Self-healing of glucose-modified polyurethane networks facilitated by damage-induced primary amines

Abstract

Living organisms utilize metabolic processes to achieve adaptive, reproductive, and self-healing functions, which require dynamic and precise control of sequential chemical events. Since traditional synthetic materials do not possess these functions, there is an ongoing quest for the development of self-healing attributes. This study reports self-healing of crosslinked polyurethane networks by damage-induced formation of primary amines. Deliberately modified with methyl α-D-glucopyranoside (MGP) and catalyzed by zinc acetate (Zn(OAc)₂), polyurethane (PUR) networks are capable of restoring mechanical properties upon mechanical damage. Self-repair is initially driven by entropic shape recovery facilitating interfacial contacts in damaged areas, followed by covalent reformation of cleaved bonds. Amine functionalities resulting from mechanical damage facilitate covalent re-bonding to form urea linkages responsible for recovery of mechanical properties.