Melt rheology of the polyether from bisphenol-a and 4,4'-dichlorodiphenylsulfone

The melt rheology of polysulfone was studied in steady shear and oscillatory shear flow. Even when melt viscosity data were corrected for the dependence of the glass transition temperature on M n the viscosity molecular weight relation was not a simple power law over any appreciable range. The melt compliance is very low and reaches its maximum value at molecular weights > 2000. Since the molecular flexibility, measured as the size of the equivalent random segment of rubber elasticity theory, is similar to that of other common polymers, this suggests that the polar nature of polysulfone is contributing to the high “entanglement” density.