Preparation of desirable plant protein-based adhesive via bioinspired Laponite-assisted organic-inorganic copolymerization

Abstract

The preparation of plant protein-based adhesives is one of the potential strategies to mitigate environmental pollution. In this work, the organic-inorganic copolymerization of calcium phosphate oligomer and soy protein was performed by adopting the concept of organic-inorganic polymerization and the physics of polymer adsorption to eliminate the interphase boundary, preparing an adhesive layer with continuous and uniform network structure without using chemical cross-linkers. The participation of ionic and hydrogen bonds improved the mechanical strength. In addition, the Laponite with anisotropic charge distribution was introduced into the cross-linking network to increase the density and cohesion of cross-linking and further improve the bonding performance without complex chemical synthesis. The modified adhesive had an optimum wet shear strength of 1.01 MPa, and excellent water resistance (85.7 % residue rate). The modified adhesive shows good cell compatibility plus flame retardancy. Overall, this biomimetic study has excellent promises for the design of protein-based adhesives with desirable properties for engineering applications.