CNT-Br/PEDOT:PSS/PAAS three-network composite conductive hydrogel for human motion monitoring
Abstract
Conductive hydrogels are promising flexible conductors for human motion monitoring. However, this kind of wearable strain sensor has often shown weak mechanical properties. To overcome the inherent mechanical weakness and improve the electrical conductivity, CNT-Br/PEDOT:PSS/PAAS triple-network penetrating conductive hydrogels (CBP) are fabricated. The n-butylimidazolium bromide salt-functionalized MWCNTs (CNT-Br) as conductive fillers form a three-dimensional conductive path through the crosslinking agent XR-100, penetrating with the skeleton of crosslinking sodium polyacrylate. The conductive liquid PEDOT:PSS is further evenly dispersed in the penetrating double network to further enhance the electrical conductivity of the hydrogels. CNT-Br without obvious agglomeration significantly improved the thermal stability and mechanical properties of CBP. Moreover, CNT-Br enabled the PEDOT:PSS components to be more evenly dispersed in the PAAS matrix. Due to the good conductive paths inside the hydrogels, the maximum electrical conductivity (CBP10) increases to 10.35 mS cm−1, which is 415% higher than that of pure P1. Our work provides a method to prepare conductive hydrogels with high electrical conductivity and excellent mechanical properties, which can be used for human joint motion detection.