SELECTIVE ADSORPTION OF POLYMER ON FRESHLY GROUND SOLID-SURFACES IN SOAPLESS EMULSION POLYMERIZATION

Soapless emulsion polymerization of methyl methacrylate initiated by a redox system of sodium bisulfite and oxygen in water in the presence of limestone was carried out by grinding the limestone in a vibrating ball mill reactor. The effect of a fresh solid surface produced on the adhesion between the solid and polymer formed was investigated. Examination of the resulting composite powder by scanning electron microscope indicated that the polymer selectively adsorbed on sites of the simultaneously ground limestone, whereas nonselective adsorption was observed on the previously ground limestone.