基于硼酸酯动态共价键双网络水凝胶在柔性传感器中的应用研究

Application of Double-network Hydrogel Based on Dynamic Borate Covalent Bond in Flexible Sensor

为了解决传统金属传感器机械柔性差和黏附性差的缺点,以海藻酸钠、硼砂和明胶为原料,采用一锅法制备了BSG双网络水凝胶,并对其流变学性能、机械性能、自愈合性能、黏附性能及电学性能等进行了评价。结果表明,BSG双网络水凝胶具有良好的机械性能,其最高拉伸率为660%,最大拉伸强度为50.2 kPa,最大韧性(断裂能)为799 kJ·m^(-3);BSG双网络水凝胶能够牢固黏附在多种有机和无机基底材料(纸杯、金属、玻璃、木头、橡胶、陶瓷、塑料和猪皮)表面,其中,BSG双网络水凝胶对木头的黏附强度和剥离强度最优,分别为58.3 kPa和12.2 kPa;将BSG双网络水凝胶组装成应变传感器后,在较宽的应变范围(0~400%)内具有较高的传感灵敏度(GF=1.68)及循环稳定性;BSG双网络水凝胶传感器可以将形变转换为电信号,将其黏附于人体不同部位能够实时监测手指、手腕、肘部和膝盖关节的弯曲运动以及微笑、眨眼、吞咽和说话的细微生理活动。

In order to solve the disadvantages of poor mechanical flexibility and adhesion of traditional metal sensors,taking sodium alginate,borax,and gelatin as raw materials,we prepared BSG double-network hydrogel by a one-pan method,and evaluated the rheological property,mechanical property,self-healing property,adhesion property,and electrical property.The results show that the BSG double-network hydrogel has good mechanical property with the highest stretch rate of 660%,tensile strength of 50.2 kPa,and toughness(breaking energy)of 799 kJ·m^(-3).BSG double-network hydrogel can firmly adhere to the surface of a variety of organic and inorganic substrate materials(paper cup,metal,glass,wood,rubber,ceramic,plastic,and pig skin),among which,BSG double-network hydrogel shows the best adhesion strength and peeling strength on wood,which are 58.3 kPa and 12.2 kPa,respectively.The strain sensor assembled by BSG double-network hydrogel has high sensitivity(GF=1.68)and cycle stability in a wide strain range(0-400%).BSG double-network hydrogel sensor can convert deformation into electrical signals,which can be attached to different parts of the body to monitor the bending movements of finger,wrist,elbow,and knee in real time,as well as the subtle physiological movements of smiling,blinking,swallowing,and articulation.