Molecular dynamics simulation of grafting and modification of insulation paper cellulose

Abstract

In the daily operation of oil-immersed power transformer, with the increase of temperature, thermal aging happens to the insulation paper, resulting in the decrease of mechanical properties of insulation paper and the decrease of thermal stability. In order to improve the thermal stability of transformer insulation paper, the insulating paper cellulose was grafted and modified by polysiloxane. Then, the differences of elastic modulus, the mean square displacement and the end-to-end distance of cellulose chain before and after the modification were researched through molecular dynamics simulation. Results showed that the elastic modulus of insulation paper cellulose in the modified model was larger than that of unmodified model, and the mechanical properties of modified model were also improved. While, the mean square displacement and the end-to-end distance of cellulose chain of modified model were smaller than those of unmodified model, which means the mechanical properties of modified cellulose were improved. Therefore, it is concluded that using polysiloxane to graft and modify cellulose can improve the thermal stability of cellulose insulation paper.