Ultra-low hygroscopic polyimide/polyaniline composite nanofiber membranes for antistatic protection and thermal insulator

Polyimide (PI) materials with excellent mechanical properties, chemical resistance and thermal stability were attractive candidates for the defense, aerospace and microelectronics industries. However, the antistatic and hygroscopic properties of PI materials need to be further improved in these industries. In this work, 2,2′-bistrifluoromethoxy-biphenyl-4,4′-diamine (TFMOB) containing trifluoromethoxy (−OCF 3 ) groups as the diamine monomer of PI, 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) as the dianhydride monomer of PI and dodecyl benzene sulphonic acid doped polyaniline (DBSA-PANI) as the antistatic agent, and a series of polyimide/polyaniline composite nanofiber membranes (PI/PANI-CNFMs) were prepared via electrospinning. The hygroscopicity of PI/PANI-CNFMs was 0.96 − 1.36 %, lower than that of most reported PI nanofiber membranes. Among these nanofiber membranes, the volume resistivity of 90PI/10PANI-CNFM was 5.58 × 10 8 Ω·cm, which met the standard for antistatic materials (10 6  − 10 9 Ω·cm). Meanwhile, PI/PANI-CNFMs also showed low dielectric constant of 1.65 − 1.92, high limiting oxygen index (LOI) value of 30.8 − 40.1 % and low thermal conductivity of 0.143 − 0.086 W·m −1 ·K −1 , indicating that they had a promising potential for applications in the defense, aerospace, and microelectronics industries.