Enhancement of Poly(vinyl ester) Solubility in Supercritical CO_2 by Partial Fluorination: The Key Role of Polymer-Polymer Interactions

摘要

An enhancement of poly (vinyl ester) solubility in supercritical carbon dioxide (sc-CO_2) 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 trifluor-oacetate 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-CO_2 at 40 ℃ compared with previously reported poly(vinyl esters). Surface tension measurements combined with a computational approach evidenced the prominent role played by polymer-polymer interactions.