Polymeric and Soft Materials Laboratory, School of Chemical Engineering, Advanced Institute of Materials Science, Changchun University of Technology, Changchun 130012, P.R. China.
ACS Appl Mater Interfaces. 2023 Jun 21;15(24):28993-29003. doi: 10.1021/acsami.3c05208. Epub 2023 Jun 7.
Stretchable hydrogels as landmark soft materials have been efficiently utilized in the field of wearable sensing devices. However, these soft hydrogels mostly cannot integrate transparency, stretchability, adhesiveness, self-healing, and environmental adaptability into one system. Herein, a fully physically cross-linked poly(hydroxyethyl acrylamide)-gelatin dual-network organohydrogel is prepared in a phytic acid-glycerol binary solvent via a rapid ultraviolet light initiation. The introduction of gelatin as the second network endows the organohydrogel with desirable mechanical performance (high stretchability up to 1240%). The presence of phytic acid not only synergizes with glycerol to impart environment-tolerance to the organohydrogel (from -20 to 60 °C) but also increases the conductivity. Moreover, the organohydrogel demonstrates a durable adhesive performance toward diverse substrates, a high self-healing efficiency through heat treatment, and favorable optical transparency (transmittance of 90%). Furthermore, the organohydrogel achieves high sensitivity (gauge factor of 2.18 at 100% strain) and rapid response time (80 ms) and could detect both tiny (a low detection limit of 0.25% strain) and large deformations. Therefore, the assembled organohydrogel-based wearable sensors are capable of monitoring human joint motions, facial expression, and voice signals. This work proposes a facile route for multifunctional organohydrogel transducers and promises the practical application of flexible wearable electronics in complex scenarios.
作为具有里程碑意义的软材料，可拉伸水凝胶已在可穿戴传感设备领域得到有效利用。然而，这些软水凝胶大多无法将透明度、可拉伸性、粘附性、自修复性和环境适应性集成到一个系统中。在此，通过快速紫外光引发，在植酸-甘油二元溶剂中制备了完全物理交联的聚（羟乙基丙烯酰胺）-明胶水双网络有机水凝胶。明胶的引入赋予了有机水凝胶理想的机械性能（高达 1240%的高拉伸性）。植酸的存在不仅与甘油协同作用，赋予有机水凝胶环境耐受性（-20 至 60°C），还提高了导电性。此外，该有机水凝胶对各种基底具有持久的粘附性能、通过热处理实现的高自修复效率以及良好的光学透明度（透光率为 90%）。此外，该有机水凝胶具有高灵敏度（应变 100%时的灵敏度系数为 2.18）和快速响应时间（80ms），可检测微小（检测下限低至 0.25%应变）和大变形。因此，组装的基于有机水凝胶的可穿戴传感器能够监测人体关节运动、面部表情和声音信号。这项工作为多功能有机水凝胶换能器提出了一种简便的途径，并有望将柔性可穿戴电子产品应用于复杂场景。
