Fabrication of self-healing hydrogels with surface functionalized microcapsules from stellate mesoporous silica

Abstract

This report describes a dual-healing method for self-healing hydrogels, in which stellate mesoporous silica (STMS) was used to prepare surface-functionalized microcapsules. Firstly, polydopamine (PDA) was wrapped on STMS to obtain a functional microcapsule, which was loaded with healing agents and photoinitiators in STMS. Subsequently, poly(methyl-2-ureido-4[1H]-pyrimidinone-co-butyl acrylate) (P(MAUPy-co-nBA)) was modified on the surface of the microcapsules by click chemistry. The functionalized microcapsules have a dual-healing functionality of combining multiple hydrogen bonds on the surface and the healing agent from the interior. Rheological and tensile tests show that hydrogels with surface functionalized microcapsules have a higher healing efficiency. This method provides a simple and efficient dual-healing approach using surface functionalized microcapsules, which has promising application prospects for the design and synthesis of functional self-healing materials.