Iron-loaded polydopamine nanospheres act as nontoxic and highly efficient flame retardants in epoxy resins via free radical scavenging and catalytic charring actions.

Some crop by-products are considered to be promising materials for the development of novel biobased products for industrial applications. The flammability of these alternatives to conventional materials is a constraint to expanded applications. Polylactide (PLA) composites containing a combination of oxidized corn pith fiber (OCC) and a biobased flame retardant (PA-THAM) have been prepared via an in situ modification method. SEM/EDS, FTIR and TGA were performed to establish that PA-THAM was coated onto the surface of OCC. The mechanical properties, thermal stability and fire behavior of PLA-based biocomposites were investigated. The incorporation of 5 phr PA-THAM imparted biocomposite good interfacial adhesion and increased decomposition temperature at 10% mass loss by 50 °C. The flame retardant properties were also improved, as reflected by an increased LOI value, a UL-94 V-2 rating, reduction of PHRR, and increased formation of char residue. Therefore, the introduction of 5 phr PA-THAM can maintain a good balance between flame retardancy and mechanical properties of this PLA/OCC system.

Understanding plastic deformation behaviour is key to optimising the mechanical properties of nano-polycrystalline layered composites. This study employs the molecular dynamics (MD) simulation to comprehensively investigate the effects of various factors, such as grain sizes, strain rates, and the interlayer thicknesses of the intermetallic compounds (IMCs), on the plastic deformation behaviour of nano-polycrystalline Al/Mg layered composites. Our findings reveal that the influence of grain size on deformation behaviour is governed by the strain rate, and an increase in grain size is inversely proportional to yield stress at low strain rates, whereas it is positively proportional to tensile stress at high strain rates. Moreover, an optimal thickness of the intermediate layer contributes to enhanced composite strength, whereas an excessive thickness leads to reduced tensile strength due to the fewer grain boundaries (GBs) available for accommodating dislocations. The reinforcing impact of the intermediate IMCs layer diminishes at excessive strain rates, as the grains struggle to accommodate substantial large strains within a limited timeframe encountered at high strain rates. The insights into grain sizes, strain rates, and interlayer thicknesses obtained from this study enable the tailored development of nanocomposites with optimal mechanical characteristics.