Chain scission and mechanical failure of polyethylene

The role of chain scission in the mechanical degradation of polyethylene has been examined using Fourier transform infrared spectroscopy to measure changes in molecular end group concentrations. The increase in chain scission concentration during cyclic fatigue of ultrahigh molecular weight polyethylenes has been investigated by this technique. The concentration of chain scissions at macroscopic failure was independent of the peak stress and time to failure in the fatigue experiment, but dependent on fatigue test frequency and molecular weight.