Polymerisation of styrene emulsified by phase inversion in the presence of polyisobutene

An attempt has been made to synthesise water-borne polymer composites using a new method. Polyisobutene was dissolved in styrene and an emulsion was formed by phase inversion. Polystyrene was then generated in the drops by polymerisation of the styrene using an oil-soluble initiator. The effects of changes in the polyisobutene concentration, the initiator concentration, the surfactant concentration and the oil–water ratio on the polymerisation system were investigated. The polymerisation rate increased with increasing initiator concentration, decreasing polyisobutene concentration, increasing surfactant concentration and increasing water to oil ratio. The average particle size decreased gradually during the polymerisation. The final average particle size decreased with increasing the concentration of surfactant. However, the ratio of water to oil, the initiator concentration and the polyisobutene concentration had little effect on the final latex particles size. Although, oil drops were transformed into composite particles, new polystyrene particles were also generated in the aqueous phase.