Out-of-phase thermo-mechanical coupling behavior of proton exchange membranes

▶ The mechanical properties of PEM under thermo-mechanical coupling loading were studied in this study. Very few data were reported on the issue. ▶ Under the proportional loading, the deformations of the membrane were resulted from thermal expansion, the cyclic ratcheting strains and creep strain caused by non-zero ambient stress. ▶ In the cases of rectangular path loading, the elastic behavior of the membrane at the low temperatures can be explained by the freezing of water content in the material and the transition of the non-ionic matrix. ▶ In the case of thermal loading tests, the thermal stress is history-dependent with temperature, i.e. the thermal stress is different in the warming process and the cooling process at the same temperature.