基于分子动力学方法的复合绝缘子硅橡胶热老化机理研究OA

Currently,research on the thermal aging of composite insulators mainly relies on experimental methods,yet there is a lack of understanding of microscopic dynamic changes in the process of thermal aging.Based on the method of reaction field molecular dynamics,the author examines the pyrolysis process of composite insulators at the microscopic atomic level.It is found that the thermal aging of com-posite insulators is primarily caused by the fracture of Si-CH3,C-H,Si-O in silicone rubber mate-rials,and the formed products mainly include CH4,C2 H4,H2,and some small molecular siloxanes.With continuous pyrolysis,the number of newly generated Si-Si and Si-H bonds in the molecular structure of silicone rubber increases continuously.Si-Si bonds increase the crosslinking degree of sili-cone rubber materials,while Si-H bonds are easily hydrolyzed to form-OH.The aged silicone rubber's dielectric constant is calculated,revealing that the relative dielectric constant of the aged silicone rub-ber material increases,leading to a further increase in dielectric loss.