Dai Tianyi, Lin Yankun, Yin Qing, Ji Qingmin, Wang Jingyi, Jia Hongbing
Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education, Nanjing University of Science and Technology, Nanjing 210094 China.
Hong Kong Centre for Cerebro-Cardiovascular Health Engineering, China.
J Colloid Interface Sci. 2025 Apr 15;684(Pt 1):575-585. doi: 10.1016/j.jcis.2025.01.031. Epub 2025 Jan 7.
Conductive hydrogel strain sensors demonstrate extensive potential in artificial robotics, human-computer interaction, and health monitoring, owing to their excellent flexibility and biocompatibility. Wearable strain sensors for real-time monitoring of human activities require hydrogels with self-adhesion, desirable sensitivity, and wide working range. However, balancing the high sensitivity and a wide working range remains a challenge. Herein, a marine coral exoskeleton inspired bicontinuous hydrogel (PAD-iP) for strain sensor was synthesized by in-situ copolymerization of acrylic acid (AA) and dimethylaminpropyl methacrylamide (DMAPMA) in the presence of poly(3, 4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) skeleton, using glycerol as water-retaining agent. Benefiting from the bicontinuous structure composed of electron-transported conductive, tough PEDOT:PSS skeleton and the ion-transported, flexible poly(AA-co-DMAPMA) hydrogel matrix, the strain sensor based on PAD-iP hydrogel struck an optimal balance between ultrahigh sensitivity (gauge factor up to 1049) and a broad sensing range (strain of 0-600 %). The strain sensors could be adhered directly to skin to monitor full-range human activities, physiological activities and physical vibrational signals of the local environment. The strain sensor also exhibited robustness and stable sensing properties across a wide temperature range (-20 ∼ 40 ℃). This work offers a fresh inspiration for preparation of high-performance hydrogel strain sensors.
导电水凝胶应变传感器因其出色的柔韧性和生物相容性，在人工机器人技术、人机交互和健康监测方面展现出广泛的潜力。用于实时监测人体活动的可穿戴应变传感器需要具有自粘性、理想灵敏度和宽工作范围的水凝胶。然而，平衡高灵敏度和宽工作范围仍然是一个挑战。在此，通过在聚（3,4-乙撑二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT:PSS）骨架存在下，以甘油作为保水剂，将丙烯酸（AA）和二甲基氨基丙基甲基丙烯酰胺（DMAPMA）原位共聚，合成了一种受海洋珊瑚外骨骼启发的用于应变传感器的双连续水凝胶（PAD-iP）。得益于由电子传输导电、坚韧的PEDOT:PSS骨架和离子传输、柔性的聚（AA-co-DMAPMA）水凝胶基质组成的双连续结构，基于PAD-iP水凝胶的应变传感器在超高灵敏度（应变片系数高达1049）和宽传感范围（0-600%应变）之间实现了最佳平衡。该应变传感器可直接粘附在皮肤上，以监测人体的全范围活动、生理活动以及局部环境的物理振动信号。该应变传感器在较宽的温度范围（-20~40℃）内还表现出稳健性和稳定的传感性能。这项工作为制备高性能水凝胶应变传感器提供了新的灵感。
