2009 Volume 3 Issue 11 Pages 1193-1201
Thermoplastic resin is often used to form molded material without post-curing or aging treatments. Creep and physical aging occur simultaneously in such material, and these effects are dependent on the time and temperature. The effects of physical aging after molding are also dependent on the thermal history of the material, and this has a large influence on the mechanical properties, especially creep. It is therefore necessary to control the progress of physical aging when designing materials. In this study, we examined the creep deformation of polycarbonate to determine the thermal history as the effect of physical aging on the creep behavior. The physical aging effects had a distinct time and temperature dependency that also affected the density of the material. Our findings showed that it was possible to calculate the effect of the thermal history on physical aging using only the relationship between physical aging and density.