Self-assembling nacre-like high-strength and extremely tough polymer composites with new toughening mechanism

Achieving high strength, deformability and toughness in polymers is important for practical industrial applications. This has remained challenging because of the mutually opposing effects of improvements to each of these properties. Here, a self-assembling nacre-like polymer composite is designed to achieve extremely tough with increasing strength. This special design significantly improved polymer's mechanical properties, including an ultra-high fracture strain of 1180%, a tensile strength of 55.4 MPa and a toughness of 506.9 MJ/m³, which far exceed the highest values previously reported for polymer composites. This excellent combination of properties can be attributed to a novel toughening mechanism, achieved by the synergy of the domain-limiting effect of metallic glass fragments with the strain-gradient-induced orientation and crystallisation within the polymer during stretching. Our approach opens a promising avenue for designing robust polymer materials in armour and aerospace engineering for a range of innovative applications.