Enhanced Insulating Paper of Aramid/Polyphenylene Sulfide Composites With Fibrillated Fibers

ABSTRACT Aramid paper is extensively utilized in aerospace and insulation applications due to its superior mechanical properties and insulation performance. Nevertheless, the smooth surface and high chemical inertness of aramid fibers significantly limit their potential applications in these domains. In this study, aramid fibrillated fibers initially were prepared through the valley beating mechanism. Subsequently, aramid short fibers, fibrillated fibers, and polyphenylene sulfide (PPS) pulp were integrated through wet papermaking and hot pressing to produce aramid/PPS composite paper (F‐ACFs/PPS paper). The aramid fibrillated fibers exhibited a larger specific surface area which facilitated a synergistic bonding effect. During the molten infiltration of PPS pulp with the fibers, there was a significant reduction in pores and defects within the composite paper. Consequently, the tensile strength and electric breakdown strength of the F‐ACFs/PPS composite paper reached 119.6 N/cm and 49 kV/mm respectively, with 1.4 times enhanced insulation performance compared to ACFs/PPS paper. Furthermore, the F‐ACFs/PPS paper maintains structural stability at 300°C, demonstrating excellent thermal stability. Thanks to the integration of enhanced thermal performance, mechanical strength, and insulation properties in F‐ACFs/PPS, F‐ACFs/PPS showed a promising candidate for applications in the aerospace industry and the field of insulation.