Ultraviolet Spectroscopy of Irradiated Polyethylene

Abstract
When polyethylene has been irradiated with high‐energy radiations ultraviolet absorption bands having peaks at 229, 236, 245, 258, 264, 275, 285, 288, 307, 323, 340, 359, and 396 mμ can be observed. The bands are most clearly distinct at liquid‐nitrogen temperature, but some can only be observed after the decay of free radicals on admission of oxygen at room temperature. The assignment of these bands to conjugated polyene and polyenyl free‐radical groups is given and discussed.