PREPARATION OF POLY(VINYL CHLORIDE) LATEXES BY POLYMERIZATION OF STABILIZED MONOMER DROPLETS

Poly(vinyl chloride) latexes have been prepared by polymerization in m icron and submicron sized monomer droplets. Monomer emulsions with exc ellent long time stability were obtained by diffusional swelling of vi nyl chloride monomer into preformed, stable polydisperse pre-emulsions of water-insoluble oils or monodisperse, oligomer styrene seed partic les. It was found that the size and size distribution of the final lat ex particles were determined by those of the parent monomer emulsions. Except for the secondary particles formed during polymerization, the size and size distributions of the latex particles were found to be co mparable to those of the monomer emulsions employed, indicating a comp lete nucleation of the parent emulsion droplets. The extent of seconda ry particle formation was found to be very dependent upon the emulsifi er concentration as well as on the type and amount of initiator used. (C) 1995 John Wiley & Sons, Inc.