Synthesis of poly(vinyl alcohol)/poly(dimethylsiloxane) graft copolymer†

Poly(vinyl acetate)/poly(dimethylsiloxane) graft copolymer (4a), with a controlled poly(dimethylsiloxane) graft chain length, was synthesized by radical copolymerization of vinyl acetate with poly(dimethylsiloxane) (3) having a dimethylvinylsilyl end group. 3 was prepared by living anionic polymerization of hexamethylcyclotrisiloxane (1) with butyllithium and subsequent termination with chlorodimethylvinylsilane (2). Poly(vinyl alcohol)/poly(dimethylsiloxane) graft copolymer (4b) was then synthesized by selective saponification of the poly(vinyl acetate) segments in the graft copolymer 4a with K2CO3 in methanol.