Grafting Polymer Onto Carbon Nanotubes And Its Use In Modification Of Polymer

Since the discovery in 1991, Carbon nanotubes have encouraged the development of new nanotechnologies because of their outstanding electronic, mechanical and thermal properties. However,carbon nanotubes are large molecules with thousands of carbon atoms in an aromatic delocalized system and strong inter tube van der Waals attraction, they are practically insoluble in all solvents and, consequently, their applications are limited.In this artical, Dithioester compounds was grafted onto the surface of carbon nanotubes as chains transfer agent of RAFT (reversible-addition-fragmentation chain transfer)polymerization. Then copolymer of styrene (St) and methyl methacrylate (MMA) were grown from the surface of carbon nanotubes via RAFT polymerization. It was found that after wrapped with polymer chains, the dispersibility and stabilization of CNTs in common solvents were improved greatly.And a series of carbon nanotube/ploymer nanocomposites were prepared, mechanical property of nanocomposites and dispersion of carbon nanotubes in polymer matrix were studied, the results show that mechanical property of polymer have enhanced by the additon of carbon nanotubes, and carbon nanotubes have a good dispersion in polymer matrix.FTIR was used to determine the qualitiy of grafted carbon nanotubes, TEM images of the carbon nanotubes provided a direct evidence for the formation of a core-shell nanostructure. SEM images are used to check the dispersibility of carbon nanotubes in composites.