•Tannin based flame retardancy occupying a major field in the field of sustainable flame retardancy of polymeric materials.•Tannin based polyphenols of different wastage plant extracts responsible ...for flame retardancy of natural and synthetic polymers.•Mechanism of flame retardancy exhibited condensed phase behavior of flame retardant action.•Thermo-gravimetric behavior of tannin treated polymers showed catalyzation of pyrolysis and high char retention.
Sustainable flame retardancy of polymeric materials is one of the thirsty, promising and challenging areas in today's fire safety world. Different researchers are trying to achieve that scientific beauty employing different research perspectives. Bio-based (bio-macromolecule) flame retardancy is one of the emerging and promising fields and continuously adding feathers in the crown of sustainable flame retardancy from the past decade. Bio-based flame retardants are sustainable. Tannin is an aromatic polyphenolic compound, one of the important and major active ingredients of most of the plant-based bio-macromolecules. As per reported documents, past few years have witnessed great flame retardancy potential of tannin and tannin based plant bio-macromolecules on textile, steel and other natural and synthetic polymeric materials. However, till date, no critical review has been registered on the compilation of the flame retardant performance of tannin and tannin based plant bio-macromolecule treated natural and synthetic textiles, polymeric substrates etc, This review report critically elucidates the thermal properties of tannic acid and in detail flame retardant performances of tannic acid (hydrolyzed and condensed), chemically modified tannic acid-treated textile, polymeric substrates. Besides, the review context also registers the mechanism involved behind the tannin based flame retardancy of different natural and synthetic polymeric substrates like cotton, wool, silk, epoxy resin, steel, polyester, nylon etc. Besides, some futuristic scientific suggestions and challenges also have been systematically discussed at the end part of this review manuscript.
A unique hybridized antioxidant named TiO2-KH550-PA, of which silane modified nano-TiO2 particles were grafted with 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid by acylation reaction, was ...applied to intumescent fire-retardant coatings for cable. Through fire protection test, contact angle test, thermogravimetric test and UV-ageing test, the effects of TiO2-KH550-PA on hydrophobicity, flame retardancy, smoke suppression, anti-ageing and charring performance for coatings were evaluated. The obtained results indicate that the TiO2-KH550-PA can enhance the hydrophobicity of the coating, thereby reducing the adhesion of dust on the coating surface. Additionally, TiO2-KH550-PA has a greatly promoting role in strengthening the fire protection abilities of the coating, but an appropriate amount is the key. Compared to coatings without composite, the intumescent fire-resistant coating for cable containing 1 wt% TiO2-KH550-PA (IFRCC2) exhibits excellent fire protection performance, including a prolongation by 2.6 times in failure time, an increase by 1.7 times in char layer height, and an increase by 0.4 times in light transmittance for smoke density test. Furthermore, the presence of TiO2-KH550-PA can also strengthen the oxidation resistance, charring ability and char layer stability of the coating, when the remaining mass of IFRCC2 increases to 49.0 % at 800 °C. The anti-ageing performance test demonstrates that the TiO2-KH550-PA can absorb ultraviolet light, eliminate free radicals, and raise the structural stability of the coating, thus reinforcing the durability of the fire resistance for the coating.
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•A unique hybridized antioxidant (TiO2-KH550-PA) was prepared.•The TiO2-KH550-PA can improve the hydrophobicity of the coating for cable.•The TiO2-KH550-PA enhances fire-retardant and UV-shielding behavior of the coating.•The flame-retardant mechanism of the coating containing TiO2-KH550-PA is proposed.
MXene aerogels have shown great potential for many important functional applications, in particular electromagnetic interference (EMI) shielding. However, it has been a grand challenge to create ...mechanically hyperelastic, air‐stable, and durable MXene aerogels for enabling effective EMI protection at low concentrations due to the difficulties in achieving tailorable porous structures, excellent mechanical elasticity, and desired antioxidation capabilities of MXene in air. Here, a facile strategy for fabricating MXene composite aerogels by co‐assembling MXene and cellulose nanofibers during freeze‐drying followed by surface encapsulation with fire‐retardant thermoplastic polyurethane (TPU) is reported. Because of the maximum utilization of pore structures of MXene, and conductive loss enhanced by multiple internal reflections, as‐prepared aerogel with 3.14 wt% of MXene exhibits an exceptionally high EMI shielding effectiveness of 93.5 dB, and an ultra‐high MXene utilization efficiency of 2977.71 dB g g−1, tripling the values in previous works. Owing to the presence of multiple hydrogen bonding and the TPU elastomer, the aerogel exhibits a hyperelastic feature with additional strength, excellent stability, superior durability, and high fire safety. This study provides a facile strategy for creating multifunctional aerogels with great potential for applications in EMI protection, wearable devices, thermal management, pressure sensing, and intelligent fire monitoring.
Hyperelastic, robust, fire‐safe multifunctional MXene aerogels with superior electromagnetic interference (EMI) shielding, thermal insulation, and air/moisture resistance are created by an encapsulation strategy. The MXene aerogel shows high EMI shielding effectiveness of 93.5 dB and ultra‐high EMI utilization efficiency of MXene of 2977.71 dB g g−1, resulting from efficient utilization of pore structure and multiple internal reflections.
This article discusses one of the methods of fire protection, namely, the coating of metal structures with fire retardant paints. Intumescent coatings are currently the most widely used. Fire ...retardant coatings based on epoxy paints have high performance characteristics and are promising. As the foaming component, the system of ammonium polyphosphate - pentaerythritol - melamine (in a ratio of 2: 1: 1) was selected. The fire retardant properties of the developed material were investigated. Coatings on the base of the developed fire retardant paint allow us to increase own level of fire resistance of metal constructions up to three (90 minutes).
Fire-retardant coatings have demonstrated effective fire protection for various materials, ranging from flammable polymeric foam and wood to nonflammable steel. However, the poor cost effectiveness ...has significantly impeded their real-world applications. In nature, lava is a flowing, noncombustible molten liquid with a low thermal conductivity. We, herein, report a lava-inspired micro/nano-structured ceramifiable organic-inorganic hybrid coating comprising low-melting glass powders (GPs), such as ceramic precursors; boron nitride (BN) nanosheets as synergists; and a fire-retardant polymer as a coating base. Upon exposure to flame, the coating forms a lava-like noncombustible ceramic char layer that can serve as a robust fire shield for underlying substrates. The hybrid coating-treated polyurethane foam exhibits a rapid self-extinguishing behavior and increased compressive strength, outperforming its previous counterparts. Meanwhile, the hybrid coating offers exceptional fire protection for solid wood and steel. This work provides a bioinspired strategy for creating cost-effective fire-retardant coatings for diverse industrial applications and a fire-safe world.
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•Lava-inspired fire-retardant coatings form a ceramic layer upon exposure to flame•A 200-μm-thick hybrid coating enables rigid PU foam to self-extinguish instantly•Coated PU foam shows increased mechanical strength and retained thermal insulation•The hybrid coating offers desired fire protection for solid wood and steel sheets
Globally, frequent building fires have raised an urgent demand for fire-safe building materials. A promising solution to this concern is to engineer fire-retardant coatings. Existing fire-retardant coatings, however, are usually inefficient, costly, difficult to mass produce, and adhere poorly to substrates, which significantly impedes their real-world applications. Herein, we report a lava-inspired effective but inexpensive ceramifiable organic-inorganic hybrid fire-retardant coating, which, upon exposure to flame, can yield an integral noncombustible ceramic protective layer as a robust fire shield for underlying substrates. This fire-retardant coating exhibits desired fire protection for a variety of building materials, including polymer foam, solid wood, and steel sheets. This design principle enables the creation of next-generation cost-effective fire-retardant technologies and fire-safe buildings.
A lava-inspired ceramifiable organic-inorganic hybrid fire-retardant coating has been rationally designed. This fire-extinguishing coating has demonstrated an extraordinary fire protection capability for many building materials because of its ability to form a noncombustible protective layer that can serve as a robust fire shield for underlying substrates. This strategy affords a promising cost-effective fire-retardant technology, which ultimately enables a fire-safe living environment and the protection of life and property.
The article discusses the actual problems of the formation of future teachers’ digital competencies, which are an important aspect of professional success. The positive aspects of education ...digitalization are shown. The task of improving the process of developing digital competencies of future teachers studying in the profiles of Life Safety and Physical Education is being solved. The formation of future teachers’ digital competencies of the life safety basics is considered from the standpoint of a metasubject approach. It is shown that the formation of digital competencies of future life safety teachers is a process of purposeful pedagogical influence on a student in order to develop a set of skills, abilities and knowledge that allows using digital technologies effectively to solve professional problems at all levels of education. The conditions for the formation of digital competencies are determined. The formation of the components of digital competence among practicing teachers of life safety is considered. It is shown that the formation of digital competencies of future life safety teachers is possible implementing specialized disciplines, educational and industrial practices that include the organization of pedagogical activities in a digital environment from the standpoint of health preservation, creating a comfortable educational environment.
Highlights
The
p
–
n
segment thermoelectric aerogel fiber was fabricated through an alternating coaxial wet-spinning strategy.
Resultant alternating
p
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segment thermoelectric fiber was ...electrically connected in series (two
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pairs with a length of 3 cm) with an outstanding electrical conductivity of 23.76 S m
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Thermoelectric textile-based self-powered fire warning electronics exhibited sensitivity (trigger time within 1.43 s) and repeatable temperature sensing performance for firefighting clothing.
Firefighting protective clothing is a crucial protective equipment for firefighters to minimize skin burn and ensure safety firefighting operation and rescue mission. A recent increasing concern is to develop self-powered fire warning materials that can be incorporated into the firefighting clothing to achieve active fire protection for firefighters before the protective clothing catches fire on fireground. However, it is still a challenge to facilely design and manufacture thermoelectric (TE) textile (TET)-based fire warning electronics with dynamic surface conformability and breathability. Here, we develop an alternate coaxial wet-spinning strategy to continuously produce alternating
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/
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-type TE aerogel fibers involving
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-type Ti
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C
2
T
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MXene and
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-type MXene/SWCNT-COOH as core materials, and tough aramid nanofiber as protective shell, which simultaneously ensure the flexibility and high-efficiency TE power generation. With such alternating
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/
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-type TE fibers, TET-based self-powered fire warning sensors with high mechanical stability and wearability are successfully fabricated through stitching the alternating
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segment TE fibers into aramid fabric. The results indicate that TET-based fire warning electronics containing 50
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n
pairs produce the open-circuit voltage of 7.5 mV with a power density of 119.79 nW cm
−2
at a temperature difference of 300 °C. The output voltage signal is then calculated as corresponding surface temperature of firefighting clothing based on a linear relationship between TE voltage and temperature. The fire alarm response time and flame-retardant properties are further displayed. Such self-powered fire warning electronics are true textiles that offer breathability and compatibility with body movement, demonstrating their potential application in firefighting clothing.
•The multifunctional transparent fire-retardant coating reinforced with talc was fabricated.•Excellent fire protection, smoke suppression and adhesion properties were obtained.•Uniform dispersion of ...talc imparted indeed transparency in the range of 84.5%-88.9%.•Antibacterial rate against E. coli bacteria reached 99.0% after introducing talc.•Remarkable enhancement on ageing resistance was achieved by adding talc.
To enhance the fire safety of historic buildings, developing fire-retardant coatings with integrated decoration, fire protection, ageing resistance and antibacterial performances is imperative. Here, a novel multifunctional transparent fire-retardant coating with fire protection, smoke suppression, antibacterial and anti-ageing functions was successfully fabricated using talc as a multifunctional synergist. Mechanical tests show that the multifunctional coating containing talc shows an improvement in pencil hardness and adhesion classification while keeping a high transparency. Moreover, adding talc is conductive to fabricate a physical barrier with super compactness and intumescence, which endows the coatings with excellent fire protection and smoke suppression functions. Especially, when the mass ratio of PPB to talc is 95:5, the obtained MTPPB3 coating retains a high-level transparency of 85.8%, accompanying with a 72.6% reduction in flame spread rating and a 57.0% reduction in smoke density rating compared to MTPPB0 without talc. TG analysis shows that the multifunctional coatings containing talc exhibit sharp enhancements in thermal stability and char yield, and MTPPB3 retains 32.7% residue at 800 °C. Meanwhile, the addition of talc results in high antibacterial rate against E. coli bacteria and durable flame-retardant and smoke suppression effects, and MTPPB3 shows an antibacterial rate of 99.0% against E. coli bacteria. This work provides a promising way to fabricate multifunctional transparent fire-retarded coatings with outstanding functions of decoration and fire protection.
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•Computational framework for the assessment of the fire resilience is proposed.•Multi-layer zone model is used for evaluating hazard in a fire environment.•Recovery time of a fire-affected building ...is estimated using statistical correlations.•Response in an early stage of a fire is important to enhance the fire resilience.
Fire resilience is a measure that quantifies functional continuity of a building damaged by a fire. Despite its numerous advantages, only a few studies have attempted to assess fire resilience. In this study, a computational framework using the multi-layer zone model was developed for assessing the fire resilience of buildings. The multi-layer zone model is an advanced form of the classical one-layer and two-layer zone models; the model divides rooms of analysis into multiple horizontal control volumes, called zones, for the governing equations of the fire induced environment behavior. This model is suitable for evaluating damage of building components in the fully developed stage of a fire with almost uniform temperature distribution inside the rooms and in the earlier stages with vertically stratified temperature distributions. This is an important feature of fire hazard evaluation because a small rise in temperature or dispersion of smoke can cause damage to certain types of building components, such as non-structural members, equipment systems, and stored items with relatively low fire resistivity. All the components should remain undamaged for the functional continuity of buildings. The framework assesses the damage ratio of a building by aggregating the building components of each zone that is calculated using vulnerability functions. Based on recent statistics on fire incidents and building refurbishment in Japan, the damage ratio is further converted to recovery cost and time required for calculating the fire resilience. Hazard mitigating functions of fire protection equipment systems, i.e., fire extinguisher, indoor fire hydrant, sprinkler system, mechanical smoke exhaust system, and fire alarm system, were incorporated in the framework considering occupants’ response to a fire. As a case study, the fire resilience of a five-story office building was assessed using the Monte Carlo approach, where uncertain parameters associated with the fire source, fire protection equipment systems, occupants, and fire service were considered as variables. As a result, although a building component with relatively high fire resistivity (i.e., structural members) is a major factor influencing the cost and time required for recovery, extinguishment in the early stage of a fire was particularly important to improve the fire resilience of buildings. In this study, the damage ratios of building components were evaluated by the multi-layer zone model; the proposed framework provides an overview of the computational procedure for assessing the fire resilience of buildings, which can be a guide for the other types of fire hazard models.
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•Graphene considered as a promising carbon nanomaterials with unique properties.•Graphene and their composites present new generation of flame retardant materials.•Graphene sheets ...have effective ability to form protective char layer as flame retardants.•Graphene sheets have superior flame retardancy effect than clay and CNTs.•Graphene sheets present renewable smart generation of flame retardant materials.
Polymeric and textile based materials constitute the majority of market products, however, due to their low thermal stability and high flammability hazards, their uses are limited in some applications. Therefore, flame retardant materials have to be dispersed as fillers in polymer matrix and coated on textile fabrics to enhance their fire safety and thermal stability. Graphene is two-dimensional materials and considered as a promising carbon nanomaterials with sp2-hybridization and with unique properties. In this review article conventional flame retardant and different methods of synthesis of graphene layers were summarized. Also, the possibility of use graphene sheets alone as flame retardant material for polymeric materials was reviewed and compared with other common nanofillers. Graphene sheets and their composite as flame retardant nanofillers for polymers and flame retardant coating for textiles are discussed in details. Synergistic flame retardant effect of use of nanoparticles decorated graphene sheets as flame retardant for polymer nanocomposites are discussed.
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