Synthesis and fundamental structural analysis of composite PVC latices

Syntheses of various combinations of composite particles were carried out employing PVC‐based latices, PVC, PVC–VAc and PVC–VD, as seed particles. Monomers for seed polymerization were chosen so that the solubility in water and the compatibility with seed polymer may influence the features of products. MMA, whose coverage improves the flow characteristics of PVC plastisols to a great extent, was most investigated along with MMA‐ST, BMA, and ST. Smaller monomerpolymer feed ratio (M/P), smaller seed size, and the employment of monomers sparsely soluble in water were the key factors in preventing the nucleation of secondary particles during the seed polymerization. A quantitative correlation to evaluate how effectively monomer is converted for the formation of composite particles was proposed. Analyses by means of the electron microscopy (TEM and SEM), GPC, DSC, and TLC strongly anticipated the development of IPN structure and the formation of graft linkage between PVC–VAc core and PMMA.