on the weight of the propylene polymer.