Ding Hongyao, Wang Bingyao, Yang Xu, Liu Jie, Sang Wei, Li Xuewen, Wen Yuefang, Li Hui, Shen Xiaodong
College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China.
Key Laboratory for Light-weight Materials, Nanjing Tech University, Nanjing 210009, China.
Int J Biol Macromol. 2025 Feb;291:139183. doi: 10.1016/j.ijbiomac.2024.139183. Epub 2024 Dec 26.
Conductive hydrogels have great potential for applications in flexible wearable sensors due to the combination of biocompatibility, mechanical flexibility and electrical conductivity. However, constructing conductive hydrogels with high toughness, low hysteresis and skin-like modulus simultaneously remains challenging. In the present study, we prepared a tough and conductive polyacrylamide/pullulan/ammonium sulfate hydrogel with a semi-interpenetrating network. Ammonium sulfate promoted the formation of low-energy-dissipating motifs between polymer chains, reinforcing the gel matrix and resulting in excellent mechanical properties, including a high stretchability of 2063 %, a high strength of 890 kPa, and a high toughness of 4268 kJ/m. The hydrogen bonds formed within the network endowed the gels with low-hysteresis under deformation. The unique semi-interpenetrating network structure provided the gels with a tissue-like low modulus. Additionally, the resulting hydrogels exhibited a high conductivity of 2.39 S/m and excellent anti-freezing properties, making them suitable for flexible strain sensors. These sensors demonstrated high sensitivity over a broad strain window of 0.1-1500 %, enabling the detection of various human motions and the recognition of different languages. These findings emphasize the potential of the composite hydrogels as wearable strain sensors for flexible devices.
由于具有生物相容性、机械柔韧性和导电性，导电水凝胶在柔性可穿戴传感器领域具有巨大的应用潜力。然而，同时构建具有高韧性、低滞后性和类皮肤模量的导电水凝胶仍然具有挑战性。在本研究中，我们制备了一种具有半互穿网络结构的坚韧且导电的聚丙烯酰胺/支链淀粉/硫酸铵水凝胶。硫酸铵促进了聚合物链之间低能量耗散基序的形成，增强了凝胶基质，从而产生了优异的机械性能，包括2063%的高拉伸性、890 kPa的高强度和4268 kJ/m的高韧性。网络内形成的氢键使凝胶在变形时具有低滞后性。独特的半互穿网络结构赋予凝胶类组织的低模量。此外，所得水凝胶表现出2.39 S/m的高导电性和优异的抗冻性能，使其适用于柔性应变传感器。这些传感器在0.1 - 1500%的宽应变窗口内表现出高灵敏度，能够检测各种人体运动并识别不同语言。这些发现强调了复合水凝胶作为柔性设备可穿戴应变传感器的潜力。
