气液色谱法研究聚合物/溶剂体系气液平衡

The Study of Vapor-Liquid Equilibria for Polymer/Solvents by Using Gas-Liquid Chromatography

用气液色谱法测定了聚二甲基硅氧烷（PDMS）／溶剂、聚甲基丙烯酸甲酯（PMMA）／溶剂体系在不同温度下以质量分数表示的无限稀溶剂活度系数和Flory－Huggins相互作用参数。应用UNIFAC和UNIFAC－FV模型对PDMS／溶剂、PMMA／溶剂体系中以质量分数表示的无限稀溶剂活度系数进行了估算。结果表明，用这两个模型预测PDMS／溶剂、PMMA／溶剂体系中的无限稀溶剂活度系数有待修正或采用其它模型进行估算。

The infinite dilution weight fraction activity coefficient, Ω~∞_1, and Flory-Huggins interaction parameter, X, have been determined for systems of polydimethylsiloxane (PDMS)/solvents and polymethylmethacrylate (PMMA)/solvents by using gas chromatography from 58℃to 180 ℃. 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 thatΩ~∞_1 and X were decreased with the increase of temperature in the range from 58℃ to 180℃. The study showed that UNIFAC and UNIFAC-FV models could not all be used to estimate Ω~∞_1 of the solvents in PMMA/solvent systems. Therefore, UNIFAC and UNIFAC-FV models must be corrected or other models must be used.