Abstract Submitted to the    NANOTUBE'04 Conference:

Polystyrene-grafted single-wall carbon nanotubes (SWNTs) were synthesized according to a method reported recently1. The polymer-grafted nanotubes were incorporated into a polystyrene matrix. Optical micrographs reveal better dispersion for functionalized nanotubes in polymer compared to unfunctionalized SWNTs. Static tensile tests and melt-state rheological studies were performed on the composites. The composite containing only 1% of functionalized SWNTs exhibit ~30% increase in tensile strength and ~ 50% increase in toughness compared to both pure polymer and the composites containing unfunctionalized nanotubes. Melt-state rheology performed on these composites indicates higher activation energies for terminal flow for the composites containing functionalized nanotubes. The low frequency-storage modulus was close to two orders of magnitude higher, and the divergence of dynamic viscosity observed at low frequencies suggests the onset of a percolated network-filler structure e ven at low nanotube loadings.

References
1. G. Viswanathan et al., J. Am. Chem. Soc., 125, 9258, 2003.