MACROMONOMERS BY ACTIVATED POLYMERIZATION OF OXIRANES - SYNTHESIS ANDPOLYMERIZATION

Macromonomers were obtained by cationic polymerization of propylene ox ide and epichlorohydrin proceeding by the activated monomer mechanism with hydroxyethyl acrylate as initiator. Up to DPn similar to 15 for p ropylene oxide and DPn similar to 20 for epichlorohydrin, polymerizati on proceeds as a living process, giving with quantitative yields macro monomers with functionality equal to one, controlled molecular weight and narrow molecular weight distribution ((M) over bar(w)/(M) over bar (n) < 1.2) free of side products. In the higher molecular weight regio n, side reactions become increasingly noticeable. Propylene oxide macr omonomers undergo radical homopolymerization. Homopolymerization of ma cromonomer with (M) over bar(n) = 8 x 10(2) gives graft copolymers wit h (M) over bar(n) up to 7.2 x 10(3). In copolymerization with styrene, completely soluble graft copolymers with (M) over bar(n) similar to 2 x 10(4) were obtained. Radical copolymerization of epichlorohydrin ma cromonomers with styrene gives initially soluble products with (M) ove r bar(n) similar to 6 x 10(4) which are converted in the later stages into insoluble gels, apparently due to the chain transfer to chloromet hyl groups of the polyepichlorohydrin chains.