In this work, a novel functionalization strategy for ZIF-67-modified layered MXene was proposed, aiming at improving the fire safety of thermoplastic polyurethanes (TPU). The ZIF-67@MXene was verified by microscopic morphology, elemental composition, functional group species and crystal structure, and then the successfully prepared ZIF-67@MXene was introduced into the TPU material. When ZIF-67@MXene content was only 0.5 wt%, the peak heat release rate, total heat release rate, peak smoke release rate, total smoke release rate, and CO yield of the TPU/ZIF-67@MXene composites were reduced by 26%, 9%, 50%, and 22%, respectively, compared with the pure TPU. The thermogravimetric tests showed that the residual char of TPU/ZIF-67@MXene composites was the most in all samples. In short, the high-quality carbon layer of TPU/ZIF-67@MXene composites acts as a physical barrier to the transfer of heat and toxic gases, greatly improving the flame retardant properties of the TPU polymer.

Novel hybrid flame retardants containing zinc hydroxystannate and carbon nanotubes (ZHS-CNTs) were synthesized using the coprecipitation method, and the structure and morphology of ZHS−CNTs were investigate using an X-ray powder diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and thermogravimetric analyzer (TGA). Then, the ZHS, CNTs and ZHS−CNTs were incorporated into EP, respectively, and the flame-retardant and smoke inhibition performance of the composites were compared and studied. Among the three composites, the EP/ZHS-CNT composites have the highest improvements on the fire resistance and smoke inhibition properties. With only 2.0 wt.% ZHS-CNT hybrids, the pHRR of EP/ZHS-CNT composite materials is reduced by 34.2% compared with EP. Moreover, the release of toxic gases including CO, CO₂ and SPR from the composites was also effectively inhibited. The mechanisms of flame retardant and smoke inhibition were investigated and the improved properties were generally ascribed to the synergistic flame-retardant effects between ZHS and CNTs, the catalyzing effect of ZHS and the stable network structure of CNTs.

This study is dedicated to an in−depth analysis of the combustion characteristics of extruded polystyrene (XPS) as a building insulation material with the aim of accurately assessing its fire risk in the built environment. Innovatively, this research employed a cone calorimeter equipped with a self−designed insulating sample holder to conduct a systematic experimental study. Additionally, it performed a comprehensive analysis of the ignition characteristics, heat release rate, fire hazard, smoke release, and toxic gas emission of XPS materials. The experimental results revealed that the combustion behavior of XPS is influenced by multiple factors, including the content of flame retardants and external heat flux, which significantly affect the fire hazard of XPS. When the thermal radiation intensity escalates from 25 kW/m² to 55 kW/m², the peak heat release rate of XPS−B1 rises from 428 kW/m² to 535 kW/m², marking an increase of 25.00%. Conversely, the peak heat release rate of XPS−B2 surges from 348 kW/m² to 579 kW/m², reflecting a substantial increase of 66.38%. This research not only provides a solid theoretical foundation and detailed experimental data for the fire behavior of XPS materials but also holds significant practical importance for enhancing the fire safety of buildings. Overall, this research contributes to the scientific understanding of XPS insulation materials and supports the development of more effective fire prevention measures in construction.

Cellulose-based aerogels are promising sustainable thermal-insulation materials, but their practical application is often limited by insufficient mechanical robustness and intrinsic flammability. Herein, a multiscale network-engineering strategy is proposed to fabricate a cellulose-based composite aerogel integrating structural stability, thermal insulation, and fire safety. By synergistically introducing in situ generated aluminum trihydroxide (ATH) and microencapsulated APP@ATH–MEL into the cellulose scaffold, the flame-retardant components function not only as active fire-safety agents but also as structural regulators that promote the formation of a highly interconnected hierarchical framework. This regulated architecture enhances interfacial interactions, improves load-transfer efficiency, suppresses structural collapse during freeze-drying, and introduces tortuous pathways and abundant interfaces for heat-transfer regulation. As a result, the optimized composite aerogel exhibits a low thermal conductivity of 35 mW·m⁻¹·K⁻¹ together with improved compression resistance. Thermal analysis reveals a reduced mass-loss rate and increased char yield, while cone calorimetry confirms suppressed heat release, reduced gaseous emissions, and improved residue stability. The enhanced fire safety is attributed to a synergistic multi-phase mechanism involving endothermic shielding, gas-phase dilution, condensed-phase char formation, and inorganic-residue reinforcement, which collectively inhibit heat and mass transfer during combustion. This work provides an effective strategy for the design of lightweight, mechanically robust, and fire-safe cellulose-based composite aerogels for advanced thermal-insulation applications.

Developing lightweight, eco-friendly, and fire-safe materials is essential for sustainable engineering applications. Here, we report a structurally engineered biomass aerogel constructed from a cellulose–lignin–chitosan skeletal framework reinforced with nanoencapsulated P/N–Si flame-retardant hybrids. Ammonium polyphosphate(APP) was encapsulated within a silica shell and combined with melamine (MEL) to form a multifunctional flame-retardant phase uniformly anchored onto the bio-derived network. The synergistic structural–chemical design yielded a robust, highly porous microarchitecture with enhanced hydrophobicity (water contact angle up to 73.4°), improved thermal stability (T_max increased from 195°C to 234°C), and outstanding flame retardancy (> 74% reduction in peak heat release rate), while maintaining low bulk density. Mechanistic studies reveal that during combustion, APP@SiO₂–MEL promotes phosphorylation–dehydration reactions, triggering early char nucleation and catalytic graphitization in the condensed phase. The resulting P/N-rich, SiO₂-reinforced intumescent char forms a cohesive barrier with an “indirect path” effect, significantly slowing down the transport of heat and flammable volatiles. Simultaneously, released P = O• radicals quench flame-propagating radicals in the gas phase, further suppressing combustion. This dual-phase synergistic mechanism effectively preserves structural integrity under fire exposure. This work provides a scalable, environmentally friendly strategy for producing high-performance, fire-safe biomass aerogels, offering significant potential for applications in thermal insulation, construction safety, and energy storage protection. The combination of renewable bio-based matrices and advanced flame-retardant nanotechnology represents a promising pathway toward next-generation sustainable fire-protection materials.