Targeted assembly of hierarchical sea-urchin inspired NiPS@LDH architecture for enhanced toughness, wear-resistance and fire-safety of epoxy composites

Abstract

Epoxy resin (EP) is a versatile material widely used in fields such as electronic encapsulation, coatings, adhesives, and composites. The targeted assembly of nanomaterials to optimize the flame retardancy, mechanical properties, and interfacial properties of composite materials is a prominent research hotspot in the field of EP. Therefore, a hierarchical sea-urchin inspired architecture (NiPS@LDH), based on layered double hydroxide (LDH) nanosheets grown on nickel phyllosilicate (NiPS), was rationally constructed as a functional filler for EP with a view to building high-performance EP composites. The addition of 1 wt% NiPS@LDH increased the tensile strength, modulus of elasticity, and elongation at break of EP by 44.1 %, 27.6 %, and 66.2 %, respectively, showing excellent strengthening and toughening effects. Meanwhile, under dry friction conditions, the wear rate of the composites was 0.86 mm3·N−1·m−1, reduced by 87.8 % compared to that of pure EP, indicating excellent wear resistance. Besides, the pHRR, THR, pSPR, TSP, pCO and pCO₂ of EP/NiPS@LDH-3 composites were found to be significantly reduced by 54.0 %, 61.9 %, 50.7 %, 54.4 %, 51.2 %, and 58.2 %, respectively. The LOI value of the composites increased to 26.4 %, and the maximum weight loss (Rmax) was reduced by 27.7 %. This study provides an innovative strategy for the targeted assembly of nanomaterials, paving the way for the preparation of high-performance EP nanocomposites.