Largely Improved Tensile Properties of Chitosan Film via Unique Synergistic Reinforcing Effect of Carbon Nanotube and Clay

Abstract

In this work, a great synergistic effect of 2D clay platelets and 1D carbon nanotubes (CNTs) on reinforcing chitosan matrix has been observed for the first time. With incorporation of 3 wt % clay and 0.4 wt % CNTs, the tensile strength and Young's modulus of the nanocomposites are significantly improved by about 171 and 124%, respectively, compared with neat chitosan. This could be understood as due to the formation of much jammed fillers network with 1D CNTs and 2D clay platelets combined together, as indicated by rheological measurement. Our work demonstrates a good example for the preparation of high performance polymer nanocomposites by using nanofillers of different dimension together.

Synergic Effect of Clay on the Mechanical and Electrical Properties of SWCNT/Epoxy Composites

“…In addition, Tang et al investigated the synergistic effect of MWCNT/Na + -MMT on the tensile properties of a polymer nanocomposite and observed the maximum tensile strength can be found at an optimum MMT/MWCNT ratio of 3 wt% MMT to 0.2-0.6 wt% MWCNT. 12 Thus, for maximum tensile strength, Tang et al set their MMT/MWCNT ratio to 15, 9, and 5 for 0.2, 0.4, and 0.6 wt% of MWCNT, respectively.…”

“…12,15 CNTs tend to agglomerate due to strong van der Waals forces, which limit the dispersion of CNTs. Therefore, a suitable amount of stress is needed to break the CNT aggregates.…”

“…Tang et al proposed formation of 3D clay/CNT networks through the combination of 2D MMTs and 1D CNTs resulted in improved tensile properties. 12 Liu proposed that the incorporation of MMT increased viscosity, leading to difficulties in migration and reagglomeration. 15 However, the effect of MMT size has not yet been reported.…”

“…11 Similarly, Tang found a significant synergistic effect between clay and multi-walled CNTs (MWCNTs) for reinforcing the chitosan matrix. 12 By incorporating 3 wt% clay and 0.2-0.6 wt% CNTs, the tensile strength and Young's modulus of the nanocomposites improved significantly compared with that of neat chitosan. This effect can be explained by the formation of a filler network formed of 1D CNTs and 2D clay platelets combined together.…”

“…Consequently, engaging the synergistic effects of combined nanotubes and nanoclay in order to reinforce epoxy nanocomposites has been suggested as a way to improve CNT properties. Earlier reports revealed that the addition of clay to CNTs significantly improved the debundling of carbon nanotubes, resulting in fine dispersions in polymer matrix [11][12][13][14][15] Liu et al showed that the addition of clay significantly enhanced the electrical conductivity of single-walled CNT (SWCNT)/epoxy nanocomposites. 11 Similarly, Tang found a significant synergistic effect between clay and multi-walled CNTs (MWCNTs) for reinforcing the chitosan matrix.…”