Free radical polymerizations of ol-methylstyrene (AMS) were performed in dispersions of oil in water using a mixture of nonionic nonylphenoxy poly(ethylene glycol) surfactants and initiated with ascorbic acid/hydrogen peroxide at temperatures ranging from 3 to 45 degreesC. A bimodal distribution of high (similar to 60,000 g/mol) and low molecular weight components (similar to 8000 g/mol) was analyzed by size-exclusion chromatography (SEC). The relative amount of the low molecular weight fraction increased with increasing the polymerization temperature. The polymer yields decreased from 52% at 3 degreesC to 3% at 45 degreesC. The syndiotactic content of PAMS decreased from 70% rr at 3 degreesC to 58% rr at 45 degreesC. (C) 2001 John Wiley & Sons, Inc.