Patent ID: 9127144
Filing Date: 2015-09-08
Classification: C08K

Abstract:
1. A stabilized polyolefin composition for film or fiber formation prepared by processing a mixture comprising a polyolefin and antioxidant composition at temperatures above the melting point of the polyolefin, wherein the antioxidant composition comprises a combination of hindered phenol and liquid phosphite in a weight ratio of hindered phenol to phosphite of about 1:1 to about 1:10 and is present in said mixture before processing at a concentration of from about 0.01 wt % to about 8 wt %, based on the combined weight of polyolefin plus antioxidant composition, and wherein after processing at temperatures above the melting point of the polyolefin the stabilized polyolefin composition comprises greater than 30% retained active phosphorus based on the active phosphorus of the mixture comprising the polyolefin and antioxidant composition prior to processing, wherein said phenol is selected from the group consisting of compounds of formula I and said liquid phosphite comprises a mixture consisting of: from 0 to 20 weight percent based on the total weight of phosphite of a tris(diamylphenyl)phosphite or tris(dibutylphenyl)phosphite; from 20 to 75 weight percent based on the total weight of the phosphite of a tris(monoamylphenyl)phosphite or tris(monobutylphenyl)phosphite; from 2 to 20 weight percent based on the total weight of the phosphite of a bis(diamylphenyl)monoamylphenyl phosphite or a bis(dibutylphenyl)monobutylphenyl phosphite; and from 15 to 60 weight percent based on the total weight of the phosphite of a bis(monoamylphenyl)diamylphenyl phosphite or a bis(monobutylphenyl)dibutylphenyl phosphite, which liquid phosphite makes up at least 90% by weight of all phosphites present in the composition before processing.