Simha_et_al-1984-Polymer_Engineering__Science英文文献资料.pdf

Statistical Thermodynamics of Blends: Equation of State and Phase Relations ROBERT SIMHA and R. K. JAIN Department of Macromolecular Science Case WesternReserve University Cleueland, Ohio 44106 We discuss the free-energy expressions for homogeneous melts and their blends, based on our hole theory. Equation of state (PVT) and free energy of mixing (AC,) are considered from a common point of view without the introduction of additional parameters to pass from the first to the second set of properties. Practical problems arise from the fact that AG, represents a difference between large quantities. As illustra- tions we analyze two typical systems. One is the n - c6 + n - c16pair where PVT and AGm,the latter at atmospheric pressure only, have been studied experimentally. The other is n - Cg with a low and high molecular weight respectively of polyeth- ylene as solute. Here the PVT relations of the components only are known. The effects of intercomponent attractions, temper- ature, pressure, and molecular weight on phase behavior are investigated. Critical coordinates, lower critical-solution tem- peratures (LCST) and their pressure depen