Unusual Free Radical Polymerization of Vinyl Acetate in Anionic Microemulsion Media

This is the authors' abstract. We don't add key points for this paper.

The polymerization of vinyl acetate in one-phase o/w microemulsions stabilized with Aerosol OT (AOT) is examined as a function of concentration and type of initiator (V-50 and KPS) and temperature. Conversions and reaction rates increase with increasing concentration of V-50 and temperature. Faster polymerization rates and higher conversions are achieved with KPS because of the different electrostatic interactions between the charged microemulsion droplets and the free radicals of KPS and V-50. Average molar masses and polydispersity indexes ( M̄ w / M̄ n ) are much smaller than those observed in emulsion polymerization using the same surfactant, even at high conversions. Analysis of the molar mass distribution indicates that chain-transfer reactions to monomer are the controlling chain-growth mechanism in the polymerization of vinyl acetate in AOT microemulsions at all conversions.