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• Tannic acid is neither a good flame retardant nor a highly swelling material. • TA combined with CLS reduces flammability of biocomposite by 30 % compared to PLA. • Mixing of TA with CLS in melt doesn't allow for PHRR reduction of more than 20 %. The purpose of this study was to determine the quantitative and qualitative effects of the form of natural phenolic compounds (NPCs) on the decomposition of polylactide (PLA) under different measurement conditions. For this purpose, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), and pyrolysis-combustion flow calorimetry (PCFC) analyses were carried out not only on individual raw materials like calcium lignosulfonate (BX), tannic acid (TA), BX chemically modified with TA (BMT), but also on PLA/BX, PLA/TA, and PLA/BMT composites with 3, 6, and 9 wt.% of filler. Moreover, the work checked whether to obtain satisfactory results it is necessary to carry out chemical modification lasting many hours, or whether simple physical mixing of ingredients (TABX) is enough, e.g. in proportions 1:2, 2:4, 3:6. The results of these analyses showed that TA is neither a good flame retardant nor a highly swelling material, but when combined with BX physically or chemically, it can produce an interesting synergistic effect. This work proves that chemically obtained BMT hybrid material allows to reduce flammability by 30 % compared to PLA which cannot be achieved by physically mixing these components in a polymer melt. On the other hand, the addition of TABX is sufficient to achieve a good thermal stabilization effect under processing conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper presents research findings on the influence of alkaline deacetylation on the thermal stability and fire reaction properties of non-pathogenic Basidiomycota fungi (mycelium) grown in molasses. The relationship between deacetylation conditions, such as incubation time and NaOH concentration, and the thermal and fire reaction properties of mycelium was investigated. The degree of deacetylation was also examined for its influence on the high-temperature thermal stability of mycelium, such as char formation. The findings indicated that the high-temperature thermal stability increased as the degree of deacetylation increased due to the conversion of chitin into chitosan as well as the presence of char-promoting hydroxyl‑terminated polysaccharide moieties. The study further investigated the influence of hollow glass microspheres on the thermal properties and microscale combustion behaviour of unmodified and deacetylated mycelium. This study provides an in-depth analysis of the thermal degradation mechanisms that govern the thermal stability and char-forming ability of unmodified and deacetylated mycelium. Additionally, the link between the thermal stability and fire reaction properties of mycelium and its deacetylated derivatives was established. Finally, the effectiveness of unmodified and deacetylated mycelium mats for fireproofing flammable glass fibre-reinforced epoxy laminates exposed to a simulated moderate-intensity fire was evaluated. [Display omitted] [ABSTRACT FROM AUTHOR]

A flame retardation property of polymer composites is being considered important to minimize the amount of heat release and the smoke production during the combustion. Therefore, this work aims to improve the flame retardation property of epoxy composites using ammonium polyphosphate (APP), one of the intumescent flame retardants (IFRs). However, APP could be migrated to the surface of composite due to the weak compatibility with epoxy resin. To prevent the migration, the surface modification method has taken place using various amines, acting as charring agent. In this study, we select the 4,4′-diaminodiphenylmethane (DDM) as both curing agent and charring agent for the surface modification on the APP, and their epoxy composites were prepared. Interestingly, we observe both the fast curing effect by analyzing the curing behavior of epoxy composite by Friedman method, and significant improvements of the thermal degradation, and flame retardancy of epoxy with adding the amine-modified APP (mAPP). Moreover, the epoxy/mAPP composites showed higher flame retardation properties and formed the compact char structures due to the attached DDM, which acted as an efficient charring agent to promote to form the carbonaceous char structures. Finally, we also found the correlation between the improvements of flame retardation properties, and char structures of epoxy composites by calculating the crosslink density (M c) using the theory of rubber elasticity. • Amine-modified ammonium polyphosphate was prepared via cationic ion exchange reaction with 4,4′-diaminodiphenylmethane. • The attached DDM can contribute to accelerate the curing and improve the flame retardation properties of epoxy composites.. • The relationship of flame retardation properties and char structure was found using theory of rubber elasticity. [ABSTRACT FROM AUTHOR]

Improving the efficiency of traditional flame retardant additives is a challenging task in the field of wood polymer composites (WPCs). In this work, novel flame retardant system for WPCs was developed based on the combination of ammonium polyphosphate (APP) with phytic acid modified layered double hydroxide (Ph-LDH). Thermogravimetric analysis illustrated that the incorporation of Ph-LDH resulted in earlier thermal degradation of the WPCs with more thermally stable products during degradation, giving improved char formation. Limiting oxygen index (LOI), vertical burning (UL-94) and cone calorimetry tests were used to study the flammability of WPCs and the results showed that the addition of Ph-LDH had a synergistic effect on their fire performance. The char residues of the WPCs after the cone calorimetry tests were characterised by scanning electron microscopy (SEM). Mechanical properties of the flame retardant WPCs were analysed using impact and tensile tests. Partial substitution of APP with polypropylene (PP) resulted in a deterioration in the tensile and impact properties, while co-incorporation of nano-fillers led to an enhancement of the mechanical performances of the flame retardant WPCs. This WPC with good flame retardant and mechanical properties could potentially be used in the fields of building or furniture which require high flame retardancy. Image 1 • Phytic acid (Ph) based modified LDH was successfully used to prepare wood polymer composites (WPCs). • Combination of Ph-LDH and APP showed improved fire performance to WPCs. • New WPCs showed enhanced fire performance and good mechanical properties. [ABSTRACT FROM AUTHOR]

Abstract In order to improve the flame retardancy of PA66, bis- N -benzoguanamine-phenylphos-phamide (MCPO) was grafted to PA66 main chains by end-pieces capping technology. The thermal properties and heat release effect of flame retardant PA66 (FR PA66) composites were investigated by thermogravimetry, differential scanning calorimetry, and cone calorimetry test analyses. In the presence of 8 wt% MCPO in PA66 composites, the initial decomposition temperature (T 5) and peak decomposition temperature (T max) of PA66 composites were 47 °C and 34 °C higher than that of pristine PA66, respectively. Compared to the traditional flame retardant PA66 composites, the heat release rate, total heat release, total smoke production, and CO release rate significantly reduced by 31.3%, 36.3%, 16.9%, and 14.7% by introducing P containing benzoguanamine derivative, respectively. Moreover, the vertical flame spread test illustrated that the melt dripping of PA66 stopped for higher precursor concentrations in the composites carbonized char, and the limiting oxygen index (LOI) value of PA66 composites reached 29% as evidenced by the LOI test. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

The recycled polymeric constituents have a huge potential to be reformed into new products. However, due to the lower toughness of the recycled plastic blends limits it from the further industrial applications. Therefore, current work analyses the potential of nitrile rubber (NBR) on property enhancement of recycled blend, prepared from poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA). The effect of NBR on the mechanical properties of the recycled blend especially toughness, flexural strength and surface hardness were studied in detail. 9 wt% of NBR in the recycled blend has shown a higher toughness value as compared to other systems. Similarly, flammability analysis results reveals that NBR can potentially enhances the flame retardancy of the recycled blend. In addition, NBR effectively changes the rheological properties such as storage modulus, loss modulus and complex viscosity of the recycled blend system. Scanning electron microscope (SEM) and transition electron microscopy (TEM) analysis suggests the possible toughening mechanism present in the recycled blend. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel phosphorus-containing tertiary amine hardener (DCM) is synthesized. • DCM endows epoxy resin with desired heat resistance and char-forming capacity. • DCM improves the mechanical stiffness, robustness and toughness of epoxy resin. • DCM imparts superior flame retardancy and smoke suppression to epoxy resin. Although current phosphorus (P)-based hardeners endowed epoxy resins (EPs) with intrinsic flame retardancy, their addition usually reduced thermal and mechanical properties. In this work, a novel phosphorus-containing tertiary amine hardener (DCM) was synthesized using diphenylphosphinic chloride and 2,4,6-tris(dimethylaminomethyl)phenol (DMP-30), and applied to fabricate high-performance EP/DCM. Introducing P-containing group reduced the reactivity of tertiary amine of DCM, but EP/DCM gelled at 100 °C within 11.3 min, showing modest-temperature curing character. EP/DCM exhibited higher glass-transition temperature (T g) and char yield than virgin EP/DMP-30. Moreover, EP/DCM featured superior mechanical properties, of which the tensile strength, elongation at break and impact strength increased by 61.2%, 72.0% and 198.5%, respectively, relative to those of EP/DMP-30. DCM endowed EP thermosets with remarkable flame retardancy and smoke suppression. The limiting oxygen index (LOI) and UL-94 rating of EP/DCM reached 35.7% and V-0, respectively, with 36.2% and 22.6% reductions in peak heat release rate (PHRR) and peak smoke production rate (PSPR) compared with those of EP/DMP-30. This work pioneers an innovative strategy for creating high-performance EPs with satisfactory heat resistance, fire safety, and mechanical properties by curing with P-containing tertiary amine hardeners. [ABSTRACT FROM AUTHOR]

This study investigated the effects of ammonium polyphosphate (APP) content on the mechanical, thermal and flammability properties of kenaf/polypropylene (KF/PP) and rice husk/polypropylene (RH/PP) composites prepared by melt mixing technique. Polyethyleneoctene grafted maleic anhydride (POE-g-MAH) has been used as compatibilizer. The PP/KF/APP and PP/RH/APP composites were investigated using flexural and impact tests, scanning electron microscope, thermogravimetric analysis (TGA), differential scanning calorimeter and limiting oxygen index (LOI) test. Flexural modulus of PP/KF/APP and PP/RH/APP composites significantly improved from approximately 1.1–2.5 and 0.9–2.1 GPa, respectively, by the addition of 10 phr APP. The flexural strength of the composites also increased by the incorporation of 10 phr APP. In addition, the impact strength of the PP/RH/APP composites increased above 10 phr APP content. From the TGA results, incorporation of APP into PP/RH and PP/KF composites increased the char residue and thermal stability of the composites. Furthermore, the addition of APP increased the flame retardancy of the PP/KF/APP and PP/RH/APP composites with a significant increase of LOI at 10 phr. [ABSTRACT FROM AUTHOR]

Porous polyurethane-polyisocyanurate (PUR-PIR) composites have been synthesized using two types of rapeseed oil-based bio-polyols. The bio-polyols from rapeseed oil were synthesized using two methods: (i) transesterification and (ii) epoxidation followed by oxirane ring opening. The PUR-PIR porous materials were prepared with two isocyanate indices, 150 and 250, and were modified with carbon fibres (CF) in an amount of 3 and 6 wt% of the total foam mass. The structure of the composites was examined using scanning electron microscopy. Thermal and mechanical properties of the composites were determined through a thermogravimetric analysis and measurements of the thermal conductivity, compressive strength, and Young modulus. The influence of CF on the composite flammability was analyzed using oxygen index and cone calorimeter tests. The investigations of the mechanical properties have shown that the compressive strength is the most beneficial in the case of the PUR-PIR foams modified with 6 wt % of CF. The studies have shown that the oxygen index of the composites increases with an increasing CF content and isocyanate index. An addition of CF reduces the heat rate release, especially for the materials with an isocyanate index of 250. An introduction of CF into the PUR-PIR foam structure is a way to improve the thermal stability and to decrease the flammability of final porous composites. [ABSTRACT FROM AUTHOR]

Ceramic-polymer composites with an interpenetrating network structure have a lot of advantages, which can be achieved by connecting two quite different phases. Infiltration of liquid epoxy resin into the cellular alumina matrix is the most suitable way of producing this type of materials and offers an opportunity for a precise and simple fabrication method of ceramic-based interpenetrating composites. Alumina foams manufactured by “gel-casting” method were infiltrated by new tri-functional epoxy resin (triglycidylized para-aminophenol) designed for special aircraft applications. Combination of this new epoxy resin with high-porous alumina foams causes higher compressive strength and better flammability of ceramic/polymer composite than either individual component. Additionally, alumina/epoxy composites with partial pores filling ratio showed satisfactory acoustic absorption characteristics. Development of this type of composites is a result of need to research new, lightweight materials with increased mechanical strength, non-inflammable and another functional features, e.g. noise reduction ability, design for the aerospace industry. Therefore, presented paper investigates flammability, acoustic absorption and mechanical properties of resulted composites. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO 2 ) has versatile applications in a variety of areas. It also shows ability to improve the flame retardancy of flexible poly(vinyl chloride) (fPVC) composite and substitute the conventional toxic flame retardant-antimony trioxide (Sb 2 O 3 ). However, low flame retardant efficiency and ruined thermal stability of the PVC composite in presence of SnO 2 remain to be the most prominent challenges. To address these issues, in this study, hematite (α-Fe 2 O 3 ) zero-dimensional nanoparticles elaborately encapsulated SnO 2 one-dimensional nanorod assemblies and such nanocasting facilitated the formation of hierarchical porosity in favor of high specific surface area and pore volume. The hierarchically nanoporous hybrid was synthesized via a facile and fast bottom-up method in a large scale and all-sided characterization was conducted on the investigation of its structure and fPVC compositions. The extra benefits imparted by α-Fe 2 O 3 in the hybrid improved the flame retardancy of fPVC composite strikingly with reduced amount of harmful HCl gas and suppressed smoke production, without deterioration of thermal stability and mechanical property, showing much better performance than those of Sb 2 O 3 -based fPVC composite. It indicated that this new eco-friendly nanohybrid had a great potential to totally replace antimonial additive. It is expected to pave the pathway about the construction of neoteric porous hybrid nanostructures and open a new avenue to develop high performance nanocomposites. [ABSTRACT FROM AUTHOR]

Dodecyl sulphate (DDS) intercalated magnesium aluminium layered double hydroxide (MgAl DS LDH) and the melamine salt of pentaerythritol diphosphate (MPP) were synthesized and used as additives for the preparation of epoxy nanocomposites. The properties of the additives and their epoxy polymer nanocomposites were characterised by X-ray diffractometer (XRD), FTIR, 1 H NMR, 13 C NMR, 31 P NMR, SEM, TEM, TGA, Limited Oxygen Index (LOI) and Underwriters Laboratories-94 Test (UL-94). The MgAl DS LDH additions to the MPP in the epoxy resin protect the polymer from thermal oxidation, which was shown by a stable enhancement of the thermal and flammable properties of the nanocomposites. Due to the presence of MgAl DS LDH, the epoxy nanocomposites developed a rigid and dense upper layer, with stable charring, which prevented the escape of the decomposed flammable volatiles and protected the lower layer of the nanocomposites from further decomposition. This char was characterized by FTIR. MgAl DS LDH shows a synergistic effect in the thermal and flammable properties of an epoxy nanocomposite, in the presence of MPP. [ABSTRACT FROM AUTHOR]

• A bio-based, phosphorus-phosphorus, hyperbranched oligomer (DIT) was synthesized. • DIT enabled EP to achieve durable fire safety. • DIT significantly improved mechanical robustness and toughness of EP. • DIT well maintained high transparency and thermal resistance of EP. The manufacture of transparent, durable fire-safe, strong yet tough epoxy resins (EPs) remains a great challenge. Herein, a novel hyperbranched, P-P synergetic, bio-based flame retardant (DIT) was synthesized, which was composed by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), bio-derived itaconic anhydride (ITA) and trihydroxymethylphosphine oxide (THPO) moieties. Adding 2 wt% DIT enabled the EP/2DIT sample to achieve a UL-94 V-0 rating and a limiting oxygen index (LOI) of 36.6%. The peak heat release rate and total smoke production of EP/4DIT sample with 4 wt% DIT were 23.8% and 19.9% lower than those of virgin EP sample. Notably, the EP/DIT sample featured durable flame retardancy because of the oligomeric structure of DIT. The high flame-retardant efficiency of DIT was mainly due to the synergism between DOPO and THPO. DIT simultaneously strengthened and toughened EP thermoset at a low addition (≤2 wt%), and 2 wt% of DIT increased the elongation at break, tensile strength, flexural strength and impact strength of EP/2DIT sample by 35.8%, 40.5%, 24.2% and 21.2%. Moreover, the glass transition temperature (T g) of EP/2DIT sample was equal to that of EP sample, and the high transparent was maintained. Hence, this work offers an all-rounded design for the creation of durable flame-retardant EPs with superior mechanical properties, thermal resistance and transparency by introducing hyperbranched, P-P, bio-based flame retardants, which shows huge potential and broad prospect. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, the graphite oxide was prepared by modified Hummers method, and 9,10-dihydro-9-oxa -phosphaphenanthrene-10-oxide (DOPO) was grafting on the graphene by acylating chlorination method to prevent aggregate and gain synergistic flame retardancy. Graphene–DOPO was characterized by fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). Carbon fiber/epoxy resin (CF/ER) composites containing graphene-DOPO were prepared by hot pressing method. And the flammability properties of the composites were investigated. Composites with 3 wt% graphene-DOPO increased the LOI value from 18.5% to 28%and can reach UL-94 V-1rating during the vertical flame tests. Moreover composites with 3 wt% graphene-DOPO reduced the total heat release (THR) from 16.1 to 12 kJ/g. The same tendency was acquired from the peak heat release rate (PHRR) showing positive effect of graphene-DOPO in improving the flame retardancy of CF/ER composites. TGA results demonstrated that the char residues of composites increased with the addition of graphene–DOPO. [ABSTRACT FROM AUTHOR]

In this study, bamboo polymer composite (BPC) was prepared by blending of high-density polyethylene (HDPE) with boric acid - borax (Ba-Bx) pre-treated bamboo fibers as reinforcement material and by using maleic anhydride grafted polyethylene as coupling agent. BPCs were incorporated with conventional flame retardants (FRs) additives such as ammonium polyphosphate (APP) along with nano particles such as silicon dioxide (nano-SiO 2) and flame performance was investigated using cone calorimeter and limiting oxygen index analysis (LOI). The thermal behaviour of BPC was investigated under nitrogen atmosphere using thermogravimetric analyser (TGA). The maximum improvement in flammability was achieved with flame additive i.e., Ba-Bx 5%/APP15%. LOI value was found to be highest at Ba-Bx 5%/APP 13%/nano-SiO 2 2%. Mechanical properties of BPCs were analysed using flexural and tensile tests. While the flame and thermal properties of BPCs was improved significantly, the strength properties were marginally reduced due to application of FR additives. In general, APP as synergist with Ba-Bx improved thermal stability and flammability of BPCs. The effects of boron compounds (BCs) utilization as synergists with ammonium polyphosphate (APP) on the mechanical and fire retardant (FR) properties of wood polymer composites (WPCs) manufactured from wood flour, HDPE, MAPE is known through work by Kurt et al. (2012). BCs acts as synergist with APP, however, reduced mechanical properties of WPCs is an imminent result in this combination. Studies in the past have reported on reduced strength properties of wood or lignocellulosic biomass due to BCs treatment (Nagieb et al., 2011; Toker et al., 2009 etc). Further, additives with nano-scale, such as nanoclay, carbon nanotube, and nano-SiO2 are incorporated to polyethylene, polypropylene, and acrylic polymer for improving the tensile and flexural properties of the composites. Thermal stability, hardness, flame retardancy, and water resistance capacity were also found to enhance with addition of nano SiO 2. Pan et al. (2014) have investigated the synergistic effects of the combination of APP and nano-SiO2 on the flame retardant properties of WPCs, and APP/nano-SiO2 has significant improvement on heat release rate, total heat release, time to ignition, mass loss rate, and limited oxygen index. The most efficiency was appeared in APP 8%/nano-SiO2 6%. There is little or no information on synergistic effects of the combination of BCs, APP and nano-SiO2 on the flame retardancy, strength, thermal and recyclability properties of WPC. [ABSTRACT FROM AUTHOR]

The structure, flame speed and stability of freely propagating combustion waves in rich hydrogen–air mixtures is investigated numerically using models with detailed and reduced two-step kinetic mechanisms. The critical conditions for the onset of diffusive-thermal pulsating instabilities are found in the equivalence ratio vs pressure parameter plane in each case. The oscillating solutions emerging as a result of these instabilities are investigated. It is demonstrated that the models with reduced kinetics are able to qualitatively (models with constant density) and quantitatively (models with variable density) predict the flame characteristics and stability as compared to the models with detailed reaction mechanism. [ABSTRACT FROM AUTHOR]

The objective of this research was to investigate the effect of non-durable flame retardant (NDFR) coating of samples of polyester fabric untreated and treated with UV/Ozone for different periods. For this purpose, these samples were tested by Fourier transform infrared (FTIR) spectroscopy, thermal analysis tests as thermo-gravimetric analysis (TGA) and differential scanning calorimeter (DSC). The ignition test was applied using limiting oxygen index (LOI), flame chamber (UL/94). Results indicated that both AZ2 (dried at room temperature) and AZ8–12 (dried at 80 °C for 30 min after coating with non-durable fire retardant (NDFR) coating) polyester samples have significantly decreased the rate of burning and increased the limiting oxygen index. [ABSTRACT FROM AUTHOR]

To study the influence of fuel temperature on performances of biodiesel engine, combustion and emission performances of biodiesel engine at different fuel temperatures are tested and studied. It is found with the increase of fuel temperature, combustion pressure and instantaneous heat release rate curves leave far away from the top dead center and at high loads the combustion delays obviously; peak combustion pressure and peak instantaneous heat release rate decrease and at high loads the reduction increases; the backward combustion increases; at 1500 r/min, compared with 25 °C, NO X emissions of biodiesel at 40 °C and 55 °C averagely decrease by 7.6% and 9.1%, but smoke emissions averagely increase by 29.1% and 54.1%. Results indicate that fuel temperature has important influence on performances of biodiesel and it can be selected as a basic parameter to control the combustion and emission of biodiesel. [ABSTRACT FROM AUTHOR]

This paper investigates the reinforcement of rigid polyurethane foams with carbon nanotubes or graphite in order to improve their mechanical and thermal properties as well as fire resistance. A small addition of carbon nanotubes (up to 0.05 wt.%) improves the mechanical strength by about 20%, which was attributed to the strengthening effect of nanotubes and the change in the foam structure, i.e. the smaller size of pores and their narrower distribution. For higher nanotube content, the pore size does not change but the overall porosity significantly increases which results in a decrease in the mechanical strength. The thermal stability of nanocomposite foams and their flammability increase as a result of the formation of a carbon layer forming at the polymer surface. The addition of graphite greatly improves the fire resistance of polyurethanes foams but significantly deteriorates the bending strength due to the poor adhesion to the polyurethane matrix. [ABSTRACT FROM AUTHOR]

Novel and facile method was developed for the synthesis of graphene based flame retardant for acrylonitrile-butadiene-styrene. Graphene has been exfoliated by using ultrasonication in maleate diphosphate as dispersant. The exfoliation media produced high quality less defected graphene layers. The graphene wrapped with maleate diphosphate was decorated with TiO 2 nanoparticles with an average size of 21 nm. Polymer composites of acrylonitrile-butadiene-styrene with maleate diphosphate, graphene wrapped with maleate diphosphate and decorated ones have been synthesized with solvent blending method. The flammability properties of the polymer nanocomposites were significantly reduced. The peak heat release rate (PHRR) and total heat release (THR) of the polymer nanocomposites contains nanoparticles decorated graphene achieved 49% reduction. Also, average mass loss rate was reduced by 50% and emission of carbon dioxide was suppressed by 37%. The rate of burning of nanocomposites was found to be 12 mm/min compared to virgin polymer of 42.5 mm/min achieved 71% reduction. The effect of combining graphene and the materials was investigated. The graphene wrapped with maleate diphosphate and maleate diphosphates itself were characterized using FTIR spectroscopy. The different polymer nanocomposite materials were characterized using thermal gravimetric analysis, UL94 flame chamber and cone calorimeter. The exfoliation of graphene was elucidated by Raman spectroscopy and XRD and the dispersion of graphene sheets in maleate diphosphate and their decorated composites with nanoparticle were characterized using transmission electron microscopy. [ABSTRACT FROM AUTHOR]

A series of polycarbonate (PC)/acrylonitrile butadiene styrene (ABS) (70/30 wt.%) nanocomposites with varying concentrations (0–5 wt.%) of multilayer graphene particles (GNP) were fabricated using melt extrusion process. The flammability, thermal, mechanical and morphological properties of the nanocomposites was investigated. Cone calorimeter analysis, limiting oxygen index (LOI) and UL94 flame rating tests revealed that addition of GNP to PC/ABS significantly improved the flame retardancy of PC/ABS/GNP nanocomposites. As much as 30.4% reduction in peak heat release rate was observed for the 3 wt.% GNP loading. The maximum LOI value of 26% was observed for the nanocomposites with 3wt.% GNP content. UL-94 V-2 rating and less dripping was observed for the nanocomposites compared with the pure PC/ABS sample. TGA analysis showed that incorporation of GNP enhanced the thermal stability and char yield of the nanocomposites. Scanning electron microscopy revealed the GNP nanoplatelets were unidirectionally aligned in the PC/ABS parallel to the surface of the nanocomposites. [ABSTRACT FROM AUTHOR]

The flammability, thermal and mechanical properties on cotton fabric were improved by being finished with the composite containing montmorillonite. To this aim, polymer dimethyl diallyl ammonium chloride-allyl glycidyl ether (P DMDAAC-AGE ) was prepared and its structure characterized by Fourier transform infrared (FT-IR) and Nuclear magnetic resonance ( 1 H NMR). The quaternary ammonium salt copolymer/montmorillonite composite (P DMDAAC-AGE /MMT) was obtained by polymer intercalation method. The X-ray diffraction (XRD) indicated that the MMT interlayer spacing increased after the polymer intercalation. Composite materials were loaded onto the cotton fabrics by a dip-pad-dry method. The thermo gravimetric analysis (TGA), vertical flame test and limiting oxygen index (LOI) results showed that the thermal and flammability properties of the cotton fabric were improved after it was finished with the composite. Tensile testing revealed an increase on mechanical properties of the finished fabric, but the physical properties hardly changed from the bending length and whiteness results. Scanning electron microscope (SEM) and energy disperse X-ray spectroscope (EDX) results verified the improvement of those properties due to the presence of montmorillonite in the composite. [ABSTRACT FROM AUTHOR]

Ethylene-vinyl acetate (EVA)/sepiolite nanocomposites were prepared by melt blending in a twin screw extruder. The structural, morphological, thermal, flammability and mechanical properties of the EVA/sepiolite nanocomposites were investigated using X-ray diffraction (XRD), Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), thermal analysis, tensile properties and limiting oxygen index (LOI) measurements. X-ray diffraction analysis and FESEM revealed good dispersion of sepiolite in EVA matrix. The tensile strength of EVA/sepiolite increased by 21% and Young's modulus increased by 47% at 5 wt% and 7 wt% sepiolite content, respectively. The thermal stability and fire retardancy of the nanocomposites improved with sepiolite incorporation. [ABSTRACT FROM AUTHOR]

• Novel Mg-Y-Gd-Ca alloy with different element content prepared by casting. • The amount of alloying elements in solid solution increases with higher content. • Superior ignition temperature of 1095 °C is achieved by Mg-2Y-2Gd-1Ca alloy. • Oxide layer containing Y 2 O 3 CaO and Gd 2 O 3 suppressed the burning of the samples. The ban by the Federal Aviation Administration (FAA) of application of magnesium in aircraft cabins was lifted under the condition that the used materials have to fulfill the requirements for the ignition tests. This work proposes the novel Mg-2Y-2Gd-1Ca alloy with a small amount of Y, Gd and Ca as main alloying elements. Superior ignition temperature of 1100 °C was determined for this alloy. Analysis of the oxide layers revealed the presence of Y 2 O 3 , CaO, Gd 2 O 3 , and MgO in oxide layers which were observed to significantly suppress ignition compared to the pure Mg. [ABSTRACT FROM AUTHOR]

This work reports our recent effort on the preparation of α-Phenyl-N-(2-propyl-2-hydroxymethyl-1, 3-dihydroxy)-imine-Nickel (Ⅱ) (Ni-MOF) containing polyhydroxy groups and its application in improving the fire performance of PLA composites in combination with ammonium polyphosphate (APP). The flame retardant evaluation revealed that the presence of 1.7% Ni-MOF and 3.3% APP in PLA increased the LOI value to 31.0%, upgraded the UL-94 level to V-0, decreased the peak heat release rate (pHRR), total heat release (THR) and total smoking production (TSP) by 27%, 19% and 50%, respectively, and substantially delayed the time to ignition (TTI) from 67 to 97 s. It was proposed that the flame retardants take effect in both vapor and condensed phases, and Ni-MOF nanosheets can synergistically improve the flame resistance of PLA with APP. The incorporation of Ni-MOF effectively inhibited the deterioration of mechanical properties for PLA composites caused by the presence of APP. • The Ni-MOF nanosheets containing polyhydroxy groups was prepared. • APP and Ni-MOF nanosheets significantly improved the fire safety of PLA composite. • The possible synergistic flame-retardant mechanism of Ni-MOF and APP was proposed. • Ni-MOF effectively improved the mechanical properties of PLA composites. [ABSTRACT FROM AUTHOR]

A novel nanocomposite was prepared from ethylene-co-vinyl acetate copolymer (EVA) and poly-3-hydroxy butyrate-co-valerate (PHBV) in combination with small amounts of [60]Fullerene (C 60). The thermal degradation as well as the incorporation effect of C 60 on the thermo-oxidative decomposition of EVA/PHBV/C 60 nanocomposites was investigated using thermogravimetric analysis (TGA). In order to assess the level of stabilization of nanocomposites, the oxidation induction time test was also determined. The obtained results indicated that the dispersion of C 60 even at low loading (0.3, 0.5 and 0.7 wt.%) exerts a significant increase on the thermal stability properties of nanocomposite. The oxidation induction time values of nanocomposites were remarkably increased with the increase of C 60 amounts. Surprisingly, the oxidation induction time of EVA/PHBV/C 60 (0.3 wt.%) is 1643 s higher than that of unfilled EVA/PHBV blend. The flammability properties investigated in pyrolysis combustion flow calorimetry (PCFC) showed that the addition of C 60 could prolong the time to peak of Heat Release Rate (pHRR) of around 30 °C compared to EVA/PHBV blend. It was demonstrated that C 60 is inhibitor of the thermal and thermo-oxidative degradation of EVA/PHBV blend. • The impact of C 60 on the thermal stability of EVA/PHBV blend is studied. • The incorporation of C 60 retard the decomposition process of nanocomposites. • Smaller C 60 amounts increase the decomposition temperatures of nanocomposites. • C 60 reacts with free radicals that are forming during oxidation. • C 60 reaction with free radical protects nanocomposites from decomposition. [ABSTRACT FROM AUTHOR]

• The multifunctional cyclotriphosphazene-based epoxy resin HGPCP was synthesized. • Non-isothermal curing kinetics of HGPCP/DDM and HGPCP/DDS were studied by DSC. • The thermal stability of cured HGPCP was higher than that of DGEBA. • The HGPCP thermosets possess excellent flame retardancy. The cyclotriphosphazene-based multi-functional epoxy resin hexa-[4-(glycidyloxymethyl)phenoxy]-cyclotriphosphazene (HGPCP) was designed and synthesized from commercial available hexachlorocyclotriphosphazene (HCCP). The chemical structure of HGPCP was characterized by fourier transform infrared (FTIR) spectroscopy, 1H, 13C and 31P NMR spectroscopy. Curing reaction of HGPCP with diamino diphenyl methane (DDM), diamino diphenyl sulfone (DDS) was investigated by non-isothermal differential scanning calorimetry (DSC), two-parameter autocatalytic equations of Šesták-Berggren were constructed to described the curing reaction rate quantitatively. Glass transition temperatures (T g) of HGPCP/DDM and HGPCP/DDS were 191 °C and 196 °C, respectively, which were higher than that of DGEBA/DDM (156 °C), and the cured HGPCP systems had better thermal stability than DGEBA thermoset. The flame retardant properties of HGPCP/DDM and HGPCP/DDS were investigated by limiting oxygen index (LOI), vertical burning test (UL-94), the results revealed that cured HGPCP thermoset successfully passed UL-94 V-0 flammability rating with LOI values above 30%, indicating that HGPCP possessed excellent flame retardancy. Furthermore, HGPCP/DDM and HGPCP/DDS both have higher tensile strength than DGEBA/DDM, while the failure strains were lower than DGEBA/DDM which may due to the much higher cross-linking densities. [ABSTRACT FROM AUTHOR]