Processing and composition dependence of the structure and mechanical properties of polycarbonate/Ultrax blends

Polycarbonate (PC)/Ultrax blends were obtained by injection molding changin g both the Ultrax content and the injection temperature, speed and pressure . The charge of injection speed or pressure did not lead to significant cha nge of morphology or properties. An injection temperature of 300 degrees C allowed some reaction to take place between the components and the presence of some reacted Ultrax in the PC-rich phase, but the mainly spherical morp hology obtained lead to poor mechanical properties. At a lower injection te mperature of 280 degrees C, however, reactions were almost not detected, bu t fibrillar structures were produced, mainly because of the higher matrix v iscosity. This gave rise to important increases not only in modulus and ten sile strength but also in flexure properties and creep dimensional stabilit y.