(95b) Covalent/Non-Covalent Dispersion of Eb-Modified and Amine-Functionalized Mwnt into Nanostructured Epoxy Systems

The development of high strength, ultra-light polymer composites has been improved by the addition of carbon nanotubes as a structural reinforcement. Nanotubes have attracted widespread interest, due to their exceptional mechanical, thermal and electrical properties. Specifically, their high aspect ratio and conductive and semi-conductive capabilities make them ideal fillers for conductive polymer systems. However, due to their highly stable graphitic structure, nanotubes are insoluble in water, organic solvents, and most monomers. When mixed into these media, nanotubes quickly aggregate and separate from solution, providing very little material improvement. In order to employ the excellent properties of nanotubes - multiwalled nanotubes (MWNT) have a tensile strength of 150 GPa, Young's Modulus of 1200 GPa, and aspect ratios exceeding 1000 - they must be covalently dispersed to achieve a homogenous system. Covalent dispersion, therefore, requires a chemical interaction between a surface-functionalized nanotube and the monomer. In this work, a study of electron-beam-irradiated (EB) and amine-functionalized MWNT was conducted to achieve a uniform, covalent dispersion throughout an epoxy-diamine network at low concentration. Characterization of modified and functionalized nanotubes was performed using thermogravimetric analysis (TGA), Raman Spectroscopy, and TEM, while nanotube-polymer composites were analyzed with SEM imaging; the extent of nanotube deformation, as well as their adhesion to the epoxy-amine network was determined through these techniques.