Stabilized polychloroethylenes
AssigneePPG Industries Ohio, Inc.
InventorsEarl M. Gorton, Ronald D. Olinger
Life of this patent
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Abstract
Polychloroethylene, e.g., trichioroethylene and perchloroethylene, is stabilized with a stabilizing amount of a stable free radical stabilizer, e.g., a material having the 2,2,6,6-tetra(lower alkyl)-1-piperidinyloxy-yl free radical group, such as 2,2,6,6-tetramethyl-4-hydroxy-1-piperidinyloxy, or the 2,2,5,5-tetra(lower alkyl)pyrrolidinyloxy group, such as 2,2,5,5-tetramethyl pyrrolidinyloxy. Stable free radical stabilizer is removed from a polychloroethylene composition containing same by contacting the composition with silica, e.g., precipitated silica.
Claims18
A method for removing stable free radical stabilizer from a liquid composition comprising polychloroethylene and a minor amount of stable free radical stabilizer, comprising contacting said liquid composition with an amount of silica sufficient to adsorb stable free radical stabilizer and provide a polychloroethylene composition substantially free of stable free radical stabilizer.
A composition comprising polychloroethylene chosen from trichloroethylene and perchloroethylene and a stabilizing amount of stable free radical stabilizer having the 2,2,5,5-tetra(lower alkyl)pyrrolidinyloxy group.
A method for removing stable free radical stabilizer from a liquid composition comprising polychloroethylene and less than 50 ppm of stable free radical stabilizer having the 2,2,6,6-tetra(lower alkyl)-1-piperidinyloxy-yl free radical group, comprising treating said liquid composition with an amount of precipitated silica sufficient to adsorb stable free radical stabilizer and provide a polychloroethylene composition substantially free of stable free radical stabilizer.
Dependencies are inferred from the claim text.