Facile synthesis of conductive PVA/HA/PEDOT composite hydrogel for human motion monitoring

Conductive hydrogel has attracted interests in developing flexible and wearable sensors due to the high electrical conductivity and exceptional mechanical property. Classic conductive polymers such as poly(3,4ethylenedioxythiophene) (PEDOT) are considered as one of the most promising conductive polymers with excellent chemical stability and easy processability. However, realizing excellent mechanical stability and electrical conductivity of processing sensors is still challenging. In this study, a facile and one-step strategy for synthesizing conductive PEDOT-based composite hydrogel was developed by in situ polymerization combining with freeze-thaw cycles, using EDOT as monomer and ammonium persulfate (APS) as initiator. Following this, a porous PVA/HA/PEDOT (PHP) composite hydrogel was firstly prepared by incorporating conductive hyaluronic acid (HA) and polyvinyl alcohol (PVA) into PEDOT polymerization process. The incorporation of HA contributed to the improvement of the mechanical performance and electrical conductivity of PHP hydrogels. The PHP1 hydrogel with 1 wt% EDOT content possessed the good electrical conductivity of about 1.97 S/m. This study introduced an innovative method for creating such PEDOT-based strain sensors, broadening potential application in wearable and flexible sensors.