Thermal terpolymerization of alphamethylstyrene, acrylonitrile and styrene

The ceiling temperature constraint encountered in the homopolymerization of alphamethylstyrene, AMS, can be circumvented by copolymerization with acry lonitrile to prepare multicomponent random microstructures that offer highe r heat resistance than SAN. The feasibility of a thermal initiation of free radical chain polymerization is evaluated by the study of the terpolymeriz ation kinetics of AMS-AN-Styrene. Process considerations such as polyrates, molecular weight of the copolymer formed, sensitivity of molecular weight, molecular weight distribution and kinetics to temperature are measured. Th e range of weight fractions of monomers of styrene, acrylonitrile and alpha methylstyrene varied in the study are f(sty) = 0.1-0.45, f(an) = 0.1-0.4, f (ams) = 0.2-0.75, respectively. Empirical correlations are provided for the polyrate, weight average molecular weight, M-w, in the temperature range 3 98-418 K. (C) 1999 Elsevier Science Ltd. All rights reserved.