Dispersion Polymerization of Methyl Methacrylate using Poly(HDFDMA-co-MMA) as a Surfactant in Supercritical Carbon Dioxide

Abstract

New surfactants, random copolymers of heptadecafluorodecyl methacrylate (HDFDMA) and methyl methacrylate (MMA), were synthesized at 343.2 K and 30 MPa in supercritical carbon dioxide (scCO2) with varying HDFDMA/MMA ratios. 1H NMR and FT-IR were used to confirm the structure and to determine the composition of the resulting copolymers. The phase behavior of poly(HDFDMA-co-MMA) in CO2 was obtained by means of a variable volume view cell, which will be used to select the polymerization condition. After that, dispersion polymerization of methyl methacrylate (MMA) in scCO2 was performed using 2,2′-azobis(isobutyronitrile) (AIBN) as the initiator and poly(HDFDMA-co-MMA) with various MMA mole fraction as a surfactant. The new surfactant, poly(HDFDMA-co-MMA), whose MMA content is lower than 12.3 wt %, shows comparable capacity to produce PMMA particles compared to poly(HDFDMA) surfactant. The resulting PMMA particles, such as those produced using poly(HDFDMA) homopolymer as a surfactant, could also be produced with poly(HDFDMA-co-MMA) up to 12.3 wt % MMA.