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High‐efficient flame retardants (ZrP‐DDM) were synthesized successfully via ion‐exchange method, using diaminodiphenylmethane (DDM) modified layered zirconium phosphate (α‐ZrP). Trace addition of ZrP‐DDM in epoxy resins (EP) can enhance the flame‐retardant, smoke‐inhibition, mechanical, and thermal stability properties of EP composites. As shown in the results, ZrP‐DDM exhibits a better synergistic effect than α‐ZrP, and the EP composites containing 0.5 wt% ZrP‐DDM (EP/0.5ZrP‐DDM) show excellent flame‐retardant and smoke‐inhibition properties. Especially, EP/0.5ZrP‐DDM possesses a limiting oxygen index (LOI) of 33.7% with UL94 V‐1 rating, while the EP composites containing 0.5 wt% ZrP (EP/0.5ZrP) has a LOI of 30.1% and fails to achieve the UL94 rating. Furthermore, the peak heat release rate (PHRR), total heat release rate (THR), and smoke density rating of EP/0.5ZrP‐DDM decrease by 10.2%, 3.7%, and 8.2% compared with EP/0.5ZrP. Based on condensed‐phase product analysis, EP/ZrP‐DDM sample provides a gas source for intumescent char layer, and produces a stable phosphorus‐rich crosslinking structures during combustion, thus decreasing the fire hazard of the composite material. Meanwhile, the introduction of ZrP‐DDM has a less impact on tensile strength of EP composites compared with α‐ZrP, suggesting the addition of ZrP‐DDM effectively enhances the compatibility with the EP matrix, thereby maintaining excellent mechanical properties of the EP matrix. [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]

In civil construction, one of the primary challenges associated with wood application is its high flammability and low durability during fires. Although chemical treatment with fire-retardant properties exists, they are expensive and of non-renewable origin. Tannin, a wood extractive, being a phenolic compound, holds promise for enhancing the thermal properties of wood. This study aimed to assess the efficacy of tannin as a fire retardant and compare it with a commercial product, as well as comparing different application techniques for these products. Wood samples from the Simarouba amara Aubl. species were utilized. Tannin and a commercial flame retardant were applied via immersion, vacuum impregnation, brushing, and a treatment of tannin incorporated into water-based wood varnish. Alongside the burning test performance, assessments of the wood's physical properties, such as colorimetry, thermal stability, and mass retention, were conducted. The application of tannin altered the wood's color and reduced the spread of fire; its presence significantly reduced the flame duration and maintained the wood's structural integrity. However, tannin retention was lower compared to commercial flame retardant, leading to reduced fire retardancy. Among the methods tested, immersion proved to be the most effective in enhancing the wood's resistance to flame contact. [ABSTRACT FROM AUTHOR]

This research study focused on the effect of adding boric acid to epoxy resin in order to obtain a composite material with improved properties and performance. To this end, a fine powder of boric acid (H3BO3) was introduced into epoxy resin in different amounts, i.e., 0.5 g, 1.0 g, and 1.5 g. As the matrix of the epoxy composites, styrene-modified epoxy resin based on bisphenol A (BPA) (Epidian 53) was used. It was cross-linked with two types of curing agents, i.e., an amine (ET) and a polyamide (PAC). The mechanical properties of the obtained epoxy composites (in terms of compressive strength, compressive modulus, and compressive strain) were determined at room temperature in order to assess the effect of the addition of boron acid and of the type of curing agent employed to cure the epoxy on these characteristics. Calorimetric measurements were made to highlight any changes in the glass transition temperature (Tg) as a result of the addition of boric acid to epoxy resin. Finally, flammability tests were performed on both Epidian 53/PAC and Epidian 53/ET epoxy composites to analyze their fire behavior and consequently establish the effectiveness of the selected additive as a flame retardant. [ABSTRACT FROM AUTHOR]

Polyurea (PUA) is widely used as a coating in construction, tunnels, bridges, and other fields because of its excellent performance. However, its combustion emits toxic gases and smoke, hindering escape and posing potential fatality risks. Enhancing the flame retardancy of PUA is crucial for safety and expanding its applications. The synthesis of two‐dimensional FePP nanosheets was reported in this paper, employing the solvothermal method, followed by the sequential growth of MoS2 and Ni‐MOF to establish a multilayer composite structure. The elemental composition and morphology of the synthesized FePP@MoS2@Ni‐MOF flame retardants were characterized and analyzed. The flame retardant properties of polyurea composites with varying amounts of FePP@MoS2@Ni‐MOF were investigated using Cone calorimeter tests. The results showed that the prepared flame retardant had good thermal stability and significantly improved fire safety properties. The PUA/FePP@MoS2@Ni‐MOF 3.0 composite exhibited notable improvements compared to pure PUA. Specifically, the peak heat release rate, total heat release rate and peak smoke production rate were reduced by 39.76%, 29.33% and 17.86%, respectively, while total smoke production and total CO production (COP) were reduced by 21.30% and 54.47%. This study provides new insights and experimental basis for the technological development of novel flame retardant coating materials. [ABSTRACT FROM AUTHOR]

The widespread industrial applications of thermoplastic polyurethane (TPU) are partially limited by its flammability. The design of high‐performance intumescent flame retardants (IFR) is of great significance for enhancing flame retardant (FR) performance of TPU. In this work, an IFR system consisting of ammonium polyphosphate (APP), double pentaerythritol (DPER), and zinc borate (ZB) is proposed. The optimized experimental parameters with 15 wt.% additive amount of FR, APP‐DPER weight ratio of 2.28:1 and 15.56 wt.% ZB content are regulated based on Box–Behnken design‐response surface methodology (BBD‐RSM) to obtain TPU/FR composite with superior limiting oxygen index value of 30.2%. Noticeably, the design efficiency of TPU/FR composite is significantly improved by utilizing BBD‐RSM. Results of vertical burning test show that the optimized TPU/FR composite passes UL 94 V‐0 rating and peak heat release rate is dramatically reduced from 1355.88 (neat TPU) to 201.01 KW/m2 through cone calorimeter test. In addition, scanning electron microscopy accompanied with Raman spectroscopy are conducted to characterize the morphology and composition of residual char for further exploring the FR mechanism of IFR system in TPU. The as‐prepared TPU/FR composite has provided new potential application in engineering fields. [ABSTRACT FROM AUTHOR]

In this study, process control factors such as dipping time, heat treatment time and curing conditions were optimized to prepare N-Si network sol–gel-based coatings on a cotton fabric. The dipping time was varied from 14 h to 30 min, the heat treatment time at ~90 °C was varied between no heating conditions to 15 h and the curing was performed at 165 °C. The microstructure of the coating was analyzed using low electron scanning microscopy (LV-SEM), while a compositional study of the coated substrate was carried out using FTIR and EDS techniques. From the thermal and combustion analysis of the coated samples using thermogravimetric and vertical flame test techniques, significant resistance to the degradation process was observed, particularly in the initial stages, in addition to the highest char residue for DI-0.5 h-15~32.93%. Similarly, for DI–5 h–RT, the peak degradation temperature was around ~372 °C, accompanied by a notable char residue of approximately 31.12%. The flame spread and burning rate profile further supported the findings; DI-0.5 h-15 and DI-5 h-RT had the lowest flame spread. [ABSTRACT FROM AUTHOR]

DL‐malic acid (DMA), as a recognized antioxidant inhibitor and chelating agent in the food and chemical industries, has good application prospects in coal fire prevention and control. This paper investigates the impact of a DMA solution on the surface properties and phase structure of coal through a range of analytical techniques, including electron microscope scanning, particle size analysis, and x‐ray diffraction. The thermal behavior characteristics of DMA‐treated coal were analyzed using thermogravimetric experiments. The results show that after adding malic acid, the particle size of coal sample is reduced, the sphericity and roundness are reduced, and the pore size is increased. The hydroxyapatite and calcite components in coal were dissolved and consumed, and the calcite components were gradually depleted with the increase of DMA concentration. The flocculent structure produced by the condensation of the crushing residue and broken small particles are attached to the internal pores of coal, which reduced the coal oxygen contact sites and increases the content of the sealed solution, resulting in the increase of the thermal characteristic temperature of the coal and the inhibition of the oxidation heat generation process. DMA has obvious inhibitory effect on fresh coal and oxidized coal, and the inhibitory effect is stronger on high‐temperature oxidized coal. Therefore, DMA can be effectively applied to the prevention and control of spontaneous combustion of residual coal in goaf. The research results provide a reference for the research of coal fire prevention technology and the preparation of environmentally friendly flame retardant materials. [ABSTRACT FROM AUTHOR]

In this research, a novel multifunctional flame retardant (DSF) was prepared through a reaction involving 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO), 4‐amino‐trifluorotoluene, and salicylaldehyde, was characterized by FTIR and 1H NMR, and was employed to prepare a multifunctional epoxy resin and cyanate ester resin copolymer (EPCE). A comprehensive investigation was conducted to assess the mechanical performance, dielectric properties, thermal behavior, and flame retardancy of EPCE composites. The results indicate that the EPCE composite with 8 wt% DSF (EPCE/8DSF) attained a LOI value of 28.1 vol% and a V‐0 rating. The EPCE/8DSF demonstrated a reduction of 25.8% in the peak heat release rate and a decrease of 25.6% in the total heat release in comparison with EPCE. In addition, the EPCE/8DSF composite demonstrated a decrease in both the dielectric constant and dielectric loss at 10 MHz, representing values of 3.58 and 0.00744, respectively. Furthermore, the incorporation of higher DSF content into the EPCE led to a decrease in mechanical properties. Highlights: A multifunctional flame retardant (DSF) was prepared by Kabachnik‐Fields reaction, and was used to fabricate multifunctional EPCE composites.EPCE/DSF composites have good flame retardancy.The prepared composites also have low dielectric constant and low dielectric loss. [ABSTRACT FROM AUTHOR]

In this work, biobased rigid polyurethane foams (PUFs) were developed with the aim of achieving thermal and fireproofing properties that can compete with those of the commercially available products. First, the synthesis of a biopolyol from a wood residue by means of a scaled-up process with suitable yield and reaction conditions was carried out. This biopolyol was able to substitute completely the synthetic polyols that are typically employed within a polyurethane formulation. Different formulations were developed to assess the effect of two flame retardants, namely, polyhedral oligomeric silsesquioxane (POSS) and amino polyphosphate (APP), in terms of their thermal properties and degradation and their fireproofing mechanism. The structure and the thermal degradation of the different formulations was evaluated via Fourier Transformed Infrared Spectroscopy (FTIR) and thermogravimetric analysis (TGA). Likewise, the performance of the different PUF formulations was studied and compared to that of an industrial PUF. From these results, it can be highlighted that the addition of the flame retardants into the formulation showed an improvement in the results of the UL-94 vertical burning test and the LOI. Moreover, the fireproofing performance of the biobased formulations was comparable to that of the industrial one. In addition to that, it can be remarked that the biobased formulations displayed an excellent performance as thermal insulators (0.02371–0.02149 W·m−1·K−1), which was even slightly higher than that of the industrial one. [ABSTRACT FROM AUTHOR]

Composites with excellent flame retardant and mechanical properties are in high demand in the aerospace and various industrial fields. Glass fiber (GF) reinforced polyimide (PI) composites (GFRPCs) were fabricated using a simple ball milling and hot pressing technique. The effect of GF content on the thermal stability, mechanical and flame retardant properties of composites has been systematically studied. The Rockwell hardness of GFRPCs increase with increasing GF content, while the compressive strength, impact strength and flexural strength initially show an increase followed by a decrease due to the excellent dispersibility of the fillers and the strong interfacial interaction between the one‐dimensional GF and PI matrix. Thermogravimetric analysis results show that the addition of GF with very low thermal conductivity and excellent temperature resistance can effectively improve the thermal stability of PI. Adding GF into PI can obviously improve the limiting oxygen index value. Moreover, as the GF content increased, the time to ignition of the composites prolonged while total heat release decreased. These findings suggest a viable solution for enhancing both the flame retardance and mechanical properties of PI‐based composites. Highlights: GFRPCs with high GF content fabricated via ball milling‐hot pressing method.Silane modified GF obviously improves the thermal stability of PI matrix.GFRPCs‐28 exhibits superior mechanical properties.An increases in time to ignition (TTI) and mass residual rate (MRR) of the GFRPCs was observed on adding GF. [ABSTRACT FROM AUTHOR]

In this study, the mechanical and flame‐retardant properties of flexible polyurethane foams (FPUF) were analyzed as a function of the type of flame retardant. FPUF containing equal amounts of two halogenated flame retardants (tris 2‐cloropropyl phosphate [TCPP] and phosphinyl alkyl phosphate ester) and three halogen‐free flame retardants (melamine, melamine cyanurate, and expandable graphite) were considered. The foaming properties of these samples were analyzed by studying the rise time and settling rate using cup foaming. Square foaming was used to analyze the mechanical properties, including density, elongation, tensile strength, and tear strength. In addition, Fourier‐transform infrared spectroscopy was performed, and flame retardancy was evaluated using a horizontal flame test and the limited oxygen index. A cone calorimeter test was also performed to evaluate the combustion characteristics. In FPUF containing the same ratio of flame retardant (15% of the total polyol), the properties of urethane foam blended with expandable graphite were improved; the tensile strength of this blend is 20% higher than that of samples containing melamine, and its peak heat release showed a 70% reduction compared to that of samples containing TCPP. These findings provide valuable reference information for developing flame retardants for fire safety FPUF in the near future. [ABSTRACT FROM AUTHOR]

The paper presents the results of research on the influence of the components of composition on the physicochemical properties of cross-linked poly(sodium acrylate)/sodium silicate hydrogels. The results of the rheological measurements showed that an increasing share of polyacrylate in the sample causes a shift of the cross-over point towards longer times and improves mechanical properties. In turn, increasing the share of sodium silicate has a positive effect on extending the fire insulation time (I). TG/DSC analysis indicated that if the sample contained more than 50 wt.% of polymer, the thermal decomposition was a three-stage process, while if the sample contained more water glass, the decomposition was two stage. UV-Vis measurements and SEM analysis confirmed, inter alia, that increasing the share of polyacrylate causes improvement of the optical parameters and homogeneity of the tested hydrogels. The presented results suggest that by controlling the share of the main components of the silicate–polymer hydrogels, it is possible to control their mechanical, optical and thermal properties. Multiplication of the layers or increasing their thickness improves their fire-retardant properties. [ABSTRACT FROM AUTHOR]

Linear low‐density polyethylene (LLDPE) and different concentrations (5‐20 wt%) of magnesium hydroxide (MAH) as a filler either with or without the addition of graphene nanoplatelets (GNPs) were peroxide cross‐linked using dicumyl peroxide as a cross‐linking agent in a twin‐screw extruder. The mechanical, thermal stability, flame retardancy, morphological, and rheological properties of the prepared samples were investigated. The mechanical properties of the peroxide cross‐linked LLDPE samples with higher MAH and GNP in the matrix were significantly improvement compared to neat LLDPE. This indicates that the addition of MAH and GNP to the peroxide cross‐linked LLDPE matrix could be suitable reinforcing fillers to achieve better and enhanced mechanical properties, particularly tensile strength. Conversely, a significant decrease in the elongation at break values was found for peroxide cross‐linked LLDPE samples compared to neat LLDPE. Similarly, results of thermogravimetric analysis revealed remarkable thermal stability enhancement in the peroxide cross‐linked LLDPE samples with higher MAH and GNP compared to neat LLDPE. The results from UL94 test demonstrated that the peroxide cross‐linked LLDPE samples comprising higher MAH with GNP exhibited improved V = 0 rating compared to poor no rating (NR) for neat LLDPE. Furthermore, the scanning electron microscope and digital images shown improved flame retardancy properties for these samples because of the formation of protective char layer on the sample surface. The complex viscosity for the peroxide cross‐linked LLDPE samples, at lower frequency, increased with increasing MAH loading and further addition of GNP compared to neat LLDPE. Highlights: Cross‐linked polyethylene with flame retardant (FR) and nanofiller were prepared.Effects of cross‐linking and FR on the final properties of the polymer were studied.20wt% FR with 3 phr nanofiller promoted the final properties of the polymer.Higher filler loading in the polymer improved flame retardancy and thermal stability.Combined effect of cross‐linking and FR has shown major improvement. [ABSTRACT FROM AUTHOR]

Graphene (GN) modified polystyrene (PS) was used to prepare flame retardant PS/GN thermal insulation material, and its mechanical properties and thermal properties were studied. The results show that KH-550 is successfully grafted onto the surface of GN. With the increase of GN content, the mechanical properties and heat resistance of PS/GN insulation materials gradually increase, and the thermal conductivity gradually decreases. When the content of GN is not more than 0.3%, the mechanical properties and heat resistance of PS/GN insulation material increase significantly, and the thermal conductivity increases little. The optimum content of GN is 0.3%, at this time, the compressive strength of PS/GN insulation material is increased by 37.2%, the initial degradation temperature is increased by 29 °C, the mass residue is increased by 0.7%, and the thermal conductivity is 0.037 1 W/(m·K). [ABSTRACT FROM AUTHOR]

In this study, rigid polyurethane foams modified with non-halogenated flame retardant were obtained. The foams were synthesized using two systems containing different blowing agents. In the first one, cyclopentane and water were used as a mixture of blowing agents, and in the second one, only water was used as a chemical blowing agent. The systems were modified with the additive phosphorus flame retardant Roflam F5. The obtained modified foams were tested for their flammability and basic properties, such as apparent density, closed-cell contents and analyses of the cell structures, thermal conductivity, mechanical properties, and water absorption. Increasing the content of Roflam F5 caused a decrease in temperature during the combustion of the material and extended the burning time. The addition of 1.0 wt.% phosphorus derived from Roflam F5 caused the modified rigid polyurethane foam to become a self-extinguishing material. The increase in the content of Roflam F5 caused a decrease in the total heat release and the maximum heat release rate during the pyrolysis combustion flow calorimetry. The foams with the highest content of flame retardant and foamed with a chemical-physical and chemical blowing agent had a lower total heat release by 19% and 11%, respectively, compared to reference foams. [ABSTRACT FROM AUTHOR]

Composite phase change materials commonly exhibit drawbacks, such as low thermal conductivity, flammability, and potential leakage. This study focuses on the development of a novel flame-retardant phase change material (RPCM). The material's characteristics and its application in the thermal management of lithium-ion batteries are investigated. Polyethylene glycol (PEG) serves as the medium for phase change; expanded graphite (EG) and multi-walled carbon nanotubes (MWCNT) are incorporated. Moreover, an intumescent flame retardant (IFR) system based on ammonium polyphosphate (APP) is constructed, aided by the inclusion of bio-based flame-retardant chitosan (CS) and barium phytate (PA-Ba), which can improve the flame retardancy of the material. Experimental results demonstrate that the RPCM, containing 15% IFR content, exhibits outstanding flame retardancy, achieving a V-0 flame retardant rating in vertical combustion tests. Moreover, the material exhibits excellent thermomechanical properties and thermal stability. Notably, the material's thermal conductivity is 558% higher than that of pure PEG. After 2C and 3C high-rate discharge cycles, the highest temperature reached by the battery module cooled with RPCM is 18.71 °C lower than that of natural air-cooling; the material significantly reduces the temperature difference within the module by 62.7%, which achieves efficient and safe thermal management. [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]

The properties of unconventional blends of crystallizable and thermo-cross-linkable polychloroprene (CR) with polybutadiene (BR) were investigated in this study. The compositions were prepared using the method of reactive processing and cross-linking in the presence of nano-sized zinc (nZn). The purpose of the research was to assess the efficacy of nano-zinc as a curing agent of polychloroprene and polybutadiene (CR/BR) composites and to obtain rubber goods characterized by increased flame resistance. The blends were filled with nano-silica (aerosil) and fillers of natural origin (chalcedonite or silitin). The cross-linking process was characterized by determining the kinetics curves, the equilibrium swelling, and the Mooney–Rivlin elasticity constants. The morphology of the vulcanizate surface was specified by scanning electron microscopy (SEM). The dynamic and mechanical properties, flammability, and toxicity of gaseous substances involved in thermal decomposition were determined. Mass changes and thermal effects were studied using simultaneous thermal analysis (STA). It was confirmed that nano-zinc is an efficient curing agent for the polychloroprene and polybutadiene compositions, with a satisfactory degree of cross-linking (αc = 0.10, CRI = 4.11 min−1), good mechanical strength (TSb = 5 MPa), satisfactory tear resistance (Ts = 2.9 N/mm), and very high flame resistance (OI = 30%, HRRmax = 283 kW/m2). Filled products could be used as non-combustible materials, confirming the low fire hazard (1/tflashover = 3.5–6.4 kW/m2∙s). The most effective filler of the tested composites was nano-sized silica. [ABSTRACT FROM AUTHOR]

A P/N containing flame retardant DOPO-QN was synthesized by a reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and 8-hydroxyquinoline (QN). Its chemical structure was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) like 1H, 13C, 31P NMR, and high-resolution mass spectrometry (HRMS) techniques. The synthesized DOPO-QN was employed as an additive type flame retardant in combination with clay nanomer 1.34TCN (NC) in diglycidyl ether of bisphenol A/4,4ʹ-diaminodiphenlsulfone (DGEBA/DDS) to synthesize epoxy thermosets. The fire behavior of synthesized epoxy thermosets was studied by UL-94, limiting oxygen index (LOI), and cone calorimeter tests. The EP/DOPO-QN (1.5%P)/NC sample passed the UL-94 test with a V-0 rating and LOI value of 26.5%. A decrease in peak heat released, carbon monoxide, and carbon dioxide emissions was observed in the cone calorimeter test. Thermogravimetric analysis (TGA) of epoxy thermosets showed an increase in thermal stability at a higher temperature range on the formation of nanocomposites. Also, a remarkable improvement in storage modulus was observed for the EP/DOPO-QN (1.5%P)/NC sample containing 2.0% NC in dynamic mechanical analysis (DMA). [ABSTRACT FROM AUTHOR]

To effectively reduce the fire hazard of flexible polyvinyl chloride (PVC), this study explored the synthesis of perovskite‐type copper hydroxystannate (CuSn(OH)6) microspheres by co‐precipitation method. Then an organic–inorganic hybrid microsphere (CuSn(OH)6@PZS) with core‐shell structure was fabricated by in situ coating with poly(cyclotriphosphazene‐co‐4,4′‐sulfonyldiphenol) (PZS). The results showed that CuSn(OH)6@PZS performs most significantly in reducing the total heat release, while the CuSn(OH)6 alone achieves the best smoke suppression effect. The limiting oxygen index (LOI) value of the PVC composites is improved from 29.0% to a maximum of 35.3%. During combustion, the peak heat release rate (PHRR) and total smoke production (TSP) decrease by a maximum of 50.8% and 44.9%, respectively. Significantly, the presence of the PZS coating also improves the interfacial compatibility with PVC. The mechanical properties were significantly improved and the elongation at break improving by 40.9%. [ABSTRACT FROM AUTHOR]

This paper presents the results of tests on elastomer coatings based on polyurea–polyurethane formulation with increased fire parameters. Coatings modified with flame retardants: bis(phenylphosphate) resorcinol (RDP), trischloropropyl phosphate (TCPP), and aluminum hydroxide (ATH) were tested. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA/DTG) were used to investigate the structure and thermal stability. The effectiveness of resorcinol bis(phenylphosphate) (RDP), tris chloropropyl phosphate (TCPP), and aluminum hydroxide (ATH) on heat release rate (HRR), smoke release rate (RSR), and oxygen consumption was evaluated using cone calorimetry. The cone calorimetry results were correlated with the mechanical properties of the coatings. The cone calorimetry analysis showed suitable organophosphorus flame retardant (FR) performance, significantly decreasing HRR and oxygen consumption. Additionally, 15% TCPP caused a reduction of HRR by over 50%, obtaining 211.4 kW/m2 and pHRR by over 55%, reaching 538.3 kW/m2. However, organophosphorus flame retardants caused a significant deterioration of mechanical properties simultaneously. Introducing a mixture of two FRs (RDP/TCPP) resulted in obtaining a coating with improved fire resistance and maintained good mechanical strength. The polyurea–polyurethane coating, modified with a mixture of two RDP/TCPP retardants (10:5), was simulated for the burning of roof systems. The result of the simulation was assessed positively. Thus, finally, it was confirmed that the proposed polyurea–polyurethane coating achieved the assumed flame retardant level. [ABSTRACT FROM AUTHOR]

To develop monoammonium phosphate (MAP) as a novel acid source for durable intumescent fire retardants (IFR), MAP microcapsules (MCMAPs) containing MAP as the internal core and melamine-formaldehyde (MF) as the external shell were prepared by in situ polymerization in this study. The influences of synthesis conditions (including reaction temperature, polymerization time, and reaction pH value) on the properties of obtained MCMAPs (MAP content, yield, morphologies, and thermal properties) were then investigated systematically. The morphologies, chemical structures, and thermal properties were characterized by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetry analyzer (TGA). The results show that MAP was well encapsulated by MF resin. No microcapsules are obtained at <55 °C or with polymerization times <1 h. Optimal preparation conditions of reaction temperature, polymerization time, and reaction pH value are 75 °C, 3 h, and 5.5, respectively. Those results provide process reference and theoretical basis for preparing MCMAPs and could promote the application of MAP microcapsules in wood flame-retardant materials. [ABSTRACT FROM AUTHOR]

The cellulose (Cel)-polyvinyl alcohol (PVA)-sodium alginate (SA) composite aerogels are prepared by adding PVA and SA to the Cel suspension, followed by freeze-drying. The structure and properties of Cel-PVA-SA composite aerogels are determined by FT-IR, scanning electron microscopy, thermogravimetric analysis, limiting oxygen index method and cone calorimetry. The results reveal that sodium alginate is uniformly distributed within the aerogels. The as-synthesized composite aerogels possess excellent compressive resilience properties. In addition, the addition of sodium alginate significantly reduces the flammability of cellulose. Therefore, this study provides a simple method to prepare green flame-retardant Cel-PVA composite aerogels materials, and the aerogels demonstrate excellent potential for application in construction materials. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the effects of talc/intumescent flame retardant additions on thermal, burning, and mechanical characteristics of the rigid polyurethane foams. At this purpose, the talc which mainly includes SiO2, MgO and CaO and an intumescent flame retardant which is composed of ammonium polyphosphate and pentaerythritol was incorporated into the foam at various weight loadings. The cone calorimeter tests, UL94 tests, thermogravimetric analyses and thermal conductivity measurements were done for investigation of the thermal and burning characteristics. In general, additions of the talc and the talc/the intumescent flame retardant enhanced the thermal and the fire resistance of the foams. However, the best fire resistance was achieved with a composition which include 10 wt % the intumescent flame retardant and 5 wt % talc. The addition of this composition resulted in 32% reduction in the total heat release value. [ABSTRACT FROM AUTHOR]

Thermal management systems are critical to the maintenance of lithium-ion battery performance in new energy vehicles. While phase change materials are frequently employed in battery thermal management systems, it's important to address the concerns related to their leakage and flammability, as they can pose hazards to the safety performance of batteries. This paper proposes a novel flame retardant composite phase change material (CPCM) consisting of paraffin, high-density polyethylene, expanded graphite, ammonium polyphosphate, red phosphorus, and zinc oxide. The performance of CPCMs containing different ratios of flame retardants is investigated, and their effects when applied to battery thermal management systems are compared. The results demonstrate that the leakage rate of the flame retardant CPCMs is maintained within 1%, indicating excellent flame retardant performance and thermal management efficiency. The combination of ammonium polyphosphate and red phosphorus in the flame retardant exhibits effective synergistic effects, while zinc oxide may help phosphate compounds create their bridging bonds, which would then make it possible to construct a char layer that would separate heat and oxygen. Under a 2C discharge rate, the maximum temperature of the battery pack remains below 50 °C, and the temperature difference can be controlled within 5 °C. Even under a 3C discharge rate, the maximum temperature and temperature difference are reduced by 30.31% and 29.53%, respectively. [ABSTRACT FROM AUTHOR]

Epoxy resins (EP) have great chemical and physical properties, but their poor flame retardant properties have prevented their widespread use. To improve the flame retardancy properties of EP, an active P/N/Si flame retardant (KDC) containing a double bond was successfully synthesized in this work by using a typical aldehyde amine condensation reaction. This flame retardant not only can form a large molecule flame retardant in situ by double bond reaction and increase the tightness with EP matrix, but also has the advantage of P/N/Si three elements synergistic flame retardant, and at the same time play the flame retardant performance of each element, can achieve excellent flame retardant performance and low smoke and toxicity with low addition amount. Subsequently, the performance of the flame retardants was tested. When 7 wt% of KDC was added, the pHRR and TSR of the EP composites were reduced by 51.7% and 29.8%, respectively. More importantly, the addition of KDC inhibited the release of toxic fuels and smoke from EP, where the TSP values of EP/3‐KDC were 18.14% below those of neat EP and increased the residual amount of charcoal, while the inhibition of CO and CO2 release was particularly pronounced with the presence of KDC. [ABSTRACT FROM AUTHOR]

This study presents the preparation and flammability characteristics of polymeric composites based on the epoxy resin Epidian® 601. The triethylenetetramine (TETA) and commercial curing agents based on polyamines (IDA and PAC) were used as crosslinking compounds. Moreover, two flame retardant compounds were added to this composition, the commercial Fire Retardant (FR) and triphenyl phosphate (TP). The chemical structure of the composites and the course of curing processes were confirmed by the ATR/FT-IR (Attenuated Total Reflection–Fourier Transform Infrared) analysis. The influence of different amounts of FR or TP on the flammability and thermal resistance was discussed in detail. After the flammability test the samples were also studied to assess their thermal destruction. In addition, the composites were subjected to the swelling tests, solvent resistance, and microscopic observations. The DSC curves revealed that all materials were characterized by good thermal properties. All materials were temperature resistant up to 300 °C. Furthermore, the measurements of the hardness of the composite demonstrated that the material EP601 + TETA + 10 %FR is the hardest. The addition of FR and RP influenced the flammability of the composites increasing the thermal resistance. The ageing tests in methanol, acetone, hydrochloric acid, and potassium hydroxide were also carried out. [ABSTRACT FROM AUTHOR]

The effects of a warm-mix agent, PN2217, on the rheological properties and thermal stability of alumina trihydrate/organic montmorillonite (ATH/OMMT) composite flame-retardant asphalt were investigated in this study. Dynamic shear rheological and multiple stress creep recovery tests were performed to investigate the high-temperature rheological properties of ATH/OMMT flame-retardant asphalts with different amounts of PN2217. Thermogravimetry–differential scanning calorimetry was performed to evaluate the thermal stability of the asphalt binders. Kinetic analyses were conducted to investigate the combustion mechanism. Fourier-transform infrared (FTIR) spectroscopy and atomic force microscopy were performed to investigate the reaction mechanism of PN2217 with the ATH/OMMT flame-retardant asphalt. The microstructure of the combustion residue was analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The FTIR spectra revealed no chemical change after the addition of PN2217 to the flame-retardant asphalt. The results indicated that PN2217 adversely affected the elastic response and rutting resistance of the ATH/OMMT asphalt because the intercalated structure formed by the intercalation of the asphalt molecules into OMMT was transformed into a phase-separated structure in the presence of PN2217. Moreover, PN2217 adversely affected the thermal stability of the ATH/OMMT asphalt by reducing the activation energy and preventing the formation of a char layer during combustion. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) is derived from crops, and has a broad application prospect in electronics and electrical, automotive industries due to its biodegradability and good physical and mechanical properties. However, PLA's flammability and serious melt dripping cannot meet the requirements of terminal products, thus limiting its application. Over the past decade, much research on flame retardant PLA has emerged. This paper reviews the development of PLA flame retardants in recent years, focusing on phosphorus‐based, phosphorus–nitrogen‐based, bio‐based, nanoparticles, intumescent flame retardants, and their combinations. Besides that, the efficiency of flame retardant and its loading on the thermal and mechanical properties of PLA is also thoroughly reviewed. Finally, the future development of flame‐retardant PLA is briefly summarized and prospected. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study concentrated on the influence of rice husk biochar on the structural, thermal, flammable, and mechanical properties of recycled high-density polyethylene (HDPE). The percentage of rice husk biochar with recycled HDPE was varied between 10% and 40%, and the optimum percentages were found for the various properties. Mechanical characteristics were evaluated in terms of the tensile, flexural, and impact properties. Similarly, the flame retardancy of the composites was observed by means of horizontal and vertical burning tests (UL-94 tests), limited oxygen index, and cone calorimetry. The thermal properties were characterized using thermogravimetric analysis (TGA). For detailed characterization, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) tests were performed, to elaborate on the variation in properties. The composite with 30% rice husk biochar demonstrated the maximum increase in tensile and flexural strength, i.e., 24% and 19%, respectively, compared to the recycled HDPE, whereas the 40% composite showed a 22.5% decrease in impact strength. Thermogravimetric analysis revealed that the 40% rice husk biochar reinforced composite exhibited the best thermal stability, due to having the highest amount of biochar. In addition, the 40% composite also displayed the lowest burning rate in the horizontal burning test and the lowest V-1 rating in the vertical burning test. The 40% composite material also showed the highest limited oxygen index (LOI), whereas it had the lowest peak heat release rate (PHRR) value (52.40% reduced) and total heat release rate (THR) value (52.88% reduced) for cone calorimetry, when compared with the recycled HDPE. These tests proved that rice husk biochar is a significant additive for enhancing the mechanical, thermal, and fire-retardant properties of recycled HDPE. [ABSTRACT FROM AUTHOR]

Carrageenan fibers crosslinked with trivalent metal ions (Al3+ or Fe3+) were prepared into carrageenan fiber paper (Al/CAP, Fe/CAP) by the Rapid Kothen method, and their flame-retardant mechanism and flame retardancy were studied through LOI, VF, SEM, CONE, and TGA testing. The results showed that Al/CAP exhibited good flame retardancy and thermal stability, and its LOI value reached 52%. Meanwhile, the afterflame time and afterglow time of Al/CAP were 0 and 1 s, respectively, which indicated that it was not ignited and almost had no smoldering phenomenon. The flame-retardant performance of Fe/CAP is inferior to that of Al/CAP, with LOI of 32, but the total smoke emission (TSP) of Fe/CAP is lower in cone calorimetry test. Thus, CAPs (especially Al/CAP) can be widely used in the flame-retardant paper industry, due to their flame retardancy and environmental protection. [ABSTRACT FROM AUTHOR]

In this work, the results of investigations of polyurethane materials were presented. Innovative materials based on polyurethane-polyisocyanurate (PUR/PIR) foam were obtained. Different types of additives (flame retardants, aerogels – additives that decrease thermal conductivity) are used in the composition of PUR/PIR foam. Foams are a type of composite composed of two phases: continuous (polyurethane polymers) and dispersed (composed of gases). All samples have been tested for thermal parameters: thermal conductivity, specific heat, and thermal diffusivity. Then they have been compared with each other and with a reference sample (RS) without additives. Based on the research, it was shown that innovative insulation materials were characterized by thermal conductivity λ in the range of 0.0254–0.0294 W/(m · K). The thermal properties of foams depending on the type and chemical composition of the material. Depending on the used substrates, their molar ratio, type, synthesis conditions, modifying agents and catalysts, a different polyurethane material is obtained. [ABSTRACT FROM AUTHOR]

Lignin can be used as a sustainable alternative to bisphenol A (BPA) to prepared lignin-based epoxy resins. Lignin effects including molecular weight, phenolic content, G/S unit ratio and flexible/rigid linkage ratio on epoxy synthesis and performance were summarized comprehensively. The incorporation of lignin with a higher molecular weight would lead to the higher rigidity of epoxy crosslinking network. Higher contents of ether bonds in lignin would provide higher structural flexibility of lignin incorporated epoxy thermosets. Lignin with higher contents of phenolic hydroxyls was more beneficial for improving the reactivity of its epoxy products after glycidylation. Due to the excellent charring capacity of lignin, higher contents of residue char can be produced at higher additions of lignin at high temperatures, while the loss of crosslinking density caused by the increasing lignin addition (especially for the macromolecular lignin) would deteriorate the thermal stability of their thermosets. Several applications of lignin-based epoxy resins were also mentioned based on their mechanical, thermal and chemical properties, such as coatings (with anticorrosion and UV-blocking), adhesives (with highly crosslinking network, excellent mechanical, and thermal properties) and flame retardants (with high charring capability). [Display omitted] [ABSTRACT FROM AUTHOR]

This study investigated suspending two fire retardants in sugar-cane bagasse plies used for manufacturing natural fibre reinforced composites. Sugar-cane bagasse was alkali treated, blended with either APP (Ammonium Polyphosphate) or ATH (Aluminium Hydroxide), pressed and dried to form plies. Composites were manufactured using a light resin transfer moulding process with epoxy resin. Composites manufactured with fire retardant suspended plies were compared to composites with plies layered with equivalent amounts of fire retardants. The composites were characterised using thermogravimetric analysis (TGA) for thermal stability and char yield, isotropic hot disc method for thermal properties, and cone calorimeter for studying ignition and flammability. Plies suspended with APP had the highest char yield of 58% (in nitrogen), reducing to 26% in the composite form, with degradation driven by the epoxy matrix. The composite layered with ATH had the latest ignition times of 118 s when tested with a radiant heat flux of 35 kW/m2. The composite layered with APP displayed the lowest average heat release rate (179.7k W/m2), peak heat release rate (305.6k W/m2), and total heat released (135.5 MJ/kg). When assessing the fire growth, the composite layered with APP was again favourable. While the layering yielded more favourable results than the suspension of the same retardants, this study showed that a rudimentary process was able to suspend enough retardants to improve the behaviour of the resulting composites in a fire scenario. [ABSTRACT FROM AUTHOR]

Polymeric aluminum organophosphates are a class of nanostructured aluminum-based compounds that can be considered organic and inorganic hybrid materials. Aluminum phosphates have attracted considerable interest due to their ability to enhance composite materials' mechanical characteristics, lightweight, and thermal properties. Extensive studies have shown the potential of aluminum organophosphates as a component in the development of fire-retardant materials. Aluminum–organophosphorus hybrid (APH) materials have been prepared by reacting aluminum oxide hydroxide (boehmite) with alkyl and aryl phosphoric acids and used to prepare composites with epoxy resin. Boehmite is an aluminum oxide hydroxide (γ-AlO(OH)) mineral, a component of the aluminum ore bauxite. In this work, the composites based on epoxy resin Epidian 601 and commercial curing agent IDA were obtained. Pure boehmite and APH hybrids were added as flame retardants. FTIR and TGA analysis showed that obtained APH possesses a hybrid structure, high thermostability, and various morphologies. These new APH were incorporated into epoxy resin. The infrared spectroscopy confirmed the structure of hybrids and composites. Pyrolysis combustion flow calorimetry (PCFC) and cone calorimeter analyses were performed to assess the flame retardant properties of the composites. The results showed that the incorporation of 17 wt% APH allows a reduction of heat release rate but to a limited extent in comparison to pure boehmite, which is due to the different decomposition mechanisms of both boehmite and hybrids. The cone calorimetry test showed that residue contents correspond quite well to the mineral fraction from boehmite only. The hybrid APHs appear no more efficient than pure boehmite because the mineral fraction in APH is reduced while phosphate fraction cannot promote significant charring. [ABSTRACT FROM AUTHOR]

The inflammability of polystyrene (PS) limited its application. In order to improve the flame retardancy of PS, developing reactive-type flame retardants is a promising approach. In this work, a novel N-arylpiperazine phosphoramidate monomer, 2-((phenoxy(4-phenylpiperazin-1-yl)phosphoryl)oxy)ethyl methacrylate (PPPEM), was facilely synthesized and used as a reactive-type flame retardant. The obtained monomer was then copolymerized with styrene through the free radical bulk polymerization. The thermal stability of copolymers was measured by the thermogravimetric analysis. The addition of the PPPEM units increased decomposition temperature of the copolymers, indicating the improvement of the thermal stability. The glass transition temperature of the copolymers remained little changed with varied amount of the PPPEM, implying that the introduction of PPPEM units did not evidently affect the mobility of the PS main chain. The flammability of the copolymers was evaluated by microscale combustion calorimeter (MCC) and limiting oxygen index (LOI). According to the MCC and LOI results, PPPEM unites can contribute to the decrease of the peak heat release rate, the increase of LOI and improvement of the flame retardancy. The novel N-arylpiperazine phosphoramidate monomer show a great potential for application in reactive-type flame retardants. [ABSTRACT FROM AUTHOR]

With the increase in environmental pollution, studies on the use of sustainable resources are increasing day by day. For this purpose, the use of natural fiber-reinforced polymer composites is encouraged in many areas such as automotive, transportation, construction, and home textiles. However, they are flammable and therefore seriously threaten the safety of people and property. Various flame retardant additives have been used to improve the flame retardancy properties of these composites. In this study, silicon dioxide (SD) and zinc borate (ZB) microparticles in different weight percentages (3, 5, 7, and 10%) were reinforced to give flame retardant properties to jute-epoxy composites. In addition, composites containing both SD and ZB microparticles were produced and they were labeled as HB. Then, thermal conductivity, flammability, water absorption, and mechanical properties of these composites were investigated. The burning rate of the composites decreased as the amount of microparticle increased. 5ZB5SD, including %5 SD and %5 SD microparticles, showed 36.60% less burning rate than the neat jute-epoxy composite. 5ZB showed 10.84% higher tensile strength than the neat juteepoxy. The impact strength of the specimens increased with the increase in the filling ratio, and 5ZB5SD showed approximately 2.50 times the impact strength of the jute-epoxy composite. [ABSTRACT FROM AUTHOR]

Graphene fibers non-woven fabrics (GFFs) are a new type of carbon-based fabrics formed by the overlapping and fusion of graphene fibers, which have good structural stability, flexibility and excellent electrical and thermal properties. However, the pure GFFs are usually poor electrocatalytic without fire-retardant properties due to the dense structure of graphene fibers and few functional groups on the graphene sheet. Here we report a N, P co-doped GFFs (N, P-GFFs) prepared by wet-fusing assembly graphene oxide fibers containing hexachlorocyclotriphosphazene (HCTP) and pyrolysis of the mixture. The introduction of N and P atoms increases the active sites of GFFs, which significantly enhances its electrocatalytic activity, and also makes GFFs with high flame-retardant performance. The newly developed multifunctional refractory nonwoven fabrics are promising great potential in real-world applications. [ABSTRACT FROM AUTHOR]

The present study explores the use of a wastage tea extract, as a green flame retardant for application on cotton fabrics. The treated cotton fabric was characterized by limiting oxygen index (LOI), vertical flammability, Fourier transform infra-red spectroscopy (FT-IR) studies and wastage tea extract was characterized by gas chromatography and mass spectroscopy (GC-MS) analysis. Results revealed that the fabric treated with wastage tea extract demonstrated the LOI value of 29 as compared to LOI value of 18 observed for control fabric. Treated fabric also exhibited self-extinguishing behavior with specific char length of 30 mm. GC-MS study of tea extract revealed that it contains various large molecular weight polyphenolic compounds and the presence of tannin containing products, responsible for the fire retardancy action. Mechanism of fire retardancy unveiled the fact that the various nitrogen containing alkaloids, long-chain carbon molecules and polyphenolic compounds deposited on the cotton fiber surface, combinedly assist on the flame retardancy and stable char formation of the underlying cellulosic structure. This study opens up the scope for the application of wastage tea extract on cotton textiles, which is a promising and emerging field in sustainable flame retardancy. [ABSTRACT FROM AUTHOR]

The alloying synergistic flame retardant effect was studied by using polyetherimide (PEI) and aluminum diethylphosphinate (ADP) for polyamide 6 (PA6), which can endow PA6 composites with excellent mechanical properties and flame retardancy simultaneously. On the one hand, because the molecular structures of PEI and PA6 are similar, adding PEI with PA6 can form PEI‐PA6 alloy by the hydrogen bond effect and nice homogeneous phase, which can endow PA6 composites with excellent mechanical properties. On the other hand, the test results of flame retardancy show that 9ADP/10PEI‐PA6 composite can obtain higher LOI value (LOI = 31%), and excellent flame retardant rating (UL94 V‐0) with 9%ADP and 10%PEI. From the results of cone calorimetry test, the pk‐HRR and THR of 9ADP/10PEI‐PA6 are reduced by 24.4% and 24.7%, respectively, compared to PA6, and higher char residue rate was obtained, which shows that ADP combined with PEI‐PA6 alloying exerts an excellent flame retardant synergistic effect. Through the study of flame retardant mechanism found that ADP works together with PEI can effectively increase the quenching effect in the gas phase, promote thermal stability, and delay the decomposition process of PA6 matrix during the combustion process. Meanwhile, it also increases the char yield to exert a synergistic effect in the condensed phase by ADP/PEI‐PA6. The residual char rate reached 36.6%, higher than neat PA6 about 4.6 wt.%. Thus, the alloying flame retardant method using ADP/PEI‐PA6 can endow PA6 with better flame retardancy and more excellent mechanical properties. Importantly, it provides a new direction for developing high‐performance halogen‐free flame retardant materials. [ABSTRACT FROM AUTHOR]

Natural fibers have emerged as a potential alternate to synthetic fibers, because of their excellent performance, biodegradability, renewability and sustainability. This research has focused on investigating the thermal, visco-elastic and fire-retardant properties of different hybrid Cytostachys Renda (CR)/kenaf fiber (K) (50/0; 35/ 15, 25/25, 15/ 35, 0/50)-reinforced MWCNT (multi-walled carbon nanotubes)-modified phenolic composites. The mass% of MWCNT-modified phenolic resin was maintained 50 mass% including 0.5 mass% of MWCNT. In order to achieve homogeneous dispersion ball milling process was employed to incorporate the MWCNT into phenolic resin (powder). Thermal results from thermogravimetric analysis and differential scanning calorimetric analysis revealed that the hybrid composites (35/15; 35 mass% CR and 15 mass% K) showed higher thermal stability among the composite samples. Visco-elastic results revealed that kenaf fiber-based MWCNT-modified composites (0/50; 0 mass% CR and 50 mass% K) exhibited higher storage and loss modulus due to high modulus kenaf fiber. Fire-retardant analysis (UL-94) showed that all the composite samples met H-B self-extinguishing rating and exhibited slow burning rate according to limiting oxygen index (LOI) test. However, (15/35; 15 mass% CR and 35 mass% K) hybrid composites showed the highest time to ignition, highest fire performance index, lowest total heat release rate, average mass loss rate, average fire growth rate index and maximum average rate of heat emission. Moreover, the smoke density of all hybrid composites was found to be less than 200 which meets the federal aviation regulations (FAR) 25.853d standard. Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) was carried out to select an optimal composite sample considering the thermal, visco-elastic and fire-retardant behaviors. Through TOPSIS analysis, the hybrid (15/35; 15 mass% CR and 35 mass% K) composite sample has been selected as an optimal composite which can be used for high-temperature aircraft and automotive applications. [ABSTRACT FROM AUTHOR]

In order to improve the flame‐retardant properties of epoxy resin (EP) without sacrificing the mechanical properties, a high‐efficient P/N/S‐containing reactive flame retardant (VTZD) was synthesized by a facile one‐pot method from vanillin, 2‐aminobenzothiazole and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO), and used in epoxy‐amine thermosets. When 5 wt% of VTZD was added with merely 0.31 wt% of phosphorus, the LOI value of cured resins increased to 32.7%, and the thermosets achieved a UL‐94 V‐0 rating. Furthermore, the peak heat release rate and the total heat release of the VTZD‐modified EP decreased by up to 34.66% and 32.49%, respectively, in comparison to those of the original EP. Subsequently, the residual char morphology and structure of epoxy thermosets were investigated, as well as the pyrolysis behavior of VTZD. The flame‐retardant mechanism was discussed in detail, and it confirmed that VTZD exhibited a bi‐phase flame retardant effect. In addition, the mechanical properties of the cured products were well maintained and even improved. All the results demonstrated that the VTZD was a bio‐based high‐efficiency flame retardant for EP with a broad prospect in practical applications. [ABSTRACT FROM AUTHOR]

The mountmorinollite (MMT) nano clay, microcrystalline cellulose (MCC), and poly(Lactic acid) (PLA (MMT/MCC/PLA) composites with reinforced strength and toughness were prepared. This study aimed to develop MMT/MCC/PLA composite with improved thermal stability and flame rating based on reinforced strength and toughness. A simple and efficient method to hydrophobize MCC and intercalate the interlayer of MMT by mobilising cerium oxide nanoparticles (CeO2 NP) bearing long-chain saturated fatty acid (Myristic acid; MA) to enhance compatibility with the PLA was adopted. The modified MCC (mMCC) and MMT (mMMT) were incorporated into PLA at different wt%. The flaming rating was studied by adding fire retardant (FR) into the composite. The mMCC, mMMT and their composites were characterised by Fourier Transformed Infrared spectroscopy(FTIR), Scanning Electron Microscopy(SEM), X-ray diffraction, Thermogravimetric analysis(TGA), UL-94 test, Limiting Oxygen Index(LOI), and mechanical analysis. FTIR and XRD confirmed the intercalation of MMT with the CeO2-MA and the mobilisation of CeO2-MA onto the surface of mMCC. SEM study showed the homogenous distribution of mMCC in the PLA matrix and revealed the layered clay structure with the deposition of nanoparticles into the clay interlayer space. The compatibility effect of the MA significantly improved the strength and toughness with more than 100% improvement in tensile strength of mMCC/PLA compared to neat PLA. The flame rating resulted in a 58.8% improvement in the LOI with the addition of the FR. The thermal stability was enhanced by the mMMT and mobility of CeO2 NP into the interlayer space of the clay. The composite of mMCC/PLA, mMMT/PLA, and mMCC/mMMT/FR/PLA attained a V2, V1 and V0 rating in the UL-94 at a low FR addition. The improvement in fire retardancy did not significantly compromise the mechanical properties. The high mechanical performance of the mMCC/PLA presented MA as a potential fiber-matrix compatibiliser. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To seek an effective strategy for improving the compatibility of carboxyl methyl cellulose (CMC) with silica fume‐based geopolymer composite flame‐retarding coatings, a novel silica aerogel (SA) doped inorganic siliceous hybrid coating is fabricated by sol–gel. Results show that an appropriate dosage (0.5 wt%) of SA ameliorates their compatibility thus imparting an enhanced flame resistance, evidenced by the lowest value of fire growth index (0.22 kW·m−2·s−1) decreased by 55% and the average effective heat of combustion (4.16 kW·kg−1) decreased by 31%, the raised flame retardancy index of 5.54 from 1 compared with the control. Because the SA improves the compatibility between the CMC and siliceous colloidal sol, due to its high reactivity, electrostatic repulsion involved in SiO(OH)3−, and high porosity, leading to an enhanced crosslinking during film‐forming of the hybrid coatings. Meanwhile, the reduction between CMC and silica occurs with a swelling fire shield, evidenced by the generated silicon involved in the as‐formed amorphous siliceous residues. Therefore, it proposed a new strategy for optimizing the compatibility of organic–inorganic hybrid fireproof coatings, revealing an efficient design of CMC/inorganic siliceous flame retardants, high‐value recycling technology of solid waste, low‐carbon, and sustainable materials. [ABSTRACT FROM AUTHOR]

Composite industry is constantly seeking multifunctional, high performance and environmentally friendly materials. Herein reported is a novel bio‐based, flame retardant and latent epoxy curing agent synthesized from wood vanillin, phosphate ester and imidazole. Experiment data from combustion test demonstrated that the cured epoxy resin with this new curing agent, designated as VAIP, rendered effective flame retardant property with limit of oxygen of 38.4%, UL‐94 V‐0 rating, total heat release of 48 MJm−2 and peak heat release rate of 435 KWm−2. Thermal mechanical tests showed its significantly higher char yield of 35% at 800°C and thermal stability with the temperature of initial weight loss rate of above 350°C, compared to reference epoxy resins cured by conventional cyano‐imidazole (CEMI). This new phosphorus containing imidazole curing agent also demonstrated potential application in fiber‐reinforced composite by rendering comparable Tg, for both dry and hot‐wet conditions, as well as higher interlaminar and shear strengths, when compared with the reference composite. Dynamic rheological isothermal measurement of the epoxy resin viscosity further concluded that VAIP had significantly better latency of 580 min at 60°C and 14 days at room temperature, resulting in much longer pot life or shelf life for the formulated resins and their prepreg. [ABSTRACT FROM AUTHOR]

Copolymerization of methyl methacrylate (MMA) with flame retardant monomer is considered to be the most promising method for the preparation of transparent flame retardant poly (methyl methacrylate) (PMMA). However, the mechanical strength and heat resistance of the obtained flame retardant copolymers aren't satisfactory. In this work, the organic–inorganic hybrid PMMA copolymer is designed and synthesized by the ternary copolymerization of MMA, octavinyl silsesquioxane (V‐POSS) and phosphorus‐containing flame retardant monomer (DEP). V‐POSS hardly affects the transparency and flame retardancy of the copolymer, but can significantly improve the thermal stability and mechanical properties. When 0.4 mol% V‐POSS is copolymerized, the hybrid copolymer shows limiting oxygen index, heat release rate and visible light transmittance equivalent to the copolymer containing only DEP unit, and the initial decomposition temperature, storage modulus, flexural strength and impact strength are increased by 13°C, 21%, 11% and 23% respectively because of the cross‐linking structure and the enhancement of inorganic nanoparticles. This study illustrates the reinforcing and flame retardant effects of hybrid copolymers, and provides a novel strategy for the preparation of high‐performance flame retardant plexiglass. [ABSTRACT FROM AUTHOR]

In this study, a nanofiller (M‐DOPO‐BN) was synthesized by surface modification of hexagonal boron nitride with vinyltrimethoxysilane (KH‐171) and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO), and compounded with aluminum diethyl phosphinate (ADP) to study their effects on flame retardant, smoke suppression and thermal conductivity properties of styrene‐butadiene rubber (SBR). The results showed that the composites with an ADP content of 20 parts per hundred of rubber (phr) have good flame retardant properties, but the total smoke production increased significantly. The flame retardant properties of SBR composites compounded with 3 phr M‐DOPO‐BN and 17 phr ADP were not only further improved, but also the peak carbon monoxide production rate (pCOP) and peak carbon dioxide production rate (pCO2P) were reduced by 37.0% and 67.5%, respectively, compared with pure samples, showing a good smoke inhibition effect. In addition, the thermal conductivity of the composites have also been improved to a certain extent. The variable temperature infrared and residual char analysis of SBR composites showed that the reasons for its flame retardancy and smoke suppression are that M‐DOPO‐BN can catalyze the formation of carbon, and the silica and boron nitride generated by decomposition during combustion can improve the density of residual char. [ABSTRACT FROM AUTHOR]