LIVING ATOM-TRANSFER RADICAL POLYMERIZATION OF 4-ACETOXYSTYRENE

Living atom transfer radical polymerization (ATRP) of 4-acetoxystyrene (1), a protected 4-vinylphenol, leading to poly(4-acetoxystyrene) wit h well-defined molecular weight and narrow molecular weight distributi on was carried out in bulk with a,a'-dibromoxylene(2)/CuBr/2,2-bipyrid ine(bpy) as initiating system. A linear (M) over bar(n), versus monome r conversion plot was found in good accordance with the theoretical li ne, indicating 100% initiating efficiency. The polymerization is first order in respect to monomer up to about 70% monomer conversion. Devia tions from linearity at higher conversion in the first order plot are due to physical effects, i.e., to the increase of the viscosity of the reaction medium. The resulting 1-bromo-1-phenylethyl-telechelic poly( 4-acetoxystyrene) (3) is a precursor of the hydrophilic poly(4-vinylph enol) and a potential new macroinitiator.