Effects of chain conformation on miscibility, morphology, and mechanical properties of solution blended substituted polyphenylene and polyphenylsulfone

The effects of polymer conformation and degree of substitution on miscibility, morphology and mechanical properties of solution blended systems containing polyphenylsulfone and copolymers of phenylketone substituted p-phenylene with m-phenylene were studied. Static and dynamic light scattering studies were performed to obtain the z-average root mean square radius of gyration, second virial coefficient, weight average molecular weight and hydrodynamic radius. Solution blends of polyphenylsulfone with phenylene copolymers yielded free standing films. Blend miscibility was assessed by glass transition behavior, morphology was analyzed using atomic force microscopy and mechanical properties were measured using nanoindentation. Copolymer composition determined miscibility. Miscible blends exhibited homogeneous morphologies while immiscible blends displayed unique, heterogeneous morphologies. Polymer conformation in solution, rather than enthalpic contributions, was the primary determinant of miscibility. Successful reinforcement was achieved in blended systems.