Application of adhesive controllable galactomannan hydrogel initiated by aluminum ions at room temperature in flexible sensors

Abstract

Galactomannan has the advantages of abundant resources and renewable raw materials. The development of conductive galactomannan hydrogels with reversible adhesion is important for improving their application in flexible sensors. However, the energy consumption of the polymerization process and the challenges of removing associated with removing traditional adhesive hydrogels limit their applications. In this paper, the double network Al3+- TA/GG-PAM phenylboronic acid supramolecular hydrogel with borate ester bond dynamic crosslink and MBA (N, N′-methylene bis acrylamide) covalent crosslink was simply and rapidly prepared by blending phenylboronic acid with metal ion Al3+, tannic acid (TA), galactomannan (GG) and polyacrylamide (PAM) chain.The dynamic cross-linking of borate ester bonds can control the catechol group, enabling the achievement of a reversible viscosity/debonding transition. The double network structure provides a tough and stable electronic transmission network for aluminum ions, thus showing electrical conductivity (4.9mS·cm−1). Obviously, the strategy of preparing multifunctional hydrogels based on the rapid catalytic system of catechol aluminum ions and the strategy of borate ester bond controlling catechol groups realizing the reversible conversion of viscosity/debonding will provide a new way for the design and development of advanced skin sensors.