Aminated aligned carbon nanotube bundles/polybenzimidazole hybrid film interleaved thermosetting composites with interface strengthening action

It is always a big challenge to effectively enhance the impact resistance without sacrificing the processability and thermal stability of thermosetting composites. High performance diallyl bisphenol A modified bimaleimide (BD) thermosetting composites are fabricated by interleaving aminated aligned carbon nanotubes bundle (ACNTB-NH2)/polybenzimidazole (PBI) hybrid films. Because the hybrid film contains −NH2 and −NH− and ACNTB-NH2 protrudes from the film surface, the chemical interfacial interaction can be formed at hybrid film/matrix resulting from the reaction of −NH2 and −NH− in hybrid film and C=C in BD system, and the interface is strengthened by ACNTB-NH2 that can join the polymers together at the bimaterial interface like a rivet. The resultant BD/[5%ACNTB-NH2@PBI]n composites show greatly improved thermal stability and mechanical properties without sacrificing good dielectric property of BD, which can be attributed to the high inherent integrated properties of PBI hybrid films and the interface strengthening action between PBI hybrid film and BD matrix. The carbon fiber reinforced BD composites with PBI hybrid film interleaves are also fabricated, the mechanical properties of resultant composites show increasing trends with the increase of PBI hybrid film layer. Eventually, the flexural strength, impact strength and interlaminar shear strength of CF/BD/[5%ACNTB-NH2@PBI]5 increase by 16%, 42% and 33%, respectively, compared to those of CF/BD composite.