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水溶性聚合物水溶液中存在聚合物和水之间的氢键缔合化学平衡 ,溶液的混合Gibbs自由能由氢键缔合化学平衡和Flory Huggins理论二部分组成 ,在此基础上建立了能描述水溶性聚合物液 -液平衡的氢键缔合模型。将该模型用于研究PEG2 180 -水和PEG2 2 90 -水两个体系的液 -液相平衡 ,计算值能较好地吻合实验值。由该模型得到的氢键生成焓的数值和符号能够用于解释在水溶性聚合物水溶液中 ,存在低临介溶液温度 (LCST)的现象。应用氢键缔合模型计算了水溶液中水的化学位。在不同温度下水的化学位随聚合物体积分率的变化规律 ,能够阐明同时存在高临介溶液温度 (UCST)和低临介溶液温度 (LCST)的水溶性聚合物液 -液相平衡的特征
The water-soluble polymer aqueous solution has the chemical bond of hydrogen bond between the polymer and the water. The mixed Gibbs free energy of the solution is composed of two parts by the hydrogen bonding chemical equilibrium and Flory Huggins theory. Based on this, Hydrolytic Polymer Liquid - Liquid Equilibrium Hydrogen Bond Association Model. The model was used to study the liquid - liquid equilibrium of two systems, PEG2 180 - water and PEG2 2 90 - water, and the calculated values were in good agreement with the experimental data. The values and symbols of hydrogen bond formation enthalpies obtained from this model can be used to explain the presence of a low LCST in water-soluble polymer aqueous solutions. The chemical bond of water in aqueous solution was calculated by using hydrogen bond association model. The change of the chemical position of water with the volume fraction of polymer at different temperatures can clarify the characteristics of the liquid-liquid equilibrium of water-soluble polymers in the presence of high UCST and low LCST