High-strength carbon nanotube/epoxy resin composite film from a controllable cross-linking reaction

Carbon nanotubes (CNTs) have been considered as potential reinforcements for various composites due to their excellent mechanical properties. However, it is still a challenge to prepare high-performance CNT/resin composites, resulting from the weak interfacial bonding between individual CNTs or that between CNTs and resin. Herein, a facile and effective method for preparing high-strength CNT/epoxy resin (EP) composite films is put forward, consisting of a controllable cross-linking treatment to the well-aligned CNT films and subsequent chemical filling with EP. Benefiting from the synergistic effects of optimized cross-linked CNTs and further enhancement by EP, the tensile strength of the obtained CNT/EP composite film reaches 2.5 GPa, which is about 5 times that of the raw CNT film. Our study might provide an effective strategy toward the preparation of highperformance CNT composite materials.