ABSTRACT
Radiation processing of polymers was introduced after World War II with the development of the nuclear reactor. In the current years, various radiation sources, e.g., X-rays, gamma and ultraviolet rays and electron beam are being widely used. Evidence indicates that in most cases, for organic materials, the predominant intermediate in radiation chemistry is the free radical. It is only the highly localized concentrations of radicals formed by radiation, compared to those formed by other means, that can make recombination more favored compared with other possible radical reactions involving other species present in the polymer. From a practical stand point almost any of the lower-molecular weight vinyl monomers, cross-linking oligomers, and polymers can be blended with a high-molecular weight thermoplastic polymer to enhance cross-link density at lower dose rates. Aromatic molecules like benzene, styrene, naphthalene, anthracene, and aromatic plasticizers serve to act as local traps for excitation energy after it is deposited in the material.
