Synthesis of novel triazine charring agent and its effect in intumescent flame‐retardant polypropylene

A novel charring agent (CNCA‐DA) containing triazine and benzene ring, using cyanuric chloride, aniline, and ethylenediamine as raw materials, was synthesized and characterized. The effects of CNCA‐DA on flame retardancy, thermal degradation, and flammability properties of polypropylene (PP) were investigated by limited oxygen index (LOI), vertical burning test (UL‐94), thermogravimetric analysis (TGA), and cone calorimeter test (CCT). The TGA results showed that CNCA‐DA had a good char forming ability, and a high initial temperature of thermal degradation; the char residue of CNCA‐DA reached 18.5% at 800°C; Ammonium polyphosphate (APP) could improve the char residue of APP/CNCA‐DA system, the char residue reached 31.6% at 800°C. The results from LOI and UL‐94 showed that the intumescent flame retardant (IFR) containing CNCA‐DA and APP was very effective in flame retardancy of PP. When the mass ratio of APP and CNCA‐DA was 2 : 1, and the IFR loading was 30%, the IFR showed the best effect; the LOI value reached 35.6%. It was also found that when the IFR loading was only 20%, the flame retardancy of PP/IFR can still pass V‐0 rating in UL‐94 tests, and its LOI value reached 27.1%. The CCT results demonstrated that IFR could clearly change the decomposition behavior of PP and form a char layer on the surface of the composites, consequently resulting in efficient reduction of the flammability parameters, such as heat release rate (HRR), total heat release (THR), smoke production rate (SPR), total smoke production (TSP), and mass loss (ML). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synergistic effects of expandable graphite with magnesium hydroxide on the flame retardancy and thermal properties of polypropylene

In this study, the flammability characterization and synergistic effects of different particle size of expandable graphite (EG) with modified magnesium hydroxide (MH) in flame‐retardant polypropylene (PP) composites were studied by limiting oxygen index (LOI), UL‐94 test, thermogravimetric analysis (TGA), and fourier transform infrared (FTIR) spectroscopy. The results showed that the particle size of EG had a great effect on the flammability of the PP/MH/EG composites. The EG2 with smaller particle size could apparently increase the LOI value and improved the UL‐94 flammability properties rating of the PP composites. The data obtained from the TGA and FTIR curves indicated that the thermo‐oxidative stability of PP/MH/EG composites increased with decreasing particle size of EG. And the smaller the particle size of EG, the higher the residues of the composite. POLYM. ENG. SCI., 47:1756–1760, 2007. © 2007 Society of Plastics Engineers     

Synergism between hydrotalcite and silicate‐modified expandable graphite on ethylene vinyl acetate copolymer combustion behavior

Influence of independent Mg–Al‐layered double hydroxide (LDH), silicate modified expandable graphite (EG), mixture of LDH and EG at various ratios on ethylene vinyl acetate copolymer (EVA) combustion behavior and thermal stability was detected in sequence through the limiting oxygen index (LOI), vertical combustion (UL‐94) level, microscale combustion calorimeter (MCC) tests and thermal gravimetric/differential thermal gravimetric (TG/DTG) analysis. Results show that the 30 wt % LDH can improve the LOI of 70EVA/30LDH to 27.0%, but the combustion accompanies with serious melt‐dropping. While, the same amount of the EG can increase the LOI, UL‐94 level to 28.5%, V‐0 respectively. However, the combination of LDH and EG can further enhance the 70EVA/20LDH/10EG flame retardancy, it presents the LOI of 29.7%, UL‐94 level of V‐0, and total heat release of 29.5 kJ g^?1. The excellent flame retardancy is attributed to its compact residue. Compared with residue mass, the residue compactness plays a more important role in improving flame retardancy. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44634.     

Combustion characteristics and synergistic effects of red phosphorus masterbatch with expandable graphite in the flame retardant HDPE/EVA composites

In this work, the flammability behaviors and synergistic effects of red phosphorus masterbatch (RPM) with expandable graphite (EG) in flame‐retardant high‐density polyethylene/ethylene vinyl‐acetate copolymer (HDPE/EVA) composites have been investigated by limiting oxygen index (LOI), UL‐94 test, cone calorimeter test (CCT), thermogravimetric analysis (TGA), Fourier‐transform infrared (FTIR) and scanning electron microscopy (SEM). The data obtained from LOI, UL‐94 test and CCT showed that suitable amount of RPM had synergistic effects with EG in the HDPE/EVA/EG/RPM composites. The addition of RPM greatly increased the LOI values by 3.4%, obtained UL‐94 V‐0 rating, decreased the heat release rates and total heat release, and prolongated the ignition time when 6.7 phr RPM substituted for EG in the HDPE/EVA/EG/RPM composites. The data from TGA and FTIR spectra also indicated the synergistic effects of RPM with EG considerably enhanced the thermal degradation temperatures. The morphological observations after UL‐94, CCT, and SEM images presented positive evidences that the synergistic effects took place for RPM with EG, and the flame‐retardant mechanism has been changed in flame‐retardant HDPE/EVA/EG/RPM composites. The formation of stable and compact charred residues promoted by RPM acted as effective heat barriers and thermal insulations, which improved the flame‐retardant performances and prevented the underlying polymer materials from burning. POLYM. ENG. SCI., 55:2884–2892, 2015. © 2015 Society of Plastics Engineers     

Flame retarded epoxy resins by adding layered silicate in combination with the conventional protection‐layer‐building flame retardants melamine borate and ammonium polyphosphate

The pyrolysis and flammability of phosphonium‐modified layered silicate epoxy resin nanocomposites (EP/LS) were evaluated when LS was combined with two flame retardants, melamine borate (MB) and ammonium polyphosphate (APP), that also act via a surface protection layer. Thermogravimetry (TG), TG coupled with Fourier Transform Spectroscopy (TG‐FTIR), oxygen index (LOI), UL 94 burning chamber (UL 94) and cone calorimeter were used. The glassy coating because of 10 wt % MB during combustion showed effects in the cone calorimeter test similar to nanodispersed LS, and somewhat better flame retardancy in flammability tests, such as LOI and UL 94. Adding APP to EP resulted in intumescent systems. The fire retardancy was particularly convincing when 15 wt % APP was used, especially for low external heat flux, and thus, also in flammability tests like LOI and UL 94. V0 classification is achieved when 15 wt % APP is used in EP. The flame retardancy efficiency of the protection layers formed does not increase linearly with the MB and APP concentrations used. The combination of LS with MB or APP shows antagonism; thus the performance of the combination of LS with MB or APP, respectively, was disappointing. No optimization of the carbonaceous‐inorganic surface layer occurred for LS‐MB. Combining LS with APP inhibited the intumescence, most probably through an increase in viscosity clearly above the value needed for intumescent behavior. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Flammability and thermal degradation of intumescent flame‐retardant polypropylene composites

The flammability of polypropylene (PP) composites containing intumescent flame‐retardant additives, i.e., melamine pyrophosphate (MPP) and 1‐oxo‐4‐hydroxymethyl‐2,6,7‐trioxa‐1‐phosphabicyclo[2.2.2]octane (PEPA) was characterized by limiting oxygen index (LOI), UL 94 test, and cone calorimeter. In addition, the thermal degradation of the composites was studied using thermogravimetric analysis (TG) and real‐time Fourier transform infrared (RTFTIR). It has been found that the PP composite only containing MPP (or PEPA) does not show good flame retardancy even at 30% additive level. Compared with the PP/MPP binary composite, the LOI values of the PP/MPP/PEPA ternary composites at the same additive loading are all increased, and UL 94 rating of the ternary composite (PP3) studied is raised to V‐0 rating from no rating (PP/MPP). The cone calorimeter results show that the heat release rate of some ternary composites decreases in comparison with the binary composite. It is noted from the TG data that initial decomposition temperatures of ternary composites are lower than that of the binary composites. The RTFTIR study indicates that the PP/MPP/PEPA composites have higher thermal oxidative stability than the pure PP. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers     

Thermal degradation behaviors and flame retardancy of epoxy resins with novel silicon‐containing flame retardant

A novel macromolecular silicon‐containing intumescent flame retardants (Si‐IFR) was synthesized, and its structure was a caged bicyclic macromolecule containing phosphorus‐silicon characterized by IR. Epoxy resins (EP) were modified with Si‐IFR to get the flame retardant EP, whose flammability and burning behavior were characterized by UL 94 and limiting oxygen index (LOI). Twenty percentage of weight of Si‐IFR was doped into EP to get 27.5% of LOI and UL 94 V‐0. The degradation behavior of the flame retardant EP was studied by thermogravimetry, differential thermogravimetry, scanning electron microscopy, and X‐ray photoelectron spectroscopy analysis. The experimental results exhibited that when EP/Si‐IFR was heated, the phosphorus‐containing groups firstly decompose to hydrate the char source‐containing groups to form a continuous and protective carbonaceous char, which changed into heat‐resistant swollen char by gaseous products from the nitrogen‐containing groups. Meanwhile, SiO₂ reacts with phosphate to yield silicophosphate, which stabilizes the swollen char. The barrier properties and thermal stability of the swollen char are most effective in resisting the transport of heat and mass to improve the flame retardancy and thermal stability of EP. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation of aluminum hydroxide/aluminum phosphinate flame‐retardant poly(vinyl alcohol) foam through thermal processing

A novel flame‐retardant poly (vinyl alcohol) (PVA) composite foam was prepared successfully through thermal processing, which was filled with high content of flame retardant, based on aluminum hydroxide (ATH) and aluminum phosphinate (AlPi) and using water as plasticizer and blowing agent. The flame‐retardant property and mechanism of the prepared foam matrix were studied by vertical burning test, limiting oxygen index (LOI), cone calorimeter, scanning electronic microscopy (SEM) and X‐ray photoelectron spectroscopy (XPS). The experimental results showed that the PVA/ATH/AlPi (1/1.2/0.05) composite achieved LOI value of 41% and UL94 V‐0 (3.2 mm) rate. The addition of ATH and AlPi into PVA matrix significantly decreased flammability of the composites, because a more compact and continuous char layer of the PVA/ATH/AlPi composite could be formed, due to the involvement of AlPi in the char‐forming reaction. Compared with the pure PVA sample, the peak heat release rate (PHRR) and total heat release (THR) of PVA/ATH/AlPi (1/1.2/0.05) composite were reduced by 76.5% and 58.2%, respectively. Built upon this PVA‐based foam matrix with good flame retardancy, the flame‐retardant PVA‐based foam was successfully prepared through thermal extrusion. In addition, the influence of water content on melt viscosity, foam structure and mechanical strength was also analyzed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42020.     

Synergistic flame retardant effect of cerium oxide in ethylene‐vinyl acetate/aluminum hydroxide blends

The flammability characterization and synergistic flame retardant effect of cerium oxide (CeO₂) in the ethylene‐vinyl acetate/aluminum hydroxide blends were studied using limiting oxygen index (LOI), UL‐94 test, and cone calorimeter test (CCT). The results showed that the addition of a given amount of CeO₂ apparently increased the LOI value and UL‐94 rating. The data obtained from the CCT indicated that the addition of CeO₂ greatly decreased the heat release rate and prolonged the combustion time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Thermal and combustion behavior of ethylene‐vinyl acetate/aluminum trihydroxide/Fe‐montmorillonite composites

The flammability characterization and synergistic flame‐retardant effect of Fe‐montmorillonite (Fe‐OMT) in the ethylene‐vinyl acetate/aluminum hydroxide (EVA/ATH) compounds were studied using limiting oxygen index (LOI), UL‐94 test, cone calorimeter, microscale combustion calorimetry (MCC), and thermogravimetric analysis (TGA). The results showed that addition of Fe‐OMT increases the LOI value and improves the UL 94 rating. Cone calorimeter data indicate that the addition of Fe‐OMT greatly reduced the heat release rate and carbon monoxide production rate. Furthermore a compact char residue formed on the surface of the sample with a suitable of Fe‐OMT during the combustion. The MCC results indicate that addition of Fe‐OMT reduced the heat release rate and catalyzed the decomposition of EVA. The TGA data showed further evidence that Fe‐OMT can catalyze carbonization reactions. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

A novel intumescent flame‐retardant epoxy resins system

Pentaerythritol diphosphonate melamine–dicyandiamide–formaldehyde resin salt, a novel macromolecular intumescent flame retardants (IFR), was synthesized, and its structure was a caged bicyclic macromolecule containing phosphorus characterized by IR, NMR and element analysis. The flame retardancy and thermal behavior of a new IFR system for epoxy resin were investigated by LOI, UL‐94 test, TG, and IR. Activation energy for the decomposition of samples was obtained using Kissinger equation. 25% of weight of IFR were doped into epoxy resin to get 27.5 of LOI and UL 94 V‐0. The TG curves and IR spectra show that IFR decreases the initial decomposition temperature and the maximum weight loss rate of epoxy resin, and enhances the thermal stability of epoxy resin at high temperatures and char yield. The activation energy for epoxy resin containing IFR was decreased by 44.8 kJ/mol, which shows that IFR can catalyze decomposition of epoxy resin. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Thermal degradation and flame retardance of epoxy resins containing a microencapsulated flame retardant

Two steps were used in the synthesis of a microencapsulated intumescent flame retardant (MIFR). First bis (1‐oxo‐2,6,7‐trioxa‐l‐phosphabicyclo[2.2.2]octane‐4‐methylol) phosphate melaminium salt (Melabis) was synthesized. Then the Melabis was encapsulated with melamine resin to obtain the MIFR. Its structure was characterized by XPS, SEM, and elemental analysis, and the factors affecting microencapsulation were identified and discussed. Epoxy resins (EP) were modified with the MIFR to prepare flame‐retardant EP, whose flammability and burning behavior were characterized by UL 94 and limiting oxygen index (LOI) tests. The microcapsules (20% by weight) were added to EP in order to achieve an LOI of 29.5% and a UL 94 rating of V‐0. The thermal properties of epoxy resins containing the MIFR were investigated by thermogravimetry (TG) and differential thermogravimetry (DTG). The FR decreased by weight loss, R_max (the maximum weight loss rate), and the thermal stability of EP while promoting the formation of an effective charring layer. The char structures were studied by SEM. J. VINYL ADDIT. TECHNOL., 2012. © 2012 Society of Plastics Engineers     

Synthesis of a novel flame retardant containing phosphorus and sulfur and its application in polycarbonate

A novel flame retardant containing phosphorus and sulfur, bis(2‐tienyl)phenylphosphine (BTPP) was synthesized and characterized with Fourier transform infrared spectroscopy, ¹H, ¹³C, and ³¹P nuclear magnetic resonance. BTPP was used to impart flame retardancy to polycarbonate (PC). Combustion behaviors and thermal degradation properties of PC/BTPP system were assayed by limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimeter test, and thermogravimetric analysis. PC/3 wt% BTPP passed UL‐94 V‐0 rating with 3.0 mm samples and the LOI value was 36.5%. PC/6 wt% BTPP passed UL‐94 V‐0 rating with 1.6 mm samples and the LOI value was 38.5%. Scanning electron microscopy revealed that char properties had direct effects on the flame retardancy. Mechanical properties and water resistance of PC/BTPP system were also examined. After water resistance test, PC/3 wt% BTPP with 3.0 mm samples and PC/6 wt% BTPP with 1.6 mm samples kept V‐0 rating and mass loss were only 0.2%. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

Effects of synthesis conditions on crystal morphological structures and thermal degradation behavior of hydrotalcites and flame retardant and mechanical properties of EVA/hydrotalcite blends

The effects of synthesis methods and reaction conditions on the crystal morphological structures and thermal degradation behavior of hydrotalcites have been studied by X‐ray diffraction (XRD), transmission electron microscopy (TEM), particle size analysis (PSA), and differential thermal analysis (DTA). The flame retardant and mechanical properties of ethylene–vinyl acetate (EVA) blends with the corresponding hydrotalcites have been estimated by limiting oxygen index (LOI), UL‐94, and mechanical measurements. The results from the XRD, TEM, and PSA demonstrate that the hydrotalcites synthesized by ultrasound method have larger crystal sizes and particle size distribution than those by mechanical stirring method. Higher reaction temperature, longer dripping time, and lower solution concentration can increase the crystal and particle sizes of ultrasound‐synthesized hydrotalcites, whereas the longer ultrasound aging time can increase the crystal sizes and decrease the particle sizes of hydrotalcites because of the smashing conglomeration. The DTA data give a positive evidence that the hydrotalcite samples prepared by mechanical stirring method with longer alkaline dripping time have higher thermal degradation temperature than those by ultrasound method, since the ultrasound‐synthesized hydrotalcites have more lattice defects than stirring‐prepared hydrotalcites. The data from LOI, UL‐94, and mechanical tests show that the ultrasonic‐synthesized hydrotalcites have better flame retardant properties, whereas the stirring‐synthesized hydrotalcites have better tensile strength in the EVA/hydrotalcite blends. POLYM. COMPOS., 28:131–138, 2007. © 2007 Society of Plastics Engineers     

Flame Retardancy and Thermal Performance of Polypropylene Treated With the Intumescent Flame Retardant,Piperazine Spirocyclic Phosphoramidate

Piperazine spirocyclic phosphoramidate (PSP), a novel halogen‐free intumescent flame retardant, was synthesized and used to improve the flame retardancy and dripping resistance of polypropylene (PP) combined with ammonium polyphosphate (APP) and a triazine polymer charring‐foaming agent (CFA). The optimum flame‐retardant formulation was PSP:APP:CFA = 3:6:2 (weight ratio). The flammability and thermal behavior of the (intumescent flame‐retardant)‐PP (IFR‐PP) were investigated via limiting oxygen index (LOI), vertical burning tests (UL‐94), thermogravimetric analysis, and cone calorimetry (CONE). The results indicated that the IFR‐PP had both excellent flame retardancy and anti‐dripping ability. The optimum flame‐retardant formulation gave an LOI value of 39.8 and a UL‐94 V‐0 rating to PP. Moreover, both the heat release rate and the total heat release of the IFR‐PP with the optimum formulation decreased significantly relative to those of pure PP, according to the cone calorimeter analyses. The residues of IFR‐PP obtained after CONE tests were observed by scanning electron microscopy, and it was found that the char yield was directly related to the flame retardancy and anti‐dripping behavior of the treated PP. J. VINYL ADDIT. TECHNOL., 20:10–15, 2014. © 2014 Society of Plastics Engineers     

木粉及聚磷酸铵对PE-HD木塑复合材料阻燃和力学性能的影响

以高密度聚乙烯(PE-HD)为基体,聚磷酸铵(APP)和木粉(WF)为膨胀型阻燃体系,制备了阻燃木塑复合材料(WPC)。通过极限氧指数、垂直燃烧UL 94、锥形量热分析、热失重分析、红外光谱分析、力学性能等对其进行性能表征。结果表明,与纯PE-HD相比,极限氧指数随着WF含量增加而提高,添加40 %WF时极限氧指数提高到30.5 %,UL 94可达V-0等级,热释放速率峰值和总热释放量降低;APP和WF燃烧过程中发生了化学作用,形成了保护炭层,提高了材料的热稳性,材料的拉伸和弯曲强度得到提高。     

Flame retardancy and mechanical properties of a novel intumescent flame‐retardant unsaturated polyester

A novel macromolecular intumescent flame retardant (MIFR) was synthesized. Unsaturated polyester (UP) filled with MIFR as flame‐retardant additive was prepared. The effects of MIFR on properties such as tensile strength, impact strength, flame‐retardant behavior, thermal stability, and morphology of char were studied. Its flammability and burning behavior were characterized by UL 94 and limiting oxygen index. Twenty‐four percent of MIFR were doped into UP to get 30.5% of limiting oxygen index and UL 94 V‐0, whereas its tensile strength and the impact strength were decreased by only 7.2% and 7.0%, respectively. Activation energy for the decomposition of samples was obtained by using the Kissinger equation. The results for UP containing MIFR, compared with UP, show that the weight loss, thermal stability, and the decomposition activation energy decreased, and the char yield increased, showing that MIFR can catalyze decomposition and carbonization of UP to form an effective charring layer to protect the underlying substrate. J. VINYL ADDIT. TECHNOL., 22:350–355, 2016. © 2014 Society of Plastics Engineers     

Effects of organopalygorskite on intumescent flame‐retarded polypropylene

The effect of organopalygorskite (OPGS) on an intumescent flame retardant (IFR) low‐density polypropylene (PP) has been investigated using the limited oxygen index (LOI), vertical burning test (UL‐94) and thermogravimetric analysis (TGA). The results of the LOI and UL‐94 tests indicate that the addition of OPGS substantially increases the LOI value for PP/IFR at a OPGS to IRF mass ratio of 2/28 with 30 wt% of total flame retardant. In addition, the samples pass the V‐0 rating in the UL‐94 tests. The results indicate that the addition of 2.0 wt% of OPGS simultaneously increases the tensile strength and bending strength of PP/IFR. J. VINYL ADDIT. TECHNOL., 24:281–287, 2018. © 2016 Society of Plastics Engineers     

Synthesis of a phenylene phenyl phosphine oligomer and its flame retardancy for polycarbonate

A novel flame retardant, phenylene phenyl phosphine oligomer (PPPO) was synthesized and its chemical structure was characterized using Fourier transform infrared spectroscopy, ¹H, ¹³C, ³¹P nuclear magnetic resonance spectroscopy and mass spectrometer. PPPO was used to impart flame retardancy to polycarbonate (PC). Combustion behaviors and thermal degradation properties of PC/PPPO system were assayed by limiting oxygen index (LOI), vertical burning test (UL‐94), cone calorimeter test, and thermogravimetric analysis. PC/6 wt % PPPO passed UL‐94 V‐0 rating with 3.0 mm samples and the LOI value was 34.1%, and PC/8 wt % PPPO also passed UL‐94 V‐0 rating with 1.6 mm samples and the LOI value was 36.3%. Scanning electron microscopy reveals that the char properties had crucial effects on the flame retardancy of PC. Mechanical properties and water resistance of PC/PPPO system were also measured. After water resistance test, PC/6 wt % PPPO with 3.0 mm samples and PC/8 wt % PPPO with 1.6 mm samples kept V‐0 rating and mass loss was only 0.2%. The results revealed that PPPO was an efficient flame retardant for PC. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synergistic effects of exfoliated LDH with some halogen‐free flame retardants in LDPE/EVA/HFMH/LDH nanocomposites

The synergistic effects of exfoliated layered double hydroxides (LDH) with some halogen‐free flame retardant (HFFR) additives, such as hyperfine magnesium hydroxide (HFMH), microencapsulated red phosphorus (MRP), and expandable graphite (EG), in the low‐density polyethylene/ethylene vinyl acetate copolymer/LDH (LDPE/EVA/LDH) nanocomposites have been studied by X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), thermal analysis (TGA and DTG), mechanical properties, limiting oxygen index (LOI), and UL‐94 tests. The XRD results show that EVA as an excellent compatilizer can promote the exfoliation of LDH and homogeneous dispersion of HFMH in the LDPE/EVA/HFMH/LDH nanocomposites prepared by melt‐intercalation method. The TEM images demonstrate that the exfoliated LDH layers can act as synergistic compatilizer and dispersant to make the HFMH particles dispersed homogeneously in the LDPE matrix. The results from the mechanical, LOI, and UL‐94 tests show that the exfoliated LDH layers can also act as the nano‐enhanced and flame retardant synergistic agents and thus increase the tensile strength, LOI values, and UL‐94 rating of the nanocomposites. The morphological structures of charred residues observed by SEM give the positive evidence that the compact charred layers formed from the LDPE/EVA/HFMH/LDH nanocomposites with the exfoliated LDH layers play an important role in the enhancement of flame retardant and mechanical properties. The TGA and DTG data show that the exfoliated LDH layers as excellent flame retardant synergist of MRP or EG can apparently increase the thermal degradation temperature and the charred residues after burning. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008