In this study, high-speed tensile testing for notched specimen is conducted to investigate the impact property of Polydimethylsiloxane copolymerized Polycarbonate (PDMS-PC) compared with Polycarbonate (PC). Depending on the test temperature and tensile speed, brittle or ductile fractures are observed for PC. However, only ductile fractures are seen for PDMS-PC even at the high speed 7000mm/s and low temperature 243K. The impact properties are also considered in terms of the time-temperature superposition principle. Then, master curves for the final fracture elongation for both PC and PDMS-PC are constructed in terms of the strain rate at the notch in conjunction with shift factors. The fracture behavior can be predicted for the wide range of impact speed under various temperatures from these master curves.