Fundamental aspects of the radiolysis of solid polymers, crosslinking and degradation

Possibly, the two most important processes in the radiolysis of polymers are crosslinking and degradation. This is true in both a fundamental and applied sense. In order to discuss these radiation induced processes, many of the fundamental, i.e. initial short lived events are considered. The techniques used are primarily rapid subnanosecond pulsed radiolysis with pulses of 0.4 mev electrons, and irradiation at low temperatures, coupled with spectroscopic techniques. In some instances it is instructive to compare and contrast the radiolytic data with similar studies using pulsed laser methods, where the energies are much less, while the resulting radiation induced processes are simpler.From a chemical view point, much can be gained from considering similar radiolytic process in simple liquids. In order to cover a reasonable gambit, the following three polymers, polyethylene, polyvinyl alcohol, and polystyrene, receive particular attention, and are compared to the radiolysis of hydrocarbons, alcohols, and alkyl benzene. Data on copolymers of the above are also reported, and compared to the radiolysis of comparable liquid mixtures.In a nutshell, the paper incorporates recent fast pulsed radiolytic, spectroscopic and laser studies to describe early radiation induced events in polymer systems. The discussion of mechanism also brings in data from other laboratories in this area of research.