Electrical conductivity and crystalline morphology of single-walled carbon nanotube/linear polyethylene nanocomposites

POLY 408

Keesu Jeon, keesu@eng.fsu.edu1, Rufina G. Alamo, alamo@eng.fsu.edu1, Lloyd Lumata, lumata@magnet.fsu.edu2, Takahisa Tokumoto, tokumoto@magnet.fsu.edu2, and James S. Brooks2. (1) Department of Chemical and Biomedical Engineering, Florida A&M University and Florida State University College of Engineering, 2525 Pottsdamer St., Tallahassee, FL 32310, (2) Department of Physics and National High Magnetic Field Laboratory, Florida State University, Tallahassee, FL 32310
SWCNT/LPE nanocomposites were prepared in a NT concentration range from 0.02 to 8 wt %. A good dispersion of the nanotubes was obtained after sonication in 1,2 dichlorobenzene, and mixing with a solution of the LPE at high temperature followed by rapid quenching in cold methanol. The dispersion of the SWCNT in the polymer matrix was monitored by the presence of isolated NTs in SEM images and by analysis of their Raman spectra. As a function of increasing concentration of SWCNT the percolation threshold for electrical conductivity is found at about 0.13 wt %. This value is significant as it is the lowest concentration ever reported for electrical percolation in CNT/PE nanocomposites. In reference to pure LPE, the nucleation density of SWCNT/LPE nanocomposites displayed a significant increase even at the lowest SWCNT concentrations. Consequently, the banded spherulitic morphology of LPE undergoes a drastic change in the nanocomposites.