Miscible polymer blends are of interest as materials in their own right and for implementing strategies for compatibilizing multiphase mixtures. This research deals with the opportunities for designing miscible polymer pairs when one or both components are copolymers. A modern equation-of-state approach is likely to provide a rational theory that can make predictions from minimal information. This research integrates polymer synthesis, characterization (molecular, thermal, volumetric, etc), and careful phase-diagram determination into a scheme that allows calculation of interaction energies (stripped of the complicating effects of compressibility) for various pairs of monomer repeat units, even when they energetically resist mixing. The focus is on a variety of polycarbonates, copolymers formed from styrene, methyl methacrylate, acrylonitrile, and polymers containing functionally reactive monomers. The goals are to perfect this scheme, to produce a reliable matrix of binary interaction energies that will allow accurate design of miscible blends from multicomponent polymers, and to identify blend concepts that will be useful especially in the area of reactive compatibilization. This research will help the growing field of polymer mixtures, which are increasingly being used as engineering plastics and are also commonly found in recycled plastics. A better understanding of the fundamentals underlying these uses is essential to further progress.
