Double regulation of conductivity by adhesive hydrogel based on catechol‐modified sodium alginate /acrylamide hydrogel with silver ions

Abstract

AbstractThe purpose of this study is to explore how to control the conductivity of gel conveniently and effectively through experiments. First, a kind of acrylamide‐based composite with adhesion and conductivity adjustment was prepared by adding silver ions and silver monomers to the gel in one step. The semi interpenetrating network structure formed by the molecular chain of polyacrylamide and catechol modified sodium alginate in the composite is cross‐connected with silver ions to form a double network structure. This change of network structure not only makes the structure of gel more stable, but also brings extraordinary conductivity. Secondly, different types of conductive ions and organic solutions were added to the gel system. Electrochemical impedance spectroscopy showed that the addition of silver enhanced the conductivity of the material; When NaNO3 is used to replace water molecules in PAM, the ionic conductivity can be increased by 75.3% (from 2.44 × 10−5 to 20.8 × 10−5 mscm−1). When PDA/PAM was soaked in AgNO3, the ionic conductivity increased in the range of 10.4% ~ 674%. It provides a novel strategy for controlling the conductivity of composite materials.