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. [ABSTRACT FROM AUTHOR]