Amorphous polymers which have been deformed plastically at room temperature almost recover their original shapes at temperatures above their glass-transition temperature. The shape recovering behavior during raising temperature is significantly affected by the temperature distribution in the polymer specimens, which have essentially low thermal conductivity.
In this paper, the influences of the lateral size of specimens and the surface temperature on the recovering behavior of poly (vinyl chloride) heated in an air oven were investigated experimentally and the results were compared with the numerical calculations obtained by using the equation of heat conduction.
The results show that when the specimen is considered as a bundle of many fibers, the calculated shape recovery of tensile or torsional deformation agrees with the experimental results and the behavior of model described above also agrees with the experimental result of the specimen having localized neck.
