Flory状态方程理论与聚合物混合物的热力学

由Flory状态方程理论的化学位公式推导了二元混合物的亚稳单相极限线,同时导出了状态方程参数的温度、压力依赖性,计算表明Flory理论是可以像McMaster修正理论一样描述聚合物的相溶性行为的。 指出前人的工作由于假定相互作用能和熵参数均为0,分子量和状态方程参数对相界的影响被誇大了,相分离也只发生在很窄的浓度范围内。如果考虑了实际体系中相互作用能和熵参数均不为0,上述因素对相界的影响以及相界的形状将趋于合理。

THE FLORY EQUATION OF STATE THEORY AND MISCIBILITY OF POLYMER MIXTURES

Spinodal has been derived from the chemical potential of the Flory equation of state theory. Also given are the temperature and pressure dependences of the equation of state parameters. Calculations show that the Flory theory describes the compatibility behaviour of polymer mixtures as well as McMaster's modified treatment did.It is pointed out that previous work exaggerated the influence of molecular weight and the equation of state parameters upon phase diagram and predicted a narrow concentration region for phase separation on the assumption that X₁₂=O and Q₁₂=O,where X₁₂ and Q₁₂ are interaction energy and entropy parameters,respectively. For practical systems X₁₂=O and Q₁₂=O,the influence of these factors upon phase diagram and the shape of phase diagram will be predicated to be reasonable as compared with experi-ment.