On line construction of carbon nanotube/polytriazole composite films with high tensile and heat resistant properties

Carbon nanotubes (CNTs) have low densities and excellent mechanical properties due to their unique one-dimensional tubular structures, and are thus considered as an ideal reinforcement for lightweight and high-strength resin-based composites. However, it is still difficult to prepare high-performance composites with a high content of well-aligned CNTs. Besides, limited by the poor heat resistance of epoxy resin, it is still challenging to prepare composites with both high strength and heat resistance. In the present study, a simple on-line process is proposed to prepare CNT/polytriazole composite films. That is, a CNT assembly just having formed in a high temperature reactor is pulled through solution containers for shrinking and resin infiltration and subsequently winded on a drum to form a composite film. By optimizing the resin content and CNT alignment for better densification and inter-binding, the tensile strength of the composite film can reach a high level of 2.52 GPa with a decent elongation of 4.3 %. Associated with the use of the polytriazole resin, the composite could be cured at a low temperature of 80 °C but have a high glass transition temperature of 298 °C. Thus, the present technique is useful for preparing high-strength composite materials which are required to be able to be cured at low temperature but applied at high temperature. A simple on-line process is proposed for preparing high-strength and heat-resistant composites. [Display omitted] •An on-line approach is proposed for making composites with a controllable resin content and carbon nanotube alignment.•The preparation is carried out continuously in an open air environment.•The composites possess a high tensile strength (2.52 GPa) and heat resistance (glass transition temperature = 298 °C).•The composites are cured at a low temperature of 80 °C.