SYNTHESIS OF POLY(ETHYLENE OXIDE) MACROINITIATORS WITH A VIEW TO THE PREPARATION OF BLOCK COPOLYMERS BY RADICAL POLYMERIZATION

Poly(ethylene oxide) radical macroinitiators with built-in benzopinaco late groups were prepared by two different methods: the first one invo lves a hydrosilylation reaction between-alpha, omega-difunctional poly ethylene oxide (PEO) precursors and a difunctional benzopinacolate; du e to the presence of a spacer group on the benzopinacolate compound th e resulting segmented PEO is rather close to a block-copolymer. The se cond method is based on the general duplication reaction of benzopheno ne groups fitted at both chain ends of a PEO precursor.