Disclosed herein are acrylic emulsions with more than one micron size polymer particles, and methods of synthesizing and using the emulsion compositions.

The present invention relates to a method comprising the steps of: a) contacting styrene and an ethylenically unsaturated monomer under emulsion polymerization conditions to form an aqueous dispersion of styrenic copolymer particles and residual monomers; and b) contacting the dispersion of the styrenic copolymer particles with a reductant and a t-C.sub.4-C.sub.10-alkyl hydroperoxide to reduce the concentration of residual monomers in the aqueous dispersion to less than 1000 ppm of residual monomers; wherein the mole-to-mole ratio of the t-C.sub.4-C.sub.10-alkyl hydroperoxide to reductant is in the range of from 3:1 to 50:1. The method of the present invention provides a way of preserving a styrenic latex even in the absence of a biocide.

Treaters that are configured to remove one or more contaminants from hydrocarbon streams recovered from a polymerization process are located upstream of the monomer and diluent recovery unit.