Aging Comparison of the RTV and nano RTV insulator coatings due to thermal and electrical stress

RTV silicone rubber offers excellent high and low temperature resistance as well as UV and weathering resistance and has a bright future in the aerospace and electronics industries. On the other hand, the thermal decomposition behavior of polymeric materials significantly affects their aging process and there are many studies on improving the specifications of nanocomposites by adding different types of nanoparticles. In this work, silicone rubber RTV nanocomposites with low content of modified nano-ZnO particles and pure RTV were compared in terms of their degradation behavior by heat and electrical stress. The coatings were prepared and the products were subjected to various experimental tests, including thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR) analysis. The TGA results of the study suggest that the residual weight of the aged samples is higher than that of the unaged samples. The FTIR analysis results show that the aging performance of Nano-RTV is better than that of RTV, which is concluded from the smaller absorption area of the functional groups of Si-CH۳ and Si-O-Si. The numeric value of Critical flashover voltage in Nano-RTV coating was higher compared to the RTV coating as a result of the enhanced electrical insulation characteristics. This can confirm the improvement of thermal aging of Nano RTV compared to pure RTV and may prove useful to estimate the expected lifetime of the coatings, which is valuable for estimating the reliability of porcelain insulators

Keywords:

Aging characterization , Thermal stability , High voltage Room temperature vulcanized (RTV) coatings , Nanoparticles , Critical flashover voltage