Hierarchical MXene@PBA nanohybrids towards high-efficiency flame retardancy and smoke suppression of robust yet tough polymer nanocomposites at ultra-low additions

Developing efficient flame-retardant MXene-based polymeric materials with enhanced mechanical properties has been a huge challenge. Herein, Prussian blue analogues (PBAs) were used to modify the surface of MXene nanosheets via an electrostatic self-assembly method to construct hierarchical MXene-based nanohybrids (MXene@PBA). Then, MXene@PBA was incorporated into the epoxy matrix to fabricate high-performance epoxy nanocomposites (EP-MXene@PBA). The study indicates that hierarchical MXene@PBA exhibits excellent dispersion performance in the epoxy matrix. Notably, MXene@PBA results in high-efficiency flame retardancy and smoke suppression for epoxy nanocomposites at ultra-low additions. What is very surprising is that only 1.0 wt% MXene@PBA can easily enhance the UL-94 rating of EP-1.0%MXene@PBA to V0. Meanwhile, the peak heat release rate (pHRR), total smoke production (TSP), and peak CO production rate (pCO) are remarkably reduced by 36.70%, 34.28%, and 43.48%, compared to those of the pristine epoxy resin, respectively. Furthermore, the 1.0 wt% MXene@PBA nanohybrids can enhance the flexural and impact strengths of EP-1.0%MXene@PBA. This work provides a feasible strategy for the creation of multifunctional MXene derivatives and their polymeric nanocomposites and holds great promise for many industrial applications.