Physical and Dielectric Properties of Fullerene-Containing Polyurethane
American Chemical Society
A series of C60 fullerene-polyurethane (C60-PU) nanocomposites were prepared from a simple reaction between a diisocyanate end-capped prepolymer and increasing loadings of polyhydroxylated fullerenes (fullerenols) in a solvent mixture of THF/DMF. The prepared nanocomposites were characterized using standard techniques: FT-IR, Dynamic Mechanical Analysis (DMA) and Dielectric Spectroscopy (DS). The dielectric spectra of the prepared samples were determined over the frequency range 0.1 Hz - 3 MHz at fixed temperatures from -150 to 180 ˚C. The values of real dielectric permittivity, e', of the prepared C60(OH)x are much higher than that of the C60 due to the polarizable OH groups attached to the surface of the C60 fullerene cages. Furthermore, the e' of fullerene-PU nanocomposites increases with increasing fullerenol loading due to polarization contributions of the unreacted hydroxyl groups in C60(OH)x. DMA and DS showed loss peaks at approximately -50 0C corresponding
to the glass transition temperatures, Tg, of prepared films.
Hanaa M. Ahmed, Steven Stevenson, Mohammad K. Hassan, Kenneth A. Mauritz, and Janice Paige Phillips (2011).
Physical and Dielectric Properties of Fullerene-Containing Polyurethane. Presented at American Chemical Society, Anaheim, CA.