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Water pollutions that come from spilled oils, discharged organic reagents and abused pesticides have become an urgent problem to ecosystem. In this study, inspired by the multi-properties of MOF materials, we presented a bifunctional MOF-based sponge (OPA-UiO-66 @MF) to achieve the effective oil/water separation as well as the catalytic degradation of organic pollutants. On one hand, upon the in-situ growth of UiO-66 on melamine foam (MF) sponges and the octadecyl-phosphonic acid (OPA) modification of UiO-66, we highlighted the superhydrophobic/superoleophilic property of the OPA-UiO-66 @MF, which leads to excellent performances in oils adsorption and continuous oil/water separation. On the other hand, benefits from the lipase-like property of UiO-66, OPA-UiO-66 @MF was proved having potential ability in the catalytic degradation of carboxylic acid ester pesticides which are usually enriched in oils or organic solvents. Moreover, since phosphorus containing groups can be introduced onto the surface of sponge through OPA modification, OPA-UiO-66 @MF also displayed superior flame resistance. As an effective, safe and green material, the developed flame-resistant bifunctional OPA-UiO-66 @MF sponge might provide a promising application in the elimination of organic pollutants in water systems. [ABSTRACT FROM AUTHOR]

To address the issues of formaldehyde emission, mildew, and easy combustion of traditional wood adhesives, this paper, for the first time, reported formaldehyde-free plywood bio-adhesives using carbonaceous material (hydrochar) generated from hydrothermal carbonization (HTC) of glucose with or without acrylic acid (AA) and acrylamide (AM). The highest wet shear strength of bio-adhesives (BD-G/AA-180) was 1.32 MPa, which meets the Chinese national standard GB/T 9846-2015 (≥0.7 MPa). It was found that functional groups (–NH 2 and –COOH) were abundant on the surface of hydrochar from co-HTC of glucose with AM or AA. The formation of covalent bonds (between components of bio-adhesives; between bio-adhesives and wood) via dehydration or esterification reaction was a key factor in improving wet shear strength during hot-press treatment. Unlike bio-adhesives developed from polysaccharides and proteins, these hydrochar carbonaceous material-derived bio-adhesives had excellent anti-mildew properties and flame resistance with help from ammonium polyphosphate. This work paves a new road to prepare green formaldehyde-free plywood bio-adhesives. [Display omitted] • Use of glucose hydrochar to prepare bio-adhesives was reported for the first time. • Covalent bonds via dehydration or esterification were key to wet shear strength. • Functional groups on the surface of hydrochar improved bio-adhesive performance. • Hydrochar-based bio-adhesives had excellent anti-mildew properties. [ABSTRACT FROM AUTHOR]

Flame resistance is required for the deployment of bio-based materials, especially those forming cellular structures that endow thermal insulation. This study proposes a one-pot strategy to prepare cellular lignocellulosic composites with excellent flame resistance. Lignocellulosic microfibers were used as the substrate onto which a flame-retardant complex consisting of P-containing phytic acid (PA) and N-containing polyethyleneimine (PEI) was formed. Following the prediction of ab initio molecular dynamics simulation, PA and PEI are integrated onto MF-CTMP following a single-step complexation assembly triggered by pH effects. The PA-PEI modified MF-CTMP can be readily transformed into a composite solid foam by dewatering a wet foam followed by oven drying. At the expense of a slightly reduced thermal insulation (thermal conductivity increase from 33.6 ± 0.6 to 40.0 ± 0.6 mW/(m·K)) the presence of PA-PEI complexes significantly improved the mechanical performance of the foam and uniquely endows it with flame resistance. Compared to unmodified MF-CTMP foams, the composite foams showed significant improvement in the Young's, specific compression, and flexural moduli (increased by 13.5, 5.5, and 7.3 folds, respectively), a high oxygen index (up to 40.8 %) and self-extinguishing effects. The results suggest the suitability of the introduced lignocellulosic foam as an alternative to traditional synthetic polymer-based counterparts as well as inorganic matter for insulation, particularly relevant to the building sector. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nacre-like ternary hybrid network TA-GO/HHACP is facilely constructed. • The network shows excellent mechanical and flame resistance property. • Ultra-sensitive early fire alarm response of ∼ 1 s at temperature of 250 °C is achieved. • Ultra-long continuous fire alarming period of > 1600 s is realized. • Flame-retardant mechanisms and reliable fire warning behaviors are clarified. Graphene oxide (GO)-based intelligent fire alarm sensor (FAS) has recently been a sought-after research topic in fire prevention fields. However, it remains a challenge to facilely construct GO-based composite that simultaneously possess mechanical flexibility, excellent flame resistance, highly-sensitive temperature-responsive behavior, rapid fire response and ultra-long fire alarming durability. Here, a nacre-like ternary hybrid paper is conveniently obtained by integrating GO with hexachlorophosphazene-based multi‑hydroxyl molecule (HHACP) and tannic acid (TA) via a facile and eco-friendly water evaporation-induced self-assembly method. The resultant composite paper (TA-GO/HHACP) exhibits mechanically flexible property with tensile strength of 103.7 MPa and toughness of 1.51 MJ/m3, comparable to 2.52 and 5.39 times higher than those of pure GO paper. Further, the TA-GO/HHACP paper displays excellent nonflammability and high-temperature resistance that can withstand continuous butane flame attack (∼ 1200 °C), resulting in ultra-long sustained alarming period of > 1600 s under an open fire. More importantly, benefiting from its rapid electrical resistance reduction capability, such TA-GO/HHACP paper demonstrates ultra-fast fire-triggered response time of ∼ 0.6 s, and ultra-sensitive early fire alarm responses to abnormal high temperatures during pre-combustion process, e.g., ∼ 1 s at 250 °C and ∼ 19 s at 200 °C, respectively, outperforming the best reported GO‑based FAS counterparts. This work provides an inventive paradigm to develop high-performance GO-based intelligent materials with reliable and sensitive early fire-warning function. [ABSTRACT FROM AUTHOR]

Cellulose is now considered as an appealing environment friendly material for the development of sustainable separators for rechargeable batteries. This study thus aims to develop high performance paper based ceramic separators with superior electrolyte wettability (>170 %), high thermal stability (>200 °C) and excellent flame safety. While developing paper based ceramic separator, extensive studies are carried out to understand thenature and functionality of different nano-structured ceramic materials (Al 2 O 3 , BaTiO 3 and ZrO 2) impregnated in paper matrix. Nano-ZrO 2 facilitates an effective pathway for Li +-ion transport (t Li + = 0.51), whereas BaTiO 3 and Al 2 O 3 ceramics show moderate Li +-ion transport properties (t Li+ of 0.29 and 0.30 respectively). Electrochemical Impedance Spectroscopy (EIS) measurement clearly reveals that ZrO 2 exhibits more interfacial compatibility with the electrodes (MCMB and LiNi 1/3 Mn 1/3 Co 1/3 O 2) compared to the other two ceramic separators during full cell operation. The developed paper separators show excellent electrochemical properties in terms of cycling (tested 300 cycles), multi-electrode compatibility and rate capabilities at different current densities of 0.1–1.2 mAcm−2. The pre- and post-electrochemical EIS data reveal that ZrO 2 based impregnation offers significantly lower charge transfer resistance compared to the other two separators. The study thus demonstrates a real promise for its successful application in Li-ion battery towards achieving sustainability and safety. [Display omitted] • Sustainable, flexible and high safety ceramic based paper separators for LIBs. • Separators were developed using easy to scale up wet-coating process. • Ceramic impregnation affects physical and electrochemical properties of the separators. • Paper separators show superior electrolyte wettability and high thermal stability. • Better electrochemical performances and flame safety are other important advantages. [ABSTRACT FROM AUTHOR]

The mechanical shock and thermal damage generally exist together in hazardous environment, whereas traditional single protective materials are difficult to achieve all-round protection under extreme environment. Herein, to realize the integration of multifunctional abilities about impact resistance, flame-retardant and sensing performance, a "solid-liquid host-guest" structural shear thickened composite sponge is proposed, which flame-retardant shear thickening fluids with an extraordinary thickening ratio of 2183.95 % continuously disperse in 3D sponge matrix. The resulting composite sponge effectively attenuates the impact force by nearly 80 % with the thickness of only 4 mm via a cooperation between the effect of shear hardening and structure densification. Meanwhile, after burning on the alcohol flame for 12 s, the composite sponge with 7 wt.% fire-retardant additive maintains a complete morphology and realizes self-extinguishing with a reliable flame-retardant ability. Attributed to the good electrical conductivity of shear thickening fluid, the composite sponge serves favorably in human body monitoring, impact sensing and fire warning. In a word, this multifunctional lightweight composite sponge is expected to realize the integration of early warning and protection, which is a competitive candidate material for the intelligent protection in complex environments. [Display omitted] • A new type of conductive shear thickening fluid was prepared. • The sensing performance endows P-STF sponge with human body monitoring function. • The P-STF sponge protects against both impact and thermal hazards. • The P-STF sponge achieves the integration of protection and early warning. [ABSTRACT FROM AUTHOR]

Carbon nanotubes, presenting distinguished electromagnetic wave (EMW) loss capacity and light-weight advantage, are promising candidates for EMW absorption materials. However, poor dispersibility, inadequate processibility, and excessive permittivity leading to impedance mismatch limit the application of carbon nanotubes. Herein, branched aramid nanofiber (ANF) acting as a surfactant, gelling agent, and electromagnetic parameter regulator is utilized to ameliorate the performances of carboxylic multi-walled carbon nanotube (c-MWCNT). The c-MWCNT/ANF aerogels with anisotropic structures are assembled through electrostatic-repulsion-assisted dispersion, hydrogen-bond-induced gelation, unidirectional freezing, and freeze-drying. By adjusting the proportion of c-MWCNT and ANF to optimize the impedance matching and electromagnetic parameters, the composite aerogel with ultralow density (∼26.2 mg cm−3) shows an extraordinary minimum reflection loss of −60.43 dB and a maximum effective absorption bandwidth of 5.34 GHz along the vertical direction of oriented channels. Moreover, benefiting from high porosity and remarkable thermal stability, the aerogels possess prominent thermal insulation and flame resistance. This work provides a strategy for the advanced EMW absorption materials, which have great potential value for aerospace applications under harsh environments. [Display omitted] • ANF ameliorates the dispersibility and electromagnetic parameters of c-MWCNT. • Anisotropic and multifunctional c-MWCNT/ANF aerogel was prepared. • The reflection loss and effective absorption bandwidth reach −60.43 dB and 5.34 GHz. • The aerogel has ultralow density, thermal insulation, and flame resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The multifunctional conductive HPCF was prepared using a layer-by-layer deposition method. • The resulted HPCF possess great superhydrophobic and flame retardancy. • The obtained HPCF can transmit distress signals and realize water rescue. • The HPCF shows rapid detection response for flame within 1 s. • The smart fabric is useful for multifunctional wearable electronic textile. Smart fabrics provide considerable inspiration for the construction of wearable electronic devices due to their excellent skin affinity and breathability. However, the limited tolerance to high humidity environments and the flammable nature of fabrics impedes broader practical applications. In this paper, by an advanced and effective method, phytic acid doped (PA-) polyaniline (PANI) was polymerized in-situ on cotton fabric deposited by carbon black (CB), and then modified by non-fluorine hydrophobic particles, a flexible breathable fabric-based strain sensor (HPCF) with ultrahigh moisture resistance, flame retardancy and environmental resistance was successfully prepared. The obtained sensor shows high sensitivity (16.14 kPa−1) in the detection range of 0–2 kPa, fast response/recovery time (82/40 ms) and high cycle stability (>10,000 cycles). Thanks to its excellent hydrophobicity (WCA = 153°) and flame retardancy properties, the material enables the detection of human movement (such as finger/wrist/elbow/knee/foot movement) under a variety of harsh conditions (extremely high temperatures, underwater, acid, alkali, salt and blown sand environments). More importantly, it can be further applied to remote detection of potentially dangerous scenarios. HPCF can successfully transmit the Morse code signals of "SOS" and "HELP" sent by drowning people, and realize water rescue. In case of fire, it serves as a fire warning sensor to realize agile (1 s) fire alarming. The highly sensitive and versatile HPCF fabric sensor enables physical condition monitoring for fire and rescue personnel working in high temperature and humidity environments, which is of great value for all human activities carried out in harsh environments. [ABSTRACT FROM AUTHOR]

Flame-retardant silane-grafted-graphene oxide (silane-GO) papers are fabricated via a green and versatile silane-assisted assembling strategy, and their use as early fire alarm sensors are investigated. Different silane molecules with alkoxy groups can react with GO in aqueous solution via hydrolysis and condensation reactions and thus assemble into the aligned silane-GO papers. The silane-GO papers exhibit good mechanical flexibility, strong acidic/alkaline tolerance, excellent flame resistance and improved thermal stability at low silane content in comparison with pure GO paper. Structure observation and analysis disclose that a compact nano-silica protective layer transformed from the grafted silane molecules during combustion is formed to inhibit the thermal degradation of GO sheet effectively. Furthermore, the insulating silane-GO paper can be thermally reduced into the conductive reduced GO network after encountering high-temperature or flame situation, thus providing ideal early fire alarm response, i.e. rapid flame detecting response time of ∼1.6 s and fire early warning response of ∼5 s when attach on the heat resistor. These results suggest that the silane-GO papers are promising for development of advanced materials as smart sensors in early fire alarm applications. A facile and green silane-assisted assembling technique was developed to fabricate flame-retardant graphene oxide papers, showing fast flame detection and ideal early warning response. Image 1 • A facile silane-assisted assembling strategy was developed to fabricate flame-retardant graphene oxide (silane-GO) papers. • Different silane molecules with alkoxy groups were assembled well onto the aligned silane-GO papers. • The silane-GO papers exhibited good mechanical flexibility, strong acidic/alkaline tolerance, and excellent thermal stability and flame resistance. • The related flame-retardant mechanisms were analyzed and discussed. • The silane-GO papers showed fast fire alarm response due to temperature-triggered sensitive resistance transition, showing promising for fire safety and prevention. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Hybrid latex with 50 wt. % MTS are prepared through emulsion polymerization. • Three different structure latex are obtained by controlling addition steps of MTS. • The properties of the hybrid latex films are significantly enhanced. Abstract In this paper, high content methyltrimethoxysilane (MTS) (50 wt. %)/polyacrylate composite colloidal particles with different structures are successfully synthesized through emulsion polymerization and the storage period can reach 2 years. The polyalkylsilsesquioxane matrix distribution on the surface of the composite colloidal particles can be easily controlled by changing the order of addition process steps of MTS in system, as shown in TEM. DSC results show that the effects of the order of addition process steps of MTS on the T g of the polymer can be neglected. Thermal stability of the composite colloidal films is improved, as proved by TGA results. The hydrophobicity, water adsorption resistance and flame resistance of the composite films are distinctively enhanced after MTS is incorporated into the system. Transparency of the composite colloidal films is as good as that of the pure polyacrylate film. [ABSTRACT FROM AUTHOR]

A cheap and effective flame retarded EPS system was developed by using a high silica content based fly ash (FA) synergistic with aluminum hydroxide (ATH) in the thermosetting phenolic resin (PF) coating layer. In this study, scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analyses confirmed the formation of a barrier layer which uniformly encapsulated each EPS microsphere. The flammability of EPS-PF/ATH/FA foam with different compositions were characterized by the limited oxygen index (LOI) and UL-94 vertical burning tests, an evident flame retardant effect has been observed with up to 29.6% LOI value and UL-94 V-0 rating. The cone calorimetric analysis (CONE) indicated that the heat release rate (HRR), total heat release (THR) and smoke production rate (SPR) of the resulting EPS-PF/ATH/FA foam decreased obviously, and the foam maintained structural integrity after combustion. The thermal stability of EPS-PF/ATH/FA foams has been evaluated by the thermogravimetric analysis (TGA). It is obvious that the presence of PF-ATH/FA flame retarded binder has delayed the pyrolysis process of EPS matrix by about 10 °C. From analysis conducted on the combusted residues, it can be inferred that the dominant flame retardant action of EPS-PF/ATH/FA foam occurred in the compact char layer, which acted as an effective fire-proofing and heat shielding barrier in the condensed phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 5-hydroxymethyl-2-furaldehyde derived epoxy resin monomer (HMF-PDMS-EP) was developed. • The bio-based epoxy system showed a record T g of 207 °C, high strength and modulus. • The bio-based epoxy system showed satisfactory intrinsic flame retardancy. • The bio-based epoxy system showed recyclability in carbon fiber composite. A new renewable material, comprising a Schiff base epoxy thermoset derived from furan derivatives, was successfully synthesized. This innovative material not only possesses remarkable carbon fiber recyclability but also exhibits favorable mechanical properties and flame retardancy. After being cured with the bio-based curing agent, 5,5′-methylenedifurfurylamine, the cured Schiff base epoxy thermoset exhibited an ultra-high char yield of 54% and a glass transition temperature of 207 °C. Compared to bisphenol A epoxy resin, it achieved a 100% higher yield. Furthermore, the cured Schiff base epoxy thermoset demonstrated a high storage modulus (at 30 °C) of 2695 MPa and a tensile modulus of 60 MPa, surpassing bisphenol A epoxy resin. Remarkably, the exceptional structure of the Schiff base epoxy thermoset imparted intrinsic flame retardancy, resulting in a V-0 rating in the UL-94 test. The thermoset also exhibited considerable recyclability in carbon fiber composites due to its Schiff base network. Moreover, it could be nondestructively and quickly recycled under mildly acidic conditions, enabling efficient recycling of the carbon fiber composites. [ABSTRACT FROM AUTHOR]

The formalized polyvinyl alcohol fibers (PVF fibers) were grafted with acrylic acids after being activated in dilute potassium permanganate solution, and then the grafted PVF fibers (PVF-g-AA fibers) were reacted with melamine formaldehyde (MF) oligomer solution to form flame-retardant coatings on their surface. The coated PVF fibers (PVF-g-AAMF fibers) were further treated with copper sulfate solution for absorbing copper ions to promote their flame retardant performance. The structure of the fibers was characterized by FTIR spectra and SEM photos. The flame-retardant performance of the fibers was evaluated by limiting oxygen index (LOI) and microcalorimeter tests (MCC tests). It is found that MF coatings effectively improved the flame resistance of PVF fibers, but the flame retardant efficiency was not satisfactory. Copper ions have an obvious synergistic effect on the flame resistance of the fibers. SEM photos of char residues, results of TGA and TG-IR revealed that the flame retardance of MF coatings is mainly due to gaseous phase.The effect of copper ions on the thermal decomposition of MF resins was analyzed with pyrolysis-gas chronograms-mass spectrometry (PyGC-MS), and it is found that copper ions catalyzed the thermal decomposition of MF resins, which synchronized the decomposition of MF resins and PVF fibers. Copper ions are also effective in improving the char residues of PVF-g-AAMF fibers. The flame resistance of the fibers was improved dramatically by the synergistic effect between the grafted MF resin and the copper ions. [ABSTRACT FROM AUTHOR]

A series of isocyanate-based flexible polyimide foams were prepared with different isocyanate indices. The structure and properties of these polyimide foams were characterized in detail. The results indicated that with the increase of isocyanate index, the density decreased from 8.7 kg/m 3 to 5.7 kg/m 3 . The open cell ratio was in the range of 94.9%–96.4% and less influenced by the content of isocyanate. The compression strength increased first with the increase of isocyanate index, and reached the maximum value at an isocyanate index of 1.04. All the polyimide foams possessed excellent thermal stability, with temperature at weight loss of 5% and 10% being in the range of 288.5–320.0 °C and 337.7–369.0 °C, respectively. The limiting oxygen index (LOI) values for all the samples were above 25%, indicating the high flame resistance character of polyimide. The heat release peak values, the total heat release and mean heat release rate exhibited similar trends of little changes with isocyanate index varying from 0.89 to 1.04 and increasing rapidly with the index more than 1.11, indicating the side products of amino or uramido produced by excess isocyanate would damage the flame resistance properties of polyimide foams severely. [ABSTRACT FROM AUTHOR]

A novel super-artificial hair fiber basing on sodium alginate (SA) and Antarctic Krill protein (AKP) was prepared by wet spinning successfully. Such SA/AKP fiber did not only have similar crystalline structure with human hair, but also had super flame resistance and mechanical performance. It should be noted that the whole preparation process was green without any incorporation of non-toxic solution. Moreover, comparing with human hair, the SA/AKP fiber had a lot of unique groove upon the fiber surface, which contributed a lot to excellent hygroscopicity. Meanwhile, the dyeing performance could be improved notably due to incorporation of protein into the matrix. Herein, the SA/AKP fiber with superior mechanical and functional performance had practical value for application in the field of synthetic wig. [ABSTRACT FROM AUTHOR]

As one of a series of our studies, starting with silica sol (TM2) and Si-P binary sol (SP5), two series of low-hydroxyl-content sols (LHCSs) were synthesized using an anhydrous sol-gel method. The stable storage time of LHCS-containing hybrid coatings was improved relative to that of hybrid coatings containing TM2 and SP5. The flame resistance and thermal stability of UV-cured hybrid coatings consisting of LHCS, epoxy acrylate of bisphenol A (SM6104) and tripropylene glycol diacrylate (TPGDA) were investigated by means of thermogravimetric analysis (TGA), limit oxygen index (LOI), cone calorimetry and a flammability test. The results indicated that the flame resistance of LHCS-containing hybrid coatings was further improved over that of hybrid coatings containing TM2 and SP5. The improvements mainly included a longer ignition time and lower combustion heat. Hybrid coatings applied on the surface of wooden floors could offer long-lasting and significant protection against fire, showing outstanding practical value. In addition, the physical and mechanical properties of LHCS-containing hybrid coatings were negatively affected by the decrease of hydroxyl group contents and the Ti-containing component. A UV-curable phosphorus-containing resin (RAYLOK 1722) was introduced into the hybrid coatings containing LHCS. However, hybrid coatings containing RAYLOK 1722 showed only a small improvement in flame resistance, and their physical and mechanical properties were damaged by RAYLOK 1722. [ABSTRACT FROM AUTHOR]

In this work, the β-cyclodextrin (β-CD) was modified by a phosphazene compound to prepare a novel amorphous derivate (β-CDCP), which was combined with the ammonium polyphosphate (APP) as a synergistic flame retardant (FR) of the bio-based poly(L-lactic acid) (PLA). The effects of the APP/β-CDCP on the thermal stability, combustion behavior, pyrolysis process, fire resistance performance and crystallizability of the PLA were investigated comprehensively and in depth by thermogravimetric (TG) analysis, limited oxygen index (LOI) analysis, UL-94 test, cone calorimetry measurement, TG-infrared (TG-IR), scanning electron microscopy-energy dispersive spectrometer, Raman spectroscopy, pyrolysis-gas chromatography/mass spectrometry and differential scanning calorimetry. The PLA/5%APP/10%β-CDCP showed a highest LOI of 33.2 %, passed V -0 rating and exhibited self-extinguish phenomenon in the UL-94 test. Also, it presented a lowest peak of heat release rate, total heat release, peak of smoke production rate and total smoke release, and a highest char yield treated by cone calorimetry analysis. In addition, the 5%APP/10%β-CDCP shortened significantly crystallization time and enhanced crystallization rate of the PLA. Gas phase and intumescent condensed phase fire proofing mechanisms are proposed to elucidate enhanced fire resistance in this system in detail. • Modified β-CD (β-CDCP) was synthesized successfully with microsphere-like structure. • PLA/5%APP/10%β-CDCP showed the highest LOI, achieved V-0 level and exhibited self-extinguish phenomenon. • PLA/5%APP/10%β-CDCP presented intumescent char layer to enhance fire proofing performance. • 5%APP/10%β-CDCP extremely enhanced crystallizability of PLA. [ABSTRACT FROM AUTHOR]

• Eco-friendly, flame-resistant acoustic panel for low frequency sound absorption. • Utilization of coir fiber and rice husk wastes as fibro-granular material for acoustic panel. • Incorporation of RHA-replaced cement binder constituting 70% by weight of fibro-granular material. • Around 86 % sound waves are absorbed within the frequency domain 500 Hz–5000 Hz. • Noise reduction coefficient at four octave bands (250 Hz, 500 Hz, 1000 Hz and 2000 Hz) was 0.76. Natural fibers, when used as passive sound absorbers, appear to be effective in absorbing medium and high frequency sound waves, but are weak in absorbing low frequency sound waves; sometimes a major challenge to design engineers and architects. This study investigates the possibility of using fibro -granular acoustic panel for the absorption of low frequency sound waves through an experimental approach. The incorporation of fibrous materials, coir fiber and granular material, rice husk combined with rice husk ash-replaced cement binder in these panels reduces the toxicity of commonly used binders such as phenol formaldehyde, polyester foams and polyurethane. The sound absorption coefficient of these panels was tested in an impedance tube and also in an anechoic room. The flame resistance of the fibro-granular material was also tested. The results show that the developed panels with density 200 kg/m3 are effective in absorbing both low and high frequency sound waves within the acoustic frequency range 100 Hz −5000 Hz with a noise reduction coefficient > 0.4.The sound absorption coefficient of these panels was compared with that of commercial sound absorbers and was found to be better. In addition, significance of parameters influencing low frequency sound absorption of these panels were determined statistically. The eco-friendly acoustic panel made of agricultural residues does not require large capital investments. On the other hand, the disposal of these agricultural residues would incur operational cost coupled with health hazards. The incorporation of these waste materials in this eco-friendly acoustic panel would thus be economically beneficial to our society. [ABSTRACT FROM AUTHOR]

[Display omitted] • Liquid monomers enable bulk polymerization via one-pot parallel reactions. • The new strategy readily affords novel interpenetrating polymer networks. • The resin fluctuates with hardeners showing a twist-stacked or planar weave matrix. • The viscoelastic, dielectric, mechanical behaviors and flame retardancy are enhanced. • Aerobic or anaerobic pyrolysis selectively favors the IPN upcycling into graphene. The 5-hydroxymethylfurfural, honokiol, and magnolol are converted into sustainable epoxy monomers, i.e. , 5,5′-(((3′,5-diallyl-[1,1′-biphenyl]-2,4′-diyl)bis(oxy))bis- (methyl-ene))bis(2-((oxiran-2-ylmethoxy)methyl)furan) (MGHF) and 5,5′-(((5,5′-diallyl-[1,1′-biphenyl]-2,2′-diyl)bis(oxy))bis(methylene))bis(2-((oxiran-2-ylmethoxy)- methyl)furan) (MGMF), and they are finally cured by 3,3′-diamino diphenylsulfone (33DDS) and 4,4′-diamino diphenylsulfone (44DDS), thus affording novel interpenetrating polymer networks (IPN). Interestingly, 33DDS induces a twist-stacked structure, whereas 44DDS provides a planar weave matrix. As to the twist-stacked layout MGMF/33DDS, it behaves a superhigh storage modulus (∼5.04 GPa), a high phase transition temperature (T g , 222.7 °C), and an elevated onset temperature (T d5 , 362.8 °C). For planar weave arrays, MGHF/44DDS shows the highest values in T g (224.9 °C), lap shear strength (∼20.4 MPa), hardness (∼508 MPa), and reduced Young's modulus (∼6.06 GPa). Furthermore, MGMF/44DDS shows an excellent dielectric property (11.15, 0.02) (∼1 kHz, 25 °C) and a moderate thermal conductivity (0.355 W (m·K)−1) alonging with increased flame retardancy. Besides, those biobased epoxy resin wastes are reclaimable through aerobic or anaerobic pyrolysis. Anaerobic pyrolysis of planar weave networks selectively yields more doped graphene, whereas similar event readily happens to the aerobic pyrolysis of the twist-stacked polymers. In view of these reported advantages, this novel strategy opens new avenues for multifunctional epoxy resins. [ABSTRACT FROM AUTHOR]

[Display omitted] • STF is prepared by ionic liquids and SiO 2 with good thermal stability. • The STF/Kevlar composite has good high temperature resistance. • The STF/Kevlar composite protects against both impact and thermal hazards. • The composite has a wide application prospect in extreme environments. The impact and thermal damage in extreme environments generally exist together. In this context, the design of safety protection materials ought to consider not only the single impact protection performance, but also thermal stability and flame resistance. In order to simultaneously achieve the impact resistance, thermal stability and flame resistance properties, a flexible and lightweight shear-hardened composite material (STF/Kevlar) was prepared by impregnating and drying shear thickening fluid (STF) on Kevlar fabric. Due to the favorable shear thickening performance of shear thickening fluid, STF/Kevlar composite material can increase the maximum yarn pull-out force of the fabric yarn from 3.3 N to 16.3 N with the impregnation weight gain of 55 wt%. Moreover, in bullet impact experiment, a single layer of STF/Kevlar fabric can nearly double the time it takes a bullet to penetrate pure Kevlar fabric. Additionally, STF/Kevlar composite material exhibits significant flame resistance as well. The limit oxygen index can reach 32 %, and after 30 min high temperature treatment at 400 °C, the composite still maintains good mechanical property and flexibility. This multi-functional composite material along with the performance of resisting both mechanical shock and thermal damage in extreme environments is expected to broadly apply in the field of lightweight protection. [ABSTRACT FROM AUTHOR]

[Display omitted] • Obtention of novel thermosetting copolymers with high-performance applications. • Polysilsesquioxane-based structures enhance the mechanical and thermal resistance of the polymeric matrices. • Hybrid polybenzoxazine/polysilsesquioxane structures show laminar nanosized morphology. • Benzoxazines results in good curing agents for epoxy resins to prepare benzoxazine/epoxy copolymers. This work focuses on the development of novel thermosetting systems derived from a siloxane-based benzoxazine hybrid precursor [Pr(BA-3aptms)], a conventional benzoxazine (BA-a) and a commercial epoxy resin (DGEBA) based on bisphenol A, as a strategy to prepare benzoxazine/benzoxazine and epoxy/benzoxazine copolymers with different amounts of polysilsesquioxanes in their chemical structure. The effect of the siloxane composition on the morphology was investigated, and their influence on the thermal, dynamo-mechanical and flammability properties was elucidated. The obtained results allowed to conclude that an increase of the BA-a or DGEBA content in the copolymers, considerably affects the morphology of the materials. In this sense, the laminar arrangement changed to a nanocluster arrangement when the contents of Si were below 17% w/w for the epoxy/benzoxazine and below 10% w/w for benzoxazine/benzoxazine systems, respectively. Also, the thickness of the organic sheets in the matrices was increased when increasing the content of BA-a or DGEBA in the materials. In addition, the incorporation of the polysilsesquioxane-based precursor in the crosslinked materials improved the investigated properties, such as: thermal, mechanical and flame resistance, and hydrophobic behavior. [ABSTRACT FROM AUTHOR]

• A bio-based γ-ray-degradable epoxy HBN bearing phenyl imine conjugated N N bonds was synthesized. • The thermoset was formed by curing HBN and a hardener with the same sensitive group. • The thermoset with high contents of the sensitive group can be efficiently degraded. • The thermoset exhibit excellent mechanical and fire-resistance performance. With the growing awareness of energy consumption and environmental pollution, the development of γ-radiation-degradable technology derived from clean energy is of great concern. However, radiation-induced degradation for thermoset materials is limited because γ-radiation-induced radicals are prone to recombination rather than controlled cleavage. Herein, via introducing the radiation-sensitive groups, phenyl imine conjugated N N bonds, we synthesized a radiation-sensitive epoxy monomer from vanillin (a renewable source) and 4-hydroxybenzhydrazide. The thermoset was formed by crosslinking this bio-based epoxy monomer with our reported hardener bearing phenyl imine conjugated N N bonds. When treated by a stimulus of γ-ray radiation, the resulting epoxy thermoset with high contents of sensitive groups could be efficiently degraded at a dose of 10 kGy. Degradation of the thermosets are realized through the controlled cleavage of phenyl imine conjugated N N bonds. Benefiting from this stable conjugated structural design, the epoxy thermosets exhibit excellent mechanical performance and intrinsic flame resistance with a tensile strength over 70 MPa and a limited oxygen index (LOI) of 35.1 %, which are higher than those of traditional robust thermosets made from bisphenol A. This work not only renders a pioneering paradigm of bio-based γ-ray-degradable thermosets but also develops an effective approach to simplify the manufacturing process of fire-safe thermosets, which significantly enhance the versatility of polymer materials. [ABSTRACT FROM AUTHOR]

Biodegradable cellulose films with excellent mechanical, optical, and functional properties have attracted considerable attention as promising alternatives to plastics for photoelectronic devices. In this work, mechanically ductile, flame-retardant cellulose films with tunable optical properties were prepared by simple mechanical disintegration of phosphorylated cellulose (PhC) fibers, vacuum filtration of as-prepared dispersions, and subsequent pressing of the wet PhC films to prepare dried films. When mechanical disintegration conditions were optimized, the resultant PhC films exhibited an average density, tensile strength, Young's modulus, tensile toughness, and folding resistance of 1.4 g/cm3, 150 MPa, 8.5 GPa, 8.2 MJ/m3, and 4580 times, respectively. The PhC film hazes were widely controllable from 9 % to 91 %, while they maintained high light transmittances (>90 %) at a 550-nm wavelength. The PhC films were used for light management of light-emitting diodes by controlling mechanical fibrillation conditions of the PhC fiber/water slurry, showing that the films effectively improved the luminescence uniformity of the devices. [Display omitted] [ABSTRACT FROM AUTHOR]

• Tailored functional films show a low-temperature response to a fire within 1 s. • A Warning message is shown on multiple computer monitors 20 km from a fire source. • FPU wrapped the pre-designed solution is used for sensitive fire sensor. Fire sensors are highly promising in maintaining public fire safety. However, it has certain deficiencies in sensitivity and intelligence even after its development for several years. Developing an advanced fire sensor remains a considerable challenge. This work proposes a novel early thermos-sensitive fire sensor based on phosphorous (P) / silicon (Si) - decorated graphene oxide (GO) by layer-by-layer assembly (LBL) technology. This early-warning film can achieve an ultrafast response within 1 s at a low temperature of 250 °C or an actual fire during the simulation scenario. Intriguingly, an intelligent custom-made wireless communication system is designed to show warning messages on multiple local and long-range computer screens at distances up to 20 km from the target fire area. Furthermore, the pre-designed functional solution can be a fire-warning nano-coating layer wrapped into flexible polyurethane (FPU) foam. This illustrates the feasibility of tuning novel fire-warning nano-coating onto flammable FPU for fire sensors. These results may provide new insights into advanced smart low-temperature fire-warning coating strategies and a new generation of wireless combined fire sensors. [ABSTRACT FROM AUTHOR]

Traditional lithium-ion batteries based on liquid electrolytes cannot adapt to the increasing and various highly flexible requirements. In this work, a confinement-driven strategy has been developed to confine the ionic liquids in a polyhedral oligomeric silsesquioxanes (POSS) and poly(ethylene glycol) diacrylate (PEGDA) hybrid cross-linked poly(ionic liquid)s ionogel (POSS-CPIL-n), which endows this novel electrolyte superior flame retardancy and dramatically flexibility. The POSS-CPIL-n ionogel renders exceptional flexibility (bend, fold and twist) and desired mechanical properties (2.5 MPa). Advantageous for high dissociation of lithium salt, high ionic conductivity (2.5 mS cm−1 at 25 °C) and considerable lithium ion mobility (0.51) are provided. Thanks to the flexibility of ionogel electrolyte together with excellent thermal and electrochemical stability, the LiFePO 4 ||Li cell based on POSS-CPIL-n exhibits significant rate performance and cycling stability, the capacity of the cell can reach to 100 mAh g−1 at 4 C and maintain a substantial discharge capacity of 160.5 mAh g−1 after 200 cycles at 0.2C. Furthermore, the soft-package assembled with POSS-CPIL-n can successfully charge a cell phone and continue to supply power stably even when the battery is exposed to the air, which indicates that POSS-CPIL-n has a promising potential application in high safety flexible electronic devices. [Display omitted] • POSS-CPIL ionogels with double cross-linking system were successfully prepared. • The ionogel has multi-function in mechanical, thermal and electrochemical properties. • POSS-CPIL-based flexible cells show great potential for practical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multifunctional ionomer (sSEBS-Ce) is rationally designed and synthesized. • 1.5 wt% of sSEBS-Ce obviously increases the fire resistance and toughness of PC. • The tensile strength and transparency of PC/sSEBS-Ce are well-preserved. • Structure-composition-property correlation of sSEBS-Ce in PC is revealed. Polycarbonate (PC) features high transparency and balanced mechanical properties, and thus is being growingly used for producing many high-end products, e.g. , construction facades, sensors and 5G equipment. For these applications, PC is required to combine satisfactory fire retardancy and great toughness while retain its mechanical strength and optical transparency. However, existing either fire retardants or toughening agents fail to enable PC to achieve such a required performance portfolio due to their improper molecular designs. To overcome this challenge, we, herein, rationally design a series of sulfonated ionomeric fire retardants (sSEBS-M, M = Na+, Zn2+, Ce3+) by sulfonating and neutralizing styrene-ethylene-butylene-styrene (SEBS). The sSEBS-M can be well-dispersed within the PC matrix with phase domain sizes less than 500 nm. Chemical structures of sSEBS-M and their dispersion within the polymer matrix strongly correlate to their comprehensive performances in PC. Among three sSEBS-M ionomers, sSEBS-Ce endows PC with better comprehensive performances. With 1.5 wt% of sSEBS-Ce, the final PC achieves a high limiting oxygen index of 33.5% and a desired UL-94 V-0 rating, in addition to a 53% reduction in peak heat release rate and a comparable transparency to virgin PC. Moreover, its impact toughness and ductility are enhanced by 40% and 116% with tensile strength well-preserved. The integrated performance portfolios are superior to previous counterparts. This work offers a novel strategy for the design of multifunctional ionomer-based fire retardants for creating high-performance PC and reveals its structure-composition-property relationship in PC, which will enable PC to realize its practical applications in above-mentioned industries. [ABSTRACT FROM AUTHOR]

Abstract: Environmentally friendly, colorful, and flexible electrospun polyacrylonitrile (PAN)–carbon nanotubes (CNTs)–ochre (Oc) nanofibers (as-spun, stabilized) with very high flame resistance (heat release capacity of 24–143 J g−1 K−1, total heat release of 2.1–8.7 kJ g−1, char yield of 55–74%, limiting oxygen index of 22.5–34.5%) and mechanical properties (ultimate tensile strength of 80–177 MPa) were produced using a mineral, non-toxic, economic Oc and CNT in 1% CNTs and 10% Oc based on polymer concentration from a predominant synergistic effect between CNTs and Oc. This approach using a mineral material is an environmentally friendly method which may possibly solve a number of problems related to materials science and economics such as improving a flame resistance and lowering the cost for various applications in automobile, protective textile, and other areas. [Copyright &y& Elsevier]

Abstract: The boron-containing phenolic fibers were prepared by melt-spinning a mixture of novolak resin and boron acid followed by curing the filaments with formaldehyde solution in the presence of an acid catalyst. The resulting fibers were heat-treated in N2 at elevated temperatures. The results show that the addition of 1.0wt% boron acid in the precursor resin can greatly increase thermal stability, mechanical strength and flame resistance of the resultant fibers. In comparison the boron-containing phenolic fibers with the pure phenolic fibers, the weight loss of the boron-containing phenolic fibers (BPF-1.0), heat-treated at 240°C for 2h, decreases from 60.5 to 39.1% in N2, from 32.8 to 14.1% in air. Whereas, the limited oxygen index increases from 32.5 to 37.2%; the tensile strength increases from 129.3 to 163.4MPa. [Copyright &y& Elsevier]

• A green flame retardant COPD is synthesized by COS, p-hydroxybenzaldehyde and DOPO as raw materials via two-step reaction. • COPD improves significantly inflaming retarding properties of PLLA and keeps its environmental friendliness. • Multi-armed PCL is incorporated to balance the flame resistance and mechanical property of the composite. A green flame retardant COPD is synthesized by using chitosan oligosacc- haride (COS), p-hydroxybenzaldehyde and 9,10-dihydro-9-oxa-10-phospho-10-oxide (DOPO) as raw materials according to two-step reaction. The synthesized product is confirmed with FTIR, UV and NMR. When the COPD is inserted into poly(l-lactic acid) (PLLA) via solution blending, the flame retardation of PLLA is improved. As the blend ratio of COPD/PLLA is 20/80, the limit oxygen index (LOI) and UL-94 vertical burning grade 25% and V-1, respectively. The heat release rate (HRR), total heat release (THR), and average effective heat release (av-EHR) decrease in conical calorimetry. The composite also exhibits good carbon forming capacity. The flame retardation mainly originates from cooperation of condensation phase with gas phase process. Since the poor miscibility limit the dispersibility of COPD in PLLA matrix, the flame resistance and mechanical performance of composite are to compromised. The flame retardation for PLLA is anticipated due to green raw material is used and alternative process such as melt blending and adding compatibility can be adopted. [ABSTRACT FROM AUTHOR]

[Display omitted] • TBP and [BMMIm][NTf 2 ] act as the mixed solvent of organic-ionogels. • TBP reduces the viscosity of the solution and enhances ionic conductivity. • Organic-ionogels are hydrophobic and flame retardant. • Organic-ionogels exhibit high stress sensitivity and apply in flexible touch screens. Very different from electronic conductors, ionic conductors usually possess some unique functions such as stretchability, transparency and ionic conductivity, thus exhibiting a great promise in the flexible wearable electronic devices. Herein, we develop a novel stretchable transparent organic-ionogel (OIG-TBP-50) via a rapid photo-curing process, in which we select the mixture of tributyl phosphate (TBP) and 1-butyl-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl)amine ([BMMIm][NTf 2 ]) as fireproof and conductive solvent, respectively. Just benefiting from the good synergistic effect of TBP and [BMMIm][NTf 2 ], our-designed OIGs demonstrate excellent hydrophobicity and flame resistance as well as perfect stretchability (757%), high transparency (93%) in visible region, good environmental stability, wide temperature tolerance range (from −55 °C to 180 °C) and high ionic conductivity (1.73 × 10-3 S cm−1 at room temperature). In addition, our stretchable transparent OIGs even could light LED lamps under an alternating current field when directly used as the flexible conductive substrate. Further applying such OIGs as ionic conductor to assemble flexible sensor and touch screen, both of them could transport rapid signal response under slight touch stress. [ABSTRACT FROM AUTHOR]

Abstract: The diepoxide of bishydroxydeoxybenzoin, termed BEDB, was prepared and used as a diepoxide in adhesive formulations with various aromatic diamine cross-linkers. These novel epoxy resins were characterized and compared to the properties of bisphenol A (BPA)- and 3,3′,5,5′-tetrabromobisphenol A (TBBA)-based epoxies in terms of their thermal and mechanical properties. Cured formulations were characterized to determine glass transition temperatures by differential scanning calorimetry (DSC). The char residue, heat release capacity, dynamic mechanical properties, fracture toughness, and adhesion strength of the cured resins were investigated by thermogravimetric analysis (TGA), microscale combustion calorimetry, dynamic mechanical analysis (DMA), plain-strain fracture toughness tests, and lap shear tests. The BEDB-based resins exhibited significantly higher fracture toughness and adhesion strength compared to the BPA-epoxy resins, as well as low heat release properties (i.e., lower flammability) despite the absence of halogen. [Copyright &y& Elsevier]

Abstract: Poly(methylmethacrylate) (PMMA) shows high strength and transparency but is a flammable material. In this study, the surface of aluminum hydroxide was modified with methacrylate containing phosphoric acid moieties before dispersion in MMA, and organic–inorganic nano-hybrid materials were obtained by bulk polymerization in the presence of the surface-modified aluminum hydroxide. The resulting hybrid materials retained the high transparency of PMMA, with transparency values similar to that of pure PMMA. Moreover, the flame resistance of the hybrid materials was improved in comparison with that of pure PMMA, with depression of the horizontal burning rate becoming a maximum at an inorganic content of 3wt%. These results suggest that the use of aluminum hydroxide surface-modified with phosphoric acid groups is an efficient method for obtaining good performance fire-resistant polymer materials. [Copyright &y& Elsevier]

Organic–inorganic hybrid materials were prepared starting from tetraethoxysilane and α- or α,ω-triethoxysilane terminated poly(ϵ-caprolactone) (PCL–Si) using the sol–gel process. In all cases the formation of nanocomposites with a high level of interpenetration between organic and inorganic phases was noted. Poly(methyl methacrylate) slabs were dip-coated with PCL–Si/silica hybrids and a very strong increase of the flame resistance (also after UV irradiation) was noted for all coating compositions without marked differences with respect to hybrid compositions. This behavior was attributed to a preferential segregation of silica onto the outer surface, as evidenced by XPS analysis. [Copyright &y& Elsevier]

[Display omitted] • A novel tree-like gel membrane based on PVDF/lamellar OMMT nanofiber is prepared. • Excellent flame-retardant is enhanced with incorporation of OMMT in PVDF TLNM. • Superior ion conductivity can be obtained due to gel state of membrane and lamellar OMMT. • The safety and cycle performance of PVDF/TBAPF 6 /OMMT separator is improved. A tree-like structured gel nanofibrous membrane (TLNM) including lamellar organic montmorillonite (OMMT) is designed and prepared via one-step electrospinning method. And its application as promising separator for lithium-ion capacitor were systematically researched. Based on the special structure and the addition of lamellar OMMT, the TLNMs are endowed improved mechanical performance, excellent thermal stability and flame-retardant, and good electrochemical properties for Li ion capacitor (LIC). As a result, the nanofibrous membranes exhibits enhanced electrolyte uptake performance (~870%, with an electrolyte contact angel of 0°) and robust thermal dimensional stability (stable at 160°C for 1.5 h). Furthermore, the limiting oxygen index of this membrane is as high as ~30%, which can significatively improve the safety of the nanofiber separator. And the assembled Li ion capacitor with the membrane presented superior ion conductivity (3.95*10−3 S cm−1). Additionally, the LIC also shows enhanced cycling stability (~60% capacity retention after 10,000 cycles at 0.5C), and favorable rate capability. All of the results indicate that the novel polymer gel membrane including excellent flame retardancy and superior ion conductivity is expected to be used for high-performance lithium-ion capacitor. [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermally conductive, flame resistant, and mechanically robust nanocellulose composites was prepared. • BNNS was functionalized with ammonium polyphosphate (APP) by electrostatic assembly strategy. • Strong hydrogen-bonding interaction was formed between BNNS-p-APP with cellulose nanofibers (CNFs). • CNFs/BNNS-p-APP composites can improve the heat dissipation and fire safety of electronic products. Highly thermally conductive and flame resistant nanocellulose-based composites can synchronously achieve efficient thermal dissipation and low fire hazards of electronic devices, which shows great promise in next-generation green and flexible electronics. However, it has long been intractable to optimize the high thermal conductivity (TC) and flame resistance simultaneously. Herein, synergetic integration of high TC and flame resistance in nacre-like nanocellulose composites has been successfully achieved by the vacuum-assisted filtration of cellulose nanofibers (CNFs) and functionalized boron nitride nanosheets (BNNS-p-APP). Benefiting from the highly oriented hierarchical microstructure, strong hydrogen-bonding interaction, and successful immobilization of ammonium polyphosphate (APP), the as-obtained CNFs/BNNS-p-APP composite film achieves a high in-plane TC of 9.1 W m−1 K−1 and outstanding flame resistance. Meantime, this eco-friendly nanocellulose-based composite also exhibits remarkable flexibility, folding endurance, and mechanical robustness, robustness, which may open up a new opportunity for the thermal management of flexible electronics. [ABSTRACT FROM AUTHOR]

In lithium-ion batteries (LIBs), benefiting from various functional components, functional separators can possess different capabilities to cope with the risks in complex application scenarios. In this work, a functional separator based on the phosphonate-modified nano-scale silica ceramic particles is fabricated to reduce the safety risks in LIBs. Through an anhydrous polymerization process, dimethyl vinylphosphonate (DMVP), a kind of widely used flame retardants, is grafted on silica (SiO 2). Then the modified SiO 2 (mSiO 2) is coated on the pristine polyethylene separator by a typical coating process. Combining the function of the ceramic and phosphonate, the modified ceramic separator displays substantially enhanced thermal stability, without visual thermal shrink up to 200 °C. The flame resistances of separator itself and pouch cells are also significantly improved, even though flammable electrolyte is added. Different from the case when the phosphonate is used as an additive in electrolyte, the phosphonate is fixed firmly on the separator and not easy to be embedded in carbon anode after battery cycles. The coin cells assembled with the modified separators are away from the irreversible loss of discharge capacity and low Coulombic efficiency for the first cycle, which can be attributed to the firm immobilization of organic phosphonate. • Flame retardant phosphonate is fixed on silica ceramic by double bond polymerization. • Immobilized phosphonate will not be embedded in the graphite anode in battery cycles. • Phosphonate further enhances thermal stability of functional separator. • Accordingly, flame resistances of separator itself and cells are markedly improved. [ABSTRACT FROM AUTHOR]

• Hybrid PEG/GONR/MMT networks are constructed via a bio-inspired strategy. • The hybrid networks produce synergistic reinforcing and toughening efficiencies. • The nacre-like networks show excellent flame resistance and structural stability. • Efficient fire alarm responses (fire rapid detection and early warning) are obtained. Water-based hybrid graphene oxide nanoribbon (GONR)/montmorillonite (MMT)/polyethylene glycol (PEG) networks were prepared by using a facile bio-inspired low-temperature evaporation induced assembling process. Multiple non-covalent and covalent interactions together with a high orientation level of MMT were constructed in the hybrid PEG/MMT/GONR networks. As a result, the hybrid networks exhibit synergistic reinforcing and toughening efficiencies when compared with the composites modified with the single-phase filler, e.g. 152% and 167% increase in tensile strength for the optimized ternary composites in comparison with those of the binary composites. Moreover, the nacre-like hybrid networks show excellent flame resistance and structural stability in a flame due to the formation of interconnected and compact char after combustion, which can be applied as protective coatings to combustible materials. The hybrid coatings not only improve the flame-retardant property (e.g. ~46% decrease in heat release rate at 30 wt%) of the combustible PU foam materials significantly, but also provide ideal fire alarm responses (e.g. rapid flame detection of ~2 s and effective fire early warning signals in pre-combustion). Owing to the green and versatile synthesis scheme, excellent mechanical performance and flame resistance, these hybrid PEG/MMT/GONR networks are promising widespread application. [ABSTRACT FROM AUTHOR]

Taking into account numerous results from the literature, an in-depth exploratory study on the chemical gradients in the rise (or depth) direction was performed on polyisocyanurate rigid (PIR) foam insulation panels using ATR-FTIR spectroscopy. In particular, it was found that the isocyanurate/phenyl ratio is a quick and effective technique for providing an indication of the level of trimer conversion within each sample. More importantly, a detailed analysis of the C–N stretching vibration of the isocyanurate ring as a function of depth revealed a linear decrease in the frequency peak maximum with the increase in the isocyanurate ratio for all investigated PIR foams. This result suggests for the first time that the position (frequency) of peak maximum (C–N stretching of isocyanurate ring) may be used to quantify the extent of isocyanurate formation without the issues linked to the use of absorbances. It is proposed that this reduction in the frequency of the C–N stretching vibration of isocyanurate ring reflects the decrease in hydrogen bonding between N–H of urethane group and C O within the isocyanurate ring when the isocyanurate content increases (lower mobility associated with higher level of cross-linking). The heterogeneity of the isocyanurate content was physically confirmed by investigating the flammability of the foam samples taken at different positions in the rise direction (z-axis). • Strong isocyanurate gradients in polyisocyanurate foam panels in the surface vicinity. • Flammability test improvement with the increase in isocyanurate content. • Linear decrease of C–N peak maximum frequency with increase in isocyanurate content. • C–N peak maximum frequency applicable to quantify extent of isocyanurate conversion. • Downwards frequency shift may reflect the decrease of hydrogen bonding. [ABSTRACT FROM AUTHOR]

Because of containing urea groups, flame resistance and smoke releasing behaviors of isocyanate-based polyimide foam (IBPIF) produced using free foaming technology require further improvement. In this work, silica aerogel layers were incorporated into cells of IBPIF through an in situ growth process of silica sol (SS). Compared with silica aerogel particles directly mixed into the foaming slurry, the silica aerogel layers that firmly attached to the pores and surfaces of cells not only provided exceptional thermal insulation and flame protection, but also kept original cellular structure. With increase in ratio of SS mass to IBPIF volume, silica aerogel incorporation dosage was gradually increased. Accompanied by flame resistance was obviously improved and smoke releasing behavior was effectively suppressed. Those were indicated by the improved limiting oxygen index (LOI), decreased heat release rate (HRR), peak of HRR, and specific optical density of smoke (Ds) in trials with pilot flames. Compared with pure IBPIF, when the ratio reached to 5/15 g/cm3, it resulted in LOI increasing from 22.0% to 33.0%, peak of HRR, total smoke production (TSP), and maximum value of Ds decreasing from 174 to 72 kW/m2, 1.11 to 0.37 m2/m2, 45.90 to 17.45, respectively. • Layered silica aerogel with heat insulation and fire resistance could firmly attach to the pores and surfaces of IBPIF cells. • With increase in ratio of M(SS)/V(IBPIF), silica aerogel incorporation dosage was gradually increased. • By the situ sol-gel growth, the cell structure of IBPIF could not be changed even when silica aerogel was added to 131.8%. • As silica aerogel dosage and thickness added, IBPIF flame resistance was enhanced, and smoke release behavior was inhibited. • As M(SS)/V(IBPIF) was 5/15 g/cm3, IBPIF LOI value was 30%, smoke maximum specific optical density was reduced by 62%. [ABSTRACT FROM AUTHOR]

• Appropriate ZrP (1 wt%) enhances flame resistance with a reduced FGI of 0.32 kW m−2·s-1. • ZrP facilitates double-layer char residues depending on catalytic charring and decomposition. • ZrP makes the E α of 310∼370℃ climb from 187.85–210.79 kJ mol−1 by pyrolysis kinetics. The effect of zirconium phosphate (ZrP) on the fire resistance of aliphatic waterborne polyurethane (AWP)-based intumescent flame retardant coatings (IFRCs) has been preliminarily investigated by quantitative analysis including the cone calorimeter and pyrolysis kinetics of ZrP-containing AWP-based coating, respectively. It determines that an appropriate dosage (1 wt%) of ZrP in the AWP-based coating constitutes an improved fire resistance, evidenced by the fire growth index decreased from 0.49 to 0.32 kW m−2·s-1, and the risen fire performance index of 0.55 s m−2 kW-1 from 0.41 s m−2 kW-1. Because of the heat sink (Zr(HPO 4) 2 ⋅H 2 O→ZrP 2 O 7) and catalytic charring of ZrP, the ZrP-containing AWP-based coating exhibits an enhanced flame resistance, evidenced by the formation of double-layer char residues. Furthermore, it clarifies that the 3D Jander model (n=2) mainly governs the whole pyrolysis process of the coating by modified Coats-Redfern integral method, the doped ZrP mainly makes the E α of 310∼370 ℃ climb from 187.85 kJ mol-1 to 210.79 kJ mol-1, and the E α during 95∼200 °C increases from 24.96 kJ mol-1 for S0 to 42.63 kJ mol-1. It provides a quantitative analysis of the flame-retarding mechanism of organic-inorganic hybrid coatings firstly. [ABSTRACT FROM AUTHOR]

• Appropriate ATP (2 wt%) facilitates decrease of FGI from 0.49 to 0.34 kW m−2 s−1. • 3D Jander model (n = 2) mainly governs the whole pyrolysis of AWP-based coating. • ZrP contributes to the increased E α from 26.33 to 39.38 kJ mol−1 during 95–215 ℃. The effect of aluminum triphosphate (ATP) on the flame resistance of intumescent flame retardant coatings (IFRCs) has been explored, using the aliphatic waterborne polyurethane (AWP) as the binder, the quantitative analysis on the pyrolysis kinetics of ATP-containing AWP-based coating is investigated. It determines that an appropriate dosage (2 wt%) of ATP in the AWP-based coating exerts an enhanced flame resistance, evidenced by the fire growth index decreased from 0.49 to 0.34 kW m−2 s−1, and the shrunk heat release rate during the whole burning. Due to the heat sink, filling of Al(PO 3) 3 for reinforcing char residues, and the catalytic charring, the doped ATP contributes to the increased E α from 26.33 to 39.38 kJ mol−1 corresponding to the stage of 95–215 ℃, according to the fitting 3D Jander model, which mainly governs the whole pyrolysis process of coatings. It identifies a quantitative evaluation on the flame resistance of AWP-based IFRCs modified by inorganic ATP. [ABSTRACT FROM AUTHOR]

• GO-PA paper is prepared by an evaporation-induced self-assembly method. • Fire sensor based GO-PA exhibits ultrasensitive and durable warning response. • Enhancement in fire resistance of GO is attributed to in situ phosphorus doping. Although traditional fire detectors are widely used in many occasions, they still show some limitations, such as slow fire response and poor resistance to severe conditions. Thus, it is urgent to design and exploit early fire-warning device with ultrafast response and flame-retardant ability to provide timely and fast alarm. Herein, graphene oxide paper functionalized with phosphoric acid (GO-PA) is fabricated by a facile and environmentally friendly water evaporation-induced self-assembly approach. Based on the flame-induced electrical resistance transformation characteristic of GO-PA, a fire-warning detector is designed to reliably monitor early fire. Fire alarm can be triggered within 0.5 s when GO-PA samples are attacked by fire. The GO-PA composite paper is more sensitive than GO-based fire sensors reported in the literature. Phosphorus atoms are in situ doped into graphene structure during flame exposure. Combustion reaction of GO is significantly retarded by the incorporated PA, thus fire duration time of GO is greatly improved. This work paves a new way to improve fire detection performance of GO-based sensors. This work provides a guide for the development of advanced fire detection and early-warning sensors to provide reliable and continuous alarm signals. [ABSTRACT FROM AUTHOR]

Chlorinated nitrile rubber (Cl-NBR) has been blended with chlorinated ethylene propylene diene rubber (Cl-EPDM) in different ratios by a conventional mill mixing method. The effect of the blend ratio on processing characteristics, mechanical properties (such as tensile and tear strength, elongation at break, hardness, abrasion resistance, heat build-up and resilience), structure, morphology, glass transition temperature (T g), thermal stability, flame retardancy, oil resistance, AC conductivity, dielectric properties and transport behavior of petrol, diesel and kerosene were investigated. The shift in absorption bands of blends studied from FTIR spectra, single T g from DSC analysis and decrease in amorphous nature from XRD showed the molecular miscibility in Cl-NBR/Cl-EPDM blends. SEM images showed the uniform mixing of both Cl-NBR and Cl-EPDM in a 50/50 blend ratio. The TGA curves indicated the better thermal stability of the polymer blend. The elongation at break, heat build-up, resilience and hardness of the polymer blend decreases with an increase in Cl-NBR content in the blend whereas the flame and oil resistance were increased with increase in Cl-NBR content. Among the polymer blends, the maximum torque, tensile strength, tear and abrasion resistance was obtained for the 50/50 blend ratio because of the effective interfacial interactions between the blend components. AC conductivity and dielectric properties of polymer blend increased with increase in the ratio of Cl-NBR in the blend. Different transport properties such as diffusion, permeation and sorption coefficient were measured with respect to nature of solvent and different blend ratios. Temperature dependence of diffusion was used to estimate the activation parameters and the mechanism of transport found to be anomalous. • Novel Cl-NBR/Cl-EPDM blends were prepared by a simple two roll mixing. • Excellent enhancement in mechanical properties. • Single glass transition temperature confirms the miscibility of rubber blends. • Flame retardancy, thermal stability and oil resistance of the rubber blends were greatly enhanced. • Transport of petroleum solvents with Cl-NBR/Cl-EPDM blends were also evaluated. [ABSTRACT FROM AUTHOR]

• The multifunctional conductive ACF and AFWS were prepared by layered deposition. • The resulted ACF and AFWS possess great superamphiphobicity and flame retardancy. • The obtained ACF has a low surface resistance of 1.1 Ω/sq and stable conductivity. • The AFWS shows rapid detection response for flame and high temperature within 3 s. • The smart fabric is useful for wearable electronic textile and fire-warning device. Flexible wearable electronic textiles are in great demand with the rapid development of intelligent electronic clothing systems. Nonetheless, developing the wearable textiles-based all-weather conductive fabrics with high conductivity and sensitive temperature response property remains a huge challenge. Herein, an all-weather high conductive fabric (ACF) and fire warning sensor (AFWS) have been successfully fabricated on the basis of the multifunctional superamphiphobic cellulose fabric with high conductivity and excellent flame-retardant property. It is worth noting that the as-prepared ACF and AFWS have different surface resistances, which are 1.1 Ω/sq and 1 kΩ/sq, respectively. In comparison with the previously reported conductive textiles, the resulted ACF shows superior electrical stability even under extreme conditions such as complex water phase, oil phase, flame and bending. Moreover, the LED array has been designed and exhibits good electrical properties by virtue of the high conductivity and favorable oil-water repellency of the ACF, demonstrating wide application prospects in large-scale preparation of wearable electronic textiles. In addition, the as-prepared AFWS exhibits sensible temperature-responsive electrical resistance change, which can quickly respond within 3 s. More importantly, the mechanism of rapid reconstruction of the conductive network on the functionalized fabric surface driven by phosphorus blowing agent at high temperature have been well proposed. The current work provides a new idea to develop advanced multifunctional all-weather wearable electronic device, which can effectively realize real-time monitoring of human health and early warning of abnormal high temperature in various harsh outdoor environments. [ABSTRACT FROM AUTHOR]

The development of high-performance biomass-derived epoxy thermosets with excellent flame resistance is vital to various applications (i.e., composites, coatings and adhesives). Herein, a difunctional epoxy monomer bis(2-methoxy-4-(oxiran-2-ylmethyl)phenyl) phenyl phosphate (BEU-EP) was synthesized from abundant and biobased eugenol. In addition, BEU-EP was cured by 4,4′-diaminodiphenyl methane (DDM) and the cured resin diglycidyl ether of bisphenol A (DGEBA)/DDM was used as a reference. Results indicated that BEU-EP/DDM not only showed a 58.1%, 28.8% and 35.1% increase in residual char (at 700 °C), flexural and storage modulus (at 30 °C) compared with DGEBA/DDM, but also exhibited excellent flame resistance and smoke suppression. BEU-EP/DDM passed V-0 rating (in UL-94 testing) with limiting oxygen index (LOI) of 38.4% and greatly decreased the peak heat release rate (pHRR) and total smoke production (TSP) by 84.9% and 80.5%, respectively. The mechanism analysis confirmed that the phosphorus-containing group and aromatic structure from BEU-EP contributed both the gas and condensed-phase flame retardation of BEU-EP/DDM network. This work provides an efficient and scalable route for synthesizing biobased epoxy thermosets with high integrated performance and superior flame resistance. Image 1 • A biomass-derived epoxy thermoset was synthesized from phosphorus-containing compound. • Phosphorus-containing structure promotes char formation and reduces the fire hazards of epoxy thermoset. • The new epoxy thermoset exhibits superior mechanical properties and high smoke suppression. • This paper provides a new strategy for enhancing the fire resistance of bio-based epoxy thermoset. [ABSTRACT FROM AUTHOR]

• Silane and LAA co-crosslinked GO network was prepared via a facile strategy. • The hybrid GO network shows good structure stability and improved flame retardancy. • LAA promotes thermal reduction of GO, thus providing efficient fire alarm response. • Flame-retardant mechanisms and fire alarm behaviors were discussed and clarified. Frequent fire disasters have not only caused massive casualties, irreparable property and priceless artefacts loss, but also create severe environmental damage. Therefore, it is imperative, but also challenging, to obtain excellent fire resistance and efficient early-warning alarm response in precombustion of combustible materials. In this work, a green flame-retardant graphene oxide (GO) based paper/coating is designed and constructed via using a facile 3-methacryloxypropyltrimethoxysilane and L-ascorbic acid (LAA) co-functionalization strategy. The optimized co-modified GO network shows good structure stability and improves the flame retardancy of combustible materials. Further, such GO network can provide an ultrafast flame detection signal of only ~1 s and ideal fire early warning responses (e.g. a low responsive temperature of ~120 °C and an extremely rapid responsive time of ~7 s at 300 °C) in precombustion which are among the best performances of the state-of-the-art fire alarm sensors. Moreover, the transformation of silane molecules into a compact protective layer on sheets and the resistance transition of insulating GO network into conductive reduced GO path promoted by LAA molecules are clarified. This work provides a novel strategy and paradigm to achieving excellent flame resistance and ideal fire early warning response of GO network for fire safety and prevention applications. [ABSTRACT FROM AUTHOR]

• PVDF/TPP/CA composite membranes are prepared by one-step electrospinning. • PVDF/TPP/CA composite membranes show flame resistance properties. • PVDF/TPP/CA membranes have improved electrolyte wettability and thermal stability. • PVDF/TPP/CA-based batteries have high capacities and better rate performances. Current developments of lithium-ion batteries (LIBs) are mainly focused on improving security and cycle performance. Herein, a novel polyvinylidene fluoride (PVDF)/triphenyl phosphate (TPP)/cellulose acetate (CA) nanofiber membrane was fabricated by one-step electrospinning and used as separator in lithium-ion batteries. Compared to traditional polyethylene membrane, the obtained composite showed higher porosity, elevated thermal stability, superior electrolyte wettability, and improved flame resistance. In addition, batteries assembled with PVDF/TPP/CA membrane exhibited excellent electrochemical properties and cycle stability. The enhanced performances were attributed to the porous structure and presence of CA and TPP. Overall, the proposed hybrid organic cellulose-based composite polymer membranes look promising as separators for advanced LIBs. [ABSTRACT FROM AUTHOR]

A comparative investigation on the flame resistance and microstructure of graphite modified coatings is preliminarily investigated, which contains expanded graphite (EG d) and various expandable graphite (EG e). The increased peak heat release rate (p-HRR) from 83 to 123 kW m−2 for the 5 wt% EG d -containing sample reveals an obvious antagonistic effect, due to the poor adhesion between EG d and geopolymeric coating. However, the remarkably synergistic flame-retarding effect is identified between geopolymeric coating and the EG e with an expansion rate of 425 mL g−1, evidenced by the reduced fire growth index and p-HRR, the former drops from 0.25 to 0.17 kW m−2 s−1, and the latter decreases from 83 to 76 kW m−2 in comparison to that of barely geopolymeric coating. Due to the condensation of Q4 1 or Q4 2 siliceous groups during firing from results of 29Si magic angle spinning nuclear magnetic resonance, the EG e doped coating facilitates the formed shielding with voluminously lamellar structure. It clarifies the interactions between graphite and geopolymer coating including "barrier effect", "candlewick effect", "labyrinth effect", and "popcorn effect", preliminarily illustrating the flame-retarding mechanism. Image 1 • EG d exhibits antagonistic flame-retarding effect. • High expansion-rate EG e exerts synergistic flame-retarding effect. • Q4 1 and Q4 2 silica groups facilitate a continuous shielding layer. [ABSTRACT FROM AUTHOR]

• Modified fluororubber-based quasi-solid-state electrolytes were developed. • As-prepared QPE exhibits improved adhesiveness and flame-retarding ability. • The flexible SC based on as-prepared QPE shows excellent electrochemical performance. The poly(vinylidene fluoride- co -hexafluoropropylene) rubber (FKM) is a perfect matrix of organic quasi-solid-state polymer electrolyte (o QPE) due to its outstanding chemical stability, excellent elasticity, and non-flammability. However, the poor adhesion to electrodes limits its practical application. Herein, the porous FKM grafted poly(butyl acrylate) membranes (p FKM-g-PBA), prepared through a template pore-forming and γ-ray radiation grafting method, is reported. The corresponding o QPE (p FKM- g -PBA/Et 4 NBF 4 -AN) shows superior stretchability (the retention of 96.3% after 1000 stretching cycles at 100% strain), high ionic conductivity (8.1 × 10−3 S cm−1), and good flame resistance. Benefit from the considerable increase in adhesiveness, the p FKM- g -PBA/Et 4 NBF 4 -AN o QPE adhere firmly to the carboxylated multiwall carbon nanotubes-supported poly(1,5-diaminoanthraquinone) (c MWCNT@PDAA) flexible electrodes. The as-assembled flexible supercapacitor (c MWCNT@PDAA// p FKM- g -PBA/Et 4 NBF 4 -AN// c MWCNT@PDAA) delivers a high energy density of 65.2 Wh kg−1 at a power density of 0.67 kW kg−1 and retains specific capacitance of 87% after 10,000 charge-discharge cycles which is better than that of the raw FKM-based device (75%). [ABSTRACT FROM AUTHOR]