Here we present time-temperature and time-aging time superposition data for a commercial grade polycarbonate. The data reduction is performed for dynamic-mechanical data obtained in torsion over a range of temperatures from 103.6 to 144.5°C and aging times of 16 h. For time-temperature superposition the results show the deviation of the sub-Tg response from the WLF equation. Two response regimes are observed: at temperatures far below Tg the log(aT) is linear in T, followed by a transition towards the WLF behavior as Tg is approached. The temperature at which the behavior changes from a linear dependence of log(aT) on T to the transition-type behavior is found to depend on the aging time. This temperature decreases as aging time increases. The time-aging time response is found to behave in a normal way. At temperature far below Tg the log (ae) vs log(te) is constant and has a slope somewhat less than unity. However, nearer to Tg the slope decreases and there is a second regime of in which the aging virtually ceases. In this polycarbonate, above 136.9°C, no aging is observed.
|Number of pages||7|
|Journal||American Society of Mechanical Engineers, Applied Mechanics Division, AMD|
|State||Published - 1995|
|Event||Proceedings of the 1995 Joint ASME Applied Mechanics and Materials Summer Meeting - Los Angeles, CA, USA|
Duration: Jun 28 1995 → Jun 30 1995