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In order to find an appropriate method to synthesize a new high-efficiency flame retardant for epoxy resin.

In this work, a flame retardant with heterocyclic groups, HOMP, was acquired after removing the obstacle from triazines which was not readily soluble. The molecular structure, thermal and flame retardant properties were fully characterized and analyzed. Also, the mechanism was researched through multi-methodologies. As well, the authors evaluated the effects of HOMP on mechanical properties.

The results suggested that HOMP helped extinguish the combustion of specimens and could reach an LOI value of 29.2% and the V0 level in the UL-94 test with a phosphorus content of only 0.6wt%. With respect to the mechanism, HOMP was a gas-phase flame retardant and helped generate a thicker carbon protective coating. However, for the mechanical properties, the addition of HOMP enhanced the compressibility, while the tensile strength decreased significantly.

The approach not only simplified the operations but also obtained HOMP with excellent flame retardant properties.

Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.

Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.

The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.

Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.

The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.

This paper aims to examine the fire retardant property potentials of cow horn ash particles (CHAp) bio-additive and aluminium trihydrate (AH), a traditional inorganic fire-retardant additive, respectively, in banana peduncle fibre (BPF) reinforced polyester composites. An attempt was made to comparatively analyse the fire retardant capacity potentials of CHAp, a bio-material waste that is readily available, at no cost, as a potential fire retardant material for composites manufacture with a conventional inorganic fire retardant additive (AH).

The fibre used in this research was derived from the banana peduncle. The matrix is unsaturated polyester. A scanning electron microscope was used to analyze the particle size of the carbonized CHAp. The composites were compounded using 0%, 2.5%, 5%, 7.5% and 10% of CHAp and AH, respectively. A cone calorimeter instrument was used in the analysis to obtain combustion information of CHAp and AH formulated polyester-BPF composites. Test samples were cut to the dimensions of 100 × 100 mm. All materials are conditioned at 23 ± 30 °C and the relative humidity of 50 ± 5% for 24 h before testing. The samples were wrapped with aluminium foil around the back and edges before placing the samples on the holder and then into the cone calorimeter. The samples were backed with a non-combustible insulating refractory material (brick). The samples were orientated horizontally and exposed to irradiances of 50 kW/m² at a temperature of approximately 6000 °C. The samples were pilot ignited and ran in triplicate; the average readings of the three runs were taken.

The results obtained from the analysis depicted similar fire retardant properties for formulations with CHAp and AH, respectively. Composites formulated with CHAp exhibited delayed ignition time of 25%, increased end of burning time of 14.24% and reduced total heat release rate of 9.07% for the developed composites. The developed BPF/CHAp/polyester composites yield composites with fire retardancy, which would find relevance in the engineering material industry.

CHAp, therefore, would suffice as an alternative to the inorganic, expensive and non-environmental friendly, conventional fire retardant additives used in composites manufacture.

The fire sector within the United Kingdom has identified a need to further develop their systematic use of academic literature and develop mechanisms to include academic knowledge to inform evidence-based policy and practice. By increasing knowledge exchange between the fire sector and academia, the ability to horizon scan and identify future relevant phenomena of interest to the fire sector will be achieved. Consequently, the evidence base and horizon scanning will increase the specificity of techniques, approaches and practices needed to continually improve the safety of the activities completed within the firefighting occupation, and it will also provide priority areas for investment and increase firefighter safety.

This technical paper primarily features an initial scoping review of academic and grey literature and an operational incident data review. This was completed to provide an initial and updated review of disciplines and areas of academia that are actively engaged in research relevant to the fire and rescue service. Consequently, this method sought to identify and examine the various disciplines of academia involved in fire research. This paper then uses that outcome to suggest a model of multidisciplinarity to inform the fire sector.

As a result of the scoping review, each academic discipline was identified and an initial review developed a predetermined set of key search terms. This was established through identifying the most frequently used fire-related terms within each discipline. This allowed for a comprehensive understanding of the breadth of activity and depth of complexity of fire related research within each discipline and an indicative set of key search terms to be developed. Recommendations are formulated to suggest next steps to routinely incorporate the academic knowledge base in the learning process of the fire and rescue services in the United Kingdom.

This paper provides an initial scoping map of academic literature and disciplines relevant to activities completed in the UK fire sector, which can be used to further develop the evidence base to inform the fire and rescue service of the United Kingdom. It also outlines possible mechanisms and a model to systematically facilitate knowledge exchange between academia and the fire sector by which knowledge exchange could further support the development of evidence-based policy and practice. The broad range of benefits of collaboration between the fire and rescue service and academia are explored.

This paper provides clear evidence as to why fire related research should have an increased priority status to inform the national fire and rescue services learning process and evidence for national policy and guidance development within the UK fire and rescue service. Additionally, recommendations are made to support the consideration of academic evidence in the systematic sector wide learning process.

Previously, the UK fire and rescue service had limited coordinated strategic engagement with academic disciplines to further develop their learning processes in order to produce an evidence base, which is cognisant of academic research to inform practice and guidance. This paper begins the narrowing of that gap by categorising academic literature relevant to fire research into clear disciplines, mapping these to an updated breadth of current activities undertaken by the fire and rescue service across the United Kingdom. The process also details a pilot of the proposed model to support knowledge exchange by producing an academically evidence-based submission to the National Fire Chiefs Council organisational learning process.

The potential for burn injuries arises from contact with a hot surface, flame, hot liquid and steam hazards. The purpose of this study is to develop the flame retardant acrylic and cotton blend textile finished with Enset Ventricosum pseudostem sap (EPS).

The two fabric was produced from (30% acrylic with 70% cotton) and (35% acrylic with 65% cotton) blend. The extracted sap was made alkaline and applied on two mordanted blend fabrics. The effect of blend ratio, the concentration of EPS and treatment time on flammability, Flame retardant properties of both the control and the treated fabrics were analyzed in terms of vertical flammability based on the design of the experiment software using central composite design. The air permeability and tensile strength of treated and controlled fabric were measured.

The blended fabrics at different blended ratios were flame retardant with an optimized result of burning time 2.902 min and 2.775 min and char length 6.442 cm and 7.332 cm in the warp and weft direction, respectively, at a concentration of 520 ml and time 33.588 min. There was a slight significant change in mechanical strengths and air permeability. The thermal degradation and the pyrolysis of the fabric samples were studied using thermogravimetric analysis and the chemical composition by Fourier-transform infrared spectroscopy abbreviated as Fourier-transform infrared spectroscopy. The wash durability of the treated fabric at different blend ratios was carried out for the optimized sample and the test result shows that the flame retardancy property is durable up to 15 washes.

Development of flame retardant cotton and acrylic blend textile fabric finish with ESP was studied; this work provides application of EPS for flame resistance which is optimized statically and successfully applied for a flame retardant property on cotton-acrylic blend fabric.

This paper aims to develop flame-retardant (FR) polyamide 12 (PA12) nanocomposite from regenerated powder via selective laser sintering (SLS), an additive manufacturing technique.

First, the morphology, processibility, thermal and mechanical properties of PA12 regenerated powder, consisting of 50 wt% new and 50 wt% recycled powder, as well as corresponding printed specimens, were evaluated to characterize the effects of previous SLS processing. Second, flame-retardant PA12 was developed by incorporating both single and binary halogen-free flame retardants into the regenerated powder.

It was found that the printed specimens from regenerated powder had much higher tensile and impact properties compared to specimens made from new powder, which is attributed to better particulate fusion and coalescence realized in higher temperature SLS printing. The effect of FRs on thermal, mechanical and flame retardant properties of the PA12 composites/nanocomposites was investigated systematically. It was found that the nanoclay, as a synergist, improved both flame-retardant and mechanical properties of PA12. UL94 standard rating of V-0 was achieved for the printed nanocomposite by incorporating 1 wt% nanoclay into 15 wt% phosphinates FR. Moreover, on average, the tensile and impact strength of the nanocomposite were increased by 26.13% and 17.09%, respectively, in XY, YZ and Z printing orientations as compared to the equivalent flame retardant composite with 20 wt% of the phosphinates FR.

This paper fulfills the need to develop flame retardant parts via SLS technology with waste feedstock. It also addresses the challenge of developing flame retardant materials without obviously compromising the mechanical properties by making use of the synergistic effect of nanoclay and organic phosphinates.

The purpose of this study is to predict the thermal protective performance (TPP) of flame-retardant fabric more economically using machine learning and analyze the factors affecting the TPP using model visualization.

A total of 13 machine learning models were trained by collecting 414 datasets of typical flame-retardant fabric from current literature. The optimal performance model was used for feature importance ranking and correlation variable analysis through model visualization.

Five models with better performance were screened, all of which showed R2 greater than 0.96 and root mean squared error less than 3.0. Heat map results revealed that the TPP of fabrics differed significantly under different types of thermal exposure. The effect of fabric weight was more apparent in the flame or low thermal radiation environment. The increase in fabric weight, fabric thickness, air gap width and relative humidity of the air gap improved the TPP of the fabric.

The findings suggested that the visual analysis method of machine learning can intuitively understand the change trend and range of second-degree burn time under the influence of multiple variables. The established models can be used to predict the TPP of fabrics, providing a reference for researchers to carry out relevant research.

The findings of this study contribute directional insights for optimizing the structure of thermal protective clothing, and introduce innovative perspectives and methodologies for advancing heat transfer modeling in thermal protective clothing.

Most of the industrial buildings which are designed to moderate loads are constructed using light gauge cold-formed steel (CFS) sections. Residual mechanical properties of CFS sections exposed to elevated temperature need to be investigated as it is necessary to predict the deterioration of elements to avoid failure of the structure or its elements. Also, it would be helpful to decide whether the structural elements need to be replaced or reused. The use of fire-resistant coatings in steel structures significantly reduces the cost of repairing structural elements and also the probability of collapse. This study investigates the effect of fire-resistant coating on post-fire residual mechanical properties of E350 steel grade.

In this study, an attempt has been made to evaluate the residual mechanical properties of E350 steel. A tensile coupon test was performed for the extracted specimens from the exposed CFS section to determine the mechanical properties. Four different fire-resistant coatings were selected and the sections were coated and heated as per ISO 834 fire temperature curve in the transient state for time durations of 30 minutes (821°C), 60 minutes (925°C), 90 minutes (986°C), and 120 minutes (1,029°C). After the exposure, all the coupon specimens were cooled by either ambient conditions (natural air) or water spraying before conducting the tension test on these specimens.

At 30 min exposure, the reduction in yield and ultimate strength of heated specimens was about 20 and 25% for air and water-cooled specimens compared with reference specimens. Specimens coated with vermiculite and perlite exhibited higher residual mechanical property up to 60 minutes than other coated specimens for both cooling conditions. Generally, water-cooled specimens had shown higher strength loss than air-cooled specimens. Specimens coated with vermiculite and perlite showed an excellent performance than other specimens coated with zinc and gypsum for all heating durations.

As CFS structures are widely used in construction practices, it is crucial to study the mechanical properties of CFS under post-fire conditions. This investigation provides detailed information about the physical and mechanical characteristics of E350 steel coated with different types of fire protection materials after exposure to elevated temperatures. An attempt has been made to improve the residual properties of CFS using the appropriate coatings. The outcome of the present study may enable the practicing engineers to select the appropriate coating for protecting and enhancing the service life of CFS structures under extreme fire conditions.

This paper aims to illustrate the growing role of drones in applications involving physical tasks.

Following a short introduction, this first provides a brief introduction to drone technology. It then describes and discusses products and applications involving physical tasks in agricultural and forestry, maritime rescue, firefighting and product delivery. Finally, brief conclusions are drawn.

Excluding military applications, drones were initially used primarily for image acquisition. Numerous different designs have since been developed with greatly varying wing configurations, payloads, flight duration, power sources and other features which are increasingly being used to conduct physical tasks. In the applications considered here drones are applying agrochemicals and dispersing crop and tree seeds; saving lives by deploying lifeboats and buoyancy aids; extinguishing fires in high-rise buildings and forests; and delivering groceries, food, mail, medicines and humanitarian aid, often in and to remote locations.

This study provides a detailed insight into selection of applications in which drones conduct physical tasks.

Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to improve the thermal insulation performance of polyethylene terephthalate (PET), the SiO₂ aerogel/PET composites slices and fibers were prepared, and the effects of the SiO₂ aerogel on the morphology, structure, crystallization property and thermal conductivity of the SiO₂ aerogel/PET composites slices and their fibers were systematically investigated.

The mass ratio of purified terephthalic acid and ethylene glycol was selected as 1:1.5, which was premixed with Sb₂O₃ and the corresponding mass of SiO₂ aerogel, and SiO₂ aerogel/PET composites were prepared by direct esterification and in-situ polymerization. The SiO₂ aerogel/PET composite fibers were prepared by melt-spinning method.

The results showed that the SiO₂ aerogel was uniformly dispersed in the PET matrix. The thermal insulation coefficient of PET was significantly reduced by the addition of SiO₂ aerogel, and the thermal conductivity of the 1.0 Wt.% SiO₂ aerogel/PET composites was reduced by 75.74 mW/(m · K) compared to the pure PET. The thermal conductivity of the 0.8 Wt.% SiO₂ aerogel/PET composite fiber was reduced by 46.06% compared to the pure PET fiber. The crystallinity and flame-retardant coefficient of the SiO₂ aerogel/PET composite fibers showed an increasing trend with the addition of SiO₂ aerogel.

The SiO₂ aerogel/PET composite slices and their fibers have good thermal insulation properties and exhibit good potential for application in the field of thermal insulation, such as warm clothes. In today’s society where the energy crisis is becoming increasingly serious, improving the thermal insulation performance of PET to reduce energy loss will be of great significance to alleviate the energy crisis.

In this study, SiO₂ aerogel/PET composite slices and their fibers were prepared by an in situ polymerization process, which solved the problem of difficult dispersion of nanoparticles in the matrix and the thermal conductivity of PET significantly reduced.