Ternary Solid–Liquid Equilibria of Semicrystalline, Branched Polymer Solvent Mixtures—A Theoretical Study by Means of Lattice Cluster Theory

Analytical polymer separation techniques, like CRYSTAF (crystallization analysis fractionation) and TREF (temperature rising elution fractionation), play a crucial role in gaining insight into the interrelation between molecular architecture and properties. Often polymer samples are semicrystalline, as it consists of amorphous regions which exhibit a liquid-like structure, and ordered crystallized structures called crystallites. Additionally, polymers exhibit a certain degree of short-chain branching, and they are polydisperse with respect to molecular weight and chemical composition. To explain the theoretical background of common polymer separation techniques, a fair prediction of solid–liquid equilibria (SLE) of polymer solvent systems is required. By application of Lattice Cluster Theory (LCT), developed by Freed and co-workers, the molecular architecture can be considered. Recently, LCT was applied to calculate the SLE of binary semicrystalline, high-polymer solvent mixtures having an arbitrary molec...