Super-enhanced particle nucleation in styrene emulsion polymerization in the presence of sodium styrene sulfonate

J Colloid Interface Sci. 2017 Aug 15:500:126-132. doi: 10.1016/j.jcis.2017.04.015. Epub 2017 Apr 7.

Abstract

The styrene (St) emulsion polymerization using Aerosol MA80 as surfactant and in the presence of sodium styrene sulfonate (NaSS) was studied. The effect of NaSS content was assessed using MA80 concentrations below and at the critical micellar concentration. It was found that at the higher NaSS and MA80 contents, the number of particles (N) reaches a maximum of the order of 1017particles/cm3 water, a huge value that has never been reported. In this work an explanation for this super-enhanced particle nucleation phenomenon is proposed. Such hypothesis is based on the role of St-NaSS oligomers formed in the aqueous phase and their synergy with MA80 molecules to provide colloidal stability to the system. The proposal seems to be consistent with the experimental data obtained for the evolution of monomer conversion, N, particles size distribution and the wideness of this latter as well as with a theoretical estimation of the N.

Keywords: Aerosol MA80; Emulsion polymerization; Sodium styrene sulfonate; Styrene; Super-enhanced particle nucleation.