Effect of CNT on the Physical and Electrical Properties of CNT/UHMWPE Nanocomposite Sensor

Abstract

Nano Composites Polymer represents a class of multifunctional sensors that can effectively respond to changes in electrical properties when subjected to external forces acting on their physical characteristics. The research aims to develop nanocomposite polymer sensors that can respond well and be easily molded. The experimental process involved mixing Ultra-high-molecular-weight polyethylene (UHMWPE) with 1%, 4%, and 7wt% of carbon nanotubes (CNT) using the hot pressing method, leading to remarkable improvements in the electrical and mechanical properties of the composite polymers. The distribution patterns of CNT at different weight ratios showed that 4 wt% exhibited a more desirable and uniform distribution. However, at 1 wt%, the amount of CNT was insufficient, resulting in scattering and disconnection. On the other hand, at 7 wt%, the CNT distribution appeared to be densely bundled in some areas, leading to detrimental effects on the mechanical and electrical properties, as well as the electrical percolation threshold of the composites. Regarding the mechanical properties test, significant improvements were found at 4 wt% for the tensile strength, but when the filler content exceeded 4 wt%, there was a reduction in the tensile strength of the CNT/UHMWPE composites. Additionally, the change in electrical resistance based on the physical characteristics was examined by varying the percentage of CNT added to UHMWPE through compression and bending tests. The compression tests were conducted using weights ranging from 0 to 10 kg, and the bending tests were performed with angles from 0° to 40° degrees. In terms of the test results, however, with 4% and 7% wt% CNT filler, the electrical resistance values could be successfully measured by a multimeter. The electrical percolation threshold was found to be very good at 4 wt%. For the compression testing results, the resistance values ranged from approximately 27.329 to 32.389 KΩ for the 4 wt% filler and from 0.504 to 0.552 KΩ for the 7 wt% filler. As for the bending testing, the resistance values ranged from approximately 4.019 to 4.044 KΩ for the 4 wt% filler and from 0.427 to 0.432 KΩ for the 7 wt% filler.