Surface Modification Of Carbon Nanotubes And Research Of Epoxy Resin Composites

With their chemical inactivity, extremely mechanical strength and well electronic properties, carbon nanotubes （CNTs） are a one-dimension nanostructural materials. The huge molecular weight of CNTs leads to their indissoluble, which limits the research of their chemical character. However, after CNTs’ structures are modified and produce some active functional groups on them, such as - OH, -COOH and so on, the organic chemical reactions between CNTs and some organic compound are feasible.In this work, we modified CNTs with amine group by reacting with 1,6-hexamethylene diamine （HMD）. Before this modification, the efficient methods for purification and shortening of multi-walled carbon nanotubes （MWNTs） have been investigated. TEM, Elementary analysis and FT-IR spectra indicated that the MWNTs were oxidized into carboxylic group(v_C=O=1705 cm^-1). Then the carboxyl-terminated MWNTs reacted with 1,6-hexamethylene diamine （HMD） with the aid of the condensation agent N,N-dicyclohexyl carbodiimide （DCC）. The modified MWNTs were characterized with Elementary analysis, XPS, and FT-IR spectra. After the condensation reaction, 1,6-hexamethylene diamine （HMD） has been covalently anchored to the MWNTs through the amide-acyl bonding.In the second part of the work, the epoxy resin （EP） composite with raw and modified MWNTs were fabricated with varying loading of MWNTs using the method of melting blending. The SEM photographs of fracture surface of the composites show that the modified MWNTs was uniformly dispersed in EP matrix and compatible with the matrix. Loading of MWNTs can enhance the tensile and impact strength of EP, the tensile and impact strength increment of EP/modified MWNTs composite was higher than the value of EP/raw MWNTs composite, when the loading of modified MWNTs was 2wt%, the tensile and impact strength reached maximum.