High-performance fiber strain sensor of carbon nanotube/thermoplastic polyurethane@styrene butadiene styrene with a double percolated structure

• Published in: Frontiers of materials science Vol. 16; no. 1; p. 220586
• Main Authors: XIANG, Dong, LIU, Libing, CHEN, Xiaoyu, WU, Yuanpeng, WANG, Menghan, ZHANG, Jie, ZHAO, Chunxia, LI, Hui, LI, Zhenyu, WANG, Ping, LI, Yuntao
• Format: Journal Article
• Language: English
• Published: Beijing Higher Education Press 01.03.2022; Springer Nature B.V
• Subjects: Butadiene; carbon nanotube; Carbon nanotubes; double percolated structure; Electrical resistivity; fiber; Load distribution (forces); Materials Science; nanocomposite; Percolation; Polyurethane resins; Research Article; Response time; Sensor arrays; Sensors; strain sensor; Styrenes; Urethane thermoplastic elastomers; nanocomposite; fiber; carbon nanotube; double percolated structure; strain sensor
• ISSN: 2095-025X; 2095-0268
• DOI: 10.1007/s11706-022-0586-8

In this work, a high-performance fiber strain sensor is fabricated by constructing a double percolated structure, consisting of carbon nanotube (CNT)/thermoplastic polyurethane (TPU) continuous phase and styrene butadiene styrene (SBS) phase, incompatible with TPU (CNT/TPU@SBS). Compared with other similar fiber strain sensor systems without double percolated structure, the CNT/TPU@SBS sensor achieves a lower percolation threshold (0.38 wt.%) and higher electrical conductivity. The conductivity of 1%-CNT/TPU@SBS (4.12×10 −3 S·m −1) is two orders of magnitude higher than that of 1%-CNT/TPU (3.17×10 −5 S·m −1) at the same CNT loading of 1 wt.%. Due to double percolated structure, the 1%-CNT/TPU@SBS sensor exhibits a wide strain detection range (0.2%-100%) and an ultra-high sensitivity (maximum gauge factor (GF) is 32411 at 100% strain). Besides, the 1%-CNT/TPU@SBS sensor shows a high linearity ( R 2 = 0.97) at 0%-20% strain, relatively fast response time (214 ms), and stability (500 loading/unloading cycles). The designed sensor can efficiently monitor physiological signals and movements and identify load distribution after being woven into a sensor array, showing broad application prospects in wearable electronics.