Synthesis and Phase Behavior of CO₂-Soluble Hydrocarbon Copolymer: Poly(vinyl acetate-<i>alt</i>-dibutyl maleate)

Abstract

We report the synthesis of a new hydrocarbon copolymer which is soluble in supercritical carbon dioxide. Poly(vinyl acetate-alt-dibutyl maleate) (PVAc-alt-PDBM) copolymer was synthesized by free-radical polymerization mediated by the RAFT technique. Liquid CO2 extraction was performed to remove the residual monomer and solvent from the final product. The solubility of the copolymers was measured in a variable volume view cell at temperatures between 25 and 75 °C. The phase behavior of the copolymer in CO2 was studied in terms of its molecular weight and concentration in the solvent. It was found that the copolymer shows good solubility in CO2 approaching that of perfluoropolyether (PFPE) and poly(dimethylsiloxane) monomethacrylate (PDMS-mMA).