The Experts below are selected from a list of 234 Experts worldwide ranked by ideXlab platform
Zhengzhou Wang - One of the best experts on this subject based on the ideXlab platform.
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synergistic effect of nano magnesium amino tris methylenephosphonate and expandable graphite on improving Flame Retardant mechanical and thermal insulating properties of rigid polyurethane foam
Materials Chemistry and Physics, 2018Co-Authors: Lei Liu, Zhengzhou WangAbstract:Abstract A novel nano phosphorus and nitrogen Based Flame Retardant, i.e. magnesium amino-tris-(methylenephosphonate) (Mg-AMP) was synthesized and characterized by Fourier-transform infrared and X-ray diffraction spectroscopies, transmission electronic microscopy, and thermogravimetric analysis (TGA). Flame retarded rigid polyurethane (RPU) foams filled with nano Mg-AMP and expandable graphite (EG) were prepared, and a synergistic effect in Flame retardancy between Mg-AMP and EG in RPU foam was observed. The RPU foam containing 12 wt% EG and 3 wt% Mg-AMP (sample RPU/12EG/3Mg-AMP) reached a V0 rating in vertical UL-94 test with a limiting oxygen index of 29.5%. The peak heat release rate and total heat release of sample RPU/12EG/3Mg-AMP were obviously decreased by 52.4 and 42.9%, respectively compared with the foam with 15 wt% EG (sample RPU/15EG). Moreover, the compressive strength of sample RPU/12EG/3Mg-AMP was 35% higher than that of sample RPU/15EG, and the thermal conductivity of the former was lower than the one of the latter. TGA results indicated that the combination of Mg-AMP and EG clearly improved the thermal stability and yield of residual char of RPU foam.
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high performance nano zinc amino tris methylenephosphonate in rigid polyurethane foam with improved mechanical strength thermal stability and Flame retardancy
Polymer Degradation and Stability, 2018Co-Authors: Lei Liu, Zhengzhou WangAbstract:Abstract A novel phosphorus and nitrogen-Based Flame Retardant, zinc amino-tris-(methylenephosphonate) (Zn-AMP) was synthesized and characterized by X-ray diffraction and Fourier-transform infrared spectroscopies, transmission electronic microscopy, and thermogravimetric analysis (TGA). Zn-AMP was introduced into rigid polyurethane (RPU) foam with the aim of enhancing Flame Retardant, mechanical and thermal properties. The incorporation of 10 wt% Zn-AMP into RPU foam was found to increase the compressive strength by 67.9% as well as to reduce thermal conductivity compared with untreated foam. Foam containing 20 wt% Zn-AMP (sample RPU/20Zn-AMP) had a limiting oxygen index of 25.0% and a V0 rating in a vertical UL-94 test. Cone calorimeter data revealed that the peak heat release rate and total heat release of sample RPU/20Zn-AMP were decreased by 61.0 and 46.1%, respectively, compared with untreated foam. TGA results indicated that Zn-AMP clearly improved RPU foam's thermal stability.
Lei Liu - One of the best experts on this subject based on the ideXlab platform.
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synergistic effect of nano magnesium amino tris methylenephosphonate and expandable graphite on improving Flame Retardant mechanical and thermal insulating properties of rigid polyurethane foam
Materials Chemistry and Physics, 2018Co-Authors: Lei Liu, Zhengzhou WangAbstract:Abstract A novel nano phosphorus and nitrogen Based Flame Retardant, i.e. magnesium amino-tris-(methylenephosphonate) (Mg-AMP) was synthesized and characterized by Fourier-transform infrared and X-ray diffraction spectroscopies, transmission electronic microscopy, and thermogravimetric analysis (TGA). Flame retarded rigid polyurethane (RPU) foams filled with nano Mg-AMP and expandable graphite (EG) were prepared, and a synergistic effect in Flame retardancy between Mg-AMP and EG in RPU foam was observed. The RPU foam containing 12 wt% EG and 3 wt% Mg-AMP (sample RPU/12EG/3Mg-AMP) reached a V0 rating in vertical UL-94 test with a limiting oxygen index of 29.5%. The peak heat release rate and total heat release of sample RPU/12EG/3Mg-AMP were obviously decreased by 52.4 and 42.9%, respectively compared with the foam with 15 wt% EG (sample RPU/15EG). Moreover, the compressive strength of sample RPU/12EG/3Mg-AMP was 35% higher than that of sample RPU/15EG, and the thermal conductivity of the former was lower than the one of the latter. TGA results indicated that the combination of Mg-AMP and EG clearly improved the thermal stability and yield of residual char of RPU foam.
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high performance nano zinc amino tris methylenephosphonate in rigid polyurethane foam with improved mechanical strength thermal stability and Flame retardancy
Polymer Degradation and Stability, 2018Co-Authors: Lei Liu, Zhengzhou WangAbstract:Abstract A novel phosphorus and nitrogen-Based Flame Retardant, zinc amino-tris-(methylenephosphonate) (Zn-AMP) was synthesized and characterized by X-ray diffraction and Fourier-transform infrared spectroscopies, transmission electronic microscopy, and thermogravimetric analysis (TGA). Zn-AMP was introduced into rigid polyurethane (RPU) foam with the aim of enhancing Flame Retardant, mechanical and thermal properties. The incorporation of 10 wt% Zn-AMP into RPU foam was found to increase the compressive strength by 67.9% as well as to reduce thermal conductivity compared with untreated foam. Foam containing 20 wt% Zn-AMP (sample RPU/20Zn-AMP) had a limiting oxygen index of 25.0% and a V0 rating in a vertical UL-94 test. Cone calorimeter data revealed that the peak heat release rate and total heat release of sample RPU/20Zn-AMP were decreased by 61.0 and 46.1%, respectively, compared with untreated foam. TGA results indicated that Zn-AMP clearly improved RPU foam's thermal stability.
Sanna Lignell - One of the best experts on this subject based on the ideXlab platform.
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diverging temporal trends of human exposure to bisphenols and plastizisers such as phthalates caused by substitution of legacy edcs
Environmental Research, 2017Co-Authors: Irina Gyllenhammar, Anders Glynn, Bo Jonsson, Christian H Lindh, Per Ola Darnerud, Kettil Svensson, Sanna LignellAbstract:Phthalates and phenolic substances were investigated in urine samples from first-time mothers in Uppsala, Sweden, collected between 2009 and 2014. These substances have a comparably fast metabolism and urinary metabolites are predominantly analysed. The main aim was to investigate if measures to decrease production and use of certain phthalates and bisphenol A (BPA) have resulted in decreased human exposure, and to determine if exposures to replacement chemicals have increased. Temporal trends were evaluated for metabolites (n=13) of seven phthalates, a phthalate replacer, four different bisphenols, triclosan, one organophosphate-Based Flame Retardant, and for two pesticides. The results showed downward trends of several phthalates which are in the process of being regulated and phased out. Concomitantly, an increasing trend was seen for a metabolite of the phthalate replacer Di-iso-nonylcyclohexane 1,2-dicarboxylate (DiNCH). Bisphenol A (BPA) showed a downward trend, whereas bisphenol F, identified as one of the substitutes for BPA, showed an increasing trend. The decreasing trend of triclosan is likely due to declining use within the EU. Temporal trend studies of urine samples make it possible to investigate human exposure to rapidly metabolised substances and study how measures taken to regulate and replace problematic chemicals affect human exposure.
Per Blomqvist - One of the best experts on this subject based on the ideXlab platform.
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flammability smoke mechanical behaviours and morphology of Flame retarded natural fibre elium composite
Materials, 2019Co-Authors: Pooria Khalili, Brina Blinzler, Roland Kadar, Roeland Bisschop, Michael Forsth, Per BlomqvistAbstract:The work involves fabrication of natural fibre/Elium® composites using resin infusion technique. The jute fabrics were treated using phosphorus-carbon Based Flame Retardant (FR) agent, a phosphonate solution and graphene nano-platelet (GnP), followed by resin infusion, to produce FR and graphene-Based composites. The properties of these composites were compared with those of the Control (jute fabric/Elium®). As obtained from the cone calorimeter and Fourier transform infrared spectroscopy, the peak heat release rate reduced significantly after the FR and GnP treatments of fabrics whereas total smoke release and quantity of carbon monoxide increased with the incorporation of FR. The addition of GnP had almost no effect on carbon monoxide and carbon dioxide yield. Dynamic mechanical analysis demonstrated that coating jute fabrics with GnP particles led to an enhanced glass transition temperature by 14%. Scanning electron microscopy showed fibre pull-out locations in the tensile fracture surface of the laminates after incorporation of both fillers, which resulted in reduced tensile properties.
Yuan Hu - One of the best experts on this subject based on the ideXlab platform.
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Flame Retardant wrapped polyphosphazene nanotubes a novel strategy for enhancing the Flame retardancy and smoke toxicity suppression of epoxy resins
Journal of Hazardous Materials, 2017Co-Authors: Xin Wang, Bin Yu, Xiaming Feng, Xiaowei Mu, Richard K K Yuen, Yuan HuAbstract:Abstract The structure of polyphosphazene nanotubes (PZS) is similar to that of carbon nanotubes (CNTs) before modification. For applications of CNTs in polymer composites, surface wrapping is an economically attractive route to achieve functionalized nanotubes. Based on this idea, functionalized polyphosphazene nanotubes (FR@PZS) wrapped with a cross-linked DOPO-Based Flame Retardant (FR) were synthesized via one-step strategy and well characterized. Then, the obtained FR@PZS was introduced into epoxy resin (EP) to investigate Flame retardancy and smoke toxicity suppression performance. Thermogravimetric analysis indicated that FR@PZS significantly enhanced the thermal stability of EP composites. Cone calorimeter results revealed that incorporation of FR@PZS obviously improved Flame Retardant performance of EP, for example, 46.0% decrease in peak heat release rate and 27.1% reduction in total heat release were observed in the case of epoxy composite with 3 wt% FR@PZS. The evolution of toxic CO and other volatile products from the EP decomposition was significantly suppressed after the introduction of FR@PZS, Therefore, the smoke toxicity associates with burning EP was reduced. The presence of both PZS and a DOPO-Based Flame Retardant was probably responsible for this substantial diminishment of fire hazard.
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combustion properties and thermal degradation behavior of polylactide with an effective intumescent Flame Retardant
Polymer Degradation and Stability, 2009Co-Authors: Jing Zhan, Lei Song, Shibin Nie, Yuan HuAbstract:Abstract An intumescent Flame Retardant spirocyclic pentaerythritol bisphosphorate disphosphoryl melamine (SPDPM) has been synthesized and its structure was characterized by Fourier transformed infrared spectrometry (FTIR), 1 H and 31 P nuclear magnetic resonances (NMR). A series of polylactide (PLA)-Based Flame Retardant composites containing SPDPM were prepared by melt blending method. The combustion properties of PLA/SPDPM composites were evaluated through UL-94, limiting oxygen index (LOI) tests and microscale combustion calorimetry (MCC) experiments. It is found that SPDPM integrating acid, char and gas sources significantly improved the Flame retardancy and anti-dripping performance of PLA. When 25 wt% Flame Retardant was added, the composites achieved UL-94 V0, and the LOI value was increased to 38. Thermogravimetric analysis (TGA) showed that the weight loss rate of PLA was decreased by introduction of SPDPM. In addition, the thermal degradation process and possible Flame Retardant mechanism of PLA composites with SPDPM were analyzed by in situ FTIR.