A mechanically strong conductive hydrogel reinforced by diaminotriazine hydrogen bonding

Over the past decades, the urgent need for high strength conductive hydrogels in diverse applications has motivated an unremitting effort to combine the improved mechanical properties of hydrogels with conductive performances. In this work, high strength conductive hydrogels intensified with intermolecular hydrogen bonding are fabricated by in situ mixing poly(2-vinyl-4,6-diamino-1,3,5-triazine-co-polyethylene glycol diacrylates) (PVDT-PEGDA) hydrogels with poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT/PSS). The conductive hydrogels in deionized water exhibit high mechanical performances with compressive strength and tensile strength in the range of 7.58-9.52 MPa and 0.48-1.20 MPa respectively, which are ascribed to the intermolecular hydrogen bonding interactions of diaminotriazine-diaminotriazine (DAT-DAT) in the network. Meanwhile, adding PEDOT/PSS can significantly increase both the specific conductivities and equilibrium water contents of the hydrogels. These cytocompatible conductive hydrogels may have a great potential to be used as electrical stimuli responsive soft biomaterials.