Thermoplastic Polyurethane/Carbon Nanotube Composites for Stretchable Flexible Pressure Sensors

Developing conductive polymer composites(CPCs) with high stretchabilityand high resistance response is a challenge in the field of flexiblesensing. In this study, porous CPCs with a microdome array on thesurface are prepared based on thermoplastic polyurethane (TPU) andcarbon nanotubes (CNTs). TPU/CNT composites are designed to be strainsensors and pressure sensors capable of monitoring external strainand pressure stimuli. Due to the excellent electrical properties ofcarbon nanotubes, the synergistic effect of composite surface microstructure,and an internal porous structure, the sensor has greatly improvedthe detection range and sensitivity of traditional sensors. The sensingproperties of CPC materials in terms of strain and pressure monitoringare perfectly balanced. The detection ranges of the strain sensorand pressure sensor are 0-160% and 0-55 kPa, respectively,and the highest sensitivity is gauge factor (GF) = 12.88 (90-160%)and sensitivity S = 0.08 (0-6.5 kPa), respectively.Based on the reversible change of the CNT conductive network undertensile/compression loading, the sensor has excellent stability anddurability during cyclic loading. In addition, the TPU/CNT compositesensors can monitor human movements, bending of composite components,and pressure positions, showing great application prospects in electronicskin, wearable smart devices, and human-computer interaction.

Automated summary

In this study, porous CPCs with a microdome array on the surface were developed based on TPU/CNT composites, which exhibit high stretchability and high resistance response. The sensors showed improved detection range and sensitivity due to the excellent electrical properties of CNTs and the synergistic effect of the composite surface microstructure and internal porous structure. These TPU/CNT composite sensors have excellent stability and durability during cyclic loading and can be applied in electronic skin, wearable smart devices, and human-computer interaction.