Radiation-Stimulated Oxidation of Naturally Aged Polyethylene Films

Resumo

The kinetics of formation of carbonyl groups in naturally aged polyethylene films under the action of ⁶⁰Co γ-radiation was studied, and the specific power consumption in the process was determined. The radiationstimulated oxidation of the aged films (in contrast to model freshly prepared samples) is a self-accelerating process occurring by at least two mechanisms. One of them is a chain process, and the other, most probably, involves the reaction of oxygen with the trans-vinylene unsaturated moieties initially localized in the crystalline phase of polyethylene. On the whole, the aged polymer materials exhibit increased tendency to oxidation under irradiation, which restricts the use of items based on them under the conditions of the action of high-energy radiation.