Pangolin Scale Inspired Healable, Recyclable, and Mechanically Robust Supramolecular Waterborne Polymer Networks

Abstract

Although healable waterborne polymers have attracted significant attention in recent years due to their environmentally friendly properties, the inferior mechanical properties still hinder their further propagation. Inspired by the micro-structure of pangolin scales, herein, a novel supramolecular waterborne polymer network (SWPN) named SWPUMA-SPPEK10 is proposed in this study. This polymer is fabricated by complexing sulfonated poly(phthalazinone ether ketone) (SPPEK) with acylsemicarbazide (ASC) containing cationic supramolecular waterborne polyurethane (SWPUMA) in an aqueous solution followed by a hot-pressing process. Due to the synergistic effects of ASC, electrostatic interactions, and the SPPEK nanoparticles, SWPUMA-SPPEK10 exhibited remarkable mechanical properties with a tensile strength of 55.19 MPa, and a toughness of 305.93 MJ m⁻³. The rich dynamic supramolecular interactions within polymer chains also imparted it with excellent healability and recyclability. This biomimetic structural design provides a new insight for constructing high-performance healable waterborne polymers with robust mechanical properties and recyclability, which may play a critical role in mitigating global environmental pollution.