Cosolvent Effect and Solubility Measurement for Butyl (Meth)acrylate Polymers in Benign Environmental Supercritical Solvents

Abstract

Cloud-point phase behavior curves to 190 °C and 2570 bar are measured for binary and ternary mixtures of poly(isobutyl acrylate)−CO2−isobutyl acrylate, poly(tert-butyl acrylate)−CO2−tert-butyl acrylate, poly(isobutyl methacrylate)−CO2−isobutyl methacrylate, and poly(tert-butyl methacrylate)−CO2−tert-butyl methacrylate systems. The phase behavior for the poly(isobutyl acrylate)−CO2−isobutyl acrylate system with cosolvent concentrations of 0, 3.2, 8.8, 18.1, 31.9, and 40.7 wt % are measured in the changes of the pressure−temperature slope. With 58.7 wt % isobutyl acrylate to the poly(isobutyl acrylate)−CO2 solution significantly changing, the phase behavior curves takes on the appearance of a typical LCST boundary. The cloud-point curves for the poly(tert-butyl acrylate)−CO2−0, 8.5, 14.9, 34.7, 56.0, and 57.7 wt % tert-butyl acrylate system changes the P−T curve from the UCST region to the LCST region as the tert-butyl acrylate concentration increases. The cloud-point curves for the poly(isobutyl methacryla...