In this research a novel model was proposed for calculation of the phase behavior in polymer solutions. The proposed model consists of modified Freed-FV, non-randomness factor and the new expression derived volume-based group contribution local composition model activity coefficients. Firstly the proposed model was considered without pseudo chemical part to obtain the interaction parameters of functional groups (This is for the use of interaction parameters of functional groups in various systems). The binary interaction parameters of the functional groups of new local composition model have been calculated by correlation of the experimental vapor-liquid equilibria (VLE) data with different molecular weights (M_W) and temperatures of several polymers. The interaction parameters of functional groups were reported and the deviations of new local composition model were compared with UNIFAC and Entropic-FV models and proved the proposed model has an acceptable advantage over the mentioned models. By obtaining the practical interaction parameters of functional groups, the proposed model was applied for modeling of liquid-liquid equilibria (LLE) of polymer-polymer aqueous two-phase systems. Also, it was compared with UNIQUAC and UNIQUAC-NRF models. The suggested model consists of three adjustable parameters. Moreover, the coordination number was developed based on molar fraction and molecular size of solution components. The results revealed that the proposed model can predict aqueous multicomponent polymer systems with great precision.

在这项研究中，提出了一种用于计算聚合物溶液中相行为的新型模型。所提出的模型由修正的Freed-FV，非随机因子和新的表达式导出的基于体积的基团贡献局部组成模型活动系数组成。首先，将所提出的模型考虑为没有伪化学部分，以获取官能团的相互作用参数（这是为了在各种系统中使用官能团的相互作用参数）。通过将实验汽液平衡（VLE）数据与不同分子量（M _W）和几种聚合物的温度。报告了官能团的相互作用参数，并将新的局部组成模型的偏差与UNIFAC和Entropic-FV模型进行了比较，证明了所提出的模型比上述模型具有可接受的优势。通过获得官能团的实际相互作用参数，将所提出的模型用于聚合物-聚合物水两相体系的液-液平衡（LLE）建模。此外，将其与UNIQUAC和UNIQUAC-NRF模型进行了比较。建议的模型包含三个可调参数。此外，配位数是根据溶液成分的摩尔分数和分子大小而开发的。结果表明，所提出的模型可以非常精确地预测水性多组分聚合物体系。