Generation of internal stress in the process of solidification of synthetic resin, II : internal stress caused by shearing force

Abstract

Experiments were planned to ascertain the residual stress occurring in amorphous solid of high polymer. For this, injection molded articles of α-methylstyrene--styrene copolymer and bis-phenol-polycarbonate were used, and dilatometric measurement on the pellet form of the polymers and measurements on heating deformation were adopted. As the results, it is clarified that deformation by residual stress begins to occur at the lower limiting temperature of 2nd order transition region, and considering the activation energy of deformation calculated from rate constants of experimental deformation, the residual stress may be due to the orientational configuration of polymer molecules by molten flaw at the injection procedure.