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• A multifunctional smart textile has been designed and fabricated. • Excellent flame retardancy, electrical conductivity and hydrophobicity were acquired. • Self-powered triggered fire-alarm systems were engineered. In the realm of smart textiles, an area garnering significant research attention and demonstrating vast developmental potential, we have conceived and fabricated a multifunctional smart textile with a fire dual-warning function. This innovation integrates thermoelectric performance, triboelectric nanogenerator (TENG), flame retardancy, and hydrophobic functionalities into a cohesive entity. Employing a straightforward impregnation method, we successfully infused cotton fabric (CF) with a novel flame retardant (named AA). Additionally, CF/PPA is modified by incorporating poly(3,4-ethylene dioxythiophene)-poly(styrene sulfonate) (PEDOT:PSS) and polydimethylsiloxane (PDMS) as separate layers, with the former providing thermoelectric properties and the latter enabling TENG functionality in smart textiles. This configuration exhibits excellent voltage output performance, generating a thermoelectric effect of 221 mV under a temperature differential of 76 K and achieving voltage output as high as 138 V at a vertical contact-separation frequency of 5 Hz. The superior dual-warning function, flame-retardant properties, and hydrophobicity of CF/PPA can be integrated into firefighting apparel, thereby establishing fire-alarm systems with remote signal transmission capabilities to enhance personnel safety. Furthermore, CF/PPA holds promising dual warning application prospects in the field of wearable flame-retardant and fire-alarm systems, thus paving new avenues for the utilization of smart textiles in the realm of the Internet of Things (IoT). [ABSTRACT FROM AUTHOR]

[Display omitted] • A multifunctional ceramifiable silicone foam was fabricated with MWCNT and MXene. • The foam showed outstanding flame retardancy and ceramization performance. • The foam could trigger the fire-alarm system within 3 s when being burned. • The foam displayed excellent repeat fire-warning capability and thermal stability. • The foam exhibited good mechanical and piezoresistive sensing performance. The development of multifunctional silicone foam with high fire safety is of great significance to realize intelligent fire protection but challenging. Herein, a multifunctional ceramifiable fire-retardant silicone foam (MCSF) was fabricated by Ti 3 C 2 T x nanosheet (MXene), multiwalled carbon nanotube (MWCNT), γ-aminopropyltriethoxysilane (APTES), Karstedt catalyst (Pt) and vinyl dimethylsiloxane via water–oil interface induced self-assembly and dehydrogenation foaming at room temperature. MCSF possessed low density and good mechanical properties. Its improved thermoelectric performance and sensitive fire-warning capability of MCSF were attributed to the skeleton supporting effect and unique electron transport effect between MWCNT and MXene. When being burned, MCSF was able to trigger the fire-warning system within 2.4 s and repeatedly alarm the fire reignition. Furthermore, owing to the synergism between APTES and Pt, MCSF exhibited good ceramization performance. When encountered high temperature, the MCSF surface rapidly ceramized, generating a ceramic-like barrier layer to block the further flame ablation, and it quickly self-extinguished after removing from flame. Besides, MCSF showed impressive thermal insulation and durable piezoresistive sensing. This work provides a new strategy for the preparation and application of multifunctional fireproof polymer foams. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bio-based phosphorylated P-FMa was prepared by self-stabilized precipitation polymerization. • P-FMa has regular morphology, uniform particle size and excellent flame retardant effectiveness. • P-FMa effectively reduced the smoke production and heat release rate by 52.6 % and 41.8 %. • Impact strength of the PP/APP/P-FMa increase by 138.6 % compared to PP/APP. Preparation of polyolefins possessing superior flame retardant and mechanical properties has always been a hot research topic. Herein, a novel high-performance flame retardant was designed and prepared to address the dilemma between flame retardancy and mechanical properties. Through self-stabilized precipitation polymerization of furfuryl alcohol (FA) and maleic anhydride (Ma), followed by successive amination and phosphorylation treatment, bio-based phosphorylated FMa microspheres (P-FMa) were successfully obtained. Benefiting from strong synergistic effect between P-FMa and ammonium polyphosphate (APP), the polypropylene (PP)/APP/P-FMa composites exhibited excellent flame retardant and smoke suppression properties. At a dosage of only 19 wt% APP/P-FMa, the PP/APP/P-FMa reached UL-94 V-0 rating and a limiting oxygen index of 32.2 %, and the peak heat release rate and peak smoke production rate decreased by 76.1 % and 52.6 % compared with neat PP, respectively, due to the formation of denser and firmer char layer. Notably, the tensile strength of PP/APP/P-FMa maintained at a high level of 43.2 MPa. More importantly, the impact strength reached 10.5 kJ/m2, increase by 138.6 % compared to PP/APP, mainly attributed to improved dispersion and compatibility between APP/P-FMa and PP matrix. Owing to its ability to simultaneously improve flame retardant and mechanical properties, P-FMa possesses great potiential as a high-performance flame-retardant filler. [ABSTRACT FROM AUTHOR]

[Display omitted] • The construction of porous d-LDH@ZIF heterostructures with abundant defects and vacancies through in situ growth and defect engineering strategies. • First report of porous liquid in flame retardant field. • A flame retardant-functionalized porous liquid (PLs-d-L@Z) was designed to improve the fire safety and mechanical properties of polyurea composites. • An inspiration for the design of liquefied functional fillers and the influence on the comprehensive properties of composites. Preventing aggregation and inducing homogeneous dispersion of flame retardant nanofillers is critical to enhance the fire safety and mechanical properties of nanocomposites. Although chemical modifications are commonly used to improve the filler's compatibility with the polymer chain, such methods are often cumbersome and limited. Herein, porous liquids (PLs) with flame retardant function were constructed in which porous defect-Co-LDH@ZIF-67 (d-LDH@ZIF) heterostructure particles were converted into liquid materials by electrostatic interaction with a large-volume solvent. This is also the first report of PLs in the field of flame retardant. Specifically, the d-LDH@ZIF heterostructure was designed by defect engineering and in situ growth strategy to compensate for the low catalytic activity and specific surface area of Co-LDH, and to serve as a rigid porous framework for PLs. Numerous cobalt/oxygen vacancies and lattice defects in the d-LDH@ZIF heterostructure have also been proven to confer higher flame retardancy relative to Co-LDH. d-LDH@ZIF porous liquids (PLs-d-L@Z) presents favorable liquid characteristics and achieves a monodisperse state in the polyurea matrix. The limiting oxygen index of polyurea composites blended with 20 wt% PLs-d-L@Z (3 wt% d-LDH@ZIF content) can be increased to 24.2 % and pass the V-0 rating in the UL-94 test. Moreover, the peak of heat release rate, total heat release, and total smoke production are reduced by around 40.4, 27.0, and 39.9 %, respectively, compared to neat polyurea. Emphatically, the PLs-modified polyurea composites exhibit significantly improved mechanical and impact resistance properties, as well as favorable chemical resistance. This strategy of liquefying solid flame retardant fillers will open an avenue to the design of functional nanomaterials for fire safety and other potential applications. [ABSTRACT FROM AUTHOR]

• Detailed a methodology to develop a pyrolysis reaction model for EP/IFR (Epoxy blended with intumescent flame retardants). • Identified and quantified the interaction between epoxy matrix and IFR. • Captured the TGA/DSC/MCC data of EP/IFR as a function of material composition. • Revealed the impact of IFR on char forming and pyrolyzates production. • Enabled the intelligent design of EP/IFR with enhanced flame resistance. This paper presents a methodology to develop a pyrolysis reaction model that captures the flammability behavior of epoxy-based intumescent flame retardant coatings (EP/IFR) as a function of material composition. This approach adopted Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Microscale Combustion Calorimetry (MCC) experiments as well as the inverse modeling of the experimental results using ThermaKin2Ds and COMSOL Multiphysics modeling framework. The interactive reactions between EP and IFR were identified and quantified in the resulting lumped model, which is based on fitting of experimental data. It was found that the developed model was able to reproduce the TGA/DSC/MCC data within the prescribed criteria for EP/IFR blends with different material compositions. The model's extrapolating capability was further validated through accurately predicting the experimental TGA data under different thermal conditions and for blends with different IFR ratios which were not used for model development. Additional TG-FTIR and XPS experiments were conducted to quantify the effect of IFR additive on the evolution of gaseous products and char formation. With a higher ratio of IFR, the amount of fuel dilution gases (i.e., CO2, NH3) was increased and the amount of combustible organic gaseous products was reduced. This work provides the core subset parameters for comprehensive pyrolysis modeling and enables the intelligent design of EP/IFR coatings with enhanced flame resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sucrose-furan-glyoxal (SFG) foam was synthesized with azodicarbonamide (AC) as foaming agent. • Ammonium dihydrogen phosphate (ADP) was added to enhance flame retardancy. • The foam has lower pulverization ratio and outstanding compressive strength. • The foam's closed cell structure gives it a low thermal conductivity. • The foam is biodegradable. As sucrose is less expensive and more readily available than tannin, sucrose-based foams were prepared by incorporating furfuryl alcohol (FA) and glyoxal as a crosslinking agent to obtain sucrose-furan-glyoxal (SFG) resin. Ammonium dihydrogen phosphate (ADP) was then incorporated into SFG and foamed with azodicarbonamide (AC) to form SFGA foam. The study examined the chemical structures, morphology, mechanical properties, thermal properties and flame retardancy of the foams. The findings indicated that the SFGA foam exhibited a closed cell structure characterized by a smooth surface as well as high compressive strength and shore hardness. The closed structure of SFGA provides the foam with good thermal stability and excellent flame retardancy, as demonstrated by its limiting oxygen index (LOI) of 43.3 %. The combustion test demonstrated that the SFGA foam attained the UL-94 V-0 flame retardant classification. During the process of combustion, the primary volatile compounds identified were carbon dioxide, acetic acid, and oxanes. No toxic substances such as alkanes were detected. In addition to its outstanding flame retardant properties, SFGA foam is also capable of biodegradation. After being buried in soil for 30 days, it exhibited a weight reduction of 2.7 %. The SFGA foam underwent a weight reduction of 0.69 % in the laboratory when exposed to Penicillium sp for a duration of 20 days. The study proposed that sucrose can serve as a substitute for tannin in the production of rigid foam, which is suitable for insulation materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ammonium polyphosphate was grafted onto lignin to form Lig-APP through the in-situ solid-phase polycondensation. • Only 3 wt% Lig-APP can endow PLA with the UL-94 V-0 rating and LOI of 27.6 %. • The tensile strength, Young's modulus and the impact strength of PLA/3Lig-APP increased by 3.7%, 10.6% and 17.3%. • Lig-APP can endow PLA with excellent UV resistance property. Polylactic acid (PLA) exhibits intrinsic high flammability, inadequate toughness and UV resistance, which impedes its adoption into novel industry sectors. Although lignin-based fire retardants have shown high efficiency in PLA, their poor interfacial compatibility with PLA deteriorates mechanical properties and the preparation often involves use of plethora of organic solvents. Herein, a sustainable in situ solid-phase polycondensation strategy has been used to prepare a lignin-based fire retardant, Lig-APP, by grafting ammonium polyphosphate onto lignin without using any organic solvent. As-synthesized Lig-APP has shown an increased charring ability and excellent fire retardancy in PLA. With only 3 wt% loading of Lig-APP, PLA achieved a UL94 V-0 rating and a limiting oxygen index (LOI) of 27.6 %. Moreover, Lig-APP simultaneously strengthened and toughened PLA while increasing the UV resistance of PLA. This work opens an innovative eco-benign avenue to create biobased fire retardants and high-performance PLA biocomposites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Squid ink (SI) can be obtained from waste ink glands. • Squid ink is rich in proteoglycan, melanin, and metal ions. • The treated silk exhibit superior flame retardancy, good UV protection and washing durability. • The proposed approach offers a sustainable and cleaner method for creating high value-added silk. Today, marine biomolecules have attracted great interest in the field of flame-retardant (FR) science due to their sustainability and charring properties. Squid ink is mixed bio-colloid rich in proteoglycans, melanin, and metal ions. Here, squid ink was applied to endow silk with outstanding FR performance and ultraviolet protection through surface coating. After coating with 40 g/L squid ink, silk displayed excellent ultraviolet shielding performance with a high UV protection factor (UPF) of 71.5, attributing to powerful ultraviolet absorption ability of melanin. Besides, the coated silk also exhibited outstanding FR performance, characterized by a shorter char length (7.1 cm) and a higher FR-Index (2.5). The heat release performance of the treated silk dramatically decreased, and the peak heat release rate (pHRR) and heat release capability (HRC) both decreased by 49.1 %. Moreover, a significant reduction in total smoke production (TSP ∼ 60 %) was also observed in cone calorimetry test. A reduction in these fire parameters indicated a great improvement in the fire safety of silk. Interestingly, due to the natural adhesiveness of the proteoglycan mixed colloid, the coated silk could withstand 10 washing cycles while maintaining FR properties. Subsequently, further analyses of the cone residues confirmed the formation of a compact and stable char layer. The squid ink coating exerted an intumescent FR action on silk. [ABSTRACT FROM AUTHOR]

[Display omitted] • A micro-protective coating was applied to the multi-scale microstructure of wood. • The porous structure of wood is preserved, maintaining its permeability. • Multi-scale micro-coatings provide wood with excellent fire safety properties. • Wood gains antibacterial, photoaging-resistant, and corrosion-resistant properties. • This strategy has been proven reliable, versatile, and durable for various metals. Wood, a naturally renewable material with a porous structure and breathability, rendering it a green construction material that can absorb sound, isolate heat and regulate moisture. Efforts to enhance wood's resistance to combustion while maintaining its porous nature are hindered by the potential impact of physical and chemical treatments on its porous structure, posing a challenge in achieving flame-retardant wood that retains its breathability. Inspired by the multi-layer coating decoration method used on walls of various rooms in frame structure buildings, the study applies multi-scale micro-coating strategy to the multi-scale microstructure of wood. This strategy applied polyamino polyether methylene phosphonate (PAP), metal ions (Al3+/ Mg2+/ Ca2+), and alkali solutions to create a persistent multifunctional protective coating for the multi-scale wood structure. This coating effectively preserved the wood's vessel, ray tissue, cell cavity, and pit structure, protecting its permeability. The modified wood demonstrated an increased limited oxygen value from 19.7 % to 38.4 % and a 55.9 % decrease in the total smoke release compared to natural wood, obtaining high fire safety. Furthermore, the modified wood exhibited adjustable antibacterial, photoaging-resistant and corrosion resistance properties depends on the type of metal. This strategy demonstrated proven reliability, versatility, and durability in the treatment of various metal ions, enabling the production of functional wood with tailored properties. [ABSTRACT FROM AUTHOR]

Construction of phosphorus-containing polyimine vitrimer film by incorporating ionic liquid BMIM∙PF 6 for enhanced mechanical, flame-retardant and reprocessable properties. [Display omitted] • A composited polyimine vitrimer films (Ionic-PIs) were synthesized by using ionic liquid BMIM∙PF 6 containing flame retardant elements N, P and F as the regulator. • The mechnical properties of Ionic-PIs were improved through the hydrogen bonding interactions and microphase separation mechnism. • The prepared Ionic-PIs exhibited enhanced flame retardancy and excellent reprocessability as well as degradable recyclability. • This work is helpful to provide a simple and feasible strategy to modulate the comprehensive properties of cross-linked polyimine vitrimer. A composited flame-retardant phosphorus-containing polyimine vitrimer films (Ionic-PIs) were synthesized by using ionic liquid BMIM∙PF 6 containing flame retardant elements N, P and F as the regulator. The effects of the addition amount of BMIM∙PF 6 on the mechanical properties, degradation, recycling, and flame retardancy were investigated. Compared to intrinsically phosphorus-containing polyimine film (PI), the composited Ionic-PIs exhibited better mechanical strength and toughness. Hydrogen bonding interactions between BMIM∙PF 6 and polyimine network greatly increased Ionic-PI's mechanical strength at a low addition of 1 wt%, and the microphase separation caused by the aggregation of BMIM∙PF 6 drastically enhanced their toughness as the addition increased. Ionic-PIs exhibited excellent reprocessability at 85 °C and degradable recyclability under acidic conditions. In addition, due to the synergistic effect of condensed-phase and gas-phase flame-retardant mechanisms, the Ionic-PIs possessed good flame retardancy with LOI above 27 % and a UL-94 test reaching VTM-0 grade, which was important for the high-fire safety of polyimine vitrimer. This work is helpful to provide a simple and feasible strategy to modulate the comprehensive properties of cross-linked polyimine vitrimer film and to expand their applications in many fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel macromolecular hybrid was synthesized. • Excellent flame retardancy and smoke suppression were enabled via hybrid method. • Compatibility between three thermally conductive fillers and Al-IFR was studied. • A delicate balance between fire safety and thermal conductivity was achieved. Achieving a delicate balance between fire resistance and thermal conductivity in intumescent flame-retarded polypropylene (PP) poses a formidable challenge, primarily due to the susceptibility of intumescent barrier layers to functional fillers. To address this concern, a novel hybrid macromolecule (Al-PAP) was synthesized via polycondensation reaction, showcasing promising potential in constructing flame-retardant and thermally conductive PP. Remarkably, the inclusion of mere 14 wt% of the Al-PAP/melamine polyphosphate (Al-IFR) system raised the limiting oxygen index (LOI) of PP to 28.3 %, equivalent to that of PP containing 20 wt% of the conventional system, emphasizing the superior efficacy of the hybrid Al-PAP. Further, the PP with 20 wt% Al-IFR performed a 32.2 % of LOI, 850 °C of glow wire ignition temperature, >960 °C of glow wire flammable index and UL 94 V-0 ratings (3.2 mm & 1.6 mm), indicating the high flame retardancy. Subsequently, three thermal conductive fillers – aluminum oxide, boron nitride, and multi-walled carbon nanotubes – were evaluated based on a 20 wt% dosage of Al-IFR. Alumina emerged as the optimal candidate, enhancing flame retardancy and smoke suppression while imparting thermal conductivity to PP. Conversely, the other two fillers compromised fire-safety performance. Notably, the composite 5Al 2 O 3 /20Al-IFR/PP exhibited a 90.8 % lower peak heat release rate and an 88.2 % lower peak smoke production rate compared to PP. Additionally, its thermal diffusivity and thermal conductivity were 27.0 % and 48.9 % higher than those of PP, respectively. In short, this work combined molecular design and comprehensive screening to build the thermally conductive PP with high flame retardant efficiency, and relevant mechanisms were also investigated. [ABSTRACT FROM AUTHOR]

• A self-assembly coating with two bilayers to improve fire safety of expandable polystyrene (EPS). • Covalent connections between surface coating and activated EPS induced by ultraviolet-ozone. • The good flame retardant durability of the surface coating constructed by the ultraviolet curing. • A novel amino-intercalated kaolinite for enhancing the flame retardancy and smoke suppression. Layer by layer (LBL) self-assembly coatings upon expandable polystyrene (EPS) surface play an important role in improving its flame retardancy. However, a large number of layers is needed to achieve a satisfied fire performance, and the coatings are difficult to adhere on the inert EPS surface, resulting in the poor durability. In this work, the surface of EPS was activated by ultraviolet ozone (UVO) with the appearance of oxygen contained groups, then a LBL coating with only two bilayers (branched polyethyleneimine (BPEI)-kaolinite (kaol)-BPEI-diethylene triamine penta (methylene phosphonic acid)) was covalently connected on the EPS surface. Compared with neat EPS, the obtained E-K 5 D 30 sample increased the value of limiting oxygen index (LOI) from 18.8 % to 37.7 %, improved the ignition time from 59 s to 95 s, reduced the peak heat release rate (pHRR) value from 282.0 kW/m2 to 220.9 kW/m2, and enhanced the char residues from 6.3 % to 32.3 % after the combustion. Moreover, an ultraviolet (UV) curing layer with P/N elements was prepared upon E-K 5 D 30 sample to maximize the flame retardant durability. A novel amino-intercalated kaol was used to play a smoke suppression role. The results showed that E-K* 5 D 30 -P 8 N 3 sample further increased the LOI to 39.2 %. Even after 12 h washing, the E-K* 5 D 30 -P 8 N 3 sample exhibited a slight LOI reduction to 37.8 %, and fire performance index (FPI) value of 0.405 m2·s/kW, showing the successful construction of coatings with good fire safety and flame retardant durability. [ABSTRACT FROM AUTHOR]

• A novel Zeolite@DPA-Cu flame retardant was designed and prepared by a simple and environmentally friendly method. • Zeolite@DPA-Cu improves the fire safety and smoke suppression of EP. • The Zeolite@DPA-Cu endows EP with excellent mechanical properties. The preparation process of new environmentally friendly flame retardants to endow epoxy resin (EP) with excellent flame retardancy and mechanical properties remains a challenging task. In this study, a novel Zeolite@DPA-Cu flame retardant was designed and prepared by a simple and environmentally friendly aqueous preparation process using zeolite, copper sulfate and diphenylphosphonic acid as main raw materials. As expected, Zeolite@DPA-Cu significantly improved the flame retardancy and mechanical properties of EP composites. The results showed that the LOI and UL-94 grade of the EP/5 wt% Zeolite@DPA-Cu composite reached 32.4 % and V-0 rating, respectively. The synergistic effect of the physical barrier, free radical capture and catalytic char formation of Zeolite@DPA-Cu significantly improved the flame retardancy of EP. In addition, due to the strong interfacial interaction between Zeolite@DPA-Cu and EP, the tensile strength and elongation at break of the EP were increased to 57.92 MPa and 4.7 %, respectively. Generally, this study proposed a modification strategy that takes into account both flame retardancy and mechanical properties, which is extremely important for the practical application of EP flame retardant materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel water-soluble lignin-based N-P flame retardant was synthesized. • Modified wood showed good mechanical properties and dimensional stability. • Modified wood achieved a reduction of 56.8% in THR and 92.3% decrease in TSP. • The flame-retardant mechanism of modified wood has been revealed. The development of effective and eco-friendly wood-based functional composites is crucial for maximizing the value of forest resources. In this paper, we propose a novel method for preparing an aqueous-phase flame retardant (MPUC) using carboxymethylation alkali lignin, phytic acid, and melamine-urea-glyoxal resin. This approach aims to manufacture modified wood (MW/MPUC) with exceptional flame-retardant and smoke-suppressing properties. The results from the cone calorimeter test indicate that the modified wood achieved a remarkable reduction of up to 56.8 % in total heat release and an impressive 92.3 % decrease in total smoke production. Furthermore, the limiting oxygen index increased significantly from 23.6 % (natural wood) to 41.5 % (MW/MPUC-2). Notably, all modified wood successfully passed the V-1 test for UL-94 flammability rating. Further, our investigation into the gas-phase products formed during pyrolysis and the condensed-phase system created after combustion has led us to propose potential flame-retardant mechanisms for these flame retardants. Moreover, modified wood had improved mechanical properties and dimensional stability than natural wood. In addition, we extended the application of MPUC-2 flame-retardant to other flammable materials and demonstrated its excellent flame-retardant properties. Thus, the proposed strategy provided a new approach for preparing wood-based flame-retardant composites with lignin-based N-P flame retardants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermal-curing phosphorus-containing flame retardant HPG coating was prepared. • HPG coating endowed RPUF excellent flame retardancy and fire hazardous safety. • The crosslinked HPG coating provided RPUF enhanced compressive property. • HPG coated on RPUF had good heat insulation and water resistance. • The flame–retardant HPG/RPUF is promising as heat–insulation material. A phosphorous-containing HEMAP–co–GMA (HPG) prepolymer was successfully prepared by the ring-opening reaction of glycidyl methacrylate (GMA) and 2–hydroxyethyl methacrylate phosphate (HEMAP) as monomers, and flame retardant HEMAP–GMA copolymer (HPG) coating on the surface of rigid polyurethane foam (RPUF) was further fabricated by free-radical thermal-curing. The HPG coating endowed RPUF excellent flame retardancy and fire hazardous safety. The HPG coated on RPUF (HPG/RPUF) reached UL94 V–0 rating, and the limited oxygen index value of the HPG-2/RPUF improved from 19.0 % of RPUF to 27.8 %. The cone calorimetric test results showed that the total heat release and mean peak heat release rate values of the HPG-2/RPUF reduced by 79.6 % and 54.6 % compared to those of RPUF, respectively. The flame–retardant mechanism of HPG/RPUG was speculated the synergistic flame retardant effect between the barrier of the dense char layer and the inhibition of phosphorus–containing free–radicals. The three–dimensional crosslinked HPG coating not only provided HPG/RPUF excellent water resistance, but also enhanced compressive properties and heat–insulation. The highly efficient flame–retardant HPG coating has great potential in fire protection of the heat insulation foams. [ABSTRACT FROM AUTHOR]

[Display omitted] • Imidazole-based liquid compounds containing different P oxidation states were synthesized for curing EP. • EP-DCPPI and EP-PPOAI show the combined flame-retardant mechanism of gas-phase and condensed-phase flame retardancy. • EP-DCPPI and EP-PPOAI show excellent flame-retardant, mechanical properties and heat resistance. In this work, two phosphorus-containing liquid imidazole compounds with different phosphorus oxidation states (1,1′-(phenylphosphanediyl)bis(1 H -imidazole) (DCPPI) with + 1 valence phosphorus, and imidazole-phenylphosphate (PPOAI) with + 3 valence phosphorus) were designed and synthesized. Both of DCPPI and PPOAI were used as curing agents to obtain intrinsic flame-retardant epoxy resin (EP-DCPPI and EP-PPOAI), in which the imidazole group was used as the curing group of EP, and the phosphorus-containing group was directly connected to the EP crosslinking network. On the one hand, the efficient flame-retardant groups containing + 1 or + 3 valence phosphorus were incorporated into the EP system to obtain excellent flame-retardant properties; on the other hand, the introduction of phenylphosphine or phenoxyphosphine groups in the molecular chain of EP greatly enhanced the interaction between molecular chains, adjusted crosslinking density and endowed EP with excellent tensile strength and toughness. Compared with imidazole cured EP (EP-MZ), the peak heat release rate (PHRR) of EP-15DCPPI and EP-15PPOAI decreased by 70 % and 68 %, and the total heat release rate (THR) decreased by 37 % and 36 %, respectively. Meanwhile, EP-15DCPPI passed UL-94 V-0 rating, and the limiting oxygen index (LOI) reached 36.1 %. EP-15PPOAI passed UL-94 V-1 rating and the LOI reached 29.1 %. The flame-retardant mechanism was analyzed and discussed. Compared with EP-MZ, the dynamic and static mechanical properties of EP-15DCPPI and EP-15PPOAI were enhanced simultaneously, and the glass transition temperature (T g) was obviously increased. [ABSTRACT FROM AUTHOR]

A novel flame-retardant gel polymer electrolyte (GPE) with a three-dimensional interconnected network is prepared by means of structural modification. Credited to the synergistic flame retardancy of P-Si and the speedy conduction of Li+ ions, the GPE possesses superior safety and excellent electrochemical performance, fully catering to the demands for high stable and energy density in power batteries. [Display omitted] • A nonflammable GPE is synthesized by in-situ copolymerization on cathode electrode. • The star-shape interpenetration network bestowed on GPE a rapid Li+ conductivity. • A P-Si synergic flame retardancy imparts a safety reliability for battery system. • The advantages and mechanisms of Li+ transport are elucidated by MD calculation. Concurrently attaining elevated safety and electrochemical performance in the realm of high-energy–density batteries represents a considerable challenge. Drawing inspiration from the synergistic flame-retardant concept of the P-Si element, a reactive phosphorus-containing flame retardant was meticulously devised that in conjunction with a nano octa-arm crosslinker featuring Si-O-Si and vinyl groups, collectively establishing a star-shaped crosslinked framework to resolve the issue of matrix compatibility and achieving the polymer matrix with intrinsic flame retardancy. Hence, a non-flammable composite gel polymer electrolyte (GPE) was fabricated. The composite GPE-based batteries, encompassing LiFePO 4 ||Li, NCM523||Li and LiFePO 4 ||Graphite, all exhibit commendable cyclic stability under 1C. Furthermore, deriving from the collaborative flame retardant characteristic, pouch cells incorporating the composite GPE displayed remarkable non-flammability and safety characteristics in various tests such as nail penetration, mechanical abuse and ignition scenarios, showcasing a notable 63.3 % reduction in maximum surface temperature. Intriguingly, the insights arising from Molecular Dynamics (MD) simulations indicate the migration mechanism for Li+ within a three-dimensional interpenetrating network, hence unmasking that feasible intra-chain hops of Li+ play a pivotal role. [ABSTRACT FROM AUTHOR]

[Display omitted] • A P/N/Si-containing hyperbranched polymer Si-DP was synthesized as a multifunctional modifier for one-component epoxy resins. • Si-DP provides simultaneous improvement of toughness, strength, flame retardancy, smoke suppression and dielectric properties of one-component epoxy resins. • The impact, tensile and flexural strengths of the modified one-component epoxy resin are increased by 261.1%, 74.0% and 60.7%, respectively. • The modified one-component epoxy resin features excellent shelf life, rapid curability and transparency. One-component epoxy resins (OCEPs) cured from latent imidazole-based curing agents that exhibit high toughness, high strength, high fire safety, long shelf life, low dielectric properties and transparency are eagerly awaited in advanced manufacturing. However, existing research on latent imidazole-based curing agents/OCEPs mainly focuses on simultaneously improving their flame retardancy and shelf life, but neglects their poor toughness, strength and dielectric properties, and often compromises their transparency. Herein, a hyperbranched polymer (Si-DP) containing P/N/Si was fabricated to further improve the flame retardancy, toughness, strength and dielectric properties of EP10 (the transparent OCEPs comprising the latent imidazole-based curing agent PHI-HPP). EP10 containing Si-DP (EP10/Si-DP) boasted a shelf life longer than 81 days. The synergistic flame-retardant effect of P, N and Si elements enabled EP10/Si-DP3 to achieve a UL-94 V-0 rating with a limiting oxygen index of 33.9 %, the peak heat release rate and total smoke production of EP10/Si-DP5 were reduced by 44.4 % and 25.5 %, respectively, compared with EP10. The increased free volume and Si-O flexible bonds resulted in a 261.1 % higher impact strength of EP10/Si-DP5 than EP10. The excellent interfacial bonding of Si-DP with epoxy resins and the increased rigidity groups led to 74.0 % and 60.7 % higher tensile and flexural strengths of EP10/Si-DP5 than EP10, respectively. The intramolecular cavities and the low-polar Si-C bonds of Si-DP reduced the dielectric constant and dielectric loss of EP10/Si-DP. Meanwhile, EP10/Si-DP maintained inherent excellent transparency and high glass transition temperature (T g). Carbon fiber epoxy composites prepared from EP10/Si-DP5 exhibited remarkable improvement in flame retardancy, smoke suppression as well as mechanical and interfacial performances. Overall, this research proposes an effective approach for preparing long shelf-life OCEPs with excellent overall performance. [ABSTRACT FROM AUTHOR]

In this paper, we propose multiple coating of PET textiles with plasmonic Ag NPs@MXene. Firstly, the synergistic effect between plasma Ag NPs and MXene promotes the photothermal effect of materials. Secondly, Ag NPs reduces the stacking of pure monolayer MXene on textile fibers. Lastly, Ag NPs and MXene appear alternately on PET textile fibers, forming a conductive network with Ag NPs as the connection point. The thermal management textile has high photothermal and electrothermal effects, acid/water stability, flame retardancy, high electrical conductivity and insulation properties. [Display omitted] • The synergistic effect between precious metals and MXene is used to improve the photothermal properties. • Ag@MXene conductive network with Ag NPs as connection points on PET textile fibers was constructed. • We propose to use Ag NPs to alleviate the stacking of MXene on PET textiles. Multifunctional wearable textiles can simulate human perception and convert it into visual data, which has advanced application prospects. As an important branch, thermal management wearable textiles have been widely concerned in the aspects of thermal insulation, flame retardant, photothermal anti-icing, electrothermal deicing and even water evaporation. Here, inspired by the bearing structure, we simply soaked the PET textile in Ag@MXene hybrid solution several times to form a Ag@MXene conductive network with Ag NPs as the connection point on the textile fiber, and finally carry out hydrophobic modification. Based on plasma effect, the synergistic action of Ag NPs and MXene enhances the photothermal response of the material. In addition, the addition of Ag NPs effectively reduces the stacking between MXene layers and forms a Ag@MXene conductive network with Ag NPs as the connection point on the textile fibers. The stable temperature range of PDMS/Ag@MXene PET textile is 70–80 °C under one solar illumination intensity, and the stable temperature of PDMS/Ag@MXene PET textile can reach 117 °C at a constant voltage of 3 V. Based on the excellent thermal effect, this textile achieves photothermal anti-icing, electric thermal de-icing, keeping warm and removing sweat. The textile has a water evaporation efficiency of about 0.58 g h−1, which can achieve excellent anti-sweat function. Finally, the textile also achieved rapid flame retardant within 7 s. PDMS/Ag@MXene PET textile processes excellent photothermal and electrothermal conversion ability, acid/water stability and flame retardant ability, and has promising application prospects in thermal management textiles such as deicing and anti-icing, fire prevention, warmth and water evaporation. [ABSTRACT FROM AUTHOR]

This work presents the fundamentals and applications of a new sustainable lignin-based coating formulation with superhydrophobic and flame-retardant functionalities for wood products. [Display omitted] • Fundamentals of a new sustainable lignin-based coating formulation were discussed. • The material was produced in a solvent-free environment. • The material exhibited superhydrophobic and flame-retardant functionalities. • The material could be used as a wood coating product. There is a tremendous motivation to develop eco-friendly formulas for superhydrophobic and flame-retardant coatings. Presently used coating materials, particularly fluorinated compounds and their organic solvents, are potentially toxic. Here, we demonstrate that a silsesquioxane-grafted kraft lignin (WSL) and aluminum phosphate (AP) binder, i.e., an aqueous sustainable formula, can produce a flame retardant and superhydrophobic coating that is highly resistant to water and solvents. The chemical reaction of softwood kraft lignin (SKL) and aminopropyl/methyl silsesquioxane (WAPMSS) was studied comprehensively. NMR and XPS analyses confirmed the conversion of hydroxyl groups of SKL to Si-O-C via polycondensation. The product exhibited negligible wettability and was very hydrophobic. The dip coating of stain-grade pine wood species in the best formula containing WSL and AP dispersion (1/1 wt./wt.) rendered wood with superhydrophobic (with a water contact angle of (WCA) of 158°) and flame-retardant (with a limited oxygen index (LOI) of 27.2 %) functionalities. The exposure of coated wood to different liquids and high temperatures, as well as abrasion, touching, and knife-cutting analyses, confirmed the excellent durability of the coating formulation on wood. This paper demonstrates an eco-friendly pathway to produce a sustainable wood coating formulation with superhydrophobic and flame-retardant features. [ABSTRACT FROM AUTHOR]

• Pt/m-Al 2 O 3 catalysts were prepared by vacuum impregnation method, which showed good activity and cycling stability. • By using benzaldehyde functionalization and bio-based α-amino-ε-caprolactam, benzyl-protected cyclic lysine was created, converting inexpensive renewable resources into high-value products. • Benzyl-protected cyclic lysine, which is then integrated into nylon-6 polymers, has the potential for antibacterial, flame retardant, and unique thermal properties. Functional nylon-6 polymers, particularly those with special properties such as antibacterial, flame retardant, and specialized thermal properties, have a wide range of applications. However, the efficient synthesis of these polymer monomers has long remained a challenge. Benzyl-protected cyclic lysine (BCL) is a potentially functional monomer, and this article proposes an efficient method for the synthesis of benzyl-protected cyclic lysine on a supported platinum catalyst. Compared to existing techniques, this approach offers higher synthesis efficiency and sustainability. Pt/ m -Al 2 O 3 (microspherical Al 2 O 3) catalysts were prepared using a vacuum impregnation method and showed good activity and selectivity in the production of benzyl-protected cyclic lysine. The conversion rate of α -amino- ε -caprolactam (α -ACL) was 100%, and the selectivity of BCL was 96.0%. The Pt/ m -Al 2 O 3 catalyst maintained good stability over multiple reaction cycles. The reaction mechanism and thermodynamics of functionalized α -ACL were also investigated. The copolymer synthesized with the prepared BCL showed similar structure and thermal stability to pure nylon-6, indicating possible unique functional properties. This study provides a route for the synthesis of cyclic lysine protected with various groups and its potential applications in the field of polymer chemistry. [ABSTRACT FROM AUTHOR]

[Display omitted] Dioctyl terephthalate (DOTP) is the most widely used PVC plasticizer today. However, the poor migration and volatility resistance of toxic DOTP in PVC films lead to hazards for both the environment and human health. Therefore, there is an urgent need to develop a new, environmentally friendly, and multifunctional filler of PVC to improve the overall performance of PVC and reduce the release of toxic DOTP. Here the alkaline and neutral-modified Mg-based layered double hydroxides (PMgLaCe-LDH Ne/Ae) with various La/Ce doping ratios was successfully synthesized through a co-precipitation method and used as multifunctional filler for PVC. Subsequently, composite membranes of PMgLaCe-LDH/PVC were prepared using the blending method, and their comprehensive properties were further investigated. The results demonstrated that the composite membrane, specifically 20Mg10Ce-LDH Ae /PVC, exhibited exceptional qualities. These included improved plasticized flame retardancy, photo-thermal stability, hydrophobicity, low-temperature resistance, volatility resistance, and migration resistance. Furthermore, the short-term and long-term safety evaluation, cytotoxicity assay and intradermal irritation response test on SD rats revealed that the addition of the new environmentally friendly and non-toxic compound, 20Mg10Ce-LDH Ae , effectively inhibited PVC degradation and the release of toxic substances. This research offers a potential solution to mitigate the environmental and health risks associated with PVC products, making them safer and more sustainable. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple self-assembly method for synthesizing rigid-flexible structure PPI with a novel ionic bond. • PPI has excellent compatibility with EP. • Improve flame retardancy and toughness without sacrificing the processability and thermal performance of the EP curing system. • PPI endows CFRPs with excellent mechanical and fire safety performance. Carbon fiber-reinforced epoxy resin (EP) composites (CFRPs), characterized by their lightweight and superior strength, are frequently employed as structural materials in the automotive and aerospace sectors. Nonetheless, the intrinsic flammability and brittleness of EP considerably constrain their use in advanced manufacturing. In this work, a facile self-assembly approach in an aqueous medium between phosphorus-modified polyhedral oligomeric silsesquioxane (P-POSS) and polyethyleneimine formed a rigid-flexible structure PPI with novel ionic bonds. The synergistic flame retardancy effect of P, N, and Si in PPI on EP curing systems and their CFRPs were achieved. The heat release rate, CO production, and total smoke production of EP/7-PPI were reduced by 38.4 %, 44.8 %, and 25.1 %, respectively, and reached UL 94 V-0 grade, illustrating outstanding fire safety performance. Additionally, the rigid-flexible structure of PPI and the presence of ionic bonds facilitated a remarkable improvement in EP fracture toughness, with an increase of 125.1 % in the unnotched impact strength and 50.5 % in the flexural strength of EP/5-PPI. Moreover, relative to CF/EP, CF/EP/5-PPI showed notable advancements in flame retardancy, strength, and toughness characteristics. This study provides an innovative approach for engineering high-performance EP curing systems and their associated CFRPs. [ABSTRACT FROM AUTHOR]

PBAT/3wt C-CS not only shows self-extinguishing, anti-dripping effect, and excellent flame retardant performance, but also demonstrates anti-bacterial, anti-UV properties, and increased crystallizability and hydrophilicity. [Display omitted] • Synthesized fully bio-derived chitosan-based particles (C-CS) enhanced self-extinguishing and anti-dripping effect of PBAT. • Composite (PC3) achieved the highest V-0 fire safety rating and showed excellent flame retardant performance. • Significantly enhanced amount of char residue played a decisive role on enhancement of fire-proofing. • PC3 demonstrated anti-bacterial, lowered UV-transmittance properties and increased crystallizability. Poly(butylene adipate-co-butylene terephthalate) (PBAT), a biodegradable aromatic-aliphatic copolyester, has been widely applied in various fields, but it shows the flammability, resulting in serious fire risk. The flame retardancy of some PBAT/polymer blend systems have been studied, but that of neat PBAT was seldom reported. In particular, the research and development of the bio-based green flame retardant agent is highly desired. In this work, fully bio-derived modified chitosan particles (C-CS), were synthesized and used to prepare a novel PBAT-based multifunctional flame-retardant composite. The PBAT/3%C-CS composite (PC3) exhibited an excellent anti-dripping and self-extinguishing performance and achieved the highest fire safety rating (V-0). Peak of heat release rate and total heat release reduced by 39.8 % and 14.9 %, respectively. The char residue yield of the PC3 increased by 211.6 % in the PC3, compared with that of neat PBAT. Both condensed- and gas-phase played dual roles on increasing the flame-retardant performance of the PC3. The PC3 showed a relatively compact and continuous char layer which acted as a physical barrier to suppress the heat exchange and O 2 entry (into the matrix) in the combustion process. Meanwhile, the concentration of O 2 and H·/HO· free radicals were diluted by a small portion of non-flammable gas products in the pyrolysis process. Also, the PC3 presented elevated crystallizability and anti-bacterial effect, and reduced UV-transmittance characteristic. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel green biodegradable l-lactic acid-based flame-retardant plasticizer was developed. • PDL550 can endow PLA with outstanding flexibility. • PDL550 enhances fire resistance and smoke-suppression of PLA. • The introduction of PDL550 improves the degree of crystallinity and crystallization rate of PLA. Conventional petroleum-based plasticizers not only exhibit reproductive toxicity and non-biodegradability, but their introduction also makes plastics highly combustible. Therefore, the development of biodegradable flame-retardant plasticizers derived from biomass resources can effectively solve the matters mentioned above. In this work, we developed a new l-lactic acid-based biodegradable flame-retardant plasticizer containing phosphorus, nitrogen, and silicon elements (PDL550) with flame-retarded, smoke-suppressing, and plasticized function. The introduction of PDL550 can simultaneously enhance the flame-retardant and flexible performances of polylactic acid (PLA). With the addition of 20 phr PDL550, the PDL550-plasticized PLA blends could pass a UL-94 V-0 grade, and simultaneously its elongation at break increased to 290.32 % in comparison with that of pure PLA (3.70 %). The cone calorimetric tests exhibited that the peak of heat release rate and total heat release of PDL550-plasticized PLA blends, in comparison with that of pure PLA, decreased by 17.8 and 50.8 %, respectively. By analyzing the volatiles and the residual char layer, the phosphorus and silicon elements synergistically in PDL550 are conducive to facilitating the formation of the complete and dense char layer, thus suppressing the release of smoke and shielding the attack of heat. Interestingly, the active soil and tenebrio molitors experiments exhibited that the PDL550 chain was attacked by microbes to form a small aliphatic molecule structure, indicating the excellent biodegradability of PDL550. This study provides an essential reference for developing bio-derived fire-retardant plasticizers to enhance fire safety, smoke-suppressing, and flexible PLA composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combination of bamboo modification and mildew prevention works synergically to achieve mildew prevention of bamboo. • Under the condition that the original structure of bamboo is not changed, the compressive strength reaches 154 MPa. • Synergistically increase the strength and weather resistance of bamboo by in situ hyperbranched molecular design. • The drug loading is only 3.78%, saving on medication.. Despite renewable bamboo globally available and has been applied in industry, the bamboo modification still absents for achieving long-term anti-mildew, stability and desirable toughness, owing to its inherent hierarchical porous structures, that cannot fully insert and retain ideal drugs/polymers. Hence, a hyperbranched polymer (HPB) with polyether as backbone and phenylboronic acid as binding groups via epoxy ring-opening reactions with amino was designed, and subsequently in situ synthesized in the multi-scaled cellular structures in bamboo. It was demonstrated that the hyperbranched polyether chains filled and swollen the hierarchical bamboo cell walls, which could efficiently replace the inner hydroscopic water in bamboo and greatly improved the bamboo stability, resulted in the wet swelling and dry shrinkage rates reduced by 20.3 % and 14.8 %, respectively. Both the side groups of phenylboronic acid and epoxy on HPB outer layers could generate covalent bonding with bamboo cell walls, which twisted the easy-losing facts of boron and gained a 60.6 % retention rate, surpassed most reported modified bamboo literatures and conferred bamboo with good fire resistance and long-time anti-mildew performance. Importantly, with the cavitation effect of HPB to help stress transmission, the modified bamboo had not expensed bamboo strength, instead of reaching satisfied bending strength and toughness at 154.1 MPa of flexure strength and 10.8 % of bending strain, respectively. That expand the industrial application of bamboo. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cellulose-based eutectogel electrolyte (CETG) was designed by hydroxyethyl cellulose and N -methylacetamide/LiTFSI-derived deep eutectic solvent. • CETG exhibited good self-healing and fire retardant properties with an ionic conductivity of 2.04 × 10–3 S cm−1 at 30 °C. • The assembled Li/LiFePO 4 cell showed a capacity retention of 91.8% after 200 cycles at 0.2 C under RT. • The capacity retention rates of assembled batteries achieved 95.2 % and 92.1 %, respectively, after 100 cycles at 0.2 C under 60 °C and 50 cycles at 0.2 C under 100 °C. It is known that the low ionic conductivity of solid - state polymer electrolytes at room temperature (RT) has severely restricted their practical application in lithium-ion batteries. Although eutectogel (ETG) electrolytes could solve this problem to some extent, highly compatible deep eutectic solvent (DES)/polymer systems are desirable to further enhance ion conduction. Herein, we designed cellulose - based ETG (CETG) with dual channels through "hopping" and "vehicle" mechanisms by hydroxyethyl cellulose (HEC) molecular chains and N - methylacetamide (NMA)/LiTFSI-derived DES, respectively. Thanks to the strong molecular interactions between HEC and DES, the highest DES content in the ETG could achieve 90 %, which endowed the CETG with an excellent ionic conductivity of 2.04 × 10–3 S cm−1 at 30 °C. Additionally, our designed CETG displayed good self-healing and fire retardant properties. The assembled Li/LiFePO 4 cell showed a capacity retention of 91.8 % after 200 cycles at 0.2 C under RT with an initial discharge capacity of 156.2 mAh g−1. In particular, the capacity retention rates of the assembled batteries reached 95.2 % and 92.1 %, respectively, after 100 cycles at 0.2 C under 60 °C and 50 cycles at 0.2 C under 100 °C. Our fabrication strategy would provide a novel idea for the design of green, safe and efficient solid-state polymer electrolytes for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• The fire-proof TD-GPE with + 3 and + 5 phosphorus valence states was synthesized via in-situ polymerization. • The TD-GPE shows highly stable cycle performance for NCM811 and LFP full soft pack batteries (1 Ah). • The "jet fire" and leakage were suppressed in the thermal abuse test of NCM811 battery by using flame-retardant TD-GPE. Lithium-ion batteries (LIBs) have been widely used today owing to portability, high energy storage, and reusability. However, commercial liquid electrolytes in LIBs possess intensive mobility and terrible flammability. Accordingly, leakage, combusting, and even exploding can frequently occur when LIBs work under abuse conditions. Herein, a novel flame-retardant gel polymer electrolyte (GPE) containing + 3 and + 5 phosphorus valence states of phosphorus structures was designed by in-situ thermal polymerization of tri(acryloyloxyethyl) phosphate (TAEP), diethyl vinylphosphonate (DEVP), and pentaerythritol tetraacrylate in electrolytes. After being ignited by fire, this GPE extinguished quickly with a combusting time of only 0.9 s, showing much lower flammability. Besides, the GPE is compatible with graphite anode, LiFePO 4 (LFP), and even LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathodes. The as-assembled LFP and NCM811-based pouch cells (1 Ah-type) with TD-GPE achieved stable cycling, maintaining 88.52 % and 95.2 % of the initial capacities, respectively after 200 and 190 cycles at 0.5C. Moreover, the as-prepared TD-GPE dramatically reduced the fire hazard of NCM811 batteries without sacrificing the electrochemical performance. The thermal abuse test demonstrates that the leakage and combustion of NCM811||TD-GPE||Graphite pouch cell could be significantly suppressed in the test process, indicating that battery safety improves significantly via the combined use of different phosphorus valence structures. This is because the + 5 phosphorus valence of TAEP promoted the formation of carbon layers, and the + 3 phosphorus structure in DEVP captured free radicals by quenching effect. This work paves a different path for designing safe and high-performance GPEs in LIBs based on gaseous-phase and condensed-phase mechanisms. [ABSTRACT FROM AUTHOR]

• An innovative strategy towards highly efficient flame-retardant silk. • Modified silk exhibited an excellent flame-retardant property. • ALD-coating of modified silk has a negligible impact on comfortable and wearability properties for silk fiber bulk. • Modified silk shows excellent laundering durability. As a luxurious textile raw material, silk fiber (SF) and its products are widely favored by consumers because of their elegant appearance and excellent comfort. However, their flammability causes potential fire risks and hazards in daily fires and has gained significant attention in recent years. In this work, an ultrathin and uniform TiO 2 , Al 2 O 3 , and ZnO nanofilms with thicknesses of 1 ∼ 200 nm (less than one in a hundred of SF diameter) were deposited on the surface of a silk fabric (SFR) by atomic layer deposition (ALD). By tuning the types of metal oxides and nanofilm thickness, the modified SFR quickly self-extinguished, and its pristine weave was completely preserved after exposure to a flame in a torch burn test, representing superior performance compared to numerous conventional coating technologies reported with higher loadings. An expanded charcoal residue formed on the surface of the modified SFR, acting as a physical barrier that enhanced flame retardancy. Furthermore, the modified SFR showed excellent laundering durability, which helps improve the service life of the fabric. Most importantly, the nanofilms had a negligible impact on the intrinsic comfort and other comprehensive properties of the silk. [ABSTRACT FROM AUTHOR]

• The multifunctional coating of fabric sensor exhibited self-healing performance under near-infrared light irradiation. • The fabric sensor showed flame-retardant property and triggered the fire alarm system within 2 s, enabling sensitive fire alarm responses. • The fabric sensor can detect a variety of human motions. The design of wearable fabric with ultrasensitive fire alarm response and piezoresistive sensor capabilities is urgently imperative to prevent burn injuries to people in the fire accident. Herein, a novel cotton fabric-based piezoresistive sensor comprising hydrophobic waterborne polyurethane, polyphosphazene (PPZ) microspheres encapsulated 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS), and amino-functionalized carbon nanotubes (A-CNTs) was proposed via a roll coating approach, which achieve self-healing, flame-retardant property, and intelligent fire alarm response. The fabric sensor exhibited prominent flame retardancy because of the synergistic formation of a dense flame-retardant layer on the fabric surface by A-CNTs and PPZ. The char residue of the fabric sensor reached 20.4 wt% at 800 °C, and the limiting oxygen index was as high as 27.4 %. Interestingly, benefiting from the thermoelectric characteristic of A-CNTs, the fabric sensor triggered the fire alarm system within 2 s. More importantly, since the resistance changed with their deformations, the fabric sensor can also monitor a variety of human motions, and its sensitivity (GF) can reach 4.79. Additionally, the resulting fabric sensor exhibited self-healing performance. After physical damage, under near-infrared light irradiation, the healing agent FAS spontaneously migrates towards the surface of the fabric, effectively restoring the superhydrophobic property of the fabric. This work provides new insight into the design and application of multifunctional fabric sensors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tetrabromobisphenol A (TBBPA) can be rapidly and deeply debrominated by S-nZVI@LDO. • > 50 % of TBBPA was completely mineralized only by S-nZVI@LDO under ambient conditions. • Electron efficiency of S-nZVI@LDO for TBBPA removal was 2.8 folds of that of S-nZVI. • Dissolved O 2 was activated to produce · O 2 – and · OH for TBBPA mineralization. • The report offers a new method for external oxidant-free in-situ elimination of TBBPA. Tetrabromobisphenol A (TBBPA), currently the most widely used brominated flame retardant, has attracted significant attention. However, traditional methods for deep debromination or mineralization of TBBPA usually include multiple steps and require external oxidants. In this study, we report a complete degradation of TBBPA through a one-step process of only adding a layered double oxide-supported sulfurized nanoscale zero-valent iron (S-nZVI@LDO) under ambient conditions. TBBPA was rapidly removed by S-nZVI@LDO with an efficiency of 95.6 % (10 mg⋅L-1) within 12 h. The kinetic rate constant (0.0035 min−1) was greater when compared with traditional reductants. The produced Br- ion occupied 76.7 % of total Br content, and the concentration of total organic carbon decreased by over 50 %, suggesting a deep debromination and mineralization of TBBPA by S-nZVI@LDO. It is caused by the substantial improvement of electron transfer, O 2 adsorption, and hydrophobicity of S-nZVI@LDO facilitating synchronous reductive debromination and O 2 activation to produce · O 2 – and · OH, as approved by electrochemical test, O 2 -TPO analysis, EPR analysis, and density functional theory calculations. The enriched structural S(−II) and enhanced Fe(III)/Fe(II) redox cycling exerted vital roles in maintaining the reduction potential of the composite. The degradation pathways analysis confirmed that debromination-mineralization mechanisms dominated the complete degradation of TBBPA. This study demonstrates the feasibility of the one-step mineralization removal of TBBPA only using S-nZVI@LDO under ambient conditions and offers insight into external oxidant-free in-situ elimination of halogenated persistent organic pollutants in a natural environment. [ABSTRACT FROM AUTHOR]

A four-tier hierarchical structure is designed which can render fabric with greatly enhanced liquid repellency, self-buoyancy, anti-icing property and flame retardancy, guaranteeing its applications in advanced functional textiles under harsh weather conditions. [Display omitted] • A superamphiphobic and flame-retardant coating with enhanced buoyancy is prepared. • Four-tier hierarchical structures are constructed using multiscale building blocks. • The surface hierarchies are found to be decisive for satisfactory liquid repellency. • The coating shows excellent anti-icing property and tolerance to corrosive liquids. • Various stability tests show that the coating presents high weather resistance. Environmentally robust super-repellent and flame-retardant materials satisfying various functional necessities under harsh weather events to provide protections from fouling and burn injuries have proven challenging to attain. Here, a unique four-tier hierarchical macro/micro/nanostructure is designed and constructed by regulating the accretion of multiscale organic–inorganic hybrid building blocks using silica nanoparticles, microsized ammonium polyphosphate, fluorinated alkyl silane and fluorocarbon surfactants, leading to appreciable self-cleaning, antifouling and anti-icing properties in addition to excellent flame retardancy. The fabricated rough surface exhibits super-repellency to a variety of liquids, including synthetic blood, edible oil, hexadecane, concentrated H 2 SO 4 , and even dodecane. The hierarchy of the surface texture is found to be decisive for satisfactory liquid repellency and weather resistance. In addition, the coated fabric presents an enhanced buoyancy which could load 40.2 times its own weight in water and demonstrates a favorable icing delay time of 1168 s. Various stability tests show that the coating maintains a good nonwetting state even under harsh conditions, including mechanical abrasions, repeated washing, chemical corrosion, heat treatment, and strong ultraviolet irradiation. Thus, this work provides a feasible and sustainable strategy for constructing multifunctional protective materials used in advanced protective clothing, infrastructure and transportation facilities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dynamic E α & A across changing β. • Unique reaction models per degradation stage. • All kinetics via isoconversional & Criados' masterplot technique. • A complements dynamic E α as reaction progresses. In the realm of non-isothermal degradation kinetics, the utilization of multi-heating rate data has unveiled a fascinating distributed apparent activation energy (E α) profile when employing isoconversional methods. The advanced isoconversional method (AIC) emerges as a reliable tool, offering E α values that evolve as chemical reactions progresses. This phenomenon finds its roots in the complex solid-state degradation of plastics, where long-chain hydrocarbons undergo intricate transformations into smaller components through a web of parallel and sequential reactions under the influence of heat. To comprehensively characterize this multifaceted kinetic process, variable pre-exponential factor (A) values were calculated, considering all available heating rate data, in conjunction with the isoconversional principle. These factors complement the changing E α values, providing crucial insights into the evolving material transformations throughout the reaction. Remarkably, our investigation revealed that in the initial degradation stage, centered around the breakdown of Brominated Flame Retardant (BFR), the reaction follows a contracting spherical model (R3). Transitioning to the subsequent stage, the polymer material undergoes degradation following the diffusion model D4. The incorporation of the isoconversional principle and Criados' masterplot technique effectively facilitates the precise determination of all three kinetic parameters. The process layout we present holds considerable promise for advancing the understanding and control of complex kinetic phenomena. [ABSTRACT FROM AUTHOR]

[Display omitted] • A flame-retardant and photo-thermal microstructure is synthesized. • Thermochromic materials and bio-based flame retardants are used as core and shell. • Heat release and smoke production are effectively suppressed. • The melting and slide of ice block is accelerated by solar-thermal conversion. Due to the extreme dynamic weather, important industrial facilities and infrastructure providing vital support for people's lives usually face the hazards of fire and icing, especially in the weather of thunderstorm and ice. Therefore, to further establish a safe community, we develop a dual-functional polyurea (PUA) coating used as protective materials by introducing flame retardancy and solar de-icing performance. Based on the microencapsulation and electrostatic self-assembly technologies, flame-retardant and thermochromic microcapsules (TCM) are firstly prepared and then added into PUA resin, by using melamine resin and bio-based phytic acid/chitosan (PA/CS) hybrids as double-shell materials. The high phosphorus content of PA and the carbon-forming effect of CS together play a synergistic flame retardant effect, not only improving the thermal stability of microcapsules but also enhancing the flame retardant property of PUA coating. In the cone calorimetry test, the ignition time of TCM@PA/CS@PUA-3 is longer, and the pHRR is reduced by 19.93 %, which shows the improvement of flame retardant performance. Due to the thermochromic mechanism, TCM@PA/CS@PUA composite coatings are able to adjust the photo-thermal conversion ability according to different environment temperature, achieving less temperature in hot environment and higher temperature in cold environment. The excellent photo-thermal conversion ability also promotes the ice melting and slide in 525 s. This polyurea composite coating with both flame retardant and de-icing properties shows great potential for maintaining the normal operation and safety of outdoor industrials and infrastructure in extremely dynamic weather conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work focuses on the sustainability and safety of radiative cooling materials. • Bio-based chitosan and phytic acid are used to prepare radiative cooling film. • The radiative cooling effect and fireproof performance are presented simultaneously. Even though significant advantages in the energy-free regulation of temperature are presented, the practical applications of radiative cooling materials in buildings and human surfaces still involve many safety issues, especially for fire hazards of polymer-based materials. Meanwhile, renewable and environmentally friendly materials are urgently needed to develop suitable radiative cooling materials with no adverse environmental impact. Herein, a chitosan-derived composite aerogel film with high solar reflection provided by the addition of melamine-phytic acid (MA/PA) hybrids is designed and prepared, presenting radiative cooling and fireproof performances. The instinct deep-yellow color of chitosan (CS) is successfully shielded by high-reflective MA/PA hybrids, while IR emissivity of up to 90.4 % and solar reflectivity of ∼ 89.3 % are achieved. In outdoor environments, this composite aerogel shows sub-ambient temperature drops of ∼ 4.3 °C and ∼ 3.1 °C in cloudless and cloudy weather, presenting a robust cooling effect. In addition, CS-MA/PA composite aerogel film with 3 mm thickness can isolate the fire of ∼ 500 °C, showing superior fire safety attributed to the synergistic flame retardant effects among chitosan, phytic acid, and melamine, which suppress the initial growth of fire and promote the rapid formation of protective char layer. This work provides a bio-based, fire-safe, and radiative cooling material to decrease the energy consumption of temperature regulation with a more environmentally friendly and safer approach, further promoting the practical application of radiative cooling materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel 0D@2D coating is designed by hybridizing carbon dots (CD) mixture on MXene. • CD mixtures from waste fruits are hybridized directly with MXene, reducing energy waste. • The coating is stably constructed on the fabric via a simple one-pot impregnation method. • Trace impurities in CD mixtures positively impact flame retardancy of the coating fabrics. • The coating fabric incorporates flame retardancy, conductivity, sensing and durability. With the rapid development of the smart era, there is an urgent need to replace traditional cellulosic textiles with flame retardant multifunctional cellulosic textiles. Herein, two novel multifunctional textiles (MXene@CDG-C/L and MXene@CDM-C/L) were obtained by constructing coatings consisting of MXene and bio-based carbon dot mixtures (CDG and CDM) on cellulose fabrics using a one-pot impregnation method. MXene@CDG-C/L and MXene@CDM-C/L exhibited desirable flame retardancy, electrical conductivity and sensing properties due to the synergistic effect of MXene and carbon dot mixtures. In the vertical burning test, MXene@CDG-C/L and MXene@CDM-C/L showed self-extinguishing when the external ignition source was removed, with limiting oxygen index values increasing from 18.1 % of untreated fabric to 34.4 % and 36.0 %, respectively. Meanwhile, the conductivities of MXene@CDG-C/L and MXene@CDM-C/L were as high as 31.8 S m−1 and 21.4 S m−1, respectively. Notably, benefiting from the inherent flexibility of cellulose fabrics, MXene@CDG-C/L and MXene@CDM-C/L were able to monitor human movement in a stable and continuous manner. In addition, MXene@CDG-C/L and MXene@CDM-C/L retained good integration properties including flame retardancy, electrical conductivity and sensing property after 20 washing cycles. In conclusion, the strategy reported in this work provided a new idea for the development of environment-friendly and economical multifunctional smart textiles. [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]

[Display omitted] • Hyperbranched polysiloxane coating provided great protection for PP against fire. • APTES was used as a film-forming agent for creating a cross-linked structure. • The coated PP achieved a UL-94 V-0 rating and an LOI value of 37.8 %. • The coating is highly flexible, adhesive, and resistant to water and UV radiation. • The coating maintained the mechanical properties of the PP substrate. In general, the addition of flame retardants may lead to the degradation of the mechanical properties of polymers, despite enhancing their flame retardancy. However, flame-retardant coatings have the potential to provide good flame resistance to polymers without compromising their inherent mechanical properties. In this study, we applied highly adhesive and flexible polysiloxane flame-retardant coatings (196 μm) to polypropylene, resulting in reductions of 74.9 %, 58.0 %, 80.0 %, and 56.4 % in peak heat release rate, peak smoke production rate, fire growth rate, and mass loss, respectively. By incorporating the lab-synthesized DOPO-modified polysiloxane (APID), the flame-retardant efficiency of ammonium polyphosphate (APP) was greatly enhanced. The primary film-forming agent, (3-aminopropyl) triethoxysilane (APTES), played a key role in maintaining the compatibility of APP and APID with the coating, as well as facilitating the formation of a robust Si O Si crosslinked network structure that strengthened the resulting char layer. The interactivity between the various components, including hydrogen bonds and crosslinked network structures, contributed to improved uniformity, thermal stability, and adhesion of the coatings. Moreover, the coatings exhibited resistance to ultraviolet radiation and water. Our findings suggest that highly flexible and adhesive flame-retardant coatings hold significant potential for applications in polymer protection. These promising results provide a viable pathway for improving the fire protection of polymers through the use of high-adhesive intumescent flame-retardant coatings. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phosphonitrile-functional MXene enhances fire safety and mechanical properties. • Highly effective smoke suppression, 33.3% reduction in total smoke production. • The back of the laminate remains at 430 °C when the front is exposed to 1500 °C. • Exceptional impact strength, 29.3% increase compared to BMI/CF. • Excellent tensile strength, 33.3% increase compared to BMI/CF. Bismaleimide (BMI) resin holds great significance to the aerospace field, however, the limited toughness and inadequate fire resistance impede its broader application area. The addition of carbon fiber (CF) can enhance the toughness of BMI resin, but fire safety and interfacial stability between CF and BMI matrix need to be further considered. Here, the carbon fiber-reinforced BMI resin laminate was designed to improve fire resistance, mechanical properties, and interfacial affinity based on a novel P, N, and Si surface-modified flame retardant (MX@HBET) and silane-modified CF. Upon addition of 1 wt% MX@HBET to BMI/CF composites, the total heat release and total smoke production respectively exhibited 10.73 % and 33.3 % reduction. Furthermore, the laminate exhibited significant fire resistance when exposed to butane flame (1500 °C) and the backplane temperature was maintained at approximately 430 °C for 20 min. In addition, the impact and tensile strengths of the laminate respectively reached 82.10 kJ/m2 and 466.6 MPa (pure BMI/CF corresponding to 63.52 kJ/m2 and 350.1 MPa). In brief, the flame resistance and mechanical performance enhanced greatly via the introduction of modified MXene and CF, providing promising prospects for the application of aviation materials in extreme conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • The "three-in-one" starch-based intumescent flame retardant is used as precursor. • Porous carbon is rapidly prepared by flame burning carbonization strategy in air. • The porous carbon formation mechanism is confirmed via in-situ FT-IR and TG-FT/IR. • The starch-based K 2 CO 3 -glycol-DMSO DES gel electrolyte (2.2 V) is synthesized. • Assembled capacitor exhibits high performance and wide operates temperature range. Exploring novel methods for preparing porous carbon is essential for developing electrode materials. Herein, a general strategy for preparing porous carbon via flame-burning carbonization of a three-in-one intumescent flame retardant (IFR) is proposed. The IFR comprising biomass (starch, agar, cotton fiber, and cottonseed meal as carbon sources), Zn 3 (BO 3) 2 (as an acid source) and K 2 CO 3 (as a gas source) is carbonized directly by a flame gun in 5 min to prepare porous carbon. The carbon layer is formed by esterification, depolymerization, ring opening, polycondensation and aromatization. Concurrently, the molten state of the boron and potassium compounds prevents the carbon from burning out. Benefited from the doping, templating, and activating effects of Zn 3 (BO 3) 2 and K 2 CO 3 , the samples exhibit a layered porous structure and multi-heteroatom doping, demonstrating excellent capacitive properties. The starch-based K 2 CO 3 -glycol-DMSO deep eutectic solvent gel electrolyte is synthesized, and the fabricated solid-state capacitor exhibits high energy density (24.5 Wh kg−1), a large voltage window (2.2 V), and a wide temperature operating range (-25 °C to 75 °C). Moreover, the four types of IFRs are amenable to the proposed burning carbonization method, and it is expected that diverse carbon materials will be synthesized using other IFRs in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyester with bis-phosphaphenanthrene pendants as multifunctional flame retardant for EP. • Modified EP showed superb overall performance, particularly toughness and strength. • Modified EP exposed high fire safety with low addition. • Simultaneous achievement in transparency, UV shielding and dielectric properties. To ameliorate the inherent deficiencies of epoxy resins (EP) and to achieve flame-retardant EP with comprehensive performance for versatile applications, a phosphorus-containing polyester named PEDP with rigid-flexible spacers and bis-phosphaphenanthrene pendants was designed, prepared and successfully applied to EP as polymeric flame retardant with multifunctionalities. The obtained EP-PEDP thermosets did not show phase separation to achieve a high dispersion of PEDP and enhanced interaction between two components, which effectively improved the mechanical properties of the thermosets. EP-PEDP displayed excellent toughness, with impact toughness, fracture toughness K IC and G IC reaching 30.9 kJ·m−2, 1.27 MPa·m1/2 and 0.67 kJ·m−2, respectively, showing 166.4 %, 28.3 %, and 59.5 % greater than neat EP; yet tensile and flexural strength also increased rather than sacrificed. The combined flame-retardant action of PEDP in gaseous and condensed phases effectively improved the self-extinguishment and greatly suppressed the release of smoke and heat during burning to achieve high fire safety of EP-PEDP. In addition, EP-PEDP also possessed high glass transition temperature, satisfactory thermal stability, transparency with UV shielding capacity, as well as good dielectric and thermomechanical properties. The design and synthesis of this multifunctional phosphorus-containing polyester with a rigid-flexible integrated nature, which integrates mechanical enhancement, serves as a promising polymeric flame retardant for high-performance EP to meet diverse requirements. [ABSTRACT FROM AUTHOR]

[Display omitted] • A synergistic hyperbranched polymer (HPTDM) was synthesized to improve the flame retardancy and toughness of BMI. • The modified bismaleimide composites had high thermal stability. • The BMI/HPTDM-0.5 with the phosphorus content of as low as 0.05 wt% could achieve a maximum reduction of 34.4% in THR. • The impact strength of BMI/HPTDM-1.0 was 90.2% higher than the pure BMI. Usually, the incorporation of traditional linear molecule flame retardant will bring negative impact on the thermal stability of bismaleimide (BMI), which limited the application of BMI in high-end fields. Based on this problem, a synergistic hyperbranched polymer (HPTDM) containing phosphorus/nitrogen/silicon was used as a novel flame retardant for cured BMI system. Due to the specific hyperbranched structure, the HPTDM itself had high thermal stability. And the elements of nitrogen, silicon and phosphorus can significantly improve the efficiency of flame retardants through synergistic effects. Surprisingly, the addition of flame retardants did not greatly affect the thermal stability of pure BMI, and the BMI/HPTDM-0.5 with the phosphorus content of as low as 0.05 wt% could achieve a maximum reduction of 34.4% in total heat release (THR). Furthermore, the modified BMI resin demonstrated superior toughness owing to the novel hyperbranched structure, and the impact strength of BMI/HPTDM-1.0 was 90.2% higher than the pure BMI. This article provided a novel strategy for designing hyperbranched flame retardant and promoted the BMI in the field of high temperature. [ABSTRACT FROM AUTHOR]

• In-situ assembled APz@ZIF67 provided whole-process fire prevention from pyrolysis to flaming; • APz@ZIF67 exhibited synergistic enhancement in LOI and bending strength other than APP; • Highly-porous ZIF67 absorbed toxic gases and helped suppress smoke during combustion; • ZIF67 inspired foamed char layer for burnt strandboard locking gas evacuation. Wood strandboard as a typical green building material is facing challenges as for its low fire safety. Conventionally applied flame retardants such as ammonium polyphosphate (APP) have limitations due to insufficient smoke control and adverse effects on the mechanical properties of strandboards. Herein, a core–shell structure flame retardant (APz@ZIF67) was synthesized by growing Co2+ on the surface of piperazine-modified APP (APz). At a same loading level of 10 wt%, the properties of strandboards containing APP, APz, and APz@ZIF67 were specifically analyzed and compared with untreated boards. It's found that APz@ZIF67 exhibited synergistic enhancement of strandboards both in mechanical and flame-retarding properties other than APP or APz. APz@ZIF67 modified strandboards showed increased bending strength and modulus by 70.37 % and 19.65 %, respectively. Strain migration analysis by digital image correlation disclosed the higher stress transfer efficiency. Meanwhile, the limiting oxygen index of strandboards increased by 71.37 %, reaching 48.55 %. The mean heat release rate decreased by 48.61 %, and the total smoke rate decreased by 43.78 %. APz@ZIF67 helped patch the cracks in wood cells, preventing the evacuation of heat and gases through the char layers on the surface of burnt strandboards. Additionally, the highly porous ZIF67 attached to APz reduced production of toxic gases during the pyrolysis process of wood strands. The above findings confirm the potential applicability of metal–organic frameworks (MOFs) in enhancing intumescent flame retardants, and provide a state-of-the-art pathway to manufacture fire-safety wood composites with balanced mechanical properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • RP is transformed into a 2D lamellar structure by a simple method. • PUA composites (PUA/2D RP@ZIF) exhibit excellent flame-retardant properties. • The compatibility of the 2D RP@ZIF and PUA matrix is good. • The mechanical properties of PUA/2D RP@ZIF are improved compared to PUA. Red phosphorus (RP) is a promising polymeric flame retardant due to its abundance of flame-retardant elements. Unfortunately, the irregular size of RP leads to poor dispersion in polymer matrices, which greatly limits its wide application in flame-retardant polymer materials. Here, RP is transformed into a two-dimensional (2D) lamellar structure by a simple green method, while ZIF-67 nanoparticles are grown in situ and uniformly embedded in them. The 2D porous RP@ZIF (2D RP@ZIF) composites exhibit excellent flame-retardant properties and mechanical properties in polyurea (PUA) matrix. The peak heat release rate, total heat release, the peak of smoke production rate and total smoke production of PUA composites added with 5 wt% 2D RP@ZIF decreased by 48.0 %, 54.2 %, 20.4 % and 22.2 %, respectively. Due to its well compatibility, the elongation at break and tensile strength of PUA composites were 308.02 % and 9.21 N in the mechanical test, respectively. Compared with previous work, this is the first time that a 2D RP hybrid flame retardant has been prepared by metal organic framework and applied to flame retardant PUA. [ABSTRACT FROM AUTHOR]

[Display omitted] • The multifunctional bio-based P, N-containing polyphosphazene flame retardant (PAHP) is designed. • PAHP acts synergistic flame-retardant effect in both the gas and condensed phases. • PAHP exhibits evident toughness enhancement effect on PLA. • The flame retardant and UV resistance properties of PLA is achieved. Polylactic acid (PLA) is inherent brittle, flammable, and susceptible to ultraviolet light irradiation, limiting its application in the field of engineering safety. Therefore, advanced PLA composites with toughness and flame retardancy as well as other exceptional engineering performance has garnered significant interest. In this work, a versatile additive (PAHP) was synthesized by nucleophilic substitution utilizing flexible chain (polyphosphazene) as the skeleton and rigid biomass compound (guanine) as a substituent, then fabricating all-in-one PLA composites. The PAHP plays a synergistic flame-retardant role in both the gaseous and condensed phases, improving the flame retardant performance of the composites while effectively enhancing the crystallization and mechanical properties of PLA. Only 5 wt% PAHP within PLA composite can meet the fire-safety requirements of engineering applications (V-0 rating of UL-94) and exhibits a ∼12-folds enhancement in toughness compared to neat PLA. Moreover, the PLA/5% PAHP composite shows excellent ultraviolet shielding effects, blocking approaching 100 % UV isolation under UV-B wavelengths. This work offers a scalable strategy for preparing multifunctional flame-retardant additives, opening up a great promise for the application of high-performance PLA engineering composites in packaging, electronic, and automotive. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dual network interpenetration strategy significantly improves impact toughness. • Exceptional fire shielding performances, ∼32.8 % reduction in total heat release. • 48.4% decrease in total smoke production and LOI of 34.5% are achieved. • The optimized composite material has a dielectric constant as low as 2.67. The high-frequency transmission of 5th-Generation Mobile Communication Technology (5G) and more integrated mobile terminals pose a challenge to the safety and dielectric properties of existing electronic packaging materials. This work innovatively designs a linear polyphosphazene compound (PABN) with benzonitrile as the reactive side group. The prepared bismaleimide (BMI)/PABN is an excellent dielectric composite material, breaking the technical barrier of balancing fire safety and dielectric performance. With only 1 wt% PABN, the UL94 rating of BMI composite reaches V0, and the impact strength increases by 48.5 %, demonstrating excellent fire safety and toughness. Specifically, the dielectric constant (D k) of the composite containing 4 wt% PABN is as low as 2.67, far meeting the requirements of 5G. In addition, the glass transition temperature (Tg) of all BMI/PABN composites is around 290 °C, and the initial decomposition temperature exceeds 400 °C, indicating potential applications in the integration and miniaturization of microelectronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Trifluoromethyl radicals are proposed as flame retardant radicals. • The flame-retardant mechanism of trifluoromethyl radicals is proposed. • Data support is provided for the applications of DGEBAF in fireproofing, electronic packaging, and other fields. • A novel approach is proposed for the analysis of fire safety. In order to obtain epoxy resins with flame retardant, dielectric properties, and easier industrialization, thus meeting the future development requirements in the field of electronic encapsulation, a trifluoromethylated epoxy resin (DGEBAF) was synthesized by using a two-step method, and the cured epoxy resin (DGEBAF/DDM) was prepared with DDM as the curing agent. Detailed studies of DGEBAF/DDM including curing kinetics, mechanical properties, and dielectric properties, etc. were conducted by using DGEBA/DDM (with dimethyl structure in DGEBA) and DGEBF/DDM (with dihydrogen structure in DGEBF) as the comparative samples. The results indicate that DGEBAF/DDM has higher storage modulus and strength, better dielectric properties, and hydrophobicity, and lowest thermal expansion coefficient, due to the existence of trifluoromethyl. Importantly, deeply study about the flame retardancy and its mechanism of DGEBAF/DDM was processed, which was of great significance for its application in the field of electronic packaging. Its vertical combustion level reaches UL-94 V-0. The limiting oxygen index of DGEBAF/DDM is 34.5 %, which is improved by 35.8 % and 30.2 % compared to DGEBA/DDM and DGEBF/DDM, respectively. The thermal decomposition mechanism of DGEBAF was explored by Py-GC/Mass, XPS, and FTIR analysis. It can be inferred that trifluoromethylated epoxy resin releases •CF 3 at high temperatures and effectively enhances the flame retardant of the epoxy resin through radical trapping. The smoke toxicity of DGEBAF/DDM combustion was detected in real time by conical thermal method combined with gas infrared analysis. In addition, we have found that DGEBAF/DDM decomposes at first but produces most residual carbon among the three epoxy resins. Based on the characteristics, an intelligent fire alarm system was designed. [ABSTRACT FROM AUTHOR]

• Green and sustainable development: using vanillin as bio-based raw material. • Multifunction: easily reprocessing, ultrafast degradation rate, high recovery rate. • Safety: great flame retardancy with V0 rating in UL-94 test and LOI value of 29%. With the development of a circular economy and sustainable environment, efficient and sustainable recycling of useful chemicals from thermosets is of great significance. However, most commercial thermosetting materials are difficult to reprocess, degrade, and recycle due to their permanent cross-linked network, and the preparation process consumes much fossil energy and causes serious environmental pollution problems. Furthermore, the high flammability makes them unsafe during service life and limits their applications. Herein, we used renewable lignin derivative vanillin as bio-based materials to synthesize a trialdehyde monomer (TMP) with phosphorus element and developed the bio-based polyimine dynamic networks with excellent comprehensive properties including outstanding reprocess ability, degradation recyclability, and fire resistance performance based on polyetherimide and 4-aminophenyl disulfide. The prepared bio-based polyimine materials with the dual dynamic networks (BPDNs) exhibited outstanding mechanical property with tensile strength of 61.6 MPa, super-rapid degradation rate and high monomer recovery rates of 70.5 %. The prepared BPDNs samples showed great flame retardancy with V0 rating and V1 rating in UL-94 vertical burning test and high LOI value of 29 %. Moreover, BPDNs could be reprocessed within 10 min at elevated temperatures (150 °C). This work provides a very effective method to prepare bio-based advanced thermosetting materials with multiple functions. [ABSTRACT FROM AUTHOR]

[Display omitted] • MD-ReaxFF and experiments were utilised to study the flame retardant(FR) mechanisms. • The pyrolysis hindrance offered by the FRs is elucidated by increasing C/H ratio. • FR chemistries such as dehydration, radical capture and charring were characterised. • Novel removal techniques were employed to predict char residue of HDPE and HDPE/FR. Localised flame-retardant (FR) chemistry of polymer composites is complex, versatile and microscopic depending on the combination of polymer matrix and various FR systems. Particularly, the pyrolysis behaviour of the polymers can be varied and reinforced by effective microscopic synergistic effects between coating compositions. However, these atomistic reactions can be difficult to be characterised via experimental approaches. In this study, experimental studies and reactive molecular dynamic (ReaxFF-MD) simulation techniques were utilised to identify the thermal degradation behaviour of flame retarded high-density polyethylene (HDPE), coated with phosphoric acid (PA) and pentaerythritol (PER). The simulations tracked the pyrolysis product distribution under different heating temperatures and elucidated the pyrolysis hindrance offered by the FR system. The atomistic reaction pathways of phosphorus-based FR mechanism were also characterised, including secondary reactions and intermediate species, such as P-O-C and P-O-P cross-linking between FRs and radical capturing effects. These reactions were found to be increasing the C/H ratios of pyrolysed hydrocarbons and the aromaticity of residues. After applying the periodic removal techniques, the simulations can even predict the residue weight percentage of the polymer and exhibit similar degradation behaviour to the experimental results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of six novel phosphorus-containing liquid reactive flame retardants. • Low viscosity, flame retardant and toughened vinyl resin for CF composites. • Valence state and group of phosphorus affect the flame retardant mechanism. The traditional flame-retardant method for carbon fiber reinforced vinyl ester resin composites is to add a large amount of solid flame retardants, which not only leads to the deterioration of the material's mechanical properties, but also increases the resin viscosity and affects the molding process of composites. In addressing this issue, this work adopts a liquid reactive flame retardant strategy and synthesizes six novel liquid phosphorus-containing reactive compounds as flame retardants. A comparative study is conducted on the effects of the structure of compounds (valence and group of phosphorus and number of reaction groups) on the properties of materials. The results demonstrate significantly improved flame retardancy and toughness, as well as unaffected viscosity and strength of the resin. When the phosphorus content does not exceed 3 wt%, the limiting oxygen index (LOI) of the resin can reach over 30% and UL-94 passes the V-0 rating. The structure of compounds significantly affects their flame retardancy mechanism. Especially, compounds rich in P-O-C structure have more outstanding condensed phase flame retardancy (promoting charring) and are more favorable for improving the LOI; Compounds rich in P-Ph and P-C structures have higher thermal stability and mainly exert gas phase flame retardancy, which is more beneficial for improving the self-extinguishing properties of materials. Furthermore, a synergistic flame retardant effect is observed between carbon fiber and compounds rich in P-Ph. [ABSTRACT FROM AUTHOR]