Highly Stretchable and Sensitive Single-Walled Carbon Nanotube-Based Sensor Decorated on a Polyether Ester Urethane Substrate by a Low Hydrothermal Process

Abstract

We report a highly stretchable sensor with low-concentration (1.5 wt %) single-walled carbon nanotubes (SWCNTs) on flexible polyether ester urethane (PEEU) yarn, fabricated using a low hydrothermal process at 90 °C. Although SWCNTs restrict the PEEU polymer chain mobility, the resulting ductility of our nanocomposites reduces only by 16.5% on average, initially from 667.3% elongation at break to 557.2%. The resulting electrical resistivity of our nanocomposites can be controlled systematically by the number of hydrothermal cycles. A high gauge factor value of 4.84 is achieved at a tensile strain below 100%, and it increases up to 28.5 with applying a tensile strain above 450%. We find that the piezoresistivity of our nanocomposite is sensitive to temperature variations of 25–85 °C due to the hopping effect, which promotes more charge transport at elevated temperatures. Our nanocomposites offer both a high sensitivity and a large strain sensing range, which is achieved with a relatively simple fabrication technique and low concentration of SWCNTs.

Multiscale Analysis of the Highly Stretchable Carbon−Based Polymer Strain Sensor

“…Despite the fact that carbon−based polymer sensors have received widespread attention, current research has focused mainly on the manufacture of the device and the sensing behavior [ 11 , 12 , 13 , 14 ] while research on its sensing mechanism is limited. In the initial research, an analogy method was proposed to quantitatively describe the electromechanical behavior of silicone rubber filled with CNPs, but the sensing mechanism was not involved [ 15 ].…”