New oxidants for initiation of emulsion polymerization in antifreeze recipes at −10°C.

Abstract

Abstract The introduction of the Dioxes as oxidants in emulsion polymerizations at subfreezing temperatures has opened up new horizons especially in the direction of the utilization of commercially available rosin acid soaps in formulations containing low iron concentrations. It is now possible to copolymerize butadiene and styrene to 60% conversion in 16 hours in an emulsion recipe containing only 0.3 millimole of iron per 100 g. of monomers with Diox * D, Dresinate 214, and potassium soap flakes; formerly it had been impossible to reach such a conversion within 24 hours. By the use of mixed potassium laurate‐ myristate emulsifier and Diox 7, a conversion of 60% with a fluid latex was achieved in 119 hours at −10°C. In order to attain these high rates of conversion, it is necessary that the redox components of the polymerization recipe be properly “balanced” with respect to the mole ratio of oxidant to iron, and that the potassium chloride concentration in the activator and the p H of the emulsifier solution be adjusted to their optimum values.