Abstract
Freeze‐dried single crystals of unfractionated Marlex 6009 polyethylene were irradiated at various doses up to 100 Mrad. Analysis of the data of the present work and those of others showed that the decay of vinyl groups can be best described by second‐order kinetics. The decay rate constant is found to increase with decrease in original concentration of vinyl groups. It has been concluded that the increase in the decay rate constant with decrease in initial vinyl concentration is due to a decrease in crystallinity. Some supporting evidence has been presented for this conclusion.