A High-Sensitive PDMS-Based sensor with a Wide Sensing Range by fabricating refined and reconstructable conductive network

Flexible and stretchable sensors are increasingly being developed to conformally attach to skin or organs for monitoring human activity. However, due to agglomerations of nanofiller, the preparation of a strain sensor for conductive elastic polymer with high sensitivity and wide detection range remains a major challenge. Herein, a conductive network is refined in PDMS/MWCNTs composites using an   elongational flow field. This well-formed 3D MWCNTs network endows the nanocomposite with a high sensitivity and wide detection range for strain deformation. Moreover, it exhibits excellent recovery and reconstruction capabilities during strain deformation, ensuring exceptional cyclic stability for the sensing material. In particular, the fabricated composite (4 wt% MWCNTs) with good tensile strength (8.1 MPa), exhibits high sensitivity (1151), a wide detection range exceeding 200 % strain, and good stable performance over 2000 stretch-release cycles under 30 % strain. Consequently, the strain sensor made from PDMS/MWCNTs composites can detect subtle actions and larger joint movements, exhibiting a good discriminative ability. In addition, the sensor is successfully applied to detect and recognize human lifting movements based on a big data model, highlighting the potential application in smart wearable devices. This work presents a new strategy for obtaining a highly sensitive PDMS-based sensor with a wide sensing range for human motion detection by fabricating an optimized conductive network.