Pre-treatment Of Carbon Nanotubes/Nitrogen Compounds By Ball-milling And Its Influence On Epoxy Composites

Due to good mechanical properties and physical properties, epoxy applications in aerospace, construction, electronic appliances and other fields, However, the disadvantages of the epoxy, such as poor toughness,low thermal conductivity and so on, directly affect its application; CNTs have become the ideal Nano-level reinforcement due to their excellent structural properties, But the dispersion of CNTs and their bonding performance with the substrate interface have been the bottleneck of their performance.In this paper, TETA, PEA and DETDA were grafted onto the surface of CNTs by mechanical ball milling, and the dispersibility of carbon nanotubes was compared by means of characterization. The results show that the dispersion of CNTs after modification is improved obviously,And the modified CNTs are more dispersible in the curing agent having the same group as the grafting compound, According to the curing agent and matrix type used in the preparation of the composite material, We choose the appropriate compound to graft modified CNTs. In this paper,the effects of milling conditions on the morphology and grafting rate of CNTs were investigated and the best milling technology was found. The tensile strength, flexural strength and heat resistance of the modified CNTs were significantly higher than those of unmodified CNTs, and the PEA grafted CNTs in all aspects of performance are better than the other two substances grafted CNTs. The curing kinetics studies show that the activation energy of the resin can be increased with the addition of the modified CNTs. The conductivity of CNTs was increased by 219% and 194%, respectively, with urea and ammonium bicarbonate. The nitrogen doped CNTs are superior to other CNTs in the enhancement of thermal conductivity and electrical conductivity of epoxy resin composites. The effect of CNTs on the thermal conductivity of resin matrix was also investigated, Based on the analysis of thermal, electrical and mechanical properties of epoxy, Indicating that the ball milling has little damage to the structure of CNTs. The thermal conductivity of MWCNTs-PEA/EP system is better than that of MWCNTs-NH2 / EP system under the same amount of addition.