High-strength polyurethane elastomer with recyclable room-temperature self-healing on the basis of multiple hydrogen bonds/aromatic disulphide bonds

Abstract

In order to explore new high-strength polymer materials that can achieve self-healing of damage under more mild conditions, the high-strength room temperature self-healing polyurethane elastomers with multiple hydrogen bonds/aromatic disulphide bonds (PU_PIPMD) were constructed by using the strategy of multiple repair networks. Through the interaction between the carbamate group (-NH-C(=O)-O-), pyridine and urea group (-NH-CO-NH-) to form a multiple of different strength hydrogen bond, the reversible covalent bond-disulphide bond (-S-S-) was introduced into the molecular chain at the same time to build the target amorphous structure products. The prepared room temperature self-healing polyurethane elastomer had outstanding mechanical properties with strain-strengthening behaviour. In addition, it also exhibits strain-strengthening behaviour. After 48 h of static repair at room temperature, the tensile strength, elongation at break, and toughness of prepared polyurethane elastomer can be well restored, with a synchronous self-healing efficiency of over 80%. Achieving a dual improvement in mechanical strength and room temperature self-healing performance. And further enhanced the service life and reusability of the polyurethane elastomer material.