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The β-FeOOH nanorod-filled coatings were deposited onto flexible polyurethane foam by layer-by-layer assembly technique to reduce its flammability. The coatings were constructed by two assembly systems: one was bilayer system, which was comprised of polyethylenimine and β-FeOOH nanorods; other one was trilayer system, which was comprised of polyethylenimine, β-FeOOH nanorods, and sodium alginate. Scanning electron microscopy images indicated that the randomly oriented and entangled network structure can only be observed for the coating that assembled by trilayer system. Cone calorimetry test revealed that the coating assembled by trilayer system can lead to significant reduction in peak heat release rate compared with those of control foam, 61.8% peak heat release rate reduction ever occurred to the eight trilayers coated sample, but the coating assembled by bilayer system has slight reduction (

The main aim of this work was to investigate the synergistic effect of expandable graphite (EG) and aluminum hypophosphite (AHP) on the flame retardancy of rigid polyurethane foams (RPUFs). A series of flame retardant RPUF containing EG and AHP were prepared by one-shot and free-rise method. The flame retardant, thermal degradation, and combustion properties of RPUF hybrids were characterized through limiting oxygen index (LOI) test, vertical burning (UL-94) test, thermogravimetric analysis and microscale combustion calorimeter. The LOI and UL-94 results showed that the RPUF sample with 10 wt% EG and 5 wt% AHP passed UL-94 V-0 rating and reached a relatively high LOI value of 28.5%, which is superior over other EG/AHP ratios in RPUF at the equivalent filler loading. Microscale combustion calorimeter results revealed that the incorporation of EG and AHP into RPUF reduced the peak heat release rate and total heat release, thus decrease the fire risk of RPUF significantly. Incorporation of EG and AHP improved the thermal stability of RPUF as observed from the thermogravimetric analysis results and also enhanced the thermal resistance of char layer at high temperature from scanning electron microscopy and Raman spectroscopy. Moreover, it could be seen from thermogravimetric analysis/infrared spectrometry spectra that the addition of EG and AHP significantly decreased the combustible gaseous products such as hydrocarbons and ethers. Finally, the synergistic mechanism in flame retardancy was discussed and speculated. Copyright © 2014 John Wiley & Sons, Ltd.

A new phosphorous- and nitrogen-containing reactive monomer, DMPMA, was first synthesized by nucleophilic substitution reaction of 2-(6-oxido-6H-dibenz[c,e][1,2]oxaphos-phorin-6-yl) methanol, N-hydroxymethyl acrylamide and methyldichlorophosphate. The copolymer of styrene (St) and DMPMA (poly(St-co-DMPMA)) was prepared and then characterized by Fourier transform infrared, differential scanning calorimetry, thermogravimetric analysis (TGA), microscale combustion calorimeter and steady-state tube furnace (SSTF). The results proved that poly(St-co-DMPMA) was well synthesized, while the glass transition temperature of the copolymer was decreased with increasing DMPMA content. The TGA results showed that the initial degradation temperature of poly(St-co-DMPMA) decreased, but its char yield and decomposition temperature improved compared to that of pure polystyrene. After incorporating DMPMA, the fire performance of the copolymer was significantly improved. The results obtained from the SSTF indicated that the carbon monoxide and smoke yield density were increased due to the incomplete combustion of the copolymer. © 2014 John Wiley & Sons, Ltd.

A reactive extrusion process was developed to fabricate polymer/graphene nanocomposites with good dispersion of graphene sheets in the polymer matrix. The functionalized graphene nanosheet (f-GNS) activated by diphenylmethane diisocyanate was incorporated in thermoplastic polyester elastomer (TPEE) by reactive extrusion process to produce the TPEE/f-GNS masterbatch. And then, the TPEE/f-GNS nanocomposites in different ratios were prepared by masterbatch-based melt blending. The structure and morphology of functionalized graphene were characterized by Fourier transform infrared, X-ray photoelectron spectroscopy, X-ray diffraction and transmission electron microscopy (TEM). The incorporation of f-GNS significantly improved the mechanical, thermal and crystallization properties of TPEE. With the incorporation of only 0.1 wt% f-GNS, the tensile strength and elongation at break of nanocomposites were increased by 47.6% and 30.8%, respectively, compared with those of pristine TPEE. Moreover, the degradation temperature for 10 wt% mass loss, storage modulus at −70°C and crystallization peak temperature (Tcp) of TPEE nanocomposites were consistently improved by 17°C, 7.5% and 36°C. The remarkable reinforcements in mechanical and thermal properties were attributed to the homogeneous dispersion and strong interfacial adhesion of f-GNS in the TPEE matrix. The functionalization of graphene was beneficial to the improvement of mechanical properties because of the relatively well dispersion of graphene sheets in TPEE matrix, as suggested in the TEM images. This simple and effective approach consisting of chemical functionalization of graphene, reactive extrusion and masterbatch-based melt blending process is believed to offer possibilities for broadening the graphene applications in the field of polymer processing. Copyright © 2014 John Wiley & Sons, Ltd.

A phosphorus and silicon containing liquid monomer (9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide–vinyltrimethoxysilane (DOPO–VTS)) was synthesized by the reaction between DOPO and VTS. DOPO–VTS and methacryloxypropyltrimethoxylsilane were introduced into unsaturated polyester resin to prepare flame retardant UPR/SiO2 (FR-UPR/SiO2) hybrid materials by sol–gel method and curing process. DOPO–VTS contributes excellent flame retardancy to UPR matrix, which was confirmed by the limiting oxygen index and microscale combustion calorimeter results. The thermogravimetric analysis (TGA) results indicate that the FR-UPR/SiO2 hybrid materials possess higher thermal stability and residual char yields than those of pure UPR at high temperature region. The thermal degradation of materials was investigated by TGA/infrared spectrometry (TG-IR) and real-time infrared spectrometry (RT-IR), providing insight into the thermal degradation mechanism. Moreover, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were used to explore the morphologies and chemical components of the residual char. Copyright © 2013 John Wiley & Sons, Ltd.

A new series of microcapsules containing pentaerythritol (PER) and ammonium polyphosphate (APP) with glycidyl methacrylate and butyl methacrylate as shell materials were synthesized by in situ polymerization. The structure and performance of the microencapsulated APP and microencapsulated PER were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and water contact angle. The flame retarded ethylene-vinyl acetate copolymer (EVA) composites were studied by limiting oxygen index, UL-94 test, and cone calorimeter. It was found that the microencapsulation of flame retardants (FRs) with the glycidyl methacrylate and butyl methacrylate lead to a decrease in the particle's water solubility and an improvement of the hydrophobicity. Results also demonstrated that the FR properties of EVA/microencapsulated APP/microencapsulated PER composites were better than those of the EVA/APP/PER composites at the same loading of FRs. The thermogravimetric analysis results reflected that the microencapsulated EVA composites had better thermal stability because of the forming of stable char during the combustion. Copyright © 2013 John Wiley & Sons, Ltd.

In this work, we reported the synthesis, characterization of Ce-doped titania nanotubes (Ce-TNTs), and application in flame retardancy of an intumescent flame-retardant polystyrene (PS/IFR) system. The flame retardancy of polystyrene (PS) composite that was composed of pentaerythritol, microencapsulated ammonium polyphosphate, and PS was enhanced significantly by adding a small amount (0.1 wt%) of (Ce-TNTs). The thermal properties of the flame-retardant PS were investigated by thermogravimetric analysis, limiting oxygen index (LOI), vertical burning test (UL-94), scanning electronic microscopy, dynamic mechanical thermal analysis, and the real-time Fourier transform infrared spectrometry (FTIR). The maximal decomposition rate temperature of PS/IFR containing Ce-TNTs in air is much higher than that of other PS composite without Ce-TNTs. The LOI value of PS/IFR that contained 0.1 wt% of Ce-TNTs was increased from 27.0 to 28.5, and the UL-94 rating was also enhanced to V-0 from no rating when the total loading of additive was the same. The real-time FTIR showed that the degradation process was changed after the addition of TNTs. All results indicated that Ce-TNTs had a significant synergistic effect on the flame retardancy of PS/IFR. Copyright © 2012 John Wiley & Sons, Ltd.

2,2-Bis[4-(4-amino-2-trifluoromehyloxyphenyl) phenyl]propane (BAFPP) was synthesized based on 2-chlorobenzotrifluoride and bisphenol A and characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance. BAFPP was used as a chain extender to prepare a series of fluorine-containing polyurethane elastomers (FPUEs) with different fluorine contents by changing the soft segments and isocyanate index (R). The FPUEs were investigated by water absorption, contact angle, X-ray photoelectron spectroscopy, thermogravimetric analysis, and microscale combustion calorimetry. The results show that the FPUEs prepared from BAFPP were elastomers that have low surface tension, low water absorption, and good thermal stability. Furthermore, FPUEs also exhibit good flame resistance, and the peak heat release rate of FPUE based on BAFPP (282.9 W/g) is much lower than that of polyurethane elastomer without the F element (537.2 W/g). Copyright © 2011 John Wiley & Sons, Ltd.

Polymer/α-titanium phosphate (nano)composites are reported for the first time in this paper. The α-titanium phosphate was synthesized via the hydrothermal method and organically modified by ethylamine intercalation. Flame retardant polypropylene/α-titanium phosphate (nano)composites were prepared by melt blending. The titanium phosphates and (nano)composites were characterized and enhanced thermal stability, flame retardancy, and mechanical properties were obtained. Thermogravimetric analysis results showed an increase of 65°C in the maximum decomposition temperature and a 34% reduction in the peak value of derivative weight curve, demonstrating enhanced thermal stability. Improved mechanical properties, including elongation at break (70%), impact strength (29%), Young's modulus (11%), and hardness (35%), were obtained. Materials flame retardancy was also improved according to limiting oxygen index and vertical burning test. Probable mechanism for (nano)composites properties enhancements are discussed. Copyright © 2011 John Wiley & Sons, Ltd.

An intumescent flame retardant system composed of ammonium polyphosphate (APP) and pentaerythritol (PER) was used for flame retarding ethylene–propylene–diene-modified elastomer (EPDM)/polypropylene (PP) blends. Cerium phosphate (CeP) was synthesized and the effect on flame retardancy and thermal stability of EPDM/PP composites based on intumescent flame retardant (IFR) were studied by limiting oxygen index (LOI), UL-94, and thermogravimetic analysis (TGA), respectively. Scanning electron microscopy (SEM) and Fourier transform infrared spectrometry (FTIR) were used to analyze the morphological structure and the component of the residue chars formed from the EPDM/PP composites, and the mechanical properties of the materials were also studied. The addition of CeP to the EPDM/PP/APP/PER composites gives better flame retardancy than that of EPDM/PP/APP/PER composites. TGA and RT-FTIR studies indicated that an interaction occurs among APP, PER, and EPDM/PP. The incorporation of CeP improved the mechanical properties of the materials. Copyright © 2010 John Wiley & Sons, Ltd.

A triazine ring-containing charring agent (PEPATA) was synthesized via the reaction between 2,6,7-trioxa-l-phosphabicyclo-[2.2.2]octane-4-methanol (PEPA) and cyanuric chloride. It was applied into intumescent flame retardant epoxy resins (IFR-EP) as a charring agent. The effect of PEPATA on fire retardancy and thermal degradation behavior of IFR-EP system was investigated by limited oxygen index (LOI), UL-94 test, microscale combustion calorimetry (MCC), thermogravimetric analysis (TGA) and thermogravimetric analysis/infrared spectrometry (TG-IR). The glass transition temperatures (Tg) of IFR-EP systems were studied by dynamic mechanical analysis (DMA). The LOI values increased from 21.5 for neat epoxy resins (EPs) to 34.0 for IFR-EP, demonstrating improved flame retardancy. The TGA curves showed that the amount of residue of IFR-EP system was largely increased compared to that of neat EP at 700 °C. The new IFR-EP system could apparently reduce the amount of decomposing products at higher temperatures and promotes the formation of carbonaceous charred layers that slowed down the degradation. Copyright © 2010 John Wiley & Sons, Ltd.

In this paper, the effect of organo-modified montmorillonite (OMMT) on a novel intumescent flame retardant (IFR) system was studied in poly(1,4-butylene terephthalate) (PBT) composites containing microencapsulated ammonium polyphosphate (MAPP) and melamine cyanurate (MC). Nanocomposite morphology was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Thermal decomposition analysis was studied via thermogravimetric analysis (TGA). Combustion behavior was investigated by microcombustion calorimeter (MCC), limited oxygen index (LOI), and UL-94 test. Residues obtained after samples treated in muffle furnace at 500°C under air condition for 10 min were analyzed through X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). It was found that the addition of OMMT improved the flame retardancy of PBT/IFR composites significantly. A mass of microcomposite structure particles formed in the heating or combustion process of PBT/IFR/OMMT nanocomposites were found for the first time in the SEM images, which is strong evidence to confirm the migration or accumulation of montmorillonite and carbonaceous-silicate materials during the heating or combustion process. Copyright © 2010 John Wiley & Sons, Ltd.

The flame retardancy mechanisms of poly(1,4-butylene terephthalate) (PBT) containing microencapsulated ammonium polyphosphate (MAPP) and melamine cyanurate (MC) were investigated via pyrolysis analysis (thermogravimetric analysis (TGA), real-time Fourier transform infrared (FTIR), TG-IR), cone calorimeter test, combustion tests (limited oxygen index (LOI), UL-94), and residue analysis (scanning electron microscopy (SEM)). A loading of 20 wt% MC to PBT gave the PBT composites an LOI of 26%, V-2 classification in UL-94 test and a high peak heat release rate (HRR) in cone calorimeter test. Adding APP to PBT/MC composites did not improve their flame retardancy. In comparison with the addition of ammonium polyphosphate (APP) to PBT, MAPP with silica gel shell and MAPP with polyurethane shell both promoted the intumescent char-forming and improved the flame retardancy of PBT through different mechanisms in the presence of MC. These two halogen-free PBT composites with V-0 classification according to UL-94 test were obtained; their LOI were 32 and 33%, respectively. Copyright © 2010 John Wiley & Sons, Ltd.

A novel intumescent gel-silica/ammonium polyphosphate core-shell flame retardant (MCAPP), which contains silicon, phosphorus, and nitrogen, has been prepared by in situ polymerization. The structure of MCAPP was characterized by Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The properties of MCAPP were investigated by water solubility, hydrophilicity, and morphological determination. The flame retardancy and thermal stability of polyurethane (PU) composite with MCAPP were evaluated by limiting oxygen index (LOI), UL-94 test, cone calorimetry, and thermogravimetric analysis (TGA). The results showed that MCAPP could decrease the heat release rate (HRR) and increase the thermal stability of PU materials greatly. Finally, water-resistant properties of PU/FR composites were also studied. Copyright © 2010 John Wiley & Sons, Ltd.

A novel phosphorus monomer (PDHA) has been synthesized through phenyl dichlorophosphate (PDPC) reacting with 2-hydroxyethyl acrylate (HEA). The structure of PDHA was characterized by Fourier transform infrared spectroscopy (FTIR) and 1H nuclear magnetic resonance spectroscopy (1H NMR). A series of UV curable resins were manufactured by blending PDHA with triglycidyl isocyanurate acrylate (TGICA) at different weight ratios. The fire performance was examined by micro-scale combustion calorimeter (MCC) and limiting oxygen index (LOI). The results obtained from MCC indicated that the addition of PDHA to TGICA reduced the HRR and HRC. In addition, the LOI values varied from 28 to 34. The char residues of the composites were observed by scanning electron microscopy (SEM). Their thermal degradation behavior was investigated by thermogravimetric analysis and real time FTIR analysis (RT-FTIR). The test results indicated that when the weight ratio of PDHA/TGICA = 1:1, the onset temperature of the composite was highest and the most char residue at 700°C was observed. RT-FTIR showed that the phosphate group of PDHA first degraded to form poly(phosphoric acid)s at around 300°C, which had the major contribution to form the compact char to protect the sample from further degradation. Copyright © 2010 John Wiley & Sons, Ltd.

The bisphenol A epoxy acrylate resin (EA) containing a small amount of layered double hydroxide (LDH) was cured within seconds under UV irradiation at ambient temperature. Its microstructure was characterized by X-ray diffraction (XRD). The combustion behavior of the coating was examined by the Microscale Combustion Calorimeter (MCC) and limiting oxygen index (LOI). The results obtained from MCC and LOI indicated that the addition of LDH into EA could decrease the peak of heat release rate (HRR) for the films and increase the LOI value of the films. Thermal behavior of the cured films was studied by thermogravimetric analysis (TGA). The results for TGA indicated that with increase in the contents of LDH, the residual char of UV-cured films increased at 600 °C. The evolved products for UV-cured films were characterized using thermogravimetric analysis/infrared spectrometry (TGA-IR). It was implied that the mechanism of thermal degradation for EA0 was different from EA4. Viscoelastic property of photo-cured hybrid materials was evaluated by dynamic-mechanical analysis. The effect of LDH on the properties of UV-curable films was critically evaluated in this paper. Copyright © 2010 John Wiley & Sons, Ltd.

Microencapsulated ammonium polyphosphate (APP) with polyurethane (MCAPP) was prepared by in situ polymerization of pentaerythtritol (PER) and toluene-2,4-diisocyanate (TDI) in the presence of added APP. MCAPP was then incorporated into polyurethane (PU) to obtain flame retarded PU/MCAPP. Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) showed that APP was encapsulated by a layer of PU. It found that the optimal reaction time was 8 hr and microencapsulation led to an improvement in water leaching from scanning electron microscopy (SEM) and determination of water resistance. Thermal degradation of flame retarded PU was also investigated by thermogravimetric analysis (TGA). UL-94 test and SEM were performed before and after water treatment at 75°C for seven days, and the results showed that PU loading of 30% MCAPP can maintain the V-0 level, due to the shield effect of microencapsulation. Copyright © 2008 John Wiley & Sons, Ltd.

Effect of metallic oxides on flame retardancy and the thermal stability of styrene butadiene rubber (SBR) composites based on ammonium polyphosphate (APP) and pentaerythritol (PER) was studied by the limiting oxygen index (LOI), UL 94, the cone calorimeter tests, and thermogravimetry analysis (TGA), respectively. Scanning electron microscopy (SEM) and wide-angle X-ray diffraction (WAXD) were used to analyze the morphological structure and the component of the residue chars formed from the SBR composites accordingly. The addition of zirconium dioxide (ZrO2) at a loading of 3.4 phr could improve the UL 94 test rating of the composite to V-0. The TGA data illustrated that the metallic oxides could enhance the thermal stability of the SBR/Intumescent flame retardant additives (IFRs) composites at high temperature and increase the residue. Cone calorimeter test gave much clear evidence that the incorporation of ZrO2 into SBR/IFRs composites resulted in the significant deduction of the heat release rate (HRR) values, and the SEM images showed that the char layers of the composites containing the metallic oxides became more compact. From the WAXD pattern, zirconium phosphate (ZrP2O7) may be formed by the reaction between ZrO2 and APP. Due to the addition of ZrO2 and the formation of ZrP2O7, the flame retardancy of the composite was improved. Copyright © 2009 John Wiley & Sons, Ltd.

Ferric pyrophosphate (FePP) was added to an ammonium polyphosphate (APP)—pentaerythritol (petol) intumescent flame retardant (IFR) system in polypropylene (PP) matrix, with subsequent investigation into the synergistic effect between FePP and the IFRs. Limited oxygen index (LOI), UL-94 test and cone calorimeter test were employed to study the flame retardance of the synthesized flame retardant PP composites. Thermogravimetric analysis (TGA) and thermogravimetric analysis-infrared spectrometry (TG-IR) were used to study their thermal degradation characteristics and gas products. TG-IR results demonstrate that there is no Fe (CO)5 produced from PP/IFR/FePP system, which implies that the flame retardant mechanism of PP/IFR/FePP system is in the condensed phase rather than in the gas phase. Real time FTIR and X-ray photoelectron spectroscopy (XPS) were used to monitor the thermal oxidative stability and the high temperature performance of the flame retardant PP composites. The real time FTIR spectra show that all peaks around 2900 cm−1 almost disappear at 380°C for the PP/IFR system, meaning that PP decomposes completely at this temperature. But after the addition of 2 wt%wt% FePP, the peaks still exist till 400°C. XPS shows that the aliphatic carbon atom content in PP/23 wt%wt% IFR/2 wt%wt% FePP (63.8%) is much higher than the one without FePP, and the total oxygen atom content in PP/23 wt%wt% IFR/2 wt%wt% FePP is just 19.1%, while the one in PP/25 wt% IFR is as high as 35.7%. Copyright © 2009 John Wiley & Sons, Ltd.

A series of polyurethane (PU) microencapsulated ammonium polyphosphate (MCAPP) were prepared by in situ polymerization from toluene-2,4-diisocyanate (TDI), polyethylene glycol (PEG), and pentaerythtritol (PER). And the structure was characterized by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Then it chose the optimal PEG constituent to design microcapsule from scanning electron microscopy (SEM) and water solubility test. The combustion and thermal degradation behaviors of PU blended APP or MCAPP were investigated by thermogravimetric analysis (TGA), UL-94 test, and microcombustion calorimetry. The results showed that the PU/MCAPP had better thermal stability and flame retardance, due to the stable char forming by APP and PU shell. Moreover, the water resistance of flame retarded PU composite was greatly improved. Copyright © 2009 John Wiley & Sons, Ltd.

In the present study, polypropylene/aluminium trihydroxide/Fe-montmorillonite (PP/ATH/Fe-MMT) nanocomposites were prepared by melt-intercalation method. This was been designed to determine whether the presence of structural iron in the matrix could enhance the thermal stability and flammability of nanocomposites. In order to prove the effect of Fe3+ in the structural silicate layers, samples of PP/ATH and PP/ATH/Na-MMT (no Fe3+ in structural silicate layers) were prepared under the same conditions. Fe-MMT and Na-MMT were modified by cetyltrimethyl ammonium bromide (CTAB). The nanocomposite structures were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) was applied to test the thermal properties of nanocomposites. In addition, the limiting oxygen index (LOI) of PP/ATH/Fe-MMT nanocomposites was increased, and no dripping phenomenon was found through the UL-94 vertical burning test. Copyright © 2009 John Wiley & Sons, Ltd.

With a shell of PVA–melamine–formaldehyde resin, microencapsulated ammonium polyphosphate (VMFAPP) is prepared by in situ polymerization and characterized by FTIR and XPS. Microencapsulation gives VMFAPP better water resistance and flame retardance compared with APP in PP. Thermal stability and fire resistance behavior have been analyzed and compared. The LOI value of the PP/VMFAPP composite is higher than that of the PP/APP composite. The UL 94 ratings of most of the PP/VMFAPP composites are V-0, whereas PP/APP gives no rating at the 30% additive level. The water resistant properties of the PP composites are studied. Results of the cone calorimeter experiment show that VMFAPP is an effective flame retardant in PP compared with APP. The thermal degradation behaviors of APP and VMFAPP have been studied using TG and dynamic FTIR. Copyright © 2008 John Wiley & Sons, Ltd.

The performances of the novel intumescent flame retardant (IFR) polypropylene (PP) composites containing melamine phosphate (MP) and tris(1-oxo-2,6,7-trioxa-1-phosphabicyclo[2,2,2]methylene-4)phosphate (TPMP) were investigated. The flame retardancy of IFR-PP system was characterized by limiting oxygen index (LOI) and UL 94 and cone calorimeter. The morphology of the char obtained after cone calorimeter testing was studied by scanning electron microscopy (SEM). The thermal oxidative degradation (TOD) of the composites was investigated by using thermogravimetric analysis (TGA) and real-time Fourier transform infrared spectroscopy (RT-FTIR). Compared with the PP/ TPMP or PP/ MP binary composite, at the same addition level, the LOI values of the PP/MP/TPMP ternary composites increase and reach V-0 at the suitable MP/TPMP ratio. The results of TGA and RT-FTIR showed the existence of the interaction between IFR and PP. Copyright © 2008 John Wiley & Sons, Ltd.

The synergistic effect between a char forming agent (CFA) and microencapsulated ammonium polyphosphate (MAPP) on the thermal and flame retardancy of polypropylene (PP) are investigated by limiting oxygen index (LOI), UL-94 test, cone calorimetry, thermogravimetric analysis (TGA), scanning electron micrograph (SEM), and water resistance test. The results of cone calorimetry show that heat release rate peak (PHRR), total heat release (THR), and the mass loss of PP with 30 wt% intumescent flame retardant (IFR, CFA/MAPP = 1:2) decreases remarkably compared with that of pure PP. The HRR, THR, and mass loss decrease, respectively from 1140 to 100 kW/m2, from 96 to 16.8 MJ/m2, and from 100 to 40%. The PP composite with CFA/MAPP = 1:2 has the best water resistance, and it can still obtain a UL-94 V-0 rating after 168 hr soaking in water. Copyright © 2008 John Wiley & Sons, Ltd.

In this work, Fe-montmorillonite (Fe-MMT) is synthesized and used as a synergistic agent in ethylene vinyl acetate/magnesium hydroxide (EVA/MH) flame retardant formulations. The synergistic effect of Fe-MMT with magnesium hydroxide (MH) as the halogen-free flame retardant for ethylene vinyl acetate (EVA) is studied by thermogravimetric analysis (TGA), limiting the oxygen index (LOI), UL-94, and cone calorimetry test. Compared with that of Na-MMT, it indicates that the synergistic effects of Fe-MMT enhance the LOI value of EVA/MH polymer and improve the thermal stability and reduce the heat release rate (HRR). The structure and morphology of nanocomposites are studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The mechanical properties of the EVA composites have also been studied here, indicating that the use of Fe-MMT reduces the amount of inorganic fillers. MH hence enhances the mechanical properties of the EVA composite while keeping the UL-94 V-0 rating. Copyright © 2008 John Wiley & Sons, Ltd.

Nanoporous nickel phosphate VSB-1 was synthesized by hydrothermal method and its structure was characterized. Then VSB-1 was added to the ammonium polyphosphate (APP) and pentaerythritol (petol) system in a polypropylene (PP) matrix for the first time, and the synergistic effect of VSB-1 with intumescent flame retardants (IFR) was studied. With the addition of 2 wt% VSB-1 and 23 wt% IFR, the LOI value of PP/IFR composites increased from 28.0 to 35.5. The UL-94 test showed that PP with 20% IFR burned and had no rating, but with the addition of 2 wt% of VSB-1 and 18% of IFR, it could reach V-0 rating. The results of the X-ray photoelectron spectroscopy (XPS) showed that the ratios of P/C and N/C of PP/IFR/VSB-1 systems changed significantly from 0.133 to 0.205 (54% increase) and from 0.0328 to 0.047 (45.4% increase), respectively under 800°C for 10 min. Compared with the organophilic montmorillonite (OMT), 4 A zeolite, and zinc tetraborate (ZB), VSB-1 showed better synergistic effect at the same loading. Copyright © 2008 John Wiley & Sons, Ltd.

A series of UV-curable intumescent flame retardant resins was obtained by blending phosphate triacrylate (TAEP) in certain ratios with star poly(urethane acrylate) (SPUA) oligomer. The flammability of the cured films was characterized by limited oxygen index (LOI), UL 94, and the cone calorimeter. The results showed that the cured TAEP/SPUA samples greatly expanded while burning. A distinct synergistic effect was found between TAEP and SPUA. TAEP2 sample showed the highest LOI value (41) among all resins. The cone calorimeter results showed that the peak heat release rates and carbon monoxide yield decreased to the approximate level. The degradation was monitored by thermogravimetric analysis and real-time Fourier transform infrared spectroscopy. A degradation mechanism is suggested in which the phosphate group in TAEP first degraded to form poly(phosphoric acid)s, which further catalyzed the degradation of the material to form char with emission of carbon dioxide and nitrogen volatiles from SPUA, leading to the formation of expanding char. The morphologic structures of crusts of the formed chars were observed by scanning electron microscopy, demonstrating the synergistic effect between TAEP and SPUA. Copyright © 2008 John Wiley & Sons, Ltd.

A novel star polyurethane acrylate (SPUA) used for UV-curable coating was prepared from 2,4-toluene diisocyanate, 2-hydroxyethyl arcylate, and hexakis(2-hydroxyethyl)melamine, and characterized using FTIR, 1H-NMR, and elemental analysis. Its UV curing behaviors investigated via FTIR clearly indicated that this monomer could be cured rapidly at air atmosphere. The conversion of the unsaturated bond of the cured monomer sample is near to 72% after exposed under UV light for 40 sec. The hardness, flexibility, and mechanical properties of the cured film were also investigated. The thermal stability of the cured film was studied using thermogravimetric analysis (TGA) and real time Fourier transform infrared (RTFTIR). Results showed that this oligomer has some superior properties and can be used for UV curing coating. Copyright © 2007 John Wiley & Sons, Ltd.

In this article, silicone rubber (SR)/clay nanocomposites were synthesized by a melt-intercalation process using synthetic Fe-montmorillonite (Fe-MMT) and natural Na-MMT which were modified by cetyltrimethyl ammonium bromide (CTAB). This study has been designed to determine if the presence of structural iron in the matrix can result in radical trapping and then enhance thermal stability, affect the crosslinking degree and elongation. The SR/clay nanocomposites were characterized by X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM). Exfoliated and intercalated nanocomposites were obtained. Thermo gravimetric analysis (TGA) and mechanical performance were applied to test the properties of the SR/clay nanocomposites. The presence of iron significantly increased the onset temperature of thermal degradation in SR/Fe-MMT nanocomposites. The thermal stability, gel fraction and mechanical property of SR/Fe-MMT were different from the SR/Na-MMT nanocomposites. So the iron not only in thermal degradation but in the vulcanization process acted as an antioxidant and radicals trap. Copyright © 2006 John Wiley & Sons, Ltd.

Poly(propylene)/clay nanocomposites were prepared by a “one step” method, using pristine montmorillonite (MMT) with surfactant loading at different ratios. The nanocomposite structure was examined using X-ray diffraction (XRD), transmission electron microscopy (TEM) and high resolution electron microscopy (HREM). This study showed that the presence of maleic anhydride modified poly(propylene) (MAPP) and the ratio of surfactant to MMT both influenced the dispersion of MMT in the hybrids. The thermal stability and flame retardant property were investigated; the synergistic effect between MMT and an intumescent flame retardant and the flame retardant mechanism are discussed in this paper. Copyright © 2006 John Wiley & Sons, Ltd.

This study investigates the influence of nylon-6 (PA-6) and ethylene-vinyl acetate copolymer (EVA) alloy/clay nanocomposites on the properties of the flame-retardant (FR) poly(propylene). Cone calorimetry and scanning electron microscopy (SEM) techniques were used to investigate the effect of PA-6 and EVA alloy nanocomposites on the fire properties and dispersion of intumescent flame-retardants (IFRs). The experimental results show that PA-6 and EVA alloy nanocomposites improve the fire and mechanical properties of the FR poly(propylene). It is also shown that the improvement of the properties mainly depends on the weight ratio of PA-6 and EVA in the alloys. The probable mechanisms are discussed in this paper. Copyright © 2005 John Wiley & Sons, Ltd.