Preparation of high breakdown strength meta-aramid composite paper reinforced by polyphenylene sulfide superfine fiber

Meta-aramid paper has been widely used in transformers because of its excellent insulation properties and thermal stability. However, with the rapid development of high-voltage transformers, higher requirements are placed on the breakdown strength of meta-aramid paper. In this study, meta-aramid chopped fibers/polyphenylene sulfide (MACFs/PPS) composite paper was prepared by a combination of wet-copying and hot-rolling technology. Then the microscopic morphology, mechanical properties, crystallization behavior, insulation properties, and thermal stability of the MACFs/PPS composite paper were studied and evaluated. The experimental results showed that the breakdown strength of the MACFs/PPS composite paper was as high as 46.46 kV/mm, which was 2.7 times higher than the famous Nomex T410 insulating paper. Meanwhile, the MACFs/PPS composite paper presented good mechanical properties and thermal stability. This paper provides a simple and versatile method for the preparation of meta-aramid composite paper with high breakdown strength.