Effect of pre-heat treatment on the static and dynamic thermo-mechanical properties of ultra-high molecular weight polyethylene

In the present work, a dynamic thermo-mechanical analysis technique has been used to investigate the effect of pre-heat treatments on the visco-elastic properties of Ultra-High Molecular Weight Polyethylene (UHMWPE) as a function of frequency and temperature. These properties include storage modulus (E′) and loss modulus (E″). The UHMWPE specimens were pre-heated at 50, 80 and 100 °C for periods of 2 and 4 h, respectively. The effect of these pre-heat treatments on the quasi-static mechanical properties (Young's modulus, yield strength, fracture strength, ductility and micro-hardness) has also been investigated. Finally, the degree of crystallinity of the UHMWPE has been measured as a function of pre-heat treatment time and temperature. The results show a strong dependence of most of these properties on the degree of crystallinity which is a function of pre-heat treatment temperature and duration.