2001 Volume 50 Issue 12Appendix Pages 243-248
The effect of the amount of applied deformation on a thermally stimulated deformation recovery for a largely deformed epoxy resin under its glass transition temperature was studied in this paper. Two recovery peaks have been observed in the thermally stimulated deformation recovery curves for both epoxy resin and poly (methyl meth acrylate) (PMMA). The lower temperature recovery peak of the PMMA shifts to a higher temperature with increasing applied strain. However, the lower temperature recovery peak of the epoxy resin was independent of the amount of applied strain. The effect of applied strain on the relaxation curves for the epoxy resin was more significant than for the PMMA. Free deformation recovery curves below the glass transition temperature were simulated using a generalized Maxwell model both with and without the dependence of the recovery curve on the amount of applied strain. The model with strain dependence included reproduced the tendency of the experimental results of the epoxy resin more closely than the model without strain dependence. It seems that the structure of the epoxy resin changed after the lower yielding range to a structure which restricts the relaxation of polymeric structures.
