Effect of modification of poly(vinyl alcohol) on ability of protective colloid in emulsion polymerization

Modification of poly(vinyl alcohol) (PVA) with an n-dodecyl end group improved the ability of the protective colloid in emulsion polymerization of styrene and butyl acrylate to some extent, while the emulsion polymerizations of the monomers did not proceed satisfactorily in the presence of ordinary PVA. Introduction of anionic group to the side chain of the PVA with an n-dodecyl end group also improved the ability in the emulsion polymerization of styrene to a great extent, yielding the emulsion without any characteristics of PVA system. PVA with a reactive thiol group at one end facilitated the emulsion polymerization of the monomers. The emulsions with characteristics of PVA medium appeared to be caused by block-copolymerization.