Abstract: To study the mechanical properties of outside mold decoration films, the true stressstrain curves under the corresponding conditions were obtained by uniaxial tensile tests of PMMA plastic sheets at high temperature with different temperature and strian rates, the coefficients of the viscoelastic constitutive model of DSGZ of different temperature and strian rate were calculated, and the predicted curve of DSGZ model and experimental data were compared and analysed. The analysis results show that at the same temperature the true stress, tensile ratio and yield strength would increase when the strain rate rose; at the same strain rate, the strain softening and yield phenomenon would decrease and then disappear, the true stress would also decrease when the temperature rose. The predicted curve of DSGZ model and experimental data were basically anastomotic, the mechanical properties of PMMA could be better reflected by the DSGZ model.

Key words: polymethyl methacrylate, outside mold decoration, constitutive model, mechanical property