New comblike copolymers of controlled structure and dimensions obtained by grafting polystyryllithium onto poly(chloroethyl vinyl ether) chains

The grafting reaction of polystyrene branches onto poly(chloroethyl vinyl ether) (PCEVE) chains, based on the deactivation of polystyryl (PS) carbanionic ends onto chloroethyl ether functions has been investigated. The selectivity of the coupling is very high and allows the almost complete substitution of the chloride group of the CEVE units by PS chains with molar masses up to 15000. The main side reaction observed is the deactivation of some PS chains, at the very beginning of the reaction. It is attributed mainly to impurities present in the PCEVE solution. Since the PCEVE polymer backbone and the PS grafts can be prepared by both living cationic and anionic polymerization, it is possible to synthesize poly(CEVE-g-styrene) copolymers possessing both a backbone with controlled dimensions and an adjustable number of branches having precise length and narrow molar mass distribution. The synthesis and the characteristics of comblike poly[(chloroethyl vinyl ether)-g-styrene]s are described.