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The purpose of this research was to formulate epoxy composites with basalt fibre and foxtail millet biosilica reinforcement for the use in horizontal and vertical wind turbine blade manufacturing. The study primarily focused on the effect of adding ceramic biosilica on mechanical, wear, flammability and thermal degradation behaviour when reinforcing with basalt fibre in epoxy resin. The biosilica particles were prepared via thermo-chemical process and silane surface-treated subsequently. The composites were developed using hand layup method and evaluated in accordance with the relevant American Society for Testing and Materials (ASTM) criteria. According to the results, the confirmation analysis confirmed the biosilica formation with via FTIR and XRD analysis. The size of biosilica produced was between 10 and 15 nm. It is further noted that the maximum values for tensile, flexural, compression, ILSS and Izod impact for composite designation EBB2 are 147 MPa, 182 MPa, 155 MPa, 27.1 MPa and 5.85 J. The SEM fractographs revealed highly reacted phases of biosilica as well as basalt fibre. It is further noted that the composite designation EBB3 has the lowest sp. wear loss of 0.0110 mm3/Nm and coefficient of friction (COF) of about 0.266. Moreover, the EBB3 composite designation also exhibits improved thermal degradation stability among all composite designations with a lowest combustion rate of 5.26 mm/min. Such improved load bearing effect, resistance to wear and thermally stable sustainable composites could be employed as working material for wind turbine applications. [ABSTRACT FROM AUTHOR]

In this study, the epoxy composites were made using Si3N4 nanoparticle obtained from red matta rice husk ash and aluminised glass/pineapple hybrid fibre. The primary objective of this study was to develop lightweight structural composites for domestic infrastructure applications using biomass wastes. The epoxy composites were made using Si3N4 nanoparticle of 0.5 to 4 vol% and hybridised fibre of 40 vol% by hand lay-up method. The mechanical, fatigue and low-velocity impact characteristics of the composites were evaluated as per ASTM standards. The results showed that, among the composites that had been produced, composites with 2 vol% Si3N4 nanoparticle had the highest tensile, impact, flexural and hardness, measuring 168 MPa, 202 MPa, 6.2 J and 93 shore-D. Also, at 50% of UTS, the composite with the addition of 2 vol% Si3N4 nanoparticle had a better fatigue life count of about 36273. Similarly, the improved low-velocity impact strength of composite having 1 vol% of Si3N4 nanoparticle has maximum energy absorption of 11.4 J. Moreover, with the insertion of stacked fibre and Si3N4 nanoparticle, the epoxy composites have low combustion rate showing better flame-retardant behaviour. The results show that composites have been successfully produced for potential applications such as domestic infrastructure products like lightweight man-hole cover, hand rails, gratings, interior decoration panels, doors and windows. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical, thermal, and morphological properties of abaca-polyester composites made using lignin from fluorescent perianths of jack fruit. The primary scope of this research is to study the viability of producing lignin from waste jack fruit fluorescent perianths and how it influence the mechanical, wear, creep and flammability properties of abaca-polyester composite. The lignin biopolymer was extracted via thermo-chemical method and composites were prepared using hand layup method. The produced composites were evaluated based on American society of testing and materials (ASTM) standards and the results revealed significant improvements in tensile and flexural strength. The addition of abaca fiber and 3.0 vol% of lignin in PA2 composite shows the highest tensile strength, while the PA3 at 5.0 vol% of lignin shows slight shortfall due to clustering of particle. However the PA3 outperform in impact strength, hardness, and wear resistance. The Flammability test reveals effective self-extinguishing properties for PA3 exhibiting superior performance due to lignin's char-forming capabilities. Moreover, creep and TGA analysis demonstrated that the incorporation of abaca fiber and lignin of 5 vol% contributed to reduced creep strain and mass loss at initial, middle and final stages. SEM analysis confirms the effective interaction of lignin particle with resin matrix and ensured effective toughening. The study concludes the optimization potential of abaca-polyester composites, with 3.0% lignin identified as an optimal concentration for balanced improvements across various properties, providing valuable insights for composite material design and applications. [ABSTRACT FROM AUTHOR]

The flammability levels, flame retardancy ratings, and reaction-to-fire (fire response) properties (under five radiant heat fluxes, i.e., 15, 25, 35, 50, and 75 kW m−2) for same real E-glass fiber-reinforced unsaturated polyester resin (UPR) composite wind turbine blade (WTB) samples were determined by experimental techniques like limiting oxygen index (LOI), vertical flame test (VFT), and cone calorimeter test (CCT). Based on typical CCT results (main test parameters), thermal and non-thermal hazard assessment index systems were selected, calculated, and compared to deduce corresponding hazard characteristics of the blade samples. The WTB shows a LOI value of 25.10% (combustible) and a non-rated (NR) UL (Underwriters Laboratories) 94 classification according to the after-flame time criterion. CCT analyses indicate that higher external heat fluxes correspond to increased peak heat release rate (PkHRR), total heat release (THR), and mass loss rate (MLR) values, and reduced ignition time (tig), flame duration (tfl), and overall flame (combustion) duration (FD) values. Meanwhile, CCT analyses indicate that higher external heat fluxes result in elevated specific extinction area (SEA), rate of smoke released (RSR), total smoke released (TSR), CO yield (COY), and CO production rate (COP) values, and relatively lower CO2 yield (CO2Y) and CO2 production rate (CO2P) values. These results reflect real WTB fires will pose severe situations with noticeable thermal and non-thermal hazards. Multiple physical and chemical evolution processes undergo in burning processes of such fires with higher PkHRR values through heat releases, transfers, exchanges, and feedback. Composite blade materials may be largely deformed and disintegrated in faster rates. Burning blade blocks may form spotting fires and cause secondary ground fires. Local air quality, visibility levels, working, and health conditions of related persons may be worsened. It is really urgent to develop mature, effective, novel, and even revolutionary fire protection and suppression technologies for such fires. [ABSTRACT FROM AUTHOR]

Densified wood (DW) is a carbon-negative and energy-saving structural material with promising applications in high-rise timber buildings. However, its fire safety issues restrict its applications. In this paper, a bio-material, phytic acid, based flame retardant PPBNOH was prepared to improve the flame retardancy of DW. The structure characteristics, thermal stability, flammability, combustion behavior and mechanical performance of flame-retardant DW (PPBNOH/DW) were studied. Results show that the decomposition of PPBNOH catalyzes char formation and enhances thermal stability. Thus, PPBNOH/DW has a 57% reduced peak mass loss rate and a 27.9% increased char yield. Both the wood dense structure and PPBNOH catalyzation synergistically promote the formation of phosphorus-containing, crosslinked and aromatic char during wood combustion, which hinders heat/mass transfers and enhances flame retardancy. Thus, PPBNOH/DW has a 53.2% limiting oxygen index, a V-0 rating of UL-94 test. It presents delayed ignition time, reduced heat release characteristics and lower heat of combustion (5.37 MJ kg−1) in the cone calorimeter test. BNOH improves the smoke suppression performance of PPBNOH/DW with a 38.6% reduced total smoke production. The compatible and thermally insulating char also enhances the high-temperature heating resistance of PPBNOH/DW as it has the highest remaining mechanical strengths after heating. [ABSTRACT FROM AUTHOR]

This research concentrates on the developmemnt of sustainable formulation of an environmentally friendly structural composite using an innovative approach, incorporating recycled materials. The primary aim of this research is to utilize the industrial wastes as re-circulated input to make structural materials without using new raw materials. Waste plastic, tanned waste leather, and waste glass fiber-reinforced plastic (GFRP) additives. The fabrication employs the hand layup method, and the composite undergoes comprehensive characterization following ASTM standards. According to the results, the composite designation "D" emerged as the most mechanically robust, with a tensile strength of 142 MPa, flexural strength of 195 MPa, compression strength of 156 MPa, interlaminar shear strength of 45 MPa, rail shear strength of 31 MPa, and an impact energy of 4.94 J. Concerning creep behavior, the "E" designation demonstrates minimal creep strain, recording values of 0.0057, 0.0076, and 0.0123 for 5000 s, 10000 s, and 15000 s time frame, respectively. This indicated the addition of 5 vol. % of GFRP additives improved the load-bearing effect. In terms of flammability, the "E" designation exhibits noteworthy flame resistance, with a low flame propagation speed of 10.83 mm/min. Additionally, the "E" designation demonstrates stable hydrophobic behavior, revealing a minimal water absorption percentage of 0.001. This study showcases the potential of the developed composite, emphasizing its mechanical strength, resistance to creep, flame retardancy, and hydrophobic properties, positioning it as an environmentally responsible and versatile material for diverse applications. [ABSTRACT FROM AUTHOR]

The primary goal of the study was to develop a green composite material for safe environmental production of human prosthetics using sea urchin (Echinoidea) spike chitin macromolecules, basalt-encapsulated bamboo fiber and epoxy. The chitin biopolymer was extracted from marine waste sea urchin spikes as first time and characterized for its physicochemical properties. The composites' mechanical properties, wear resistance, thermal conductivity, flame retardancy and water absorption were assessed for their suitability in prosthetic applications. The fabrication process adheres to the hand-layup method and follows American society for testing and materials (ASTM) procedure for characterization. Results revealed that the composite EBC3 exhibits improved tensile strength of 165 MPa, flexural strength of 224 MPa, compression strength of 198 MPa, ILSS (interlaminar shear strength) of 31.9 MPa, and impact energy of 5.8 J. Furthermore, composite EBC4 demonstrated superior wear resistance under varying loads and sliding distances. Additionally, EBC4 exhibits a highest thermal conductivity of 0.72 W/mk and a lower flame propagation speed of 5.72 mm/min. Moreover, a low water absorption, indicated by a 101° contact angle in EBC4, guarantees long-term stability of composites. [ABSTRACT FROM AUTHOR]

Green manufacturing and reducing our cultural dependency on petrochemicals have been the global interest currently, especially in the polyurethane industry segments. We report the fabrication of rigid polyurethane foams (RPUFs) and their flame-retardant property from hemp seed oil as an alternative to petrochemical-based polyols. The cold-pressed hemp-seed oil (HSO) was first oxidized to epoxidized triglyceride oils with acetic acid and hydrogen peroxide, followed by a ring-opening reaction with methanol to fabricate hemp bio-polyols. The formation of polyols was characterized using FT-IR, hydroxyl, and acid values. The bio-polyol was used in different proportions with commercial polyols and other foaming ingredients to produce rigid polyurethane foams via a one-step process. Dimethyl methylphosphonate (DMMP), triethyl phosphate (TEP), and expandable graphite (EG) were added during the foam preparation to improve flame retardancy. The produced foams were analyzed for their apparent density, mechanical properties, thermal degradation behavior, closed cell content, flammability, and cellular morphology. The effect of different flame retardants had a significant influence on the cellular structures, closed-cell content, density, and compressive strength of the polyurethane. A significant improvement in anti-flaming properties was observed as the neat HSO-based foam showed a burning time of 110 s and a weight loss of 82%, whereas 10 wt% of TEP displayed a reduced burning time and weight loss of 19 s and 5%, respectively. DMMP and EG-based RPUFs exhibited similar flame retardancy and mechanical properties relative to neat HSO-based foam. The results demonstrated in this work proposed a potential combination of bio-polyols and commercial polyols as a strategy to fabricate flame-retardant polyurethane foam for high-performance applications. [ABSTRACT FROM AUTHOR]

Innovative and cost-effective paper sheets with superior fire safety and reinforcement properties have been developed. The paper sheets were fabricated via valorization of agricultural waste to paper and then coated with nanoparticles. Paper attained from rice straw was used to create the sheets. Afterward, bentonite sheets were incorporated in these sheets, and finally, PbO nanoparticles were coated on prepared paper nanocomposites. The mass ratio of bentonite sheets was altered. The flammability and mechanical properties of the developed paper nanocomposites were studied. The flame retardancy of developed paper nanocomposite was significantly improved achieving LOI value of 24% compared to 20% for bentonite and PbO nanoparticle-free sample. Additionally, the tensile strength was improved recording 44% enhancement compared to unmodified sample. Furthermore, the flame retardancy mechanism was proposed and studied. [ABSTRACT FROM AUTHOR]

Cotton fabrics are widely used in clothing, packaging, and medical applications because of their excellent comfort, breathability, and low cost. However, it poses a threat to use them in specific scenarios, where flame retardance and antibacterial activity are highly desired. In this work, we propose the functionalization route by using layer-by-layer assembly of polyethyleneimine (PEI), phytic acid (PA), iron (Fe3+), and aluminum (Al3+) ions on cotton fabrics. Interestingly, the modified cotton fabric showed good biocompatibility in the cell viability (> 70%) and hemolysis (< 3%) test. In addition to biocompatibility, the antibacterial performance was largely improved for the modified cotton fabric with the antibacterial efficacy of > 99% due to the presence of Fe3+ and Al3+ that work in a synergistic manner. In term of flame retardance, the modified cotton fabric exhibited self-extinguishing characteristics in vertical burning experiments, with the Limiting Oxygen Index (LOI) of 35.0%. The excellent flame-retardant property was further supported by the results in cone calorimetry test, thermal gravimetric analysis, and TG-IR test, elucidating the underlying mechanism that rapid formation of dense char layer by the thermal decomposition of PEI/PA/FeAl system is effective to prevent the spreading of flame and thus protect the cotton from burning. This work provides a strategy to achieve multifunctionality on cotton fabrics, which may inspire the design on other types of fabrics or materials for extended applications. [ABSTRACT FROM AUTHOR]

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Printed circuit board application shows how banana fiber-reinforced polymer composites can be used to make printed circuit boards (PCBs). The study looks into how well banana fiber works as a reinforcement material for polymer composites and how it could be used to make PCBs. The banana fabric is treated with alkali to improve its mechanical properties. It is then mixed with epoxy resin to make a composite material. The composite's mechanical, thermal, and electrical properties were characterized. The results showed that the banana fiber-reinforced composites exhibited comparable mechanical properties and thermal stability to the conventional substrates. The dielectric constant and loss tangent of the composite were also within the acceptable range for PCB applications. The paper concludes that banana fabric-incorporated polymer composites have great potential for PCB fabrication, especially in applications where environmental sustainability is a priority. The use of natural fibers like banana can reduce the environmental impact of PCB fabrication while also providing good mechanical and electrical properties. This study opens up new opportunities for the use of natural fiber-reinforced composites in the electronics industry. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) and zinc oxide-silicon dioxide (ZnO-SiO2) nanomaterials were successfully incorporated into cotton fabric yarn using a single step sonochemical method in aqueous medium. The resulting cotton fabrics were evaluated for the ultraviolet (UV) blocking properties using ultraviolet-diffused reflectance spectroscopy (UV-DRS), wetting studies measured by contact angle, and flammability test by vertical flame test (VFT) method. The hydrodynamic diameter of the incorporated nanomaterials was in the range of 30–600 nm. 1, 2, 3, 4-butanetetracarboxylic acid (BTCA) was used as a cross-linking agent between the free -OH groups of the cotton fabric yarns. The results of ZnO-SiO2 incorporated cotton fabric exhibited 8.8% enhancement in UV-B blocking, wettability of 124.5° and flame time of 9 ± 1 s as compared to control cotton fabric. The UV blocking by ZnO-SiO2 incorporated cotton fabric was retained even after 10 washing cycles. The study highlights a single step method for the simultaneous in-situ synthesis and incorporation nanomaterials in cotton fabrics sonochemically as an alternative method for enhanced multifunctionality. [ABSTRACT FROM AUTHOR]

The change in the content and composition of polycyclic aromatic hydrocarbons (PAHs) was studied in organic horizons of soils of the boreal zone subjected to combustion under oxygen deficiency conditions. Organic soil horizons from the oligotrophic bog and two types of forest ecosystems (lichen pine and green moss spruce forest) were analyzed. It was found that combustion conditions, the composition of burned organic material, and its flammability influence significantly the content and composition of PAHs. Polyarenes are formed, for the most part, at 300°C. As compared to original samples, their content increases from 2.7 to 9.7 times. The maximum content of PAHs in the samples is reached at 300°C, whereas it falls by 5.8–33.0 times at 500°C. An abrupt decrease in the PAHs content is probably due to the decomposition to simpler substances. The experimentally obtained ratio of low-molecular weight to high-molecular weight polyarenes, which exceeds one, may indicate the pyrogenic origin of PAHs. [ABSTRACT FROM AUTHOR]

This study is the first part of a larger investigation into the fire behaviour of green façades. In this study, the currently known international research status on this topic is presented and discussed. In addition, the flammability of green façades is investigated through 43 fire tests on a medium scale according to the SBI (Single Burning Item) test method EN 13823. The focus of the investigation was placed on climbing plants. A total of 25 different plant species were investigated. A comparison of the heat release rate of all the investigated vital plants shows similar behaviour. In the course of exposure, there are short peaks in the heat release rate. These peaks are "flare-ups" that occur when parts of the plants dry out due to exposure to the flame and then ignite. The plant species itself had no substantial influence on fire behaviour. Horizontal fire spread occurred to a very limited extent within the investigations of vital plants. They were self-extinguishing. The significant factor in the assessment of flammability is the moisture content of the plants. With dried plants, an abrupt heat release occurs at the beginning. Dried-out plants, as well as unmaintained plants with a high content of deadwood, represent the most critical case. [ABSTRACT FROM AUTHOR]

A series of trials were conducted to investigate the repeatability of furniture-scale calorimetry experiments. Twenty-five identical upholstered chairs were ignited under the same experimental conditions. Experimental results of heat release rate (HRR), mass loss rate (MLR), and emission yields (CO, CO2, N2O, NO, CH4, HCN) are presented. Discrepancies were observed between the time resolved evolution of the various recorded data. However the development of each fire was observed to be tied to common events. By accounting for these events, a more consistent representation of the burning behaviour can be expressed. Each experiment displayed distinct burning regimes (i.e., pyrolysis, flaming, and smouldering) which were identified through visual observation and through analysing the emission data. Some species yields were found to be approximately constant over some burning regimes (e.g., CO2 yield over the flaming regime) while others displayed highly transient behaviour (e.g., CO yield was found to be burning regime dependent). Results from upholstered furniture scale experiments, including HRR and emission yields, are commonly used in various engineering applications; this study lends insight into the variability that can be observed for such data and the implications in applying this data in further analysis. [ABSTRACT FROM AUTHOR]

In this manuscript, the UiO-66-NH2(Zr) (MOFs) was adopted to modify ammonium polyphosphate (APP), and the novel synergistic integrated flame retardant system (APP@MOFs) was formed. The flame retardants were incorporated to the thermoplastic polyurethanes (TPU) matrix, and the effects of APP@MOFs on reducing flammability of thermoplastic polyurethanes were compared and investigated. The results show that the flame retardant and smoke suppression performances of TPU/APP@MOFs composites are improved significantly. The pHRR, THR, SPR, TSP, YCO, and YCO2 of TPU/APP@MOFs composites decreased by 75.76%, 86.19%, 69.74%, 86.34%, 57.14%, and 76.37% in comparison with pure TPU. Furthermore, the char residues increased from 0.11 (pure TPU) to 32.3% (TPU/APP@MOFs composites). Generally, the APP@MOFs have great effect on improving the flame retardant and smoke suppression performances of TPU due to the catalytic carbonization and dilution effects of APP, the synergistic and catalysis effects of MOFs. Through the char structure analysis, the mechanism of the TPU/APP@MOFs composites during the combustion processes was also investigated and proposed. [ABSTRACT FROM AUTHOR]

This paper tackles the influence of the functionalization of polystyrene and graphene oxide (GO) composites on the flammability characteristics. A microscale combustion calorimeter (MCC) was used to experimentally determine the heat release capacity (HRC), the specific heat release rate (HRR) and the total heat released (THR). Neural models were designed that correlate the THR with a number of parameters related to the composition and type of flame retardant used, the heating rate, the amount of residue, the HRC, the peak heat release rate (PHRR), the temperature at the peak pyrolysis rate (TPHRR) and the time elapsed until the occurrence of the peak heat release rate (Time). The best results in the training, validation and testing stages were achieved with the neural model with 9 neurons in the input layer, 40 neurons in the hidden layer and one neuron in the output layer. This model was incorporated into an optimization procedure, based on a genetic algorithm, to establish the values of the input parameters used in the training of the neural networks, in order to generate a minimum THR value, which is the output parameter. Since the synthesis of polystyrene particles with different GO concentrations is costly, this research helps to reduce the number of experimental tests and allows to determine the best GO concentration by means of neural models and genetic algorithms. [ABSTRACT FROM AUTHOR]

Determining the structure and fuel load is key to know the flammability of vegetation in the Mediterranean Basin where forest fires are frequent. Determine which plant structural variable is best related to living and dead fuel to develop allometric equations in nine species in the Western Mediterranean Basin. In the east of the Iberian Peninsula (Valencia Province), we measured four structural variables (basal stem diameter, height, maximum diameter and perpendicular diameter) that were related, by means of allometric equations, to the living and dead fuel separated into different size classes. We also analyze fuel changes across developmental states of the studied species, and the vertical distribution of dead fuel. General equations that consider all development states can be used to determine living fuel. However to obtain dead fuel, we recommend using specific equations for each development state and fuel fraction for better accuracy. The basal stem diameter was the best structural variable in almost all cases for estimating fuel in the studied species. Dead fuel load throughout species' ontological development is a key factor to manage Mediterranean plant communities. [ABSTRACT FROM AUTHOR]

Cotton fabrics have high hydrophilicity and low limiting oxygen index (LOI) value, so they are susceptible to fires and bacterial growth, which endanger people's lives and property and limit their further application. To solve the issue, the prepared green flame retardant β-cyclodextrin phosphate ammonium salt (β-CPAS) was first used to prepare flame retardant cotton fabric, which was then treated with hydrophobic agent phosphorylated hexadecanol (HP) to obtain flame retardant and hydrophobic cotton fabrics (FR-H-cotton) by the traditional dip-dry-cure technique. Fourier transforms infrared spectroscopy showed that β-CPAS and HP were covalently bonded to the cotton sample by a P–O–C bond. The treated cotton was self-extinguished under a vertical flame and had an LOI value of up to 31%. Cone calorimeter analysis showed that both the total heat release rate and peak heat release rate of treated cotton were decreased by about 80% than the control sample. Furthermore, the treated samples have excellent hydrophobicity and self-cleaning capabilities because of the presence of long-chain hexadecanol. Interestingly, FR-H-cotton remained excellent flame retardant and hydrophobic properties after 50 laundering cycles. This green and multifunctional cotton fabric has excellent potential for future market applications. [ABSTRACT FROM AUTHOR]

The poor EMI shielding ability, limited UV resistance, and weak interfacial adhesion have restricted the use of Ultra-high molecular weight polyethylene (UHMWPE) fabric in ballistic, aviation, and other applications. To overcome these drawbacks, the present study proposes an electroless composite coating (NiP/MWCNT) on UHMWPE fabric surface with different weight propositions of MWCNTs (1 mg/L, 2 mg/L, and 3 mg/L). Comparative analysis in terms of morphology, surface roughness, functional groups, UV absorption, phase structure, surface energy, flammability, tensile load, peeling load, and EMI shielding was carried out to understand the influence of MWCNTs concentration in the NiP/MWCNT composite coating. Morphological analysis revealed that when the concentration of MWCNT increases, the nodular structure changes and the coating structure turns coarser. In addition, UV absorption, surface roughness, and crystal size increased and the burning rate during the flammability test decreased. Fabric tensile test and peel test results revealed improvements in breaking load and peeling load with higher MWCNTs concentration. In the X band frequency range, NiP/MWCNT composite coating exhibited higher shielding effectiveness (SET = 64.10 dB) for a lower coating thickness of 0.033 mm compared to NiP coating (SET = 42.25 dB) with a higher coating thickness of 0.038 mm. This article further details the EMI shielding, surface energy, single yarn tensile test, and the peeling load of NiP/MWCNT composite-coated UHMWPE fabrics. [ABSTRACT FROM AUTHOR]

Lithium metal batteries (LMBs) show great promise for achieving energy densities over 400 Wh·kg−1. However, highly flammable organic electrolytes are a long-lasting problem that triggers safety hazards and hinders the commercial application of LMBs. Here, a nonflammable diluted highly concentrated electrolyte (DHCE) with ethoxy(pentafluoro)cyclotriphosphazene (PFPN) as a diluent is developed to simultaneously achieve high safety and cycling stability of high-voltage LMBs. The optimal DHCE not only ensures reversible Li deposition/dissolution behavior with a superior average Coulombic efficiency (CE) over 99.1% on lithium metal anode (LMA), but also suppresses side reactions and stress crack on the LiCoO2 (LCO) under high cut-off voltage. The newly developed DHCE exhibits high thermal stability, showing complete nonflammability and reduced heat generation between the electrolyte and delithiated LCO/cycled LMA. This work offers an opportunity for rational designing nonflammable electrolytes toward high-voltage and safe LMBs. [ABSTRACT FROM AUTHOR]

To improve the flame retardancy of cotton fabrics, a non-halogen and non-formaldehyde polymeric flame retardant (ACAPOC) was synthesized by a solvent-free method. ACAPOC was grafted onto cellulose, and the resulting –N–P(=O)–O–C bonds displayed p-π conjugation, hydrolysis resistance, and greater stability than P–O–C covalent bonds. A mechanistic study showed that ACAPOC affected the thermal degradation pathway of cotton fabrics, which promoted fibers to dehydrate into carbon by generating phosphoric acid or polymetaphosphoric acid through thermal decomposition, interfering with the combustion process. In addition, the non-combustible gases produced by decomposition also diluted the combustible gases, which comprehensively affected the combustion heat cycle. ACAPOC had unobvious effect on crystal structure and surface morphology of cotton fabrics, but greatly reduced the combustion efficiency. ACAPOC-25% underwent 50 LCs in conformity to AATCC 61-2013 3A standard, which can be considered as durable flame-retardant cotton fabrics. Moreover, damage to physical properties barely affected practical application. Taken as a whole, ACAPOC is a low-cost, easy-to-synthesize and efficient flame retardant for cotton fabrics, which may also be applied to other materials such as synthetic fibers. [ABSTRACT FROM AUTHOR]

The inherent flammability of polymeric materials poses a potential threat to life and the environment. From a perspective of material renewability and environmental concern, some phosphorus-rich biomass compounds have been considered as effective replacements for conventional intumescent-based flame retardants. In this work, with the aim of suppressing the potential fire hazard of highly flammable polypropylene in a sustainable strategy, a green and facile method was proposed to synthesize ZIF-67 and further used to synergistically improve the performance of phytic acid-based intumescent flame retardants. Diverging from conventional solvothermal synthesis strategies, ZIF-67 was directly prepared with polymer matrix via a solvent-free reactive extrusion method with a notable space time yield. The reaction-to-fire properties were comprehensively investigated under forced combustion bench-scale fire conditions using a cone calorimeter with an external heat flux of 50 kW m−2. It was found that flame retardancy behaviors remain competitive when replacing 10 mass% of expandable graphite with phytic acid component. With the addition of ZIF-67, the heat release (53% reduction), smoke production (22% reduction), char structure stability (35% increment), and specific extinction area (19% reduction) behaviors were further improved due to the development of compact phospho-carbonaceous networks during combustion. Considering these excellent synergistic improvements, it provides a new potential direction to efficiently fabricate biomass-based flame retardants. [ABSTRACT FROM AUTHOR]

Increased wildfire activity has raised concerns among communities about how to assess and prepare for this threat. There is a need for wildfire hazard assessment approaches that capture local variability to inform decisions, produce results understood by the public, and are updatable in a timely manner. We modified an existing approach to assess decadal wildfire hazards based primarily on ember dispersal and wildfire proximity, referencing landscape changes from 1984 through 2014. Our modifications created a categorical flammability hazard scheme, rather than dichotomous, and integrated wildfire exposure results across spatial scales. We used remote sensed land cover from four historical decadal points to create flammability hazard and wildfire exposure maps for three arctic communities (Anchorage and Fairbanks, Alaska and Whitehorse, Yukon). Within the Fairbanks study area, we compared 2014 flammability hazard, wildfire exposure, and FlamMap burn probabilities among burned (2014–2023) and unburned areas. Unlike burn probabilities, there were significantly higher in exposure values among burned and unburned locations (Wilcoxon; p < 0.001) and exposure rose as flammability hazard classes increased (Kruskal–Wallis; p < 0.001). Very high flammability hazard class supported 75% of burned areas and burns tended to occur in areas with 60% exposure or greater. Areas with high exposure values are more prone to burn and thus desirable for mitigation actions. By working with wildfire practitioners and communities, we created a tool that rapidly assesses wildfire hazards and is easily modified to help identify and prioritize mitigation activities. [ABSTRACT FROM AUTHOR]

At present, most of the previous work focused on the effects of crown bulk density, crown base height, and wind on the initiation and behaviors of crown fire using tree branches. However, very few investigations have been carried out related to the initiation and behaviors of crown fire using a real tree considering moisture content, crown height and tree flower. In this paper, a series of burning experiments are carried out using real trees to investigate the effects of moisture content, crown height and tree flower on initiation conditions from surface fire to crown fire and crown fire behaviors. The variables of two crown heights (1.0 m, 1.5 m), three crown moisture contents (45 ± 2%, 55 ± 2%, 65 ± 2%) and tree flowers are selected. The main conclusions are as follows: when the tree has the higher crown base height and the larger moisture content, the crown fire initiation success from surface fire decreases, while the existence of tree flowers tends to lead to initiation success of crown fire. The critical fireline intensity can be used to determine the initiation of crown fire from surface fire for conditions with the absence of tree flowers, whereas the critical value can not be applied to cases with the existence of tree flowers. Moreover, the lower moisture content and higher crown height are, the maximum values of the flame height, fire plume temperature, and radiation heat flux of crown fire are larger. Besides, when the tree is covered with tree flowers, the flame height, fire plume temperature, and radiation heat flux of crown fire increase significantly due to the increases of fuel load and flammability. This work can not only provide theoretical basis for crown fire, but also supply technical guidance for the prevention and extinguishment of crown fire. [ABSTRACT FROM AUTHOR]

Context: Quantifying spatial and temporal variations in landscape flammability is important for implementing ecologically desirable prescribed burns and gauging the level of fire risk across a landscape. Yet there is a paucity of models that provide adequate spatial detail about landscape flammability for these purposes. Objectives: Our aim was to quantify spatial and temporal variations in ignitability across a forested landscape. We asked: (1) How do fuel moisture and meteorological variables interact to affect ignitability? (2) Do fuel moisture thresholds for ignition vary across a gradient of forest types? (3) How does the spatial connectivity of ignitable fuel vary over time? (4) How could an ignitability model be used to inform fire management decision-making? Methods: We conducted field-based ignition tests with flaming firebrands over three fire seasons. Ignitions were attempted across a range of moisture and meteorological conditions at 15 sites in eucalypt forest in south-eastern Australia. Structural equation modelling and generalized linear models were used to quantify relationships between ignitability, aridity, fuel moisture and weather. Results: The strongest predictors of ignitability were the moisture content of dead near surface fine fuel and in-forest vapour pressure deficit. Ignition thresholds for both varied across an aridity gradient. Dense forests (i.e., wet and damp eucalypt forests) needed drier fuel and drier in-forest atmospheric conditions to ignite than sparser forests (i.e., shrubby foothill forest). Conclusion: Our modelling of ignitability could inform fire planning in south-eastern Australia and the methodology could be applied elsewhere to develop similar models for other regions. Days with consistently high ignitability across the landscape are more conducive to the development of large wildfires whereas days when ignitability is spatially variable are more suitable for prescribed burning. [ABSTRACT FROM AUTHOR]

In this present investigation, a new attempt was made to produce sustainable polyester-based biocomposites using Lansium parasiticum fruit shell powder and hemp chopped fibre. The main objectives of this investigation were developing biocomposite and studying its mechanical, wear, water absorption and flammability properties. The powder was produced from waste fruit shell via ball milling process whereas the fibre was used in as-received form. The biocomposites are prepared using a hand layup method where post-curing is applied at 110 °C at the end of the process. The results revealed that the addition of fibre and filler improved the mechanical properties. A maximum tensile and flexural strength of 98 MPa and 143 MPa were noted for composite having 3 vol% filler and 40 vol% of fibre. Similarly, the addition of filler into the resin reduced the wear coefficient as well as wear loss. A lowest sp. wear rate of 0.009 mm3/Nm was recorded for composite made with 5 vol% of filler. But the water absorption and flammability were found to be affected marginally upon cellulosic fibre and filler addition. Nonetheless, they are in acceptable range indicating better hydrophobicity and low flammability. As a verdict, the combination of hemp fibre and Lansium parasiticum fruit shell powder along with polyester resin could be a noteworthy combination to form biocomposites with less cost, more eco-friendly and sustainable and circular economy concerns. Moreover, this practice could create a habit of producing sustainable eco-friendly products from waste, thus reducing the severity of solid waste accumulation. These new generation waste-derived biocomposites could be used as functional working material in applications starting from domestic to high performance engineering sectors. [ABSTRACT FROM AUTHOR]

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A series of pentaerythritol derived flame retardant additives (FRs labeled FR1, FR2, FR3, and FR4) were synthesized and blended with thermoplastic polyurethane (TPU) to enhance its flame retardancy. The chemical structures of the FRs were established by FTIR, 1H, 13C and 31P NMR spectroscopy. The flammability of the TPU blends was analyzed through UL-94 vertical burning and limiting oxygen index (LOI) test. It is found that for FR4-TPU blends with 2% of phosphorus content, the LOI value reached up to 31.2%, and no melt dripping with a V-0 rating was obtained by UL-94, indicating its superior flame retardant properties. Thermogravimetric analysis (TGA) of TPU blends showed that the char yield increases from 3.9% in neat TPU to 20% with the addition of 2% of FR3 in TPU. Based on findings from scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), a possible mechanism for the flame retardant property of blends has been proposed. The improved flame retardant properties of TPU blends can be attributed to the formation of a continuous and highly entangled char. This work provides a suitable approach for synthesizing promising phosphorus-based flame retardants from readily available raw materials that can be used to enhance the flame retardancy of TPU. [ABSTRACT FROM AUTHOR]

In this work, we employed a two-step modification process to improve the properties of 2D bimetallic nanoplates M(OH)(OCH3) (M = Co, Ni), which were recently proven as a promising "nano-flame retardant". The nanoplates were in situ modified with metal-organic framework ZIF-67 first and then silanized with a coupling agent APTES. Epoxy resin (EP) nanocomposites were fabricated using the functionalized M(OH)(OCH3). We investigated the performance of the nanocomposites in flame retardance and thermal stability. The results showed that 3% of APTES@ZIF-67@M(OH)(OCH3) gave the EP nanocomposite the V-1 rating in UL-94 test and the highest limited oxygen index of 27.6%. Moreover, the pHRR value of EP/APTES@ZIF-67@M 3% was reduced by 20.0% and 9.6%, respectively, compared to neat EP and EP/ZIF-67@M 3%. Regarding the mechanical properties, the Tensile properties and energy storage modulus of EP nanocomposite were both improved with 3% of APTES@ZIF-67@M(OH)(OCH3). The GC-MS test results revealed that the functionalized M(OH)(OCH3) significantly increased the cross-linking propensity of the EP matrix upon combustion, leading to the formation of a dense char layer. This study demonstrates the great potential of M(OH)(OCH3) as a highly efficient "nano-flame retardant" with tunable functionality. [ABSTRACT FROM AUTHOR]

The paper describes the preparation of polyamide 6 with reduced flammability by anionic in situ polymerization of ε-caprolactam in the presence of flame retardants, a method not described in the literature. Selected inorganic and brominated organic flame retardants were characterized by thermogravimetric analysis. Polymerization tests were used to test the compatibility of flame retardants with the components of the initiation system of anionic polymerization. Based on their results, polyamide plates for the preparation of test specimens were prepared by the method of polymerization casting in a mold. The content of water-extractable portions did not exceed 3%, i.e., the conversion of monomer into polymer took place to a high degree. The presence of flame retardants both inorganic and brominated organic in the polymer matrix did not affect the thermal stability, the content of the crystalline phase and also the mechanical properties. Samples containing brominated organic flame retarders were classified as V-0 according to the UL94 methodology. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is a versatile polymer with numerous applications that has undergone substantial changes in recent years, focusing on the demand for next-generation polymers. This article provides a comprehensive review of recent research in PP and its advanced functional applications. The chronological development and fundamentals of PP are mentioned. Notably, the incorporation of nanomaterial like graphene, MXene, nano-clay, borophane, silver nanoparticles, etc., with PP for advanced applications has been tabulated with their key features and challenges. The article also conducts a detailed analysis of advancements and research gaps within three key forms of PP: fiber, membrane, and matrix. The versatile applications of PP across sectors like biomedical, automotive, aerospace, and air/water filtration are highlighted. However, challenges such as limited UV resistance, bonding issues, and flammability are noted. The study emphasizes the promising potential of PP while addressing unresolved concerns, with the goal of guiding future research and promoting innovation in polymer applications. [ABSTRACT FROM AUTHOR]

In this study, a DOPO-based reactive flame retardant (DRFR) was synthesized and used as the second diphenol structure for preparation of flame-retardant rigid polyurethane foam (FR-RPUF). DRFR, as a phosphorus/nitrogen-containing diphenol, was prepared from 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), 4-hydroxy benzaldehyde, and benzidine. FR-RPUF was synthesized from polyether polyol (DaltoFoam TA® 14066) as the first hydroxyl-rich structure, DRFR as the second diphenol, and 4,4′-diphenylmethane diisocyanate through the one-pot method. For comparison, a pure rigid polyurethane foam (pure RPUF) was also synthesized without DRFR. The thermal stability of pure RPUF and FR-RPUFs was investigated by using thermogravimetric analysis (TGA). According to thermogravimetric analysis results, the temperature at 5 mass% loss (T5%) increased from 222 to 238 °C for sample containing 2 mass% of DRFR. Also, the char residue at 700 °C was enhanced by introducing DRFR. Flame retardancy and burning behavior were determined by the limiting oxygen index (LOI) and vertical burning test (UL-94). The LOI value of FR-RPUF sample containing 3 mass% DRFR achieved 21.5%, and the UL-94 test improved from no rating for pure RPUF to V-1 rating for FR-RPUFs. Compared with the pure RPUF, the resultant FR-RPUFs indicated better fire resistance and thermal stability. The dynamical mechanical thermal analysis results revealed that the storage modulus for FR-RPUFs is higher than pure RPUF, which attributed to the good interaction between DRFR and PU matrix. [ABSTRACT FROM AUTHOR]

This work aims to improve the thermal stability and flame retardancy of cotton fabrics treated just by a single SiO2, a single B2O3 and their binary composite sol–gel systems. Tetraethyl orthosilicate (TEOS) and tributyl borate were used as precursors. The sols were coated onto cotton fabrics via dipping-baking processes. Techniques including Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), limiting oxygen index (LOI) and vertical burning test (VBT) were used to investigate the surface functional groups, elemental compositions, crystal structures, surface morphologies, elemental contents, thermal stability and flame retardancy levels of original and sols-treated cotton fabrics, respectively. The results show that the sols converted gel coatings are successfully deposited on the cotton fabric surfaces. SiO2-B2O3 sol finishing cotton fabric shows the best flame retardancy. It shows the highest char residue rate (43.82%), the highest LOI (25.7%) and ΔLOI/Δm (7.0%/g), the lowest after-flame time (10.0 s) and after-glow time (0.0 s without a smoldering process), a relatively complete and continuous char residue after a VBT. The SiO2 and B2O3 sol–gel systems play more synergistic effects than competitive effects in flame retarding a cotton fabric. A SiO2 gel shows effects of a high melting point, a structural support and dimensional stability, while a B2O3 gel shows a fusing capability and a longer pyrolysis process. [ABSTRACT FROM AUTHOR]

Acrylonitrile–butadiene–styrene (ABS) composites with less smoke and toxicity hazards (e.g., HCN and NOx) emission are highly demanded. As a common smoke suppressant, zinc hydroxystannate (ZHS) has been used in various polymers, while the high content, special cube shape and agglomeration restrict its development. To solve these problems, MXene (Ti3C2Tx) nanosheets were utilized to wrap ZHS nanoparticles (Ti3C2Tx-PDA-ZHS) to improve the dispersion and compatibility of ZHS nanoparticles in ABS, in which polydopamine (PDA) was used as a binder to combine ZHS and MXene nanosheets. Accordingly, the prepared ABS/Ti3C2Tx-PDA-ZHS nanocomposites showed the enhanced properties: (1) ABS/Ti3C2Tx-PDA-ZHS exhibited a 69.7% increase in elongation at break compared to ABS/ZHS at a 2 mass% loading. (2) Owing to the synergistic effect of MXene and ZHS, Ti3C2Tx-PDA-ZHS provided excellent inhibition on heat and toxic gas release during combustion (a reduction of approximately 17.5%, 34.5%, 19.1% and 20.0% of peak heat release rate, HCN, NO and NO2, respectively). (3) The smoke density decreased from 525.6 for neat ABS to 423.2 for ABS/Ti3C2Tx-PDA-ZHS with a reduction of 19.5%, and the light transmittance of ABS/Ti3C2Tx-PDA-ZHS (37.7%) was much higher than that of pure ABS (21.2%) at 240 s. Therefore, Ti3C2Tx-PDA-ZHS showed a great enhancement in flammability, toxicity and smoke release reduction of ABS, potentially overcoming the weakness with improved diversity in future applications. [ABSTRACT FROM AUTHOR]

Natural fibre-based nanocomposite is a revolutionary substance developed in the past few years that is employed extensively in constructive and dynamic sectors due to its excellent strength relative to weight proportion and lightweight. The present investigation looked at how silicon nanoparticles affected the polypropylene (PP)/jute fibre's moisture absorption, mechanical properties, flammability, and dynamic mechanical features. Injection moulding was used to create composite materials made from PP, jute fibre, and silicon. The outcomes showed that increasing the weight of nano silicon di oxide (SiO2) nanoparticles up to 6% enhanced the modulus of elasticity (2100 MPa), tension strength (38.24 MPa), and elongation at breakage (1.67%) of hybrids. The bending strength and modulus of clean PP/jute were 34.19 MPa and 2160 MPa, respectively, while the bending strength and modulus of PP/jute/SiO2 were 51.78 MPa and 2780 MPa, respectively, demonstrating a 28.18% increase in bending strength. With increased nanoparticle loading, it was additionally demonstrated that water uptake (8.9%) and swollen thickness (2.01%) have significantly decreased. NanoSiO2 was added to composites to enhance their dynamic mechanical (loss and storage modulus of 4.92 & 12.80 MPa) behavior and fire characteristics (17 mm/min combustion rate, char residue of 29%). The 6 wt.% of SiO2 nanoparticles that exist in the jute fibre and PP specimens have not been exfoliated, so the manner in which they disperse has to be improved (2Ѳ = 2.32º, d-spacing of 39.01 nm and intercorrelation of 23.41%), according to X-ray diffraction (XRD) examinations. It is asserted that the char barrier's durability is significantly influenced by the chemical mixture's makeup and pattern of dispersion. The creation of char shields with higher nanosilicon dioxide content prevents burning and necessitates higher temperatures for disintegration. Graphical abstract of Nano SiO2/Jute Based Hybrid Polypropylene composites [ABSTRACT FROM AUTHOR]

Reducing the flammability of kapok fiber (KF) is an important strategy to increase its applicability. In this work, the phosphorylation of KF with ammonium dihydrogen phosphate (ADP) was used to reduce its flammability, the conditions of phosphorylation reaction were studied in detail, and the chemical groups, crystalline structure, thermal stability, heat release capability, flammability and charring ability of phosphorylated KF were analyzed. KF showed significantly higher phosphorylation level than cotton, and its phosphorylation greatly depended on ADP and urea dosage, reaction temperature and time, and pH. Urea addition, pH 6, 150 ℃ and 1 h rendered high phosphorylation with acceptable whiteness. Phosphorylated KF exhibited good char-forming, low heat release and excellent flame retardant performances during thermal degradation and combustion as evidenced by thermogravimetric, microcalorimetric, vertical combustion and combustion residue morphology analyses. The residue rate of phosphorylated KF subjected to thermal degradation exceeded 50% in nitrogen, and 25% in air. This investigation demonstrates that phosphorylated KF is an intrinsically flame retardant material. [ABSTRACT FROM AUTHOR]

The influence of particle size on the flammability and explosion severity has been widely demonstrated for coals along the years: the thinner the particle size, the more flammable is the dust and more severe are the explosions. Later, the increase on the use of biomass led to using the same resources and techniques for both groups of materials, considering them similar enough. However, there are basic differences between biomass and coal dust particles that leads to different behaviours when focusing on industrial fire safety. This difference is the starting point of this review, where a study on the existing knowledge in relation to the size and shape of biomass dust is presented. The methodologies and parameters used to determine particle size are described and discussed, showing the inconvenience of using only one parameter (d50) to describe dust, as well as the need of a standardized methodology to homogenise the results. The biomass data gathered from scientific literature and the following analysis carried out has also highlighted the importance of identifying samples in an accurate way and the strong necessity of further research on these materials and on the interdependence between particle size and the experimental procedures for flammability and explosibility properties. [ABSTRACT FROM AUTHOR]

Quasi solid-state succinonitrile (SN)-based polymer electrolytes have emerged for lithium-metal batteries due to their excellent ion-conductivity at room temperature, wide electrochemical stability window (ESW, usually >5 V). However, the practical application of these solid SN-based polymer electrolytes is hampered by the flammability and the inherent instability of SN to Li-metal anode. In this work, solid SN-based polymer electrolytes were prepared with succinonitrile, ethoxylated trimethylolpropane triacrylate (ETPTA), triethyl phosphate (TEP) and fluoroethylene carbonate for Li-metal battery via in situ polymerization method. The SN-based polymer electrolytes with 5 wt% triethyl phosphate and FEC showed good nonflammability, superior ion-conductivity as high as 1.01×10−3 S/cm, and wide ESW of 5.41 V. This SN-based polymer electrolyte also exhibited excellent interfacial compatibility to lithium metal anode. And it also delivered a high specific capacity of 156 mAh/g at 0.2 C at ambient temperature, and presented stable cycling at 1.0 C with a specific capacity retention of 98.4% after 1000 cycles. This work provides an alternative and simple strategy to realize the practical application of the solid-state SN-based polymer electrolyte. [ABSTRACT FROM AUTHOR]

In this paper, a single-component intumescent flame retardant di-(3-aminopropyltriethoxysilane) spirocyclic pentaerythritol diphosphate (PDAP) was synthesized, imparting flame retardancy to polylactic acid (PLA), which using melt blending process. The chemical structure and thermal stability of PDAP were characterized by test methods such as Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The fire retardancy of PLA/PDAP was evaluated by test methods such as limiting oxygen index (LOI) and vertical burning test (UL-94). The thermal stability of PLA/PDAP was studied by TGA and thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR). According to the results of laser Raman spectroscopy (LRS) and FTIR, the possible flame retardant mechanism of PLA/PDAP was discussed. With only 20 wt% addition of PDAP, PLA/PDAP could achieve 11.98% char residues at 800 °C. The LOI value of PLA/PDAP achieved 37%, UL-94 test reached V-0 rating. And higher fireproof performance with 62.1% reduced peak heat release rate (PHRR), 36.8% reduced total heat release rate (THR) and 19.5% reduced average effective combustion heat (av-EHC) value than PLA. The results show that PDAP has remarkable flame retardant effect on PLA, which provides an excellent research case for flame retardant modification of PLA plastic products. [ABSTRACT FROM AUTHOR]

In technical terms, wood is a natural composite material with a polymer matrix, reinforced with fibres made of uniaxially oriented longitudinal cells. Due to the ease of obtaining and relatively low technological requirements related to its processing, wood is a common material used for various types of construction materials. An experimental investigation was carried out to determine the evolution of the ignition sensitivity and the explosion of three types of softwood dusts. Two of those dusts come from conifers and one from a deciduous tree. Complete fire characteristic requires several parameters describing wood dust behaviour under fire conditions including heat release rate (HRR), ignition time, or fire growth index. To determine those parameters, a cone calorimeter was used. Explosion characteristic was tested for representative wood as a dust sample in 20-L spherical vessel. Minimum ignition energy (MIE) was tested on MINOR II apparatus, which is a modified Hartman's tube. Minimum ignition temperatures were tested with the use of layer ignition temperature apparatus and Godbert–Greenwald apparatus for minimum ignition temperature of a dust layer and dust cloud (MIT), respectively. Dust with the highest KST value, lowest MIE in the widest concentration range, and lowest MIT was pine wood dust. It also shows the shortest ignition time and a timespan between ignition and HRR peak. [ABSTRACT FROM AUTHOR]

In the current study, aluminum phytate (AlPt) is used with huntite–hydromagnesite (HH) in plasticized poly(lactic acid) (PLA) in order to improve the fire-retardant performance of the composite. The flame retardant, thermal, and mechanical properties of the composites are investigated using the limiting oxygen index (LOI), horizontal and vertical burning test (UL-94), mass loss calorimeter, thermogravimetric analysis, tensile, and impact tests. According to the test results, the fire-retardant performance of the composite was improved when HH and AlPt were used together. The highest LOI value (33.8) and UL-94 rating of V0 were achieved with the addition of 5 mass% AlPt in the presence of 55 mass% HH. Further, the addition of AlPt did not change the flammability properties. AlPt showed its adjuvant effect predominantly in the condensed phase via improved char formation with enhanced barrier properties. Tensile and impact strength reduced as the added amount of AlPt increased due to the hydrolytic degradation of PLA during the extrusion process. [ABSTRACT FROM AUTHOR]

With recent fires in ancient buildings such as Notre-Dame de Paris in France, Wanan Ancient Bridge in China, and the Cavallerizza Reale in Italy, it can be seen that aging wood buildings are more prone to fire and not easy to control once flame spreads. In this paper, the ignition of typical woods (Cypress and Fir in China) in ancient buildings was explored experimentally and theoretically by cone calorimeter under external heat flux (25, 35, and 50 kW m−2), and the measured ignition times were modeled by integration to create an ignition model. The results show that the fitted ignition temperature (Tig) equation can predict the ignition temperature of wood reasonably well. The theoretical ignition time curve calculated by the integral model agrees with the experimental value, which can be used for prediction of wood radiation ignition. This paper can assess the fire risk of wooden ancient buildings and provide important help for fire prevention and control in ancient buildings. [ABSTRACT FROM AUTHOR]

Polymers are widely employed in many areas, e.g. transport, packaging, electronic devices, etcetera. Among them, acrylonitrile–butadiene–styrene (ABS) is one of the most employed polymers due to its mechanical properties, its ease to mechanize and recyclability. Nevertheless, according to the fire properties, ABS behaviour is usually worse than other polymers, therefore, they have to be upgraded with flame retardant additives. To characterize the fire behaviour of a certain material is necessary to address several typology of tests, providing relevant properties such as thermal conductivity, flammability and heat released. However, researchers may not always be able to run all tests due to the lack of apparatus or samples. Therefore, it is necessary to seek bibliographic sources. As one might expect, for a given material, the property values should be similar, regardless of who performs the test. However, sometimes slightly different results are obtained, which may be due to different causes, such as differences in test set-up and in material composition/manufacture. These differences in properties may lead researcher to doubt which data to use. This paper presents the results of different types of tests using neat ABS polymer. Additionally, these results are compared with the data from literature, discussing the similarities/differences and offering a more comprehensive characterization of ABS. The laboratory techniques included in this work are: thermogravimetric analysis, differential scanning calorimetry, laser flash analysis, smoke density, cone calorimeter, fire propagation and flammability. [ABSTRACT FROM AUTHOR]

Cone calorimeter is widely used to study fire behaviour of materials employing small size samples. This equipment allows obtaining parameters such as time to ignition (TTI), heat of combustion, mass loss rate (MLR), or heat release rate (HRR) under different heat fluxes. Some studies have considered a linear fitting between MLR and HRR peaks and the incident heat flux. In accordance with this hypothesis, the computer model Fire Dynamics Simulator (FDS) has included a simple model to extrapolate burning rate data collected from a cone calorimeter test to the heat feedback occurring during a simulation. Nevertheless, deviation in the prediction of the HRR peaks at 75 kW m−2 of approximately 39.3% and of 37.1% for the first and second peak, respectively, were found. Therefore, this work presents a correlation between the incident heat flux and the global HRR per unit area curve, testing up to five different cables and several heat fluxes. To do so, some modifications of the FDS correlation are performed to consider the effect of the flame heat flux in the decomposition of the cables. Once experimental data are acquired, a computational analysis is carried out using FDS to achieve the flame heat flux in the samples. Additionally, this flame heat flux has also been obtained from the literature. As a conclusion, the addition of the flame heat flux to the cone calorimeter incident heat flux provides better predictions than the linear fitting methodology defined in the FDS Guide. Furthermore, this correction is checked with: (1) the example included in FDS guide, decreasing the HRR peaks errors from around 38% to around 25%; and (2) to seven different cables from the literature, decreasing the HRR peaks relative errors, as average, from 14.2 to 9.5% approximately. [ABSTRACT FROM AUTHOR]

Herein, various of silicone rubber foam (SRF) composites containing tri-metallic zinc-nickel-aluminum layered double hydroxides (ZnNiAl-LDH) were fabricated though a dehydrogenative foaming strategy. The chemical composition and structure of ZnNiAl-LDH were characterized by a series of measurements. The incorporated ZnNiAl-LDH filler exhibited good dispersion level in SRF matrix, and the SRF-LDH1 possessed a denser pore structure. Taking advantages of the lamellar structure and catalytic function of ZnNiAl-LDH, the most efficient improvements in mechanical, thermal stability, and flame retardancy properties were achieved for the SRF-LDH1 composite containing 1 wt% of LDH. Particularly, the SRF-LDH1 exhibited significantly increase in tensile strength (36.8 kPa), elongation at break (50.2%), compression stress (65.3 kPa), limiting oxygen index (28.6%), and UL-94 rating (V0) than the pristine SRF. In addition, the SRF-LDH1 showed significantly reductions in THR (37.9%) and TSP (30.4%), and the relevant time of TTI and TPHRR delayed about 2 times, as compared to the SRF. The present work affords a new approach to prepare silicone rubber foam composite with improved application performances. [ABSTRACT FROM AUTHOR]

Light-weight and fire safety are crucial requirements for fiber-reinforced polymer composites used in mainly the logistics sector. Phosphorus-based FR agents can be one of the effective solutions to improve the flame retardancy properties of highly flammable poly(butylene terephthalate) (PBT) and its composites reinforcing with various high-performance fibers. In this perspective, the purpose of this study was to see how microencapsulated red phosphorus (mRP) affected the flame retardancy of a chopped basalt fiber (BF)-reinforced PBT composite. The composite samples were manufactured with the constant amount of BF (20 mass%) and mRP concentrations ranging from 5 to 20% by mass. A synergistic study between the mRP (14 mass%) and a neat TiO2 (1 mass%) was also carried out. The TGA, cone calorimeter, LOI, and UL-94 V tests were used to characterize samples. Char residues of composites were analyzed via the ATR-FT-IR and SEM inspections. Test results released that the HRR values of PBT matrix and BF-reinforced PBT composite decrease while the char formation and the LOI values steadily increased with the incorporation of mRP. Remarkable decreases in fire performance parameters were observed between 23 and 55% while the highest residue (35.0%) were achieved with the mRP concentration of 20 mass%. The increment in LOI at about 50% and a V0 rating in the UL-94 V test were obtained when the added amount of mRP reached to 20 mass%. A synergism was seen between the mRP and TiO2 in the condensed phase considering the results of MLC test. [ABSTRACT FROM AUTHOR]

To alleviate the fire hazard of epoxy resin (EP), an efficient flame retardant (ADM) containing phosphophenanthrene and thiazole groups is synthesized and used as co-curing agent for 4,4′-diaminodiphenyl methane to prepare EP/ADM composites. EP/4 mass% ADM composites with phosphorus content of only 0.25 mass% reach UL-94 V-0 rating and the limiting oxygen index value is high to 35.8%. The results reveal that the peak heat release rate, total smoke production, and total heat release of EP/4 mass% ADM composites are reduced by 24%, 14.4% and 16.7%, respectively, in comparison with those of pure EP. The improvement in flame retardancy is mainly attributed to the decomposition of DOPO which produces HPO• and PO• to capture the reactive radicals in the gaseous phase. The thiazole group releases hindered amine groups and inactive gas with a dilution effect in the gaseous phase thus further enhancing the effect of the phosphophenanthrene group. Besides, ADM helps to increase the glass transition temperature (Tg) of EP/ADM composites, which is 176 °C for EP/4 mass% ADM composites, which is higher than the value (172 °C) of EP. [ABSTRACT FROM AUTHOR]

FTIR and Raman spectra of melaminium cyanoacetate have been recorded and analyzed. Band assignments are given based on the melamine and cyanoacetic acid molecules. The ring breathing vibrations of the triazine ring show frequency shift toward the high wavenumber side. This change is attributed to an increase in rigidity of the ring as a consequence of protonation and the formation of donor–acceptor types of hydrogen bonding interactions. Notably, this melaminium cyanoacetate salt also contributes to the efficient flame-retardant properties of polyurethane foam substrate as revealed by the flammability test and thermogravimetric analysis. [ABSTRACT FROM AUTHOR]