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High safety and stability in batteries are crucial factors for the large‐scale application of lithium‐ion technology. In this work, flame‐retardant aluminum diethylphosphonite (ADP) is coated by urea‐formaldehyde (UF) shell to conquer the side reactions caused by ADP during cycling process. And then the core@shell structured ADP@UF is combined with poly(ethylene oxide) (PEO), high thermal stability can be realized. When exposed to high temperatures, ADP@UF generates N⋅ and P⋅ radicals to eliminate the combustion the H⋅ and OH⋅ radical, to inhibit fire. By controlling the percentage of flame retardant added, PEO‐ADP@UF has totally achieved the effect of inflaming retarding, realizing stable electrochemical properties at the same time. The −NH2 in UF forms hydrogen bonds with PEO, and acts as a Lewis base to promote the dissociation of lithium salts to increase the lithium‐ion mobility number. Compared to PEO, battery with PEO‐ADP@UF has outstanding cycling performance (103 mAh g−1 at 1 C, 2.5–4.2 V) and long service life (800 cycles). [ABSTRACT FROM AUTHOR]

In order to improve the flame retardancy of EPS insulation materials, different volume ratios of magnesium oxychloride cement (MOC) were added to EPS and its properties were studied. The results show that the mechanical properties of EPS insulation materials gradually increase with the increase of MOC volume ratio. As the volume ratio of MOC increases, the dry density and thermal conductivity of EPS insulation materials continue to increase, indicating a continuous decrease in insulation performance. The limited oxygen index (LOI) of pure EPS is only 18.1%. As the MOC volume ratio increases, the LOI of EPS insulation material gradually increases and combustion becomes more difficult, significantly improving its flame retardancy. When the MOC volume ratio is 9%, EPS insulation material can self extinguish in a short period of time. As the volume ratio of MOC increases, the combustion performance level of EPS insulation materials gradually increases from flammable B3 level to non flammable A2 level. Based on the requirements for the performance of EPS insulation materials in JG/T 536--2017, when the volume ratio of MOC is 9%, the comprehensive performance of EPS insulation materials is optimal. At this time, the compressive strength and tensile strength of EPS insulation materials are 0.256 MPa and 0.198 MPa, respectively, with a dry density of 149 kg/m³, a thermal conductivity of 0.055 3 W/(m·K), and a flame retardant grade of A2. [ABSTRACT FROM AUTHOR]

Graphite oxide (GO) was used to modify polycarbonate (PC) to prepare flame retardant PC composites and the effects of GO content on the flame retardancy, mechanical properties, and heat resistance of composites. The results showed that the flame retardancy and heat resistance of composites increased with the increase of GO content, and the tensile strength, bending strength, and impact strength of the composites continued to increase, while the elongation at break gradually decreased. When the GO content is 3%, the composites with good flame retardancy, mechanical properties, and heat resistance can be obtained. At this time, the limited oxygen index (LOI) of the composites reaches 32.8%, the flame retardancy level reaches V-0, and the total heat release (THR) and total smoke production(TSP) are reduced by 45.8% and 75.7%, respectively. Compared with pure PC, the tensile strength, bending strength, and impact strength are increased by 25.4%, 33.7%, and 63.2%, respectively, the elongation at break is reduced by 7.1%. The temperature at which the weight loss is 5% is increased by 19 °C, the peak temperature of thermal weight loss is increased by 52 °C, and the mass residual rate of thermal decomposition is increased by 8.9%. [ABSTRACT FROM AUTHOR]

Sandwich composite is an important part of engineering products capable of replacing metallic composite. It consists of two types of material, namely polypropylene honeycomb core and skin made from jute fiber-reinforced epoxy composite (JFRP), which are joined with glue. This study presented a unique discussion about adhesives that focused on the burning rate and emission performance of SA-A and SD-E. The burning rate performance was assessed with the UL-94 HB test in accordance with the ASTM D 635 standard. Emission value of both adhesives was also examined in line with the ASTM D 2863 standard using a Gasboard-3100P Syngas analyzer. In addition, FTIR and SEM analyses were used to determine the characteristics of the SA-A and SD-E adhesives. The results showed a significant difference in adhesives rates, with SA-A burning 0.5% faster than SD-E in addition to a 0.58% reduced weight loss. Emission test confirmed that both adhesives have similar LOI values of 22.6% and 22.8%, respectively. SA-A adhesives contained LSD, which is dangerous to human health. In conclusion, SD-E adhesives should be used on sandwich composite due to its epoxybased potential as a flame retardant because SA-A adhesives has more potential to trigger firing due to the fuel content. [ABSTRACT FROM AUTHOR]

Flexible polyurethane foam (FPUF) has a widespread application across aerospace, furniture and vehicles, while its flammability always arouses severe safety concerns. Herein, a novel, bio-based flame retardant, i.e. polyol (PADEA) that contains phosphorus and nitrogen elements, was successfully synthesized by using phytic acid (a bio-organic acid) and diethanolamine as crude materials. Then, PADEA partially substituted the commercial polyether polyols in the foaming process, during which PADEA reacted in situ with isocyanate to construct an inherently flame-retardant FPUF. Due to the purposive designed P-N synergistic molecular structure, PADEA can serve as a highly efficient intumescent flame-retardant (IFR) system. When 40 php (ca. 21.51wt%) PADEA was added into the system, the limiting oxygen index (LOI) of the obtained FPUF reached up to 24.1%, achieving a 22.0% increase compared to that of primitive FPUF without PADEA. Moreover, the addition of PADEA can considerably reduce the total number of melt drips in the UL-94 HB rating test. And the cone calorimeter (CC) results demonstrated a 47.08% reduction in total heat release (THR) was achieved as 40 php PADEA was added. At the end, various characterization methods were carried out, revealing the flame-retardant mechanism of PADEA both in condense and gaseous phase. This work highlights a facile and green strategy for designing functional polyol to address the flame-retardant issues of high-performance FPUF. [ABSTRACT FROM AUTHOR]

This study aims to investigate the flame retardancy and mechanical properties of polypropylene (PP)‐based intumescent flame retardants (IFRs) consisting of melamine phosphate (MP) and pentaerythritol (PER), and different additives; boron phosphate (BP), antimony oxide (AO), and preceramic polymers, namely poly(dimethylsilane) (PDMS) and poly(methylsilsesquioxane) (PMSQ). The composites were produced by twin‐screw extrusion, and then molded by injection molding. Their characterizations were performed with limiting oxygen index (LOI), horizontal burning tests, thermogravimetric analysis (TGA), tensile and impact tests. The total amount of IFRs and the additives in polypropylene was kept constant at 20 wt%. The additive concentration was varied as 1, 3, and 5 wt% in the composites. The highest LOI value of 29% was obtained for PP/MP/PER composite with MP/PER ratio of 3/1. PP/IFR‐based composites with 1 wt% additive exhibited higher LOI and horizontal burning performance than the other composites with 3 and 5 wt% additives. It is revealed that tensile modulus and impact strength of neat PP were improved with the addition of IFRs, and for each type and amount of the additives used in the study. Highlights: Usage of IFRs, preceramic polymers, BP and AO in PP improved flame retardancy.Lower amount of additives (1%) in PP/IFR composites led to higher LOI values.Additive incorporation enhanced tensile modulus and impact strength of neat PP. [ABSTRACT FROM AUTHOR]

The recycled nylon (RN)‐based biocomposites were fabricated by adding 25% lignin biocarbon. Lignin was pyrolyzed at 300, 600, and 900°C to produce Lig300, Lig600, and Lig900 biocarbon (BioC) samples, respectively. Higher functionality of Lig600 (unlike Lig900) allowed for improved interfacial interaction with the polar nylon matrix. Mechanical properties were further enhanced for RN_Lig600 composite with enhanced flexural and tensile strength by 18% and 8%, respectively, compared to neat polymer (RN). RN_Lig900 composite showed enhancement in tensile and flexural modulus by 32.6% and 51.1%, respectively, compared to RN. Incorporation of Lig900 in RN matrix resulted in 77.9% reduction in burning rate compared to RN. These results show the potential of lignin BioC as a filler in RN composites for flame retardant applications and mechanical enhancement, such as in the automotive industry. Highlights: Effect of pyrolysis temperatures (300, 600, and 900°C) on lignin biomass.Composites prepared from recycled polyamide 6 from carpet waste and biocarbon.Improved interfacial adhesion of 600°C biocarbon with recycled nylon matrix.Enhanced thermal, mechanical properties, reduced flammability of biocomposites.Sustainable biocomposites with 900°C biocarbon reduced burning rate by 78%. [ABSTRACT FROM AUTHOR]

In order to explore the influence of sugar treatment on the enrichment of γ-aminobutyric acid (GABA) in peanut sprouts, this paper selected the optimal application concentration of different types of exogenous sugars (mannose, sucrose and glucose). The effects of GABA on the germination of peanut seeds and the related substances of GABA anabolic metabolism were investigated and the possible mechanism of action was studied. The results showed that mannose, sucrose and glucose treatment could significantly (P<0.05) increase the content of GABA in peanut sprouts, and the activity of glutamate decarboxylase (GAD), diamine oxidase (DAO), polyamine oxidase (PAO) and the contents of glutamic acid, putrescine, spermidine and spermidine were significantly changed in oxidase (P<0.05). At the same time, according to the test results, different exogenous sugar treatments could increase the contents of ascorbic acid, protein and resveratrol in peanut sprouts to different degrees. GABA in peanut sprouts can be enriched by exogenous sugar treatment, and its influence mechanism may be GABA branch and polyamine degradation pathway. [ABSTRACT FROM AUTHOR]

Triphenyl phosphate (TPhP) is an organophosphate flame retardant and plasticizer that is added to a wide variety of consumer and industrial products. It is also a ubiquitous environmental pollutant. Exposure to TPhP has been shown to alter gene expression in metabolic and estrogenic signaling pathways in in vitro and in vivo models of a variety of species, and as such, is considered to be an endocrine disrupting chemical. Exposure to endocrine disrupting chemicals is increasingly being associated with changes to the epigenome, especially during embryonic development. The aim of this study was to evaluate whether TPhP exposure in aquatic ecosystems has the ability to alter the epigenome in two immortal cell lines derived from trout (Oncorhynchus mykiss). This study assessed whether 24 h exposure to TPhP resulted in changes to histone modification and DNA methylation profiles in steelhead trout embryonic cells and rainbow trout gill epithelial cells. Results show that several epigenetic modifications on histone H3 and DNA methylation are altered in the embryonic cells following TPhP exposure, but not in the gill epithelial cells. Specifically, histone H3 acetylation, histone H3 mono‐methylation and global DNA methylation were found to be reduced. The alterations of these epigenetic modification profiles in the embryonic cells suggest that exposure to TPhP during fetal development may alter gene expression in the developing embryo, likely in metabolic and estrogenic pathways. The impacts to the epigenome determined in this study may even carry multigenerational detrimental effects on human and ecosystem health, which requires further investigation. Triphenyl phosphate (TPhP) is an organophosphate flame retardant, ubiquitous environmental pollutant and endocrine disrupting chemical. This study evaluated whether TPhP exposure caused changes to posttranslational histone modifications and DNA methylation profiles in steelhead trout embryonic cells and rainbow trout gill epithelial cells. Histone H3 acetylation, histone H3 mono‐methylation and global DNA methylation were reduced in TPhP‐exposed embryonic cells but not gill epithelial cells. Results suggest that exposure to TPhP during fetal development may alter gene expression in the developing embryo. [ABSTRACT FROM AUTHOR]

Inflammable building finishing materials act as a major cause of fire propagation, and they, therefore, pose significant risks to life and can lead to property damage. To replace such flammable building finishing materials, many countries have established regulations limiting their use, which has led to extensive research on the development of flame-retardant building finishing materials. Such methods have included adding flame retardants to construction materials to reduce the heat release rate and total heat release. The present study aimed to enhance the fire performance of cellulose-based architectural finishing materials by creating a dual flame-retardant mixture using expandable graphite and magnesium hydroxide added to recycled paper waste. Specimen fabrication involves using a pressing method to apply uniform pressure to compress the mixture in a mold. The total heat release (THR), CO, and CO2 production of the produced specimens were measured using a cone calorimeter while varying the magnesium hydroxide additive ratio. The combustion gases were measured through NES 713 experiments to determine any changes in the Toxic Index corresponding to variations in the magnesium hydroxide content. The experiment results established a correlation between the magnesium hydroxide additive ratio and the total heat release, as well as the existence of variations in CO and CO2 production for the dual flame-retardant recycled paper material. A database for combustion gases was also obtained. It was confirmed that the fire performance was improved by confirming that the total heat release decreased by 52% from the previous one in the magnesium hydroxide content of 30 g, and it was confirmed that the inflection points of the Toxic Index value due to the change in CO and CO2 gas production occurred in the magnesium hydroxide content of 20 g due to the improvement of the fire performance. Through the ISO 5660-1 experiment data, we have secured data that can be used as foundational information for performance-oriented fire risk assessments, thereby ensuring the fire safety of cellulose materials that are vulnerable to fire. [ABSTRACT FROM AUTHOR]

As one of the most common fossil derivatives, plastics are widely used for their exceptional chemical stability, low density, and ease of processing. In recent years, there has been a significant increase in the production of waste plastics, coupled with a low recycling rate, resulting in serious environmental pollution. To enhance the use of waste plastics, this research synthesized flame-retardant materials from hypercrosslinked polystyrene with different molar fractions of flame retardants. Waste polystyrene foam was used as the raw material, while aniline, triphenylphosphine, and melamine were employed as flame-retardant additives. The flame-retardant additives were successfully doped into the porous skeleton structure of hypercrosslinked polystyrene through a chemical reaction or physical mixing to achieve in situ flame retardancy, and the materials were shaped by a phenolic resin prepolymer. Then, the samples were characterized in detail, and the results indicate that the addition of a flame retardant enhances the flame retardancy of the material. In addition, the material has excellent thermal insulation performance, with a minimum thermal conductivity of 0.04176 W/(m·K). [ABSTRACT FROM AUTHOR]

Struvite precipitation is an efficient approach to recover phosphorus and ammonium from wastewater to alleviate many operational as well as environmental issues. The sparingly soluble nature of struvite in water makes it a potential slow‐release fertilizer whose adequacy has been investigated in various soil‐based cultivation. However, struvite has diverse applications other than field usage which are yet to be explored. The review highlights the usage of struvite as a fertilizer in soil along with its other applications as a nutrient supplier in hydroponic systems, fire retardants, and sorbent for the adsorption of heavy metals, dye, and gases. The research gaps between the lab and the application of the struvite products in the market for its proper utilization have also been reported. Thus, struvite produced from wastewater can be a promising green chemistry that could replace many costly, synthetic, and harmful products, while conserving phosphorous resource at the same time. This article is categorized under:Climate and Environment > Circular EconomyEmerging Technologies > MaterialsSustainable Development > Goals [ABSTRACT FROM AUTHOR]

This research presents an innovative dual-band microstrip patch antenna design enhanced with defected ground structures (DGS) and barium strontium titanate (BST) thin film, tailored for wireless local area network (WLAN) and WiMax applications. The first design phase involved the development of an microstrip patch antenna (MPA) using an flame retardant (FR4) substrate with a permittivity (er1) of 4.3 and a thickness of 1.524 mm, enhanced with DGS. This configuration achieved a single-band resonance at 4.1 GHz, with a bandwidth of 0.82 GHz and a return loss (S11) of -32 dB. The second phase involved the integration of a BST thin film, with a high permittivity(er2) of 250 and a thickness of 0.1 mm, into the DGS-enhanced microstrip patch antenna (MPA). This modification led to a transformation in the antenna's performance, enabling dual-band operation at resonance frequencies of 2.8 GHz and 5.8 GHz. Further, there was a corresponding substantial increase in bandwidth to 1.34 GHz and 1.25 GHz, respectively, an improvement in S11 values to -16.3 dB and -21.4 dB. Moreover, and antenna's size of 14×10×1.524 mm³. The study underscores the critical role of innovative material use and design optimization in advancing antenna technology, offering significant enhancements in bandwidth, and miniaturization, for wireless communication systems. [ABSTRACT FROM AUTHOR]

Organophosphate esters (OPEs) used as flame retardants and plasticizers are additives in building and construction materials, decorations, furniture, electronic equipment, among other applications. The presence of materials containing these substances in construction and demolition waste (CDW) from weak waste management practices can result in environmental contamination. In this study, OPEs' presence in soil samples collected from a CDW landfill in Brazil was evaluated. Soil samples were collected in areas adjacent to CDW from an inert landfill, and the samples were analysed by gas chromatography coupled to mass spectrometry. The OPEs were detected in all soil samples at quantifiable concentrations ranging from 21 to 251 ng g−1, and detected compounds were tris(phenyl) phosphate, tris(2-butoxyethyl) phosphate, tris(1,3-dichloroisopropyl) phosphate, tris(2-chloroisopropyl) phosphate and 2-ethylhexyl diphenyl phosphate. The presence of these compounds in a CDW landfill is probably due to the lack of control of the materials sent to and deposited in the landfill, which, results in part from the lack of sampling and screening systems that can help identify the presence of contaminants in the CDW waste stream. This is partially due to OPEs not being considered controlled compounds under current regulations, thus screening or separation for handling of OPEs at construction and demolition work sites is rare to non-existent. The data generated in this study reveals the need for improving CDW management to minimize, if not eliminate, environmental contamination by OPEs. [ABSTRACT FROM AUTHOR]

An N, P co‐doped carbon quantum dot (NP‐CQD) was prepared using citric acid as the carbon source and hexachlorotripolyphosphonitrile as the nitrogen and phosphorus source. The structure and morphology of NP‐CQD were characterized. Subsequently, NP‐CQD was blended with ammonium polyphosphate (APP) to come into being a synergistic phosphorus‐nitrogen flame retardant system (SPFRS). The SPFRS was applied in epoxy resin (EP) to enhance the flame retardancy of EP. Thermal stability, flame retardancy, combustion behavior, and char residue morphology of the EP samples were determined by multiple testing methods such as thermogravimetric analysis, vertical burning (UL‐94) and limiting oxygen index (LOI) tests, microscale combustion calorimetry test, and scanning electron microscopy. When the weight ratio of NP‐CQD to APP was kept at 1:9 and 8% SPFRS was added to EP, the obtained flame‐retardant EP (EP/CQD‐APP2:18) passed the UL‐94 V‐0 level and the LOI value of EP/CQD‐APP2:18 reached 33.2%. The MCC test showed that the heat release capacity (HRC) of EP/CQD‐APP2:18 was reduced by 48.7% compared with pure EP. Morphology observation on the char residue of EP/CQD‐APP2:18 after the UL‐94 test indicated that the addition of SPFRS promoted the formation of the dense char residue layer to improve the flame retardancy of EP. Highlight: An N, P co‐doped carbon quantum dot (NP‐CQD) was prepared and applied as a flame retardant.NP‐CQD and ammonium polyphosphate (APP) showed synergistic flame retardancy in epoxy resin.The proper weight ratio of NP‐CQD to APP was 1:9. [ABSTRACT FROM AUTHOR]

Excellent flame resistance is supposed to be taken into consideration for electronic packaging materials due to the spontaneous combustion of short circuits, except for good mechanical and dielectric properties. Herein, a hyperbranched polyborosiloxane (HPSiB) flame retardant was synthesized via a simple one‐pot transesterification as a multifunctional additive for cyanate ester (CE) resin. The HPSiB with many active terminals features good compatibility with the resin matrix, while catalyzing the curing reaction that conducts at a lower temperature. With as little as 2 wt% HPSiB incorporated, the HPSiB/bisphenol A cyanate ester (BADCy) resin achieves a UL‐94 V0 rating and 32.4% LOI value, and its peak heat release and total smoke production are simultaneously reduced. Its flexural strength and impact strength were significantly enhanced by 30.0% and 85.4%. Besides, the minimum values of dielectric constant and loss can reach 2.77 and 0.0024 at 10 GHz, which are, respectively, reduced by 7.9% and 88.5%. The integration of unique hyperbranched SiOB backbone of HPSiB with CE crosslinked network was responsible for the enhanced overall performance. This work paves a facile strategy to develop multifunctional flame retardant as a promising candidate for the high‐performance electronic packaging materials. Highlights: A novel hyperbranched polyborosiloxane flame retardant was synthesized.HPSiB shows good compatibility and catalyzes the curing reaction of CE resin.HPSiB/CE resin with significantly enhanced flame retardancy was obtained.Simultaneously high toughness and low dielectric loss were achieved.Hyperbranched structure containing SiOB chains led to the great enhancement. [ABSTRACT FROM AUTHOR]

Conventional intumescent flame retardant (IFR) is comprised of multiple components (acid, carbon, and gas source). In comparison, "all‐in‐one" design of mono‐component IFR is effective to impart the homogeneity to functional sources in polymer matrix, which is significant to improve the synergy against combustion. In this work, a core‐shell structured mono‐component IFR (MAPP@FDS) are prepared with ammonium polyphosphate (APP) and furfural‐derived Schiff base (FDS) and applied to modification of thermoplastic polyurethane (TPU). TPU composite with the as‐prepared mono‐component IFR (TPU/MAPP@FDS) exhibits V‐0 rating in UL‐94 test and a limiting oxygen index (LOI) value of 32.0%, with prominent bulkiness of carbonaceous layer. Cone calorimetry tests (CCTs) showed a significant reduction in total heat release (THR) and peak heat release rate (pHRR) for TPU/MAPP@FDS compared with the TPU composites with multi‐component IFR. By analyzing the morphology and composition of residual char, the flame‐retardant mechanism of TPU/MAPP@FDS is reasonably proposed. This work illustrates the superiority of the integration to prepare mono‐component IFR and provides a potential method in developing TPU composites with remarkable flame retardancy. Highlights: TPU/MAPP@FDS achieves a LOI value of 32.0% and UL‐94 V‐0 rating.TPU/MAPP@FDS exhibits significantly enhanced flame retardancy compared with TPU composites incorporated multi‐component IFR.The synergy in multi‐component IFR is prominently strengthened. [ABSTRACT FROM AUTHOR]

The development of flame-retardant materials has become an important research direction. For the past dozen years, researchers have been exploring flame retardants with high flame-retardant efficiency, low toxicity, less smoke, or other excellent performance flame retardants. Therefore, this work aimed to synthesize new cyclodiphosph(V)azane derivatives and their Cu(II) and Cd(II) metal complexes and investigated their potential applications as high flame-retardant efficiency. Various techniques were used to characterize the prepared ligand H2L and its metal complexes, including elemental analyses, mass spectra, conductivity measurements, electronic spectral data UV–vis, FT-IR, 1H,13C-NMR, TGA, XRD, and molecular docking experiments studies were M. tuberculosis receptors (PDB ID: 5UHF) and the crystal structure of human topoisomerase II alpha (PDB ID: 4FM9). Wood-based paint was physically mixed with the ligand H2L and its metal complexes. The obtained results of mechanical characteristics of the dried paint layers were noticed to improve, such as gloss value, which ranged from 85 to 95, hardness 1.5–2.5 kg, adhesion 4B to 5B, and impact resistance, which improved from 1.3 to 2.5 J. Moreover, the obtained results of flame-retardant properties showed a significant retardant impact compared to the blank sample, such as ignitability, which includes the heat flux which increased from 10 to 25 kW/m2, and ignition time, ranging from 550 to 1200 s, respectively, and limiting oxygen index (LOI) (%) which has been increased from 21 to 130 compared with the plywood sample and sample blank. The ordering activity of the observed results was noticed that coated sample based on Cd(II) metal complexes > coated sample based on Cu(II) metal complexes of Cyclophosphazene ligand > coated sample based on phosphazene ligand H2L > coated sample without additives > uncoated sample. This efficiency may be attributed to (1) the H2L is an organophosphorus compound, which contains P, N, Cl, and aromatic six- and five-member ring, (2) Cu(II) and Cd(II) metal complexes characterized by high thermal stability, good stability, excellent performance flame retardants, and wide application. [ABSTRACT FROM AUTHOR]

Highlights Globally, with the advancement of industrialization and globalization, the automotive sector has drastically increased for transportation and commercial purposes. Hence, to maximize efficiency and minimize the weight of automobiles, the automotive and aerospace industries have welcomed synthetic fibre‐reinforced composites, vastly replacing conventional metals. Despite the superior performance, the usage of synthetic fibre composites has led to the massive dumping of automotive waste in landfills, making the land unfit for future purposes. Therefore, natural fibre‐reinforced composites (NFRCs) quickly replace synthetic fibres with their unique features, such as being lightweight, biodegradable, and non‐toxic, en routing a new path towards a sustainable environment. Though NFRCs are finding new applications in various industries, researchers are trying to enhance their thermal, electrical, and mechanical properties to make them synergic composites. However, with the presence of cellulose, lignin, and wax, natural fibres become highly responsive toward flammability, limiting their use in various emerging applications. As the subject of the flammability of NFRCs has a limited amount of literature, the current review article aims to address the current flammability studies and strategies adopted to improve the flame‐retardant characteristics of NFRCs exclusively. Also, this review covers the factors and influence of different types of flame‐retardant fillers adopted to improve the flame retreatant characteristic of NFRCs and their mechanism. Additionally, this review article summarises various official and laboratory flame‐testing techniques such as radial panel test (RPT), cone calorimetry, and limited oxygen index (LOI) adopted to characterize the flammable properties of NFRCs. Natural fiber biocomposites are becoming a potential candidate for structural and interior applications in the automotive and aircraft industries. Flammability becomes a major alarm as it concerns with the safety of passengers. The flammability behavior of natural fiber composites is extensively discussed. Mechanisms, factors, and selection of flame‐retardant materials are reviewed to improve the flame‐retardant characteristics. The influence of surface treatments, fiber content, and flame‐retardant nanofillers are also elaborately discussed. Advanced flame testing techniques were conversed with pictorial representation. [ABSTRACT FROM AUTHOR]

Conventional intumescent flame retardants (IFRs) have demonstrated remarkable efficacy in augmenting flame retardancy but often increase smoke release. To improve the smoke suppression effect of IFRs, this study employed a one-pot method to prepare a loaded core–shell flame retardant material, namely APP@PMA–LDH. This was achieved by supramolecular assembly of phytic acid (PA) and melamine (MA) to form melamine phytate (PMA), which was coated onto ammonium polyphosphate (APP) and loaded with layered double hydroxide (LDH). APP@PMA–LDH was then compounded with a carbonized foam agent (CFA) and polypropylene (PP) to produce PP composite materials. The experimental results showed that the sample containing APP@PMA-LD H1.0 (with 1 wt% LDH) exhibited the highest effects, with a substantial reduction of 68.4% in the peak heat release rate and a 59.5% decrease in total smoke production relative to PP. Furthermore, the sample attained a limiting oxygen index of 30.3% and achieved the UL-94 V-0 rating. The analysis revealed that APP@PMA–LDH promotes the development of a dense and stable graphitic char layer on the surface of PP, reducing internal porosity and effectively hindering the emission of flammable volatile substances, thus increasing the flame retardancy and smoke suppression of PP. [ABSTRACT FROM AUTHOR]

Metal‐Organic Framework (MOF) materials can be used as flame‐retardants and smoke suppressants for polymers. As a MOF material, UIO‐66(Zr) possesses higher thermal stability and controllable pore size. In this paper, UIO‐66(Zr), NH2‐UIO‐66(Zr), and SiO2, MWCNT, and GO functionalized NH2‐UIO‐66(Zr) was fabricated to improve the flame retardant and smoke suppression performance of thermoplastic polyurethanes (TPU). The experimental results show that compared with neat TPU (LOI value 19.1 %), 2 % usage of UIO‐66(Zr) and NH2‐UIO‐66(Zr) can endow TPU with 26 % LOI value and vertical combustion rating of V‐1. Moreover, SiO2, MWCNT, and GO functionalized NH2‐UIO‐66(Zr) provide TPU with above 27.8 % LOI value and vertical combustion rating of V‐0. Meanwhile, the CCT results showed that the peak heat release rate and total heat release of TPU‐U5 (added 2 % GO‐modified NH2‐UIO‐66(Zr)) are 299.52 Kw ⋅ m−2 and 68.21 MJ m−2, much lower than that of neat TPU, which are 1180.05 Kw ⋅ m−2and 104.87 MJ m−2, respectively. The TGA, char residue EDS and XRD analysis show that SiO2, MWCNT, and GO functionalized NH2‐UIO‐66(Zr) could generate zirconium metal oxide during the combustion process, which acts as a physical barrier to prevent the TPU matrix by promoting the generation of carbonization layer. The zirconium metal oxide and carbonization layer also can confine flammable gases, which can delay the ignition time and hinder the overflow of gas. In addition, NH2‐UIO‐66(Zr) could generate non‐flammable N2 diluting the concentration of flammable gases. The mechanical properties of TPU composites can maintain more than 87 % of the neat TPU after the addition of 2 % SiO2, MWCNT, and GO functionalized NH2‐UIO‐66(Zr). These results indicate that functionalized Zr‐MOFs composites could act as excellent flame‐retardants in TPU. [ABSTRACT FROM AUTHOR]

Human parainfluenza virus type 3 (HPIV3) is a major pediatric respiratory pathogen lacking available vaccines or antiviral drugs. We generated live-attenuated HPIV3 vaccine candidates by codon-pair deoptimization (CPD). HPIV3 open reading frames (ORFs) encoding the nucleoprotein (N), phosphoprotein (P), matrix (M), fusion (F), hemagglutinin--neuraminidase (HN), and polymerase (L) were modified singly or in combination to generate 12 viruses designated Min-N, Min-P, Min-M, Min-FHN, Min-L, Min-NP, Min-NPM, Min-NPL, Min-PM, Min-PFHN, Min-MFHN, and Min-PMFHN. CPD of N or L severely reduced growth in vitro and was not further evaluated. CPD of P or M was associated with increased and decreased interferon (IFN) response in vitro, respectively, but had little effect on virus replication. In Vero cells, CPD of F and HN delayed virus replication, but final titers were comparable to wild-type (wt) HPIV3. In human lung epithelial A549 cells, CPD F and HN induced a stronger IFN response, viral titers were reduced 100-fold, and the expression of F and HN proteins was significantly reduced without affecting N or P or the relative packaging of proteins into virions. Following intranasal infection in hamsters, replication in the nasal turbinates and lungs tended to be the most reduced for viruses bearing CPD F and HN, with maximum reductions of approximately 10-fold. Despite decreased in vivo replication (and lower expression of CPD F and HN in vitro), all viruses induced titers of serum HPIV3-neutralizing antibodies similar to wt and provided complete protection against HPIV3 challenge. In summary, CPD of HPIV3 yielded promising vaccine candidates suitable for further development. [ABSTRACT FROM AUTHOR]

An issue related to the use of hemp bundle insulation for building structures is to ensure their fire resistance under the action of a low-calorie ignition source. Therefore, the object of research was the change in the properties of the insulation during fire protection with its compositions capable of forming a layer of pinocoke under the influence of high temperature. On the basis of experimental data, it was established that at fire protection of insulation with a fire retardant agent, hydrolytic stable ethers containing phosphorus and nitrogen atoms are formed on the surface of the fibers. According to the temperature values and the shape of peaks on the DTA curve, it was established that at fire protection, the height of the peaks decreases and the width increases, which characterize the flow of exothermic transformations and the destruction of hemp fibers. At the same time, it was established that the formed residue has 13.3 % for impregnation and 26.6 % for coating. It has been proven that in the process of thermal action on the fire-resistant coating, the heat insulation process of the insulation consists in the formation of soot-like products on the surface of the material. So, it was determined that the sample did not catch fire, it was charred in the place of the radiation panel, and the burning was not recorded. On the other hand, for a sample of insulation treated with a coating during thermal action, the formation of a heat-insulating layer of foam coke occurred, which inhibits the penetration of heat, the temperature of flue gases did not exceed 100 °C, and the flammability index was 0. The practical significance is that the results were taken into account when designing buildings and structures. So, there are reasons to assert the possibility of targeted regulation of fire protection processes of insulation by applying coatings that form a protective layer on the surface of the material [ABSTRACT FROM AUTHOR]

In the present paper, crosslinked polyvinyl alcohol (PVA) membranes with high transparency and excellent flame retardancy were obtained by blending 2‐methyl‐2,5‐dioxo‐1,2‐oxaphospholane (OP) with a PVA water solution at the molecular scale. Fourier transform infrared spectrometry and differential scanning calorimetry were used to investigate the crosslinking reaction. The surface morphology and micromechanical assessments of the membrane were examined using nanoindentation. The limited oxygen index (LOI) and vertical flame microscale combustion calorimetry, thermogravimetric analysis, scanning electron microscopy (SEM), energy‐dispersive spectroscopy (EDS), and x‐ray photoelectron spectroscopy (XPS) were employed to evaluate the flame retardancy and reveal the corresponding mechanisms. It was found that OP reacted with PVA below 120°C. The crosslinked membranes have a rougher surface and higher hydrophilicity and lower hardness and modulus than pure PVA does. The crosslinked membranes exhibit enhanced flame retardancy and high transparency. The membrane passes the UL 94 V 0 rating with an LOI of 27.6% and achieves a transmittance of 90.2% when the OP content is 20 wt.%. The SEM, EDS, and XPS results demonstrate that the interaction between OP and PVA effectively promotes the formation of a continuous and stable char in the condensed phase. [ABSTRACT FROM AUTHOR]

For obtaining flame retardant, oil resistance, high strength, and softness EVA/POE‐g‐MAH composites for cables, multifunctional modified magnesium hydroxide (MH‐KH570), and aluminum hydroxide (ATH‐KH570) were prepared by grafting γ‐(methacryloyloxy) propyltrimethoxysilane (KH570) onto the surface of MH and ATH. The successful grafting was confirmed by Fourier‐transform infrared spectrometer, scanning electron microscope, thermogravimetric analysis, and contact angle test. The hydrophobicity of MH and ATH was enhanced and the decompose time was extended, called the "sustained release" effect. The ethylene‐vinyl acetate copolymer (EVA)/maleic anhydride grafted polyolefin elastomer (POE‐g‐MAH) composites containing 62.5 wt% the mixture of MH‐KH570 and ATH‐KH570 in a 1:1 mass ratio was prepared. The vertical combustion test, limited oxygen index (LOI), and cone calorimetry proved the flame retardancy performance of the EVA/POE‐g‐MAH composites were enhanced, because of the homogeneous dispersion and the "sustained release" effect of MH‐KH570 and ATH‐KH570. The vertical combustion and LOI reached V‐0 and 38.1%. Importantly, the "crosslinking" effect of MH‐KH570 and ATH‐KH570 further enhanced the tensile strength after the composites crosslinked, and reached 19.9 MPa. In a word, a simple method for preparing flame retardant EVA/POE‐g‐MAH composites with high tensile strength was provided. [ABSTRACT FROM AUTHOR]

In this study, an eco‐friendly approach is presented for the innovative use of waste oyster shell (OS) powder modified with zinc stannate, aliphatic alcohols, and silane coupling agents blended with styrene‐butadiene‐styrene (SBS) modified asphalt to make a flame‐retardant binder (modified oyster shell [MOS]/styrene‐butadiene‐styrene [SBS]/MA), which is rendered flame retardant and smoke suppressive. Compared with the original SBS/MA, MOS/SBS/MA with a 2% addition rate showed a 35.44% increase in ultimate oxygen index, a 30.62% reduction in peak exotherm, a 10.87% reduction in smoke density, and a 75% reduction in volatile organic compound (VOC) emissions. It also has excellent mechanical properties, with increases in composite modulus, elastic modulus, and storage modulus of 68.58%, 97.29%, and 59.59%, respectively, at 46°C. The thermal stability of MOS/SBS/MA is also improved, with a decomposition temperature 26°C higher than that of SBS/MA. Pavement performance tests show that the water‐soaked Marshall's split strength has increased by 3.87% and the coefficient of rutting by 3.51%. Increased by 3.51%, this method effectively utilizes the waste OS, improves the fire‐retardant properties of asphalt while retaining the mechanical properties of the modified asphalt binder, and provides a model for developing sustainable fire‐retardant asphalt in coastal areas. [ABSTRACT FROM AUTHOR]

OPFRs are emerging environmental pollutants with reproductive and endocrine toxicity. This study aimed to examine the association between environmental exposure to OPFRs during early pregnancy and GDM. This nested case–control study was based on a birth cohort that was constructed at a maternal and child health hospital, including 74 cases of GDM among 512 pregnant women. The OPFRs, including TBP, TBEP, TCEP, TDCPP, TMCP, TOCP, and TPHP during 10–14 weeks of pregnancy were determined using GC–MS. The association between the OPFRs and GDM was assessed using WQS and BKMR models. The levels of OPFRs were significantly elevated in GDM patients (60) compared with the controls (90). The WQS analysis showed that mixtures of the OPFRs were significantly associated with GDM (OR 1.370, 95% CI 1.036–1.810, P = 0.027), and TBP, TPHP, and TMCP were the major contributors to the mixed exposure effect. In the BKMR model, individual exposure to TBP, TPHP, and TMCP, and the interaction of TMCP with TBP and TPHP were significantly associated with GDM. Environmental exposure to OPFRs is positively associated with GDM. These findings provide evidence for the adverse effects of OPFR exposure on the health of pregnant women. [ABSTRACT FROM AUTHOR]

Increasing demand for electrical and electronic equipment results in the generation of a rapidly growing waste stream, known by the acronym WEEE (waste electrical and electronic equipment). The purpose of this study was to evaluate the effectiveness of green sink–float treatment in sorting plastic polymers typically found in WEEE (PP, ABS, PA6, PS, and PVC). Molasses, a by-product of sugar bio-refining, was added in various concentrations to water to form solutions at different densities. The methodology was initially tested on virgin polymers; later, it was applied to plastics from a WEEE treatment plant. The polymers were characterised through near infrared spectroscopy (NIRS) and Fourier-transform infrared spectroscopy (FTIRS) analyses; the detection of any additives and flame retardants was conducted using the sliding spark technology (SSS2) and scanning electron microscope (SEM—EDX). The results showed that, for plastics from WEEE, the recovery efficiency was 55.85% for PP in a solution of tap water while the remaining part of PP (44.15%) was recovered in a solution of water to which 90% molasses was added. Furthermore, 100% recovery efficiency was obtained for PS and 93.73% for ABS in a solution of tap water with the addition of 10% w/v molasses. A recovery efficiency of 100% was obtained for PVC and 100% for PA6 in a solution consisting solely of molasses. [ABSTRACT FROM AUTHOR]

Organophosphorus flame retardants (OPFRs) can damage the brain and may cause abnormal behaviors. There was no population-based study to reveal the relationship between OPFRs and the occurrence of depression. This study utilized a publicly available database to investigate the correlation between OPFRs exposure and the risk of depression, and the mediation effect of inflammation on the correlation. Data in this study was from the database of the National Health and Nutrition Examination Survey. Multifactorial logistic regression was used to estimate the relationship between OPFRs exposure and the risk of depression, and a mediation effect model was constructed to explore the impact of inflammation on the correlation. Data of 1273 participants was included in the study. It was found that individuals with high urinary concentration of bis-(2-chloroethyl) phosphate had an increased risk of developing depression (OR = 1.217, 95 % CI: 1.032–1.435). Combined exposure to OPFRs was significantly associated with the increased risk of depression than single OPFRs exposure. Subgroup analyses based on inflammatory levels in the body revealed that inflammation might exert the mediation effect on the association between OPFRs exposure and the risk of depression, with the contribution proportion of 8.23 %. Cross-sectional data and rapid metabolism of OPFRs lead to uncertainty in revealing long-term exposure in the body. There was a correlation between OPFRs exposure and the risk of depression, which may be mediated by inflammation in the body to some extent. • OPFRs exposure is a risk factor for depression. • Combined exposure to OPFRs causes a higher risk of depression than single exposure. • The inflammatory status may be involved in the depression caused by OPFRs. [ABSTRACT FROM AUTHOR]

Despite the mechanical and physical properties of polyurethane foams (PUF), their application is still hindered by high inflammability. The elaboration of effective, low-cost, and environmentally friendly fire retardants remains a pressing issue that must be addressed. This work aims to show the feasibility of the successful application of natural nanomaterials, such as halloysite nanotubes and nanocellulose, as promising additives to the commercial halogen-free, fire-retardant triphenyl phosphate (TPP) to enhance the flame retardance of open-cell polyurethane foams. The nanocomposite foams were synthesized by in situ polymerization. Investigation of the mechanical properties of the nanocomposite PUF revealed that the nanoscale additives led to a notable decrease in the foam's compressibility. The obtained results of the flammability tests clearly indicate that there is a prominent synergetic effect between the fire-retardant and the natural nanoscale additives. The nanocomposite foams containing a mixture of TPP (10 and 20 parts per hundred polyol by weight) and either 10 wt.% of nanocellulose or 20 wt.% of halloysite demonstrated the lowest burning rate without dripping and were rated as HB materials according to UL 94 classification. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) foams have the characteristics of being lightweight and high strength, as well as offering good heat resistance, minimal water absorption, etc., and they have been widely used in the wind power field. In addition, they are being promisingly applied in automotive, rail, marine, construction, and other related fields. Therefore, the flame retardancy(FR) of PET foams is an issue that requires investigation. The addition of flame retardants would affect the chain extension reaction, viscoelasticity, and foamability of PET. In this study, zinc diethyl hypophosphite (ZDP) and decabromodiphenylethane (DBDPE) were used to form a synergistic FR system, in which ZDP is an acid source and DBDPE is a gas source, and both of them synergistically produced an expanded carbon layer to improve the flame retardancy of PET foams. The ratio of ZDP and DBDPE is crucial for the carbon yield and the expansion and thermal stability of the char layers. At the ZDP/DBDPE ratios of 9/3 and 7/5, the thickness of the char layers is about 3–4 mm, the limiting oxygen index (LOI) values of FR modified PET are 32.7% and 33.6%, respectively, and the vertical combustion tests both reached the V-0 level. As for the extruded phosphorous/bromine synergism FR PET foams, ZDP/DBDPE ratios of 3:1 and 2:1 were applied. As a result, the vertical combustion grade of foamed specimens could still reach V-0 grade, and the LOI values are all over 27%, reaching the refractory grade. [ABSTRACT FROM AUTHOR]

With the rapid development of electronic information technology, higher requirements have been put forward for the dielectric properties and load-bearing capacity of materials. In continuous glass fiber-reinforced thermoplastic composites, polypropylene matrix is a non-polar polymer with a very low dielectric constant and dielectric loss, but polypropylene is extremely flammable which greatly limits its application. Aiming at the better application of flame retardant-modified continuous glass fiber-reinforced polypropylene composites (FR/GF/PP) in the field of electronic communication, the effects of four different kinds of flame retardants (Decabromodiphenyl ethane (DBDPE), halogen-free one-component flame retardant (MONO), halogen-free compound flame retardant (MULTI), and intumescent flame retardant (IFR)) on the properties of FR/GF/PP were compared, including the mechanical properties, dielectric properties and flame-retardant properties. The results showed that among the FR/GF/PP, IFR has the highest performance in mechanical properties, MULTI has better performance in LOI, DBDPE and IFR have better performance in flame retardant rating, and DBDPE and IFR have lower dielectric properties. Finally, gray relational analysis is applied to propose an approach for selecting the optimal combination (flame retardant type and flame-retardant content) of comprehensive performance. In the application exemplified in this paper, the performance of IFR-3-modified GF/PP is optimized. [ABSTRACT FROM AUTHOR]

This research studies natural rubber (NR) composite blends prepared with recycled polyethylene (PE), polyurethane waste (PU), silica (SiO2), and aluminum trihydroxide (ATH) under the proper mixing conditions using an internal mixer and a two-roll mill. The mechanical, impact, dynamic mechanical, and thermal properties, together with flammability, were investigated. NR/PU composites filled with a specific SiO2/ATH concentration resulted in excellent flame-retardant properties without using PE. Adding PE causes poor flammability, while using PU and SiO2 prevents flame extensibility of the composites. In addition, SiO2 and ATH synergistically improved both mechanical and dynamical mechanical properties. This is attributed to the reinforcement of SiO2 particles inside the matrix, whereas the ATH releases water as a flame retardant. The V-0 composites tested with UL-94 showed acceptable heat resistance, strength, and durability, making them suitable for interior and exterior applications in buildings without the lightweight requirement. [ABSTRACT FROM AUTHOR]

This research aims to improve the flame-retardant properties of wood–plastic composites with different recycled plastics. Acrylonitrile butadiene styrene (ABS) and polyvinyl chloride (PVC), flame-retardant materials, and recycled polypropylene (PP) were used as matrix in this research. Recycled ethylene propylene diene monomer (EPDM) with flame-retardant properties was also added to mix with rubberwood flour (RWF) to improve mechanical properties. The rubberwood flour, coupling agent (MAPP), and lubricant are fixed at 44.5%, 4%, and 1%, respectively, whereas recycled plastics and EPDM rubber contents are in the range of 30.5–50.5% and 0–20%, respectively. The composite materials were manufactured into panels using a twin-screw extruder and hot press machine. The experimental results were statistically analyzed by analysis of variance (two-way ANOVA) at a 95% confidence level. The highest values of the mechanical parameters of wood–plastic composites reinforced with recycled polypropylene (RWF44.5PP50.5) were 15.89 MPa, 42.26 MPa, 41.79 MPa, and 0.0202 J for tensile strength, flexural strength, compression strength, and impact strength, respectively. An increasing EPDM rubber content of wood–plastic composites provided better thermal properties. The thermogravimetric analysis and differential scanning calorimetry of hybrid composites with recycled ABS (RWF44.5ABS30.5EPDM20) obtained the highest value with thermal stability in the range of 255–284 °C. For the flammability properties, the hybrid composites with high EPDM rubber content were less flammable. Recycled PVC with content of RWF44.5PVC50.5 outperformed hybrid composites reinforced made from ABS and PP in terms of UL-94 and the limiting oxygen index with values of 25.73%. [ABSTRACT FROM AUTHOR]

As one of the most effective fire prevention measures, the ultra-thin intumescent fire-retardant coating (IFRC) is widely used to coat the surface of steel structure in buildings. The aim of this work was to investigate the pyrolysis characteristics, kinetics and flame-retardant mechanism of ultra-thin IFRC for dealing with the fire hazards of steel structures. Thermogravimetric experiments were carried out at multiple heating rates. The thermogravimetric analysis results showed that the whole thermal degradation process could be divided into two stages. In Stage I, the active filler and resin released H2O and other small molecules with the mass loss of 10%. Stage II was assigned to the intramolecular and intermolecular reactions of the matrix resin, catalyst, carbon forming agent and foaming agent in the ultra-thin IFRC, which released the flame-retardant gases NH3, H2O and CO2. The initial kinetic parameters were obtained by the model-free method, and then the shuffled complex evolution (SCE) algorithm was used to optimize these proposed kinetic parameters. Moreover, the predicted pyrolysis curves based on optimized kinetic parameters were compared with experimental data, and the good agreement was achieved. Eventually, the flame-retardant mechanism in different stages was speculated, which could provide the basis and reference for the development and application of the ultra-thin IFRC. [ABSTRACT FROM AUTHOR]

Flame‐retardant polylactic acid (PLA) composites play critical role in construction fields. However, it is urgent to develop flame‐retardant PLA composites since PLA inherent flammability and melt dripping. Herein, we utilize intumescent flame retardant (IFR) with hydroxyapatite nanowires/acidic nano ZSM‐5 (HAP/HN) as synergist to improve the PLA flame‐retardant performance. According to scanning electron microscopy (SEM) observation, HN particles were distributed around with HAP and x‐ray diffraction, Fourier transform infrared spectrum show that the HAP/HN particles were successfully developed with the interaction of hydrogen bonds. The flame‐retardant results of PLA composites showed that the limited oxygen index value increased from 18.0% of neat PLA to 38.2% for HAP/HN sample, moreover the peak heat release rate (pHRR) was lower (~65%) than that of neat PLA (553 kW/m2). In addition, the char yield of PLA/IFR/HAP/HN sample increased from 9.5% to 54.2% for PLA/IFR/HN. SEM results showed that the char surface was smoother and denser with incorporation of HAP/HN. TG‐IR test also demonstrated that the intensity of CO was decreased obviously in gas phase due to the addition of HAP. [ABSTRACT FROM AUTHOR]

To improve the flame retardancy of 3D‐printed polypropylene (PP) parts, cyclic triphosphonitrile‐based hyperbranched charring agent (DHCCP) was innovatively synthesized and applied in flame‐retardant coatings. Thermogravimetric analysis (TGA) indicated that the residual char rate of DHCCP reached 64.33% at 700°C. When 5 wt% DHCCP was added to the coating, the limiting oxygen index of the composite reached 29.1%, and the vertical combustion (UL‐94) could reach V‐0 rating. In addition, cone calorimetry test measured a 54.10% reduction in peak exothermic rate, and the tensile strength of coated PP was improved. The morphology and chemical composition of the char residues were investigated by scanning electron microscopy, infrared spectroscopy, and laser Raman spectroscopy. After combustion, the coated PP formed a continuous and dense char layer, which could play the role of heat and oxygen insulation and anti‐drip, effectively improving the flame‐retardant of 3D‐printed PP parts. [ABSTRACT FROM AUTHOR]

Traditional wood protection methods involving fire retardants and preservative paints have limitations, requiring periodic renewal during a building's lifecycle and generating hazardous waste post-use. This study aims to achieve a multifaceted solution, simultaneously enhancing wood's resistance to fire, fungi, and insects using natural and/or recycled mineral waste components containing lime that react with pozzolanic additives. Additionally, organic humates provide protection against pests (fungi and insects). Following the crystallization processes within the wood's structure, it exhibits increased resistance to fire, as demonstrated by tests involving seven species. The study also describes wood tolerance tests against termites (Reticulitermes flavipes) that yielded promising results, indicating that the treated wood is an unsuitable habitat for these pests. An additional advantage for the timber industry is that the crystallized composite filling the wood's pores minimizes wood stitching and reduces internal stresses during the drying process. This property enhances the utility of timber in frame structures and carpentry joints, which are less susceptible to moisture-induced movements. The timber impregnated by our method can also be repurposed or disposed of as non-hazardous waste. This research thus offers an eco-friendly and effective approach to wood protection. [ABSTRACT FROM AUTHOR]

In modern society, the size of buildings tends to expand due to technological advances. However, while prioritizing performance design and specific building materials, fire research has fallen short of creating a comprehensive fire characteristic database for building materials. This study presents a plan for building a big data resource to evaluate the fire performance of cellulose-based flame retardant building finishing material in buildings of varying sizes. The three types of building finishing materials applied in this study are polyurethane foam, MDF, and cellulose-based building finishing materials. The variables were determined based on the floor area, and the change in floor area was calculated using the aspect ratio, a dimensionless number. Data analysis utilized the Fire Dynamics Simulator (FDS) to determine the time required to meet life safety standards for temperature, visibility, and Fractional Effective Dose (FED). The results confirm a correlation between the safe evacuation time (ASET) and increasing floor area. Additionally, the study demonstrates that cellulose-based flame-retardant building finishing material effectively maintains safe evacuation times even with increasing floor areas, as evidenced by increases of 41.0 s, 13.2 s, and 97.5 s in temperature, visibility, and FED, respectively. [ABSTRACT FROM AUTHOR]

Fireproof coatings are the simplest, most efficient, and oldest method for protecting a wide range of flammable products, such as wood. Furthermore, surface ignition is the initial phase, so surface protection is essential to reduce fire propagation. Furthermore, delaying the spread of flames can help to save someone when a fire starts. This project synthesized flame-resistant resin starting from tetraallyloxysilane monomer as a halogen-free monomer, an intrinsic flame retardant co-curing agent. The following step synthesized polyester resin using terephthalic acid as a heat-resistant resin. Unsaturated polyester was used by bulk radical polymerization. FT-IR and 1H-NMR analysis showed the successful synthesis of the desired monomer and polymeric compound. The thermal degradation and flame retardancy of pure unsaturated polyester resin (UPE) and allyloxysilane-unsaturated polyester (AUPE) were investigated by thermogravimetric analysis (TGA/DTG/DSC). The burning test and the thermal stability of the coating layers were evaluated using standard UL 94. Physical properties of resins were evaluated using Heat Deflection Temp tests (HDT) ISO 75-A, ASTM 648, Hardness ASTM D2583, Volumetric shrinkage ASTM 3521, and Water absorption ASTM D570. The results of the tests show the successful synthesis and their flame retardant properties. [ABSTRACT FROM AUTHOR]

S-layers are crystalline arrays found on bacterial and archaeal cells. Lactobacillus is a diverse family of bacteria known especially for potential gut health benefits. This study focuses on the S-layer proteins from Lactobacillus acidophilus and Lactobacillus amylovorus common in the mammalian gut. Atomic resolution structures of Lactobacillus S-layer proteins SlpA and SlpX exhibit domain swapping, and the obtained assembly model of the main S-layer protein SlpA aligns well with prior electron microscopy and mutagenesis data. The S-layer's pore size suggests a protective role, with charged areas aiding adhesion. A highly similar domain organization and interaction network are observed across the Lactobacillus genus. Interaction studies revealed conserved binding areas specific for attachment to teichoic acids. The structure of the SlpA S-layer and the suggested incorporation of SlpX as well as its interaction with teichoic acids lay the foundation for deciphering its role in immune responses and for developing effective treatments for a variety of infectious and bacteria-mediated inflammation processes, opening opportunities for targeted engineering of the S-layer or lactobacilli bacteria in general. [ABSTRACT FROM AUTHOR]