ABSTRACT Polymerization was carried out with surfactant-styrene-brine systems which were formulated for the attainement of ultra-low interfacial tension and three-phase behavior. An anionic-nonionic surfactant mixture was used to maintain the optimum formulation over a certain range of temperature. Dispersion polymerization experiments were carried out with the initiator either in water (persulfate) or in styrene (AIBN). The polymerization systems exhibited both rate of polymerization and molecular weight dependence on the amount of added initiator, but no autoacceleration was observed.