Graft copolymerization of end allenoxy polyoxyethylene macromonomer onto ethyl cellulose in a homogeneous system

Abstract The homogeneous grafting of end-allenoxy polyoxyethylene macromonomers ( M n =390; PEGA39) onto ethyl cellulose (EC) was carried out using α – α ′-azobisisobutyronitrile (AIBN) as free radical initiator in benzene as solvent. The grafting percentage, grafting efficiency and weight conversion were determined as a function of polymerization temperature, and the concentration of PEGA39, EC and initiator. The graft copolymers were characterized by infrared spectroscopy and intrinsic viscosity measurements. The observed low grafting efficiency of PEGA39 macromonomer onto EC are attributed to steric or excluded volume effect, involving repulsion between the growing chain and that of macromonomer and EC chains. The mechanism of the grafting reaction was proposed.