TRIBLOCK COPOLYMERS VIA MACRO-INIFERTERS - BLOCK-COPOLYMERS OF EPICHLORHYDRIN WITH STYRENE AND METHYL-METHACRYLATE

A route for preparing block copolymers by the combination of cationic and free radical photopolymerization is examined. For this purpose, a growing polyepichlorhydrin (PECH) chain, prepared by using HBF4 as an initiator, was terminated by the addition of the sodium salt of N,N-di ethyl dithiocarbamate. PECH possessing a thiuram disulfide group at th e chain end thus obtained was used in the photo-induced polymerization of styrene to yield active poly(epichlorhydrin-b-styrene) block copol ymers. These active block copolymers were also used in the photopolyme rization of methyl methacrylate to obtain ABC-type triblock copolymers . The block copolymers were characterized by spectroscopic methods, fr actional precipitation, and gel permeation chromatography.