Journal of the American Chemical Society, Vol.134, No.29, 11920-11923, 2012
Enhancement of Poly(vinyl ester) Solubility in Supercritical CO2 by Partial Fluorination: The Key Role of Polymer-Polymer Interactions
An enhancement of poly(vinyl ester) solubility in supercritical carbon dioxide (sc-CO2) can be achieved by decreasing the strength of the polymer-polymer interactions. To demonstrate this, a library of statistical copolymers of vinyl acetate and vinyl trifluoroacetate was synthesized by RAFT/MADIX polymerization with varying compositions at a given number average molecular weight. These copolymers exhibited unprecedentedly low cloud point pressures in sc-CO2 at 40 degrees C compared with previously reported poly(vinyl esters). Surface tension measurements combined with a computational approach evidenced the prominent role played by polymer-polymer interactions.