The study of vapor-liquid equilibria for polymer/solvents by using gas-liquid chromatography]
气液色谱法研究聚合物/溶剂体系气液平衡

The infinite dilution weight fraction activity coefficient, omega 1 infinity, and Flory-Huggins interaction parameter, chi, have been determined for systems of polydimethylsiloxane (PDMS)/solvents and polymethyl-methacrylate (PMMA)/solvents by using gas chromatography from 58 degrees C to 180 degrees C. The solvents include styrene, acetone, ethyl ether, methanol, ethanol, acetic acid, trichloromethane, tetrahydrofuran and ethyl acetate in PDMS/solvent systems and n-hexane, n-heptane, cyclohexane, benzene, toluene, ethyl benzene, styrene, acetone, ethyl ether, methanol, ethanol, methyl methacrylate(MMA), trichloromethane, tetrahydrofuran and ethyl acetate in the PMMA/solvent systems. The results showed that omega 1 infinity and chi were decreased with the increase of temperature in the range from 58 degrees C to 180 degrees C. The study showed that UNIFAC and UNIFAC-FV models could not all be used to estimate omega 1 infinity of the solvents in PMMA/solvent systems. Therefore, UNIFAC and UNIFAC-FV models must be corrected or other models must be used.