Long-term strength of polymethylmethacrylate under the influence of liquid media and elevated temperatures

The combined effect of liquid media and elevated temperatures on the long-term strength of polymethyimethacrylate (PMM) was studied. It was shown that the nature of the time- and temperature-dependence of strength is changed when PMM is under the influence of liquid media. An empirical expression for the time-to-rupture was derived.