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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]

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]

The synergistic effect and mechanism of the spherical CoSn(OH)6 (T-CHS) and ammonium polyphosphate (APP) on epoxy resin (EP) were investigated by limiting oxygen index (LOI), vertical combustion test (UL-94), cone calorimeter, tensile machine, thermogravimetric analysis-coupled with a Fourier transform infrared spectrometer (TGA/FTIR), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, and Raman spectrometer. The results indicate that when the mass ratio of APP and T-CHS is 5.9:0.1 and 5.5:0.5, respectively, there is a synergistic effect between APP and T-CHS, and the flame retardant EP samples could pass the V-0 level of UL-94 test and their tensile properties have little difference to that of the blank EP. Compared with the blank EP, the total heat release and total smoke production of EP/5.9APP/0.1 T-CHS are decreased by 25% and 26%, respectively. TGA/FTIR results of the EP samples under N2 atmosphere indicate the NH3 production of EP/5.9APP/0.1 T-CHS is decreased by 47% and the CO2 and H2O production is increased by 991% and 210%, respectively, when compared with that of the blank EP. APP and T-CHS show a good synergistic effect on promoting the retention of C, Co, Sn, and N elements in the char residues. The char residues of EP/5.9APP/0.1 T-CHS and EP/5.5APP/0.5 T-CHS samples contain Co3O4, CoO, SnO, SnO2, oxides of phosphorus, and Sn element, which form a more compact physical barrier. [ABSTRACT FROM AUTHOR]

The more efficient and hydrophobic modificated ammonium polyphosphate (M-APP) and charring agent (M-CA) were prepared based on sol–gel method, and they were used in the preparation of water-resistant and flame-retardant polypropylene (PP) composites. The results showed that the contact angles of M-APP and M-CA were 135.11° and 137.89°, respectively. The flame-retardant and thermal properties of the PP composites were also studied. The results showed that the flame retardancy of PP loaded with 30 mass% intumescent flame retardant (M-APP/M-CA = 3:1) was significantly increased. The limiting oxygen index (LOI) reached 36.8% and passed UL-94 V-0. The peak heat release rate and total heat release of the PP composite decreased from 1011.77 to 134.43 kW·m−2 and 100.58 to 6.86 MJ·m−2, respectively. The peak smoke production rate and total smoke release decreased from 0.13 to 0.0056 m2·s−1 and 1453.09 to 74.82 m2·m−2. The PP composite with M-APP/M-CA = 3:1 also exhibited excellent water resistance, and it could still reach UL-94 V-0 after soaking in 70 ℃ water for 168 h. [ABSTRACT FROM AUTHOR]

Rigid polyurethane foam/aluminum diethylphosphinate (RUPF/ADP) composites were prepared by one-step water-blown method. Furthermore, scanning electron microscope (SEM), thermal conductivity meter, thermogravimetric analysis (TGA), limiting oxygen index, Underwriters Laboratories vertical burning test (UL-94) and microsacle combustion calorimetry were applied to investigate thermal conductivity, thermal stability, flame retardancy and combustion behavior of RPUF/ADP composites. Thermogravimetric analysis–Fourier transform infrared spectroscopy (TG–FTIR) was introduced to investigate gaseous products in degradation process of RPUF/ADP composites, while SEM and X-ray photoelectron spectroscopy were used to research char residue of the composites. It was confirmed that RPUF/ADP composites presented well cell structure with density of 53.1–59.0 kg m−3 and thermal conductivity of 0.0425–0.0468 W m−1 K−1, indicating excellent insulation performance of the composites. Flame retardant test showed that ADP significantly enhanced flame retardancy of RPUF/ADP composites, RPUF/ADP30 passed UL-94 V-1 rating with LOI of 23.0 vol%. MCC test showed that ADP could significantly decrease peak of heat release rate (PHPR) of RPUF/ADP composites. PHPR value of RPUF/ADP20 was decreased to 158 W g−1, which was 21.8% reduced compared with that of pure RPUF. TG–FTIR test revealed that the addition of ADP promoted the release of CO2, hydrocarbons and isocyanate compound in first-step degradation of RPUF matrix while inhibited the release of CO in second step degradation. Char residue analysis showed that the addition of ADP promoted polyurethane molecular chain to form aromatic and aromatic heterocyclic structure, enhancing strength and compactness of the char. This work associated a gas–solid flame retardancy mechanism with the incorporation of ADP, which presented an effective strategy for preparation of flame retardant RPUF composites. [ABSTRACT FROM AUTHOR]

Different types of phosphorus containing halogen-free flame retardants (FRs) were added to an epoxy-dicyandiamide resin formulation in order to study to which extent they affect its glass transition temperature (Tg), tensile properties, thermal stability and burning behavior of the resin. For this purpose, an additive-type FR (ammonium polyphosphate encapsulated in melamine resin, MAPP) and two reactive-type FRs i) a commercial epoxy resin pre-reacted with 9,10-dihydro-oxa-10-phosphaphenanthrene-10-oxide, (DOPO), and ii) a phosphorus containing hardener (poly(m-phenylene methylphosphonate), (PMP) were used. It was observed that the addition of additive-type FR did not affect in great extent the Tg and provided a V-0 rating in UL94 test at low loadings. The addition of reactive-type FRs (DOPO and/or PMP), however, modified the structure of the chain network resulting in lower crosslink density as a consequence of their higher equivalent mass, but achieving also with low PMP content V-0 rating. [ABSTRACT FROM AUTHOR]

This article mainly studies the flame retardant and thermal degradation properties of thermoplastic polyurethane (TPU) composites based on HGM@[EOOEMIm][BF4], prepared by modifying hollow glass microsphere (HGM) with ionic liquid [EOOEMIm][BF4]. The physical and chemical characteristic of HGM@[EOOEMIm][BF4] was tested by X-ray photoelectron spectroscopy and scanning electron microscope-energy-dispersive spectrometer, respectively. And then the flame retardant and thermal degradation characteristics of all TPU composites were tested using smoke density test (SDT), cone calorimeter test (CCT) and thermogravimetric/fourier transform infrared spectroscopy, etc. The SDT results showed that HGM@[EOOEMIm][BF4] can significantly decrease the amount of smoke production. The CCT revealed that HGM@[EOOEMIm][BF4] can greatly enhance the flame retardant of TPU. The peak heat release rate value decreased from 1224.0 kW m−2 (TPU0) to 498.5 kW m−2 (TPU/HB2). The TG test showed that HGM@[EOOEMIm][BF4] can improve the thermal stability of TPU composites and promote the char formation in the combustion process of TPU. All results confirmed that HGM@[EOOEMIm][BF4] can make a great influence on the combustion and degradation of TPU. [ABSTRACT FROM AUTHOR]

A series of quaternary hybrid kenaf (K) flour-PP nanocomposites, such as PP/KF/MAPP/GNP/MgOH (K-GNP-MgOH), PP/KF/MAPP/GNP/APP (K-GNP-APP) and PP/KF/MAPP/GNP/MgO (K-GNP-MgO) filled with exfoliated graphene nanoplatelets (GNP)-3 phr acting as adjuvant in combination with mineral flame retardants, 20 mass/% magnesium hydroxide (Mg (OH)2) and 20 mass/% magnesium oxide (MgO), and 20 mass/% intumescent ammonium polyphosphate (APP), respectively, were prepared through melt extrusion using co-rotating twin screw extruder. The resulting quaternary nanocomposites were characterized in terms of flame retardancy, thermomechanical, thermal conductivity, thermal behavior, heat deflection temperature (HDT), and mechanical, morphological and structural properties. Mass loss calorimeter data revealed a significant reduction of peak heat release rate, total heat release, effective heat of combustion, mass loss rate and delayed time to ignition due to GNP-MgOH, GNP-MgO and GNP-APP synergistic mechanism in hybrid nanocomposites, respectively. The effective thermal conductivities and HDT of quaternary nanocomposites were found to significantly increase. DSC results revealed enhanced crystallization temperatures with reduced degree of crystallinity, while melting points remained stable. [ABSTRACT FROM AUTHOR]

Polyelectrolyte complexes (PECs) with nanocrystalline cellulose and ammonium polyphosphate (NCC/APP) were prepared by an accessibly oriented self-assembly method, and the morphology and ultrastructure were investigated with transmission electron micrographs, scanning electric microscopy, Fourier infrared, and X-ray diffraction. The prepared PECs were then used as a flame-retardant system in rice straw-HDPE composites (RPC), and the thermal degradation, flame retardancy, and mechanical properties were studied by thermogravimetry, cone calorimetry, limited oxygen index (LOI) and mechanical testing. The thermal stability and flame retardancy of RPC were significantly influenced with an incorporation of PECs. PECs can promote the thermal degradation of RPC that take place earlier and stabilize the char residues. PECs can significantly improve the LOI of RPC, and LOI increased to 24.8% and 25.0% in the presence of NCC1/APP and NCC5/APP. PECs had a slight effect on heat release rate. PECs can also improve the mechanical property of RPC, and the tensile and flexural strength were increased with the addition of PECs of NCC/APP. [ABSTRACT FROM AUTHOR]

Hard wood-polymer composite (HWC) was prepared, based on hot press technique, by mixing air-dried rice straw waste as a filler into a molten of chemically recycled extended polystyrene foam waste (PS) and its maleated form (PS-g-MA) as a matrix. Two fire retardants (FRs), namely zinc borate (ZB) and/or anhydrous magnesium hydroxide (MH), were dispersed into the composite to compensate for the poor thermal stability and flammability of the composite. Thermal properties of the reached HWC were evaluated by different techniques including thermogravimetric analysis, differential scanning calorimetric, in addition to, flammability analyses. Mechanical characterization was, also, rated based on tensile strength and elongation at break measurements. It was found that incorporation of the nominated fire retardants improved the thermal stability of the final products. Besides, flammability resistance was enhanced as ZB and/or MH was added to the hard wood-polymer composite formulation. The onset temperature of degradation and mass loss rates were significantly reduced in the presence of the FRs. The tensile strength of HWC was reinforced by marked additions of the FRs. The obtained data can fulfill the required optimal performance of the HWC to fire and mechanical characterizations which are necessary for many applications in the residential construction, transportation and furniture industries. [ABSTRACT FROM AUTHOR]

The isothermal oxidation process of red phosphorus (RP) was investigated by thermogravimetric analysis in the temperature range of 320-480 °C. The model-free, model-fitting and reduced-time plot methods were used to research the oxidation kinetics of RP. According to the d α/d t − α and model-free curves in different temperatures, the oxidation temperatures are divided into two ranges: lower temperatures (320-380 °C) and higher temperatures (390-410 °C). The apparent activation energy and oxidation controlling mechanisms in different temperature ranges are obtained. Besides, the trend of the oxidation rate with mass loss or temperature ranges is discussed. [ABSTRACT FROM AUTHOR]

In this study, silica sol (SiO sol) and KCO were used as flame retardants for wood. The synergistic effect of SiO sol and KCO on the flame retardancy, leaching resistance, and thermal properties of wood was investigated. The limiting oxygen index results revealed a significant improvement in the flame retardancy and leaching resistance of the wood sample treated with KCO and SiO sol using the double bath technique. The thermal analysis results showed that the synergistic effect of KCO and the SiO sol effectively prolonged the degradation of the wood sample during the charring stage and improved the stability of the char residue. The thermogravimetry-mass spectrometry analysis and scanning electron microscopy results showed that KCO catalyzed the degradation reaction of the wood sample at lower temperatures resulting in an increase in the water and carbon dioxide output, and the SiO sol formed a compact and melted barrier on the surface of the char residue, which hindered the transfer of heat and combustible gases in the condensed phase. Thus, the combination of KCO and SiO sol proves to be a promising flame-retardant system for wood. [ABSTRACT FROM AUTHOR]

Octavinylsilsesquioxane (OVS) as a flame retardant was firstly synthesized, and its structure was characterized by Fourier transform infrared spectroscopy and C and Si nuclear magnetic resonance. It was used to impart flame retardancy to polycarbonate (PC). The flame retardancy and flame-retarding mechanism of the PC/OVS composites were studied by limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimeter (CONE), TG and scanning electron microscopy. The decomposition activity energies of PC samples were studied by the equation of Kissinger. The results showed that PC/1 mass% OVS composites passed UL-94V-0 rating, and its LOI values were 29.4%. Compared with PC, for the PC/OVS composites, the thermal stability and the char yield are increased, but the rate of heat release and the total heat release are much decreased. Scanning electron microscopy revealed that the char properties had crucial effects on the flame retardancy. And the flame-retardant mechanism was also discussed. [ABSTRACT FROM AUTHOR]

An efficient flame retardant (TS-IFR) was designed by combining phosphoric acid, tea saponin (TS) and melamine structures into a single structure to improve both the mechanical properties and flame retardant performance of natural rubber (NR) composites. A char-forming agent, TS, was successfully modified through chemical method to prepare tea saponin-based intumescent flame retardant (TS-IFR). The structure of the TS-IFR was characterized by Fourier transform infrared spectroscopy and H-NMR. A series of flame retardant natural rubber (FRNR) composites were prepared by mixing TS-IFR with NR using a two-roll mill. The thermal stability and fire behaviors of these FRNR composites were investigated by thermogravimetric analysis, limiting oxygen index, vertical burning test (UL-94), cone calorimeter test and scanning electron microscopy. The results revealed that the mechanical properties and flame retardant behavior of NR/TS-IFR were significantly improved for both the high interfacial interaction of TS-IFR with NR matrix and effective dispersion of TS-IFR into NR matrix. As a result, TS-IFR can act as an efficient flame retardant in improving the fire properties of NR. [ABSTRACT FROM AUTHOR]

Influence of expandable graphite on flame retardancy and mechanical properties of organic-inorganic hybrid material based on sodium silicate and polyisocyanate has been investigated. The results of mechanical measurement show that adding expandable graphite decreases the maximum of the compressive strength from 5.98 to 1.49 MPa. The thermal property is evaluated by thermal conductivity test, thermogravimetric analysis. The results indicate that adding the expandable graphite increases thermal conductivity of composite and lowers maximum heat release rate. The material with expandable graphite has better flame retardancy than original material with an obvious decrease in heat release rate, fire spread and thermal decomposition rate. What is more, intumescent graphite has the obvious effect to suppress flame and prevent the composite from fire. Scanning electron microscope shows that many large particles and gaps appear after compression deformation. [ABSTRACT FROM AUTHOR]

To improve the flame-retardant properties of polymer materials, an organic-inorganic hybrid material was obtained by various mixed ratios of sodium silicate solution and polyisocyanate. The chemical structure of materials was characterized by Fourier transform infrared spectroscopy, and the microstructures were observed by scanning electron microscope. The influence of various ratios of polyisocyanate and sodium silicate on the flame-retardant properties of hybrid materials was emphatically investigated. The results showed that Si-O and Si-O-Si bonds were introduced into the hybrid materials and the surfaces were rougher than that of rigid polyurethane. The hybrid materials had better flame-retardant properties than the rigid polyurethane with an obvious decrease in heat release rate, spread rate of fire, decomposition rate and increase in residue and LOI value. When the hybrid materials were burning, less carbon dioxide and carbon monoxide were produced. In addition, the TG curve showed that the mass of hybrid materials decreased more slowly than the mass of the rigid polyurethane. So the hybrid materials showed excellent flame-retardant properties. [ABSTRACT FROM AUTHOR]

Flame-retardant glass fiber-reinforced PA6 (GFPA6) composites were prepared by incorporating the mixture of piperazine pyrophosphate (PAPP) and aluminum hypophosphite (AHP) into GFPA6. From the results of UL-94 test, limiting oxygen index (LOI) and microscale combustion calorimetry (MCC) tests, the as-obtained composites exhibited significantly enhanced flame retardancy including higher LOI values, better UL94 rating (V-0 for 18.0 mass% PAPP/AHP mixture), and decreased peak heat release rate and total heat release. And PA6-4 with a 4/1 mass ratio of PAPP to AHP reached the highest LOI value. The influence of PAPP/AHP on the decomposition pathway of GFPA6 was discussed based on TG and TG-FTIR analysis. The interaction between PAPP/AHP and GFPA6 altered the decomposition pathway of GFPA6 resulting in the formation of compact char layer, high thermal stability within high-temperature region, and weak intensities of a variety of pyrolysis gas products. Meanwhile, the thermomechanical property data revealed the storage modulus of samples were increased with increasing PAPP/AHP content, whereas the glass transition temperatures were reduced gradually. Moreover, the results of scanning electron microscope illustrated that the introduction of PAPP/AHP mixture can promote the formation of compact char layer and change the surface element composition of the char. [ABSTRACT FROM AUTHOR]

To improve both the mechanical properties and flame-retardant performance of flame-retardant natural rubber composite, double-shell co-microencapsulated ammonium polyphosphate and expandable graphite (EG) (M(A&E)) were prepared by using melamine-formaldehyde resin and organic silicon in situ polymerization. The structure of the microcapsules was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Due to the presence of synergists EG and organic silicone shell, the NR/M(A&E) composites had much better flame-retardant and mechanical properties than other flame-retardant NR composites. The limited oxygen index value of the NR/M(A&E) composite reached the maximum, and the UL-94 ratings were increased to V-0; in addition, the cone calorimetry indicates that the NR/M(A&E) composite has best flame-retardant properties and the lowest fire risk. Furthermore, the improvement in mechanical properties and flame-retardant behavior of M(A&E) particles filled NR were attributed to the desirable dispersion by the RPA. The occurrence of a synergistic effect between EG and intumescent flame-retardant in the NR composites was proved. As a result, the thermal stability and flame retardancy of NR were enhanced compared to the NR system. [ABSTRACT FROM AUTHOR]

A new series of four different linear aliphatic ether linked aromatic bismaleimides (AEBMIs) were synthesized from the respective linear aliphatic ether-linked aromatic diamines and maleic anhydride. Further, the POSS-AEBMI nanocomposites were developed by Michael addition reaction of bismaleimide with varying mass percentages of octa(aminophenyl)silsesquioxane and were characterized by the fourier transform infrared spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Data from thermal studies revealed that the POSS-reinforced AEBMI nanocomposites possesses higher glass transition temperature ( Tg), thermal stability, limiting oxygen index, and lower dielectric constant when compare to that of neat AEBMI. X-ray diffraction and transmission electron microscopy analysis confirmed the molecular level dispersion of POSS in the AEBMI matrix. [ABSTRACT FROM AUTHOR]

Ethyl cellulose, a widely used bio-degradable shell material, microencapsulated ammonium polyphosphate (MAPP) was added to the bio-degradable poly(butylene succinate) (PBS) to improve its flame retardancy, compatibility, and thermal stability. The MAPP was well characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy (SEM), water contact angle, and thermogravimetric (TG) analysis. The SEM results indicate the improved dispersion of MAPP into PBS matrix and the formation of the strong interfacial adhesion between MAPP and PBS than APP. With the incorporation of MAPP and char-forming agent into PBS, the limiting oxygen index of the composite was increased to 35.5 %, and the sample can pass the UL-94 V-0 rating, while the un-microencapsulated counterpart cannot reach the rating. The cone calorimeter test showed that the peak heat release rate was decreased by 46.7 % and the burning time was also prolonged compared to the pure PBS. The increased melt flow index and rheology test indicated the increase of viscosity and the improvement of anti-dripping properties. Moreover, the mechanical properties and thermal stability of MAPP composite were also obviously enhanced after the microencapsulation by mechanical, dynamical mechanical thermal analysis, and TG analysis. [ABSTRACT FROM AUTHOR]

The curing behaviour of 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexane carboxylate was investigated by the dynamic differential scanning calorimetry (DSC) using phosphorus-containing poly(amide-imide)s (PAIs) having free amine groups, 4,4′-diaminodiphenylmethane (PM) and p-phenylenediamine (PA), in the ratio of 1:1. The PAIs were prepared by co-polymerization of diimide-diacid (DIDA) and phosphorus-containing triamines having phenylene moiety. l-Tryptophan and pyromellitic anhydride were used to synthesize DIDA. Triamines used in the synthesis PAIs were tris(3-aminophenyl) phosphine (TAP), tris(3-aminophenyl) phosphine oxide (TAPO) and bis(3-aminophenyl) aminotolyl phosphine (BAP). TAP-, TAPO- and BAP-containing PAIs were designated as PTAP, PTAPO and PBAP, respectively. These PAIs with free amine groups were characterized by FTIR, H NMR, C NMR spectroscopic techniques and elemental analysis. The mixture of PAIs and PM or/and PA in the ratios of 0:1, 1:0 and 0.5:0.5 was used for investigation. DSC was used to study the curing of epoxy by recording the DSC scans at heating rates of 10 °C min. Thermal stability of epoxy resin cured isothermally was evaluated by recording thermo gravimetric traces in nitrogen atmosphere at the heating rate of 20 °C min. All samples are highly stable, and the 10 % mass loss found was in the range of 335-520 °C. The percent char yield was highest in case of resin sample E/PM/PTAPO. The flame-retardant properties of cured epoxy resins were investigated by the limiting oxygen index test (LOI) and UL94 test. When phosphorus was incorporated in epoxy resin, the epoxy resin system met the UL94 V-0 classification and the LOI reached at 37.8, because of nitrogen-phosphorus synergistic effect. [ABSTRACT FROM AUTHOR]

This paper presents the results of investigating the thermal stability, flammability, and fire hazard of cross-linked EVM/NBR blends unfilled and filled with halogenless flame-retardant compounds such as melamine cyanurate or magnesium hydroxide. The thermal analysis of the blends was carried out in the atmosphere of air. The activation energy of the composite destruction was determined by two non-isothermal methods: Flynn-Wall-Ozawa's and Kissinger's methods. The flammability of the composites obtained was determined by the method of oxygen index and on the basis of their combustion in air. The fire hazard of the vulcanizates investigated was determined with the use of a cone calorimeter and on the basis of toxicometric parameters W. The test results have shown that the flame retardants used increase the thermal stability of the cross-linked blends and decrease their flammability, and thereby allow one to obtain self-extinguishing or non-flammable polymeric materials. The cross-linked EVM/NBR blends filled with these flame-retardant compounds are characterized by good mechanical properties and reduced fire hazard. [ABSTRACT FROM AUTHOR]

The thermal properties of paraffin as phase change material (PCM), combined with layered zinc hydroxide nitrate (LZHN) and intumescent flame retardant (IFR), have been studied by thermogravimetric analysis (TG), TG-Fourier transform infrared spectrometry (TG-FTIR), cone calorimeter (CONE),and differential scanning calorimetry (DSC). The TG results indicated that the thermal stabilities of the paraffin and paraffin/IFR composites could be improved when dodecyl sodium sulfate-modified LZHN (ds-LZHN) was incorporated. The TG-FTIR results indicated that ds-LZHN could reduce the release of combustible gases for paraffin and paraffin/IFR. The CONE results showed that the flame-retardant efficiency of IFR could be improved in the paraffin/IFR system owing to ds-LZHN. DSC results presented that the phase change temperatures and latent heats of the composites were determined by the dispersed paraffin with their mass percentage. [ABSTRACT FROM AUTHOR]

The honeycomb structure has superior compressive strength so that it is being utilized in various fields. In addition, the paper honeycomb has excellent economic feasibility because of its low production cost and has an environment-friendly advantage because its recycling is possible. Securing of flame retardant performance is essential to use it as interior materials of buildings and fireproof doors using the advantage like this. The present research has evaluated combustion and thermal properties according to flame retardant treatment in terms of two kinds of specimens when flame retardant film is attached to paper honeycomb, and when paper honeycomb is impregnated to flame retardant agents. As a result of evaluating flame retardant performance utilizing a cone calorimeter, the case impregnated into flame retardant agents showed the most superior flame retardant performance. Through this result, it was confirmed that the paper honeycomb can be utilized as interior materials of buildings though improvement of flame retardant performance. [ABSTRACT FROM AUTHOR]

The effect of three flame retardants, KCO, NaSiO·9HO, and NaBO·10HO on the process and composition of volatile products of the thermal degradation of wood has been investigated by the thermogravimetric (TG), differential thermogravimetry (DTG), differential thermal analysis (DTA), and the synchronous thermogravimetry-mass spectrometry (TG-MS) analysis methods. The results showed that the ion current intensity and ion peak area of m/ z = 18 and 44 MS signals were increased by the flame retardants but the ion peak area of m/ z = 28 MS signal was decreased (except KCO) at the meantime. What's more, the ion current intensity and ion peak area of m/ z = 60 and 68 MS signals were also decreased (except KCO), which mean that NaBO can significantly enhances the dehydration and inhibits the depolymerization of wood. Although KCO accelerates the dehydration reaction, it cannot inhibit the depolymerization reaction effectively, so the flame retardant efficiency of KCO is decreased with the higher concentration. The catalysis of dehydration reaction of NaSiO is the worst one. [ABSTRACT FROM AUTHOR]

novel silicon-containing trifunctional cycloaliphatic epoxide resin tri(3,4-epoxycyclohexylmethyloxy) phenyl silane (TEMPS) was synthesized and characterized by FTIR, H NMR, C NMR, and Si NMR spectroscopic analysis. A series of flame-retardant formulations by blending TEMPS with a commercial epoxide resin DGEBA (EP828) in different ratios were prepared, and exposed to a medium pressure lamp to form the cured films in the presence of diaryliodonium hexafluorophosphate salt as a cationic photoinitiator. The thermal degradation behaviors of the cured films were evaluated by thermogravimetric analysis. The char yields under nitrogen and air atmospheres increased along with the TEMPS content. The limiting oxygen index (LOI) value increased from 22 for EP828 to 30 for TEMPS80, demonstrating the improved flame retardancy. The data from the dynamic mechanical thermal analysis showed that TEMPS had good miscibility with EP828. The T and T both decreased from 93 and 138 to 78 and 118 °C, respectively. The crosslinking density ( ν) increased along with the TEMPS content. The mechanical property measurements indicated that the addition of TEMPS led to a decrease in the tensile strength and an increase in the elongation-at-break. [ABSTRACT FROM AUTHOR]