Dispersion Polymerization of Styrene in Supercritical Carbon Dioxide: Importance of Effective Surfactants

Abstract

The dispersion polymerization of styrene in supercritical CO2 using amphiphilic diblock copolymers to impart steric stabilization was investigated. Lipophilic, CO2-insoluble materials can be effectively emulsified in carbon dioxide using amphiphilic diblock copolymer surfactants. The resulting high yield (>90%) of polystyrene is obtained in the form of a stable polymer colloid comprised of submicron-sized particles. The particle diameter and distribution of sizes were shown to be dependent on the nature of the stabilizing block copolymer.