MXene-wrapped zinc hydroxystannate nanocubes toward reducing the heat, smoke and toxicity hazards of ABS resin

Acrylonitrile–butadiene–styrene (ABS) composites with less smoke and toxicity hazards (e.g., HCN and NO_x) emission are highly demanded. As a common smoke suppressant, zinc hydroxystannate (ZHS) has been used in various polymers, while the high content, special cube shape and agglomeration restrict its development. To solve these problems, MXene (Ti₃C₂T_x) nanosheets were utilized to wrap ZHS nanoparticles (Ti₃C₂T_x-PDA-ZHS) to improve the dispersion and compatibility of ZHS nanoparticles in ABS, in which polydopamine (PDA) was used as a binder to combine ZHS and MXene nanosheets. Accordingly, the prepared ABS/Ti₃C₂T_x-PDA-ZHS nanocomposites showed the enhanced properties: (1) ABS/Ti₃C₂T_x-PDA-ZHS exhibited a 69.7% increase in elongation at break compared to ABS/ZHS at a 2 mass% loading. (2) Owing to the synergistic effect of MXene and ZHS, Ti₃C₂T_x-PDA-ZHS provided excellent inhibition on heat and toxic gas release during combustion (a reduction of approximately 17.5%, 34.5%, 19.1% and 20.0% of peak heat release rate, HCN, NO and NO₂, respectively). (3) The smoke density decreased from 525.6 for neat ABS to 423.2 for ABS/Ti₃C₂T_x-PDA-ZHS with a reduction of 19.5%, and the light transmittance of ABS/Ti₃C₂T_x-PDA-ZHS (37.7%) was much higher than that of pure ABS (21.2%) at 240 s. Therefore, Ti₃C₂T_x-PDA-ZHS showed a great enhancement in flammability, toxicity and smoke release reduction of ABS, potentially overcoming the weakness with improved diversity in future applications. Graphical abstract: [Figure not available: see fulltext.]