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Fast and effective cleanup of viscous crude oil spills remains a global challenge. Herein, by coating the melamine sponge (MS) with a bio-based flame retardant, reduced graphene oxide (rGO) and carbon nanotubes (CNTs), we prepared a flame-retardant and photo/electrothermal conversion absorbent (rGO/CNTs/FRMS) for rapid oil/water separation. The multifunctional sponge demonstrates remarkable hydrophobicity (the water contact angle: 140.0°), high oil absorption capacity (48.2–114.9 g g−1) and recyclability (89.5% after 20 cycles). Notably, rGO/CNTs/FRMS exhibits excellent thermal stability, flame retardancy and photo/electrothermal conversion performance. Under 1 sun irradiation or 9 V, the surface temperatures of rGO/CNTs/FRMS rise to 98.8 °C or 123.2 °C within 60 s, respectively. The solar-assisted and Joule-heating rGO/CNTs/FRMS drastically reduces the viscosity of silicon oil, and thus saves absorption time by 29% under 1 sun or 47% under 9 V, respectively. The proposed all-weather oil absorbent design provides a sustainable and promising solution for crude oil spill clean-up. [ABSTRACT FROM AUTHOR]

The effects of adhesive (layer) on fire performances of structural insulated panel (SIP) have been mostly ignored. This research studied modifications to the epoxy resin adhesive (EA) with expandable graphite (EG), ammonium polyphosphate (APP) and calcium carbonate (CaCO3) to prepare an intumescent flame-retardant epoxy resin adhesive (FREA) which was applied to expanded polystyrene (EPS), a typical core material of SIPs. It was found that the FREA had a char yield of 33% which was 7.6 times of that of EA and a higher viscosity than EA. The limiting oxygen index reached a maximum of 37.7% and UL94 passed the V-0 rating when the EPS was coated with FREA, of which the fire performance was even better than flame-retardant EPS. Additionally, the heat release rate, production rates of CO, CO2 and soot and sample back temperatures were all reduced compared to the EPS coated with EA. Avoiding the sample surface recession in the cone calorimeter, the custom-made spray gun system proves that the FREA can significantly increase the ignition time and lead to self-extinguishment. The degradation products of APP crosslink with CaCO3 to produce phosphates which bond with expanded EG forming the char layer to prevent heat and flame. The use of flame-retardant adhesives can lead to a sufficient fire safety level for the core material without affecting its functions. [ABSTRACT FROM AUTHOR]

Cables are the most common combustibles in nuclear power plants (NPPs) and cable fires are the one of main threaten to the safety of NPPs. Fire characteristics and fire hazards for two typical cables used in NPPs were comparatively studied based on cone calorimeter and cable tray fire tests. The heat release rate (HRR) curves show different patterns, two-peaks and three-peaks for NPP and conventional flame retardant cables, respectively. This difference is attributed to the fire barrier, which distinguishes the burning of sheath and insulation. Moreover, the maximum value of HRR for conventional flame retardant cable is much higher than NPP flame-retardant cable, and the difference is 108 kW m−2. The time from first peak to second peak for NPP flame-retardant cable is approximately four times as conventional flame retardant cable. Based on cable tray fire, the burning time after burner off is much longer for conventional flame retardant cable and its total mass loss is 0.52 kg, which are three times and five times as much as NPP flame-retardant cable, respectively, and it has a self-sustaining stage during cable burning. The above indicates that the NPP flame-retardant cable has less sustained damage, fire development rate and overall fire hazard. In addition, spacing has little effect on the burning time of sheath, but the burning of insulation layer is promoted, the time from first peak to second peak decreases with the increase in spacing. However, the influence of spacing is non-monotonous in cable tray fire, and the burning of cables with 10 mm spacing has higher fire hazard with a maximum mass loss rate. [ABSTRACT FROM AUTHOR]

Using layer‐by‐layer self‐assembly technology, an intelligent nano‐coating was constructed on melamine foam (MF) by electrostatic interactions between chitosan (CS) molecules and graphene oxide (GO) nano‐sheets. According to the principle that GO is quickly reduced to reduced GO under high temperature, a fast fire‐warning network can be constructed. Due to the protective effect of nano‐coating constructed on MF, the thermal stability and flame retardancy of melamine composite foams are improved. As the nano‐coating self‐assembly layer increases to 20, its flame‐response time is only 3 s, and the continuous alarm time is as high as 1280 s. These indicate that the prepared GO‐CS composite foam possesses excellent flame retardancy and super‐fast fire response. This study provides a novel idea for the application of bio‐based nano‐coating in the fire early response and warning. [ABSTRACT FROM AUTHOR]

Although hexagonal boron nitride (h‐BN) has presented a potential prospect in polymer composite fields, undesirable interfacial interaction with polymer matrix that generates serious aggregation of nanomaterials has suppressed its enhancement effect. Moreover, the chemically inert surface of h‐BN also makes the commonly used approach that improves the interfacial interaction between nanofillers and polymeric matrix invalid. Herein, the functionalized modification of chemically inert h‐BN was successfully fabricated by the adsorption of cetyl‐trimethylammonium bromide, with electrostatic interactions. The obtained h‐BN (cetyl‐trimethylammonium bromide‐BN) was well characterized by systematic tests and then added into thermoplastic polyurethane (TPU) matrix. The inclusion of functionalized h‐BN can dramatically improve thermal stability, flame retardant, and mechanical properties of TPU composites. With the incorporation of as low as 4.0 wt% nanofillers, maximal value of heat release rate and total heat release of TPU were reduced by 57.5% and 17.8%, compared with those of pure TPU, respectively. Moreover, tensile strength of TPU composite with a loading of 2.0 wt% was increased by 79.3% in comparison with that of neat TPU. The facile functionalized approach of chemically inert h‐BN paves the way for promising applications of h‐BN in the development of flame retardant polymer materials. [ABSTRACT FROM AUTHOR]

Composites based on poly(vinyl alcohol) (PVA) and aluminumhypophosphite(AHP) are prepared by solvent blending. The thermal, mechanical, andcrystallinity properties of the composites are studied. AHP remarkablyimproves the char residue yield during the thermal degradation andcombustion of AHP/PVA composites. The flame retardancy of the compositesis obviously improved. The increased char which protects underlyingPVA from heat and oxygen is one of the key reasons for the improvedflame retardancy. The crystallinity of the composites is decreased.The glass transition temperature (Tg)and the storage modulus of the composites are increased. In the compositewith 15 wt % AHP, limiting oxygen index (LOI) reaches 28.0%, UL-94V-0 rating is obtained, Tgis increasedby 7 °C, and the storage modulus is increased by 17.2% in comparisonwith neat PVA. Moreover, AHP/PVA composites keep high transparenceand maintain most of the mechanical properties of PVA, which is advantageousfor the practical application of the composites. [ABSTRACT FROM AUTHOR]

• Luffa sponge was applied in the gas safety protection field for the first time. • An efficient bio-based flame retardant was synthesized. • Most of the raw materials are natural renewable resources. • Flame-retardant luffa sponge has an excellent flame and explosion-proof effect. • The flame and explosion-proof mechanisms of luffa sponge were explored. Porous materials are widely employed in the gas explosion-proof field because of their abilities to dissipate shock wave energy. Luffa sponge is a biomass material with three-dimensional network structure. Thus, it will be a promising porous explosion-proof candidate material. However, luffa sponge is flammable, limiting its development in the flame and explosion-proof field. In this work, a bio-based flame retardant integrating acid catalyst, char-forming agent and foaming source was synthesized. Then the flame-retardant luffa sponge is prepared through impregnation method, and it is employed to the gas explosion-proof field for the first time. The flame-retardant luffa sponge can completely prevent the explosive flame spread, and its explosion overpressure decay ratio can reach up to 84%. The flame-retardant luffa sponge has superior flame and explosion-proof performances, and it can be produced on a large scale. This work provides a novel idea for the research and development of efficient flame and explosion-proof materials by the utilization of renewable resources. [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional smart textile was fabricated by a simple impregnation method. • Excellent flame retardancy, electrical conductivity and hydrophobicity were acquired. • Self-powered triggered fire-alarm system was designed and engineered. The domain of smart textiles represents a widely researched area, showcasing promising prospects. Herein, a multifunctional smart textile (CF@PM-AA) has been designed and fabricated, amalgamating flame retardancy, electrical conductivity, and hydrophobicity into a unified entity. The flame retardant, synthesized through the reaction between amino trimethylene phosphonic acid and allantoin, was impregnated into cotton fabric through a facile impregnation method. Through surface modification with polydimethylsiloxane and multi-walled carbon nanotubes, the obtained CF@PM-AA acquires exceptional hydrophobic and acid-base environment durability. Significantly, the electrical conductivity of CF@PM-AA is greatly enhanced, with a reduced resistance down from 15.9 GΩ to 13 MΩ. Based on their electrical characteristics, the copper sheet and CF@PM-AA function as the electrode and friction layers, respectively, in the construction of the triboelectric nanogenerator. This configuration produces a voltage output of up to 125.6 V at a frequency of 4 Hz. Given its outstanding flame retardancy, hydrophobicity, and electrical performance, CF@PM-AA can be integrated into firefighting suits to establish a fire-alarm system with remote signal transmission function, enhancing personnel safety. Simultaneously, the CF@PM-AA holds promise for diverse applications in wearable flame-retardant and fire-alarm systems, opening new avenues for smart textile utilization in the Internet of Things domain. [ABSTRACT FROM AUTHOR]

Early fire warning holds immense potential for achieving more efficient fire-safety management. Despite the emergence of numerous fire-alarm sensors in recent years, they display deficiencies in providing prompt and repeatable early detection during fire accidents, thus failing to mitigate potential losses. Herein, we demonstrated a bio-based fire-warning film with chitosan (CS) and amino trimethylene phosphonic acid (ATMP) prepared by an environmental-friendly water evaporation method. The transparency, thermal stability, flame retardancy and fire-warning performances of CS and CS-ATMP films were comprehensively investigated. Remarkably, the inclusion of ATMP results in a significant improvement in the thermal stability and char yield. Moreover, the total heat release value of CS-ATMP-1 film exhibits a remarkable 35.7% reduction compared to that of pure CS film, demonstrating a substantial enhancement in flame retardancy. The thermosensitive properties of CS endow it with fire-warning capabilities. The CS-ATMP-2 film triggers an alarm signal within 0.3 s and the signal maintains for 196.0 s under alcohol flame attack, indicating its high sensitivity and stable alarm signal. Furthermore, the possible flame-retardant and fire-alarm mechanisms are proposed. This bio-based CS-ATMP film with excellent flame-retardant and repeatable early warning capacities manifests promising applications in building fire prevention and detection. [Display omitted] • Transparent bio-based CS-ATMP films were prepared by water evaporation method. • Fire-retardant and fire early-warning performances of films were investigated. • Fire-retardant and proton conductivity mechanisms were explored. [ABSTRACT FROM AUTHOR]

Developing thermoplastic polyurethane (TPU) composites with excellent fire-safe properties is greatly significant to expand the application fields. Two-dimensional MXene has been proven effective in reducing fire hazards of TPU whereas its poor dispersion in TPU is a serious concern. Herein, benzyl trimethyl ammonium chloride and victoria blue B modified Ti 3 C 2 were synthesized through interface engineering methods and TPU composites were prepared via severally introducing the two modified Ti 3 C 2 by solvent mixing and hot pressing measures. No apparent agglomeration is observed, suggesting uniform dispersion of functionalized Ti 3 C 2 in TPU. The TPU composites present superior performances in flame retardancy and smoke suppression, and the distinguished fire safety can be attributed to the physical barrier and catalytic charring effect of functionalized Ti 3 C 2 and TiO 2. This research presents a convenient way to obtain functionalized Ti 3 C 2 , enriching the future applications of MXene as flame retardant and reducing the fire hazards of TPU. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Lean-fuel, stoichiometric and rich-fuel mixtures combustion were investigated. • Flame quenching occurred when the equivalence ratio was 0.5. • Copper foam promoted the explosion when the equivalence ratio was 1.5. • Mechanism of flame retardant and explosion suppression of copper foam was verified. This study investigates the effect of copper foam sheets on explosion suppression in hydrogen/air mixtures with different equivalence ratios (φ). The explosion experiment is conducted in a circular tube with a large aspect ratio (1 0 8). The phenomenon of flame quenching can be observed distinctly in the case of φ = 0.5. In the case of φ = 1.5, the copper foam sheets are destroyed by the reflected shock wave, and the overpressure rises by 65 %. In addition, a longer duration of peak overpressure and a lower attenuation rate can be observed due to the interaction between the shock wave and flame front. For the cases of φ = 1.0 and 2.0, the copper foam sheet effectively prevents flames and shock waves from reflecting. The experimental results provide an essential reference for the design of hydrogen flame arresters, the safety of hydrogen pipeline transportation, and engineering application. [ABSTRACT FROM AUTHOR]

The eco-friendly and simple layer-by-layer (LbL) self-assembly process is used to create a graphene oxide (GO) and aluminum oxide hydroxide (AlOOH) functional coating on melamine foam (MF) by utilizing the hydrogen bonding interaction. The manufactured composite foam exhibits good hydrophobicity and structural stability in the both strong acidic and alkaline solutions. The AlOOH-GO composite coating's electrical resistance is susceptible to flame and high temperature, allowing for ultra-fast fire detection and efficient fire-warning response. When the composite foam is attacked by flame, it triggers an alarm signal within 2.5 s and a continuous alarm time access of 256 s, demonstrating exceptional early fire-warning capability. The thermal stability of this combustible foam is improved by the optimized AlOOH-GO composite coating. The AlOOH-GO composite coating endows MF with exceptional flame-retardant properties, including self-extinguishing and structural integrity after combustion. This work proposes an efficient method for considerably reducing the fire hazard of flammable materials and expanding the applications in a fire early detection and warning. [Display omitted] • A novel early fire-alarm sensor was designed based on AlOOH-GO nano-coating. • The sensitivity and stability of this novel fire sensor were excellent. • The fire-alarm and flame-retardant mechanisms of AlOOH-GO nano-coating were studied. [ABSTRACT FROM AUTHOR]

A novel hyperbranched charring foaming agent (HCFA), successfully prepared via an A 2 B 3 approach with about 97% yield, was combined with ammonium polyphosphate (APP) to flame-retard polypropylene (PP) at a 30 wt% loading. The results of thermogravimetric analyses of various PP samples in air and nitrogen showed that the HCFA/APP system could effectively improve the thermal and thermal-oxidative stabilities of the char residues. And PP3 with a 3/1 mass ratio of APP to HCFA left the highest amount of char residue at 800 °C. The studies of their flammability revealed that the addition of HCFA can make great contribution to the increase of the limiting oxygen index and the UL-94 V0 rating, and the decrease of the heat release rate (HRR) and fire growth index (FGI) of PP/APP/HCFA composites relative to PP with 30 wt% APP. The investigation of their water resistance demonstrated that the PP composites with a mass ratio of APP to HCFA being between 3:1 and 1:1 still obtained a UL-94 V-0 rating after 168 h soaking in hot water, due to the delayed migration of intumescent flame retardant from the complexation between hydrophilic APP and hydrophobic HCFA. Besides, their mechanical properties were also investigated. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol/cellulose nanofibers hybrid aerogel was prepared under freeze drying method. To improve the aerogels' anti-combustion performance, 0.8 wt% microencapsulated ammonium polyphosphate (MCAPP) was loaded as the flame retardant. Aerogels with extremely low density (~0.06 g/cm3) and excellent mechanical performance (Young's modulus: 1.045 MPa) can be obtained. The resulted aerogel also exhibit considerable thermal insulation ability (thermal conductivity: ~0.04 W/m·K). Experimental results indicate that the value of limiting oxygen index increases from 19.5% to 37.5% when loading 0.8 wt% MCAPP. Accordingly, the aerogels' peak heat release rate decreased significantly from 222.44 to 107.84 kW/m2. The char residue rises when introducing MCAPP and the char's integrity improves a lot after combustion. The fire performance index and fire growth index increases and falls respectively, indicating improved anti-combustion performance. X-ray photoelectron spectroscopy results show C O bonds would be increased for the esterification of phosphoric acid from MCAPP. In addition, the production of carbonate can be prohibited while combustion when loading MCAPP. • Monolithic PVA/CNF/APP hybrid aerogels are obtained by freeze drying. • Aerogel flammability decreases significantly while loading 0.8 wt% APP. • Tripling aerogel's Young's modulus has been achieved by just loading 0.8 wt% APP. [ABSTRACT FROM AUTHOR]