Dynamic mechanical behaviour and phase separation of mixtures of polysulfone with bis[4‐(4‐ethynylphenoxy)phenyl]‐sulfone or poly(phenylene sulfide)

Abstract The dynamic mechanical behaviour and microphase‐separation structure of polysulfone blends with bis[4‐(4‐ethynylphenoxy)phenyl]sulfone and with poly(phenylene sulfide) were investigated using torsional braid analysis and scanning electron microscopy. The experimental results showed that the size and shape of dynamic mechanical damping peaks and the structure characteristics of polysulfone blends with sulfur‐containing polymers do not only depend on the chemical and physical nature and the weight fractions of the two components but also on conditions of thermal treatment leading to cross‐linking reactions. In these multi‐component polymer systems, the initially compatible mixture turns into an incompatible two‐phase system during heating.