Patent · US Expired

Process for chain stopping of PVC polymerization

US7683144B2 · kind B2 · utility

0Cited by

10References

12Claims

0Family size

Assignee

Ciba Specialty Chemicals Corporation · US

Inventors

Rudolf Pfaendner · Rimbach, DE
Alex Wegmann · Allschwil, CH
Thomas Wannemacher · Taufkirchen, DE
Dietrich Braun · Darmstadt, DE

Key dates

Filing date	Apr 24, 2003
Grant date	Mar 23, 2010
Priority date	—
Expiry date	Jul 7, 2024

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08F2438/02
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

The present invention relates to a process and composition for the chain stopping of vinyl chloride polymerization or copolymerization in the presence of a stable free nitroxyl radical and a phenolic antioxidant. A further subject of the invention is the use of a stable free nitroxyl radical together with a phenolic antioxidant as a chain stopping mixture for the vinyl chloride polymerization or copolymerization. A further aspect of the invention is the use of higher sterically hindered nitroxyl radicals alone as chain stopping agents for the vinyl chloride polymerization.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.