Bioinspired hierarchical interface design for improved mechanical and safety properties in energetic polymer composites

Abstract

Weak interfacial interaction and poor surface wettability always restrict and weaken the performances of energetic composites. Conventional surface modifications can hardly achieve a desired result, due to the inadequacy for solving the interfacial incompatibility. We here demonstrated bioinspired hierarchical-structured 2,6-diamino-3,5-dinitropyrazine-1-oxide particles through in situ “grafting from” polymerization of hyperbranched polyurethane (HBPU) on polydopamine surface. Benefiting from the enhanced interfacial interaction and surface wettability which facilitated mechanical performance, the final results revealed that a remarkable mechanical enhancement was successfully achieved through this way. Meanwhile, improved safety performance was gained, and the impact sensitivity was reduced to a large extent which was ascribed to the cushioning and protective effects of HBPU shells with soft segments. We believe this approach of constructing bioinspired hierarchical interface aiming at solving low surface wettability and weak interface will shed light on the design and preparation of high-performance composites through a novel and effective way.