Effect of flaws on the time-temperature superposition in the ultimate behavior of elastomers

Abstract

The effect of flaws on the ultimate behavior of poly (β-hydroxyethyl methacrylate) swollen with water to equilibrium has been examined experimentally, by using test pieces containing model defects. For both the defect-free samples and samples with macrodefects the experimental dependences of the time to break on stress have been obtained at various temperatures. The curves corresponding to different temperatures are approximately parallel to each other, the temperature dependence of shift factors obeys the Williams-Landel-Ferry equation. The presence of macrodefects in the test pieces accounts for the change in shape of the time-to-break curves and influences distinctly the value of the characteristic temperature Ts determined from the temperature dependence of the shift factors. This effect has been ascribed to the high orientation in the roots of the macroscopic defects.