EFFECT OF SOME SODIUM BISULFITE ADDUCTS OF DIFFERENT CHAIN LENGTHS ONTHE COURSE OF THE EMULSION POLYMERIZATION OF VINYL-ACETATE

The emulsion polymerization of vinyl acetate using some bisulfite addu cts of different chain lengths with potassium persulfate as the redox initiation system, in the absence of emulsifier, was studied. The effe cts of such adducts, which contain the same weight equivalent of bisul fite anion, on the rate of polymerization, maximum conversion, and sta bility of the produced polymer lattices as well as the morphological c haracteristics including volume-average diameters and the number of po lymer particles per unit volume of water were investigated. The rate o f polymerization was found to be dependent on the concentration of ben zaldehyde, acetaldehyde, octyl aldehyde, methyl propyl ketone, and ace tone sodium bisulfite adducts to the powers 0.54, 0.66, 0.95, 1.0, and 1.1, respectively. Also, it was found that increasing adduct chain le ngths decreases the volume-average diameter, increases the obtained la ttice stability, and improves the morphology of the polymeric particle s, where a spherical morphology and extra stability were obtained in t he presence of the octyl aldehyde adduct.