The Mechanism of Radiation Destruction of Dyes in Polymers: A New Method for Increasing the Stability of Dyed Polymers Based on Oscillative Cross-Relaxation

Discussion of the mechanism of radiation destruction of dyes in polymers, which is associated with solid-phase chemical reaction between dye molecules and oxyradicals appearing either on destruction of polymer molecules or on oxidation of macroradicals by the oxygen dissolved in the matrix. Experimental results are given on radiolysis and photolysis of polymethyl methacrylate with a "resonant" low molecular weight additive and dye (nickel dithiobenzil complex and vanadyl phthalocyanine), which demonstrate the decisive role of oscillative cross-relaxation between macromolecules and molecules of the additive in increasing the radiation stability of dyed polymers.