Phase behavior measurement for poly(isobornyl acrylate) + cosolvent systems in supercritical solvents at high pressure

Abstract

We have conducted experiments to obtain cloud-point data of binary and ternary mixtures for poly(isobornyl acrylate) [P(IBnA)] (Mw=100,000)+isobornyl acrylate(IBnA) in supercritical carbon dioxide (CO2), P(IBnA) (Mw=100,000)+dimethyl ether (DME) in CO2, P(IBnA) (Mw=100,000) in propane and butane, and P(IBnA) (Mw=1,000,000) in propane, propylene, butane and 1-butene at high pressure conditions. Phase behaviors for these systems were measured at a temperature range from 323.4K to 474.1K and pressure up to 296.7MPa. The cloud-point curves of P(IBnA) (Mw=100,000)+IBnA and DME in CO2 change from upper critical solution temperature (UCST) behavior to lower critical solution temperature (LCST) behavior as IBnA and DME concentration increases, and liquid–liquid–vapor phase behavior appears for the P(IBnA) (Mw=100,000)+CO2+80.3wt.% IBnA system. Phase behaviors of P(IBnA) and 50wt.% IBnA in CO2 and P(IBnA) in propane and butane show the pressure difference in accordance with Mw=1,000,000 and Mw=100,000 of P(IBnA). Also, the solubility curves for IBnA in supercritical CO2 were measured at a temperature range of (313.2–393.2)K and pressure up to 22.86MPa. The experimental results were modeled with the Peng–Robinson equation of state (PR-EOS) using a mixing rule including two adjustable parameters. The critical property of IBnA is estimated with the Joback–Lyderson method.