Flexible strain sensors based on carbon nanotubes/polydimethylsiloxane composites with a segregated structure prepared by sustainable emulsion method

作者：Bin Jia, Zhouyu Liu, Dong Xiang, Libing Liu, Haoming Sun, Yuanpeng Wu, Mulan Mu, Bin Wang, Chunxia Zhao, Hui Li · 发表于：Polymer Engineering and Science · 年份：2024 · DOI：10.1002/pen.27059 · 被引用次数：8 · 研究领域：Advanced Sensor and Energy Harvesting Materials、Conducting polymers and applications、Gas Sensing Nanomaterials and Sensors

Abstract Flexible strain sensors have been widely used in many fields because of their excellent adaptability and flexibility. Nonetheless, creating these sensors through simple methods that achieve a low percolation threshold and high sensitivity continues to pose a challenge. In this paper, a segregated structure was realized in a carbon nanotube/polydimethylsiloxane (CNT/PDMS‐S) strain sensor by a sustainable emulsion method that involved the mixing cellulose nanocrystals (CNCs), CNTs, PDMS and water. The incorporation of CNC improved the stability of CNTs in aqueous suspension. Consequently, The CNT@CNC nanocomposites were strategically placed in the gaps between the PDMS microspheres, creating a segregated structure. The segregated structure notably lowered the percolation threshold of the composite to 0.49 wt%. Moreover, we found that the CNT/PDMS‐S sensor containing 1.5 wt% CNTs showed excellent sensing performance, which not only had a wide strain measurement range and could adapt to the strain change from 0% to 70%, but also had high sensitivity with a gauge factor (GF) of 290 at 70% strain. Meanwhile, the sensor had an excellent linear response ( R 2 ≥ 0.96) and can monitor the minimum strain of 0.1%. The proposed sensor demonstrated excellent response when applied to sense wrist movement, facial movement and closure, and syllable recognition. Highlights Strain sensors with a segregated structure were realized by a sustainable method. The segregated structure greatl...