Strain Sensitivity of Carbon Nanotubes Modified Cellulose

Nanostructured cellulose was modified by different concentration and volume of dispersed multi-walled carbon nanotube (MWCNT) and double-walled carbon nanotube (DWCNT) solutions and its electrical properties were studied. The resulting flexible cellulose films have an electrical conductivity sensitive to changes in CNT concentration and immersion time in solution. The conductivity increases with increasing immersion time and volume and concentration of dispersed solutions; the conductivity for bacterial cellulose (BC) pellicles modified with DWCNT was increased from 0.034 S.cm(-1) to 0.15 S.cm(-1) and for BC pellicles modified with MWCNT it was increased from 0.12 S.cm(-1) to 1.6 S.cm(-1) when the immersion time was increased from 24 h to 72 h. These results are significantly higher than in previously reported work [1]. The effect of strain on the resistance during application of tensile force is shown for a simple strain gauge employing cellulose with incorporated DWCNTs. The electrical resistance of the films displays a high sensitivity to strain. It seems that this sensitivity depends on the modifying conditions, where BC pellicles which are modified in a dispersed solution with a higher concentration of CNTs show larger changes in resistance with the changes in fractional extension (C) 2011 Published by Elsevier Ltd.