EMULSION POLYMERIZATION OF VINYL-ACETATE AND STYRENE MONOMERS IN PRESENCE OF POLYMERIC SURFACTANT

Polymeric surfactant was prepared from polyoxyethylene methylether (PO E, 66 wt%) and styrene (St, 34 wt%) in the presence of benzoyl peroxid e as initiator using a macroradical polymerization technique. Fourier Transform Infrared Spectroscopy (FTIR) and (HNMR)-H-1 were used to con firm the formation of graft copolymer. The cloud point for the obtaine d graft copolymer was found to be 75 degrees C. The stabilizing effici ency of this nonionic copolymer as surfactant was tested in the emulsi on polymerization of vinyl acetate and styrene monomers in the presenc e of potassium persulfate (K2S2O8) as initiator. The rate of polymeriz ation was found to be proportional to the 0.9th and 0.76th power of in itiator concentrations, and to the 0.77th and 0.66th power of the surf actant concentrations for vinyl acetate and styrene monomers, respecti vely. The apparent activation energies were found to be 69.13 and 50.2 7 kJ/mol for emulsion polymerization of vinyl acetate and styrene, res pectively.