Mechanical properties of chitosan/CNT microfibers obtained with improved dispersion

Composite fibers composed of chitosan and single-wall carbon nanotubes (CNTs) have been fabricated with a wet spinning method. The dispersion was improved by sonic agitation of CNTs in a chitosan solution and then centrifugation to remove tube aggregates and residual catalyst. Raman spectroscopy was used to measure the CNT state in solution, the form of the microfibers, and the cross-linking effect. The mechanical behavior was investigated with dynamic mechanical analysis (DMA). Mechanical testing showed a dramatic increase in Young's modulus for the chitosan/CNT composite fibers fabricated using the improved dispersion method. The wet mechanical properties were also improved by addition of CNT while the pH sensitivity of the microfibers was largely unchanged.