Fabrication of conductive composite hydrogels with excellent pressure sensitivity via in situ polymerization of ternary DES

•CS/CNT/PAM-U composite hydrogels have excellent pressure sensitivity and can be used to prepare pressure sensors.•CS/CNT/PAM-U composite hydrogel has good electrical conductivity.•CS/CNT/PAM-U composite hydrogel has good self-healing properties. In this paper, choline chloride, acrylamide and urea were used to prepare deep eutectic solvent (DES), and CS and N-CNTs were used as fillers to prepare composite hydrogels through in-situ polymerization. Using FTIR and SEM characterization analysis, the results showed that the pressure sensitivity and conductivity of the composite hydrogel were significantly improved after adding CS and N-CNTs. When the filler content reaches the highest level, the pressure sensitivity increases by 13 times and the conductivity reaches 2.05 mS/cm, which is 14.7 times that of the hydrogel without filler. This study provides a preparation method for composite hydrogels with excellent conductive properties and pressure sensitivity.