| 초록 |
In this work, high pressure cloud-point behavior were reported for poly(vinyl stearate) [P(VS)] in carbon dioxide, propane, propylene, butane, 1-butene, and dimethyl ether (DME), as well as for the P(VS) + vinyl stearate (VS) ( or DME, acetone, ethanol) in supercritical CO2. Phase behavior for P(VS) in C3 hydrocarbons were about 20 MPa higher than P(VS) + C4 hydrocarbons curves, at a fixed temperature of about 393 K. The cloud-point curve for the P(VS) + DME mixture was located between C3 and C4 hydrocarbons at pressures below about 20.0 MPa. The P(VS) + CO2 + 63.0 wt% VS phase behavior curves intersect a fluid → liquid + vapor (LV) curve at temperatures of 353.6 K (at 24.5 MPa). The location of the P(VS) + CO2 cloud-point curve shifts to lower temperatures and pressures upon the addition of acetone or ethanol. High pressures phase equilibrium data were presented for the CO2 + VS system at temperatures ranging from (313.2 to 393.2) K and pressures up to 27.4 MPa. The CO2 + VS system exhibits type-I phase behavior with a continuous critical mixture curve and was modeled using the Peng-Robinson equation of state. |
