Molecular dynamics simulation of the effect offree radicals on epoxy resins under high altitude and strong radiation environment

A variety of free radicals induced by strong ultraviolet radiation at high altitudes can cause the epoxy resin, the insulating material for bridge arm reactors, to crack, leading to the degradation of its performance, and it is crucial to clarify the cracking products and the effects of different free radicafs on the epoxy resin. In this paper, the molecular dynamics simulation method is used to study the cracking products of epoxy resin under two kinds of free radicals, CH3 and CHOH, and to compare the degree of damage of the two kinds of free radicals on epoxy resin. It is shown that CH3 and CHOH radicals react with epoxy resins, resulting in C-H bond cleavage and the formation of small molecule products such as H2 and H2O. The higher activity of the CHOH radicals, which contain more electronegative oxygen atoms, resulted in more severe degradation of the epoxy resin, with the production of more H2, H2O and CO. The simulation data showed that the degradation of the epoxy resin under the action of the CHOH radicals was more than twice as high as that under the action of the CH3 radical, and that there was a significant increase in the number of small molecule products. This study compares the degree of degradation of epoxy resin by different radicals at the microsco pic level, clarifies the main types of decomposition products, and provides a theoretical basis for the modification of epoxy resin to resist radiolysis materials, which is essential to ensure the stable operation of electrical equipment in high altitude environments.