Hydrolysis of 4-acetoxystyrene polymers prepared by atom transfer radical polymerization

Hydrolysis of 4-acetoxystyrene polymers prepared by atom transfer radical p olymerization was carried out under various reaction conditions. It was fou nd that hydrazinolysis of 4-acetoxystyrene homopolymers, random and block c opolymers with styrene in 1,4-dioxane, afforded the corresponding narrow di spersed materials with phenolic groups which were substantially free from c rosslinkages. Gel permeation chromatographic (GPC) analysis of these polyme rs revealed different extents of molecular weight distribution (MWD) broade ning for the hydrolysis products for the different structures. On the other hand, by NaOH catalyzed deprotection, the 4-acetoxystyrene polymers includ ing triblock copolymer poly(4-acetoxystyrene-b-isobutylene-b-4-toxystyrene) suffered from some degrees of coupling or even gelation, except for poly(s tyrene-b-4-acetoxystyrene-b-styrene) which also by this method could be con veniently converted to its phenolic product. (C) 1999 John Wiley & Sons, In c.