Binary mixtures of anionic double-chain sulfonate emulsifiers in VCM emulsion polymerization with high solid content: effect of emulsifier's combination ratio and concentration

Binary mixtures of anionic double-chain sulfonate emulsifiers, sodium di-isodecyl sulfosuccinate and sodium pentadecan-sulfonate (SPS) were employed in batch reactor at different combination ratios and concentration for vinyl chloride emulsion polymerization. Reaction performances were evaluated by monitoring conversion rate and molecular weight by K-value parameter. Particle size and its distribution were investigated as a criterion for particle nucleation and the growing process by calculating the number of latex particles and the average number of growing chains per particle, respectively. The final latexes were evaluated by means of the coarse matter content as a qualitative character of the latex. The results showed that the overall reaction rate increases by high amount of SPS. Also, by increasing SPS content in binary mixture, coarse particle formation decreased and latex stability and particle size distribution increased. Furthermore, it has been found that the particle size was nonlinearly dependent on the combined ratio and amount of emulsifier and has shown a minimum within the scope of the study.