Poly(vinyl chloride) polymerization performance‐enhancing initiators with emphasis on high activity grades and water‐based dispersions

Abstract

Abstract Vinyl chloride is most commonly polymerized by suspension processes, where surface active materials as granulating agents and organic peroxides as free radical initiators are the crucial additives, which may affect PVC qualities substantially. Among the wide variety of usable and commercially available organic peroxides, the most suitable types for an individual process need to be selected with specific regard to reactivity, polymerization performance, storage, and handling. Currently, high activity types are subject of continuously growing interest to many PVC manufacturers who are trying to achieve higher productivity and to expand their product range mainly by focusing on PVC grades of higher molecular mass. A short comparison between the different alternatives of highly active initiators is given, showing the potential for further improvement by using a new difunctional peroxyneodecanoate. Among the manifold formulations of organic peroxides, which have been developed, particular importance is attached to water‐based grades. Dispersions of solid peroxydicarbonates are explained in detail, and their outstanding benefits on performance and safety are covered.