Aluminium Trihydroxide - Explore the Science & Experts | ideXlab

Scan Science and Technology

Contact Leading Edge Experts & Companies

Aluminium Trihydroxide

The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform

Serge Bourbigot – One of the best experts on this subject based on the ideXlab platform.

  • Smoke composition using MLC/FTIR/ELPI: Application to flame retarded ethylene vinyl acetate
    Polymer Degradation and Stability, 2015
    Co-Authors: Franck-estime Ngohang, Gaelle Fontaine, Serge Bourbigot

    Abstract:

    Abstract This paper is devoted to the interpretation of smoke data in terms of the fire behaviour of ethylene vinyl acetate unfilled and filled with Aluminium Trihydroxide (EVA and EVA/ATH), under different fire scenarios: 25, 35, 50 and 75 kW/m 2 . Flammability parameters, evolved gases and soot particles were evaluated for both materials (EVA and EVA/ATH) as a function of applied heat flux, using a combined Mass Loss Cone, Fourier Transform Infrared spectroscopy and Electrical Low Pressure Impactor (MLC/FTIR/ELPI) in a simultaneous analysis bench test. It was found that the EVA formulation leads to the formation of a carbonaceous layer (char) at low heat flux (25 kW/m 2 ), which blocks the release of decomposition gases, including flammable gases, thereby delaying the onset of piloted ignition of EVA relative to EVA/ATH. Total Heat Release (THR) measurements during tests performed on EVA show that this value remains constant at all heat fluxes, which is consistent with the fact that no residue of the EVA samples remains at the end of the fire tests. In the case of EVA/ATH however, the measured THR is proportional to the external heat flux because the quantity of combusted material increases as a function of the thermal stress applied. Calculation of the average effective heat of combustion (AEHC) of the EVA and EVA/ATH material yielded similar values, in both cases, under all four fire scenarios. With respect to gas phase analysis, the concentration of acetic acid (CH 3 COOH) release in the smoke of EVA (from the de-acetylation of vinyl acetate) was found to increase as the heat flux decreases, with a significant difference at 25 kW/m 2 relative to 35, 50 and 75 kW/m 2 . Concerning EVA/ATH, it appears that there is a transformation of CH 3 COOH to acetone (CH 3 COCH 3 ) attributed to the catalytic effect of Al 2 O 3 , which increases as the heat flux increases. Calculation of gas species yields revealed that the CO yields of EVA/ATH are higher than those of neat EVA, which can be ascribed to the incomplete combustion reaction of the flame retarded material (EAV/ATH) as compared to neat EVA; an exception was nevertheless noted at 25 kW/m 2 , where carbonization of EVA was also reported. In relation to ex situ analysis of particle size distribution and concentration in the EVA and EVA/ATH smoke, it was shown that ultrafine and fine particles are present in much higher concentration than particles above 1 μm (≥1 μm) for both formulations at all applied heat fluxes. Nonetheless, the more ultrafine particles (those of 6 nm) were solely detected in the EVA/ATH smoke, suggesting that the ATH flame retardant additive may promote the release of these ultrafine particles.

  • the fire retardant mechanism of ethylene vinyl acetate elastomer evm containing Aluminium Trihydroxide and melamine phosphate
    RSC Advances, 2014
    Co-Authors: Carmen Hoffendahl, Gaelle Fontaine, Sophie Duquesne, Frank Taschner, Martin Mezger, Serge Bourbigot

    Abstract:

    The fire retardancy and smoke release of ethylene vinyl acetate (vinyl acetate content of 60%, EVM) with Aluminium Trihydroxide (ATH) and melamine phosphate (MP) are evaluated by cone calorimetry, the limiting oxygen index (LOI), UL-94 and a home-made smoke test. It was found that EVM–ATH has better fire retardant properties and a lower smoke emission than the pure polymer. The partial substitution of ATH by MP led to a further increase in the LOI but the earlier ignition of the material measured by cone calorimetry. Moreover, less smoke is released for EVM–ATH–MP than for EVM–ATH. The fire retardant mechanism was investigated for EVM–ATH and EVM–ATH–MP to evaluate the role of MP in the material. The dispersion of the additives was examined by scanning electron microscopy (SEM) showing that all additives are homogenously dispersed in the matrix. The thermal decomposition, the condensed and the gas phase mechanism of both materials was investigated using thermogravimetric analysis (TGA), a mass loss calorimeter coupled with a Fourier transform infrared spectrometer (MLC-FTIR), pyrolysis-gas chromatography-mass spectrometry (py-GCMS), and the solid state nuclear magnetic resonance (NMR) of 13C, 27Al and 31P. It was shown that both materials are protected by a gas and condensed phase mechanism. The endothermic decomposition of ATH has a cooling effect and dilutes the fuel through the release of water. In the condensed phase, it was found that both materials are protected through the formation of a physical barrier. It is evidenced that the barrier formed for EVM–ATH–MP exhibits higher insulative properties than that of EVM–ATH.

  • recent advances in the use of zinc borates in flame retardancy of eva
    Polymer Degradation and Stability, 1999
    Co-Authors: Serge Bourbigot, Michel Le Bras, Robert Leeuwendal, Kelvin K Shen, David M Schubert

    Abstract:

    Abstract In this work, zinc borates are used as synergistic agents in EVA–ATH and EVA–Mg(OH) 2 flame-retardant (FR) formulations and as smoke suppressants. Moreover, the study by solid state NMR of the residues sampled at different times during cone calorimeter experiments of the formulations EVA–ATH and EVA–ATH/Zinc borate allows to propose a mechanism of action of the FR systems. It is demonstrated that the decomposition of Aluminium Trihydroxide (ATH) to Al 2 O 3 during the heating of the polymer results in an increase of the ignition time. Moreover the formation of Al 2 O 3 in situ from ATH during the combustion of the polymer is the first event. Concurrently zinc borate degrades and it is proposed that a vitreous protective coating is created, which yields a more efficient char.

Halimaton Hamdan – One of the best experts on this subject based on the ideXlab platform.

  • Effect of silica aerogel – Aluminium Trihydroxide hybrid filler on the physio-mechanical and thermal decomposition behaviour of unsaturated polyester resin composite
    Polymer Degradation and Stability, 2020
    Co-Authors: Zulhelmi Alif Abdul Halim, Muhamad Azizi Mat Yajid, Fajar Anugrah Nurhadi, Norhayati Ahmad, Halimaton Hamdan

    Abstract:

    Abstract Aluminum Trihydroxide (ATH) is an eco-friendly and economical additive used in polymers as a flame retardant (FR), but its low thermal stability has become an important issue that is critical in determining the fire protection and thermal stability of the composites. The present study was an attempt to enhance the thermal stability of ATH to some extent by combining it with nano-porous silica known as silica aerogel (SA) as a hybrid FR filler in unsaturated polyester resin (UPR). Ultra-low density SA (0.07 g/cm3) in the form of fine particles was extracted from renewable resources (i.e. rice husk), through a sol-gel process, surface modification and dried at atmospheric pressure. From our findings, it is found that the addition of the hybrid filler into UPR results in interesting properties such as lightweight, flame retardancy and enhanced thermal stability whose properties cannot be gained by composites with single filler. From thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and gas analysis using Fourier transform infrared spectroscopy (FTIR); it is evident that doping the ATH with SA helps to improve the thermal stability via synergistic effect, by extending the ATH decomposition process over a wider temperature range. As a result, the UPR filled with SA/ATH hybrid demonstrates higher thermal stability when compared to the composites filled with only ATH or SA. Furthermore, the SA/ATH hybrid also provides sufficient flame retardancy in UPR as evaluate by ASTM D635-14 (UL–94) horizontal burning test. For mechanical properties, a sharp increase in tensile strength was observed for UPR filled with ATH or SA while the addition of SA/ATH hybrid filler only slightly increases the tensile properties of UPR due to particle agglomerations and porosities.

  • effect of silica aerogel Aluminium Trihydroxide hybrid filler on the physio mechanical and thermal decomposition behaviour of unsaturated polyester resin composite
    Polymer Degradation and Stability, 2020
    Co-Authors: Zulhelmi Alif Abdul Halim, Muhamad Azizi Mat Yajid, Fajar Anugrah Nurhadi, Norhayati Ahmad, Halimaton Hamdan

    Abstract:

    Abstract Aluminum Trihydroxide (ATH) is an eco-friendly and economical additive used in polymers as a flame retardant (FR), but its low thermal stability has become an important issue that is critical in determining the fire protection and thermal stability of the composites. The present study was an attempt to enhance the thermal stability of ATH to some extent by combining it with nano-porous silica known as silica aerogel (SA) as a hybrid FR filler in unsaturated polyester resin (UPR). Ultra-low density SA (0.07 g/cm3) in the form of fine particles was extracted from renewable resources (i.e. rice husk), through a sol-gel process, surface modification and dried at atmospheric pressure. From our findings, it is found that the addition of the hybrid filler into UPR results in interesting properties such as lightweight, flame retardancy and enhanced thermal stability whose properties cannot be gained by composites with single filler. From thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and gas analysis using Fourier transform infrared spectroscopy (FTIR); it is evident that doping the ATH with SA helps to improve the thermal stability via synergistic effect, by extending the ATH decomposition process over a wider temperature range. As a result, the UPR filled with SA/ATH hybrid demonstrates higher thermal stability when compared to the composites filled with only ATH or SA. Furthermore, the SA/ATH hybrid also provides sufficient flame retardancy in UPR as evaluate by ASTM D635-14 (UL–94) horizontal burning test. For mechanical properties, a sharp increase in tensile strength was observed for UPR filled with ATH or SA while the addition of SA/ATH hybrid filler only slightly increases the tensile properties of UPR due to particle agglomerations and porosities.

Christelle Delaite – One of the best experts on this subject based on the ideXlab platform.

  • ethylene vinyl acetate copolymer Aluminium Trihydroxide composites a new method to predict the barrier effect during cone calorimeter tests
    Polymer Degradation and Stability, 2015
    Co-Authors: Florian Cavodeau, Rodolphe Sonnier, Belkacem Otazaghine, Josemarie Lopezcuesta, Christelle Delaite

    Abstract:

    Abstract This study presents the use of oedometric compression test in order to evaluate the breakdown of a protective layer acting as a diffusion barrier (“barrier effect”) occurring during cone calorimeter tests for ethylene-vinyl acetate copolymer/Aluminium Trihydroxide (EVA/ATH) composites. The formation of an alumina layer at the sample surface during burning insulates thermally the underlying material and reduces the heat release rate. The efficiency of this barrier depends on the cohesion of the layer formed. This cohesion depends on the ability of the particles (ATH and synergistic mineral fillers) to self-arrange. During the test, the breakdown of this barrier can lead to an increase in HRR. The oedometric compression test allows assessing the ability of fillers to form a cohesive layer. Results obtained from compression modulus of filler powders are directly related to some aspects of the heat release rate curve of composites measured in cone calorimeter tests. Indeed, the appearance and the intensity of the second pHRR (related to the breakdown of the barrier layer) in cone calorimeter test are related to the slope of oedometric compression curve.

  • Ethylene-vinyl acetate copolymer/Aluminium Trihydroxide composites: A new method to predict the barrier effect during cone calorimeter tests
    POLYMER DEGRADATION AND STABILITY, 2015
    Co-Authors: Florian Cavodeau, Rodolphe Sonnier, Belkacem Otazaghine, Jose-marie Lopez-cuesta, Christelle Delaite

    Abstract:

    This study presents the use of oedometric compression test in order to evaluate the breakdown of a protective layer acting as a diffusion barrier (”barrier effect”) occurring during cone calorimeter tests for ethylene-vinyl acetate copolymer/Aluminium Trihydroxide (EVA/ATH) composites. The formation of an alumina layer at the sample surface during burning insulates thermally the underlying material and reduces the heat release rate. The efficiency of this barrier depends on the cohesion of the layer formed. This cohesion depends on the ability of the particles (ATH and synergistic mineral fillers) to self-arrange. During the test, the breakdown of this barrier can lead to an increase in HRR. The oedometric compression test allows assessing the ability of fillers to form a cohesive layer. Results obtained from compression modulus of filler powders are directly related to some aspects of the heat release rate curve of composites measured in cone calorimeter tests. Indeed, the appearance and the intensity of the second pHRR (related to the breakdown of the barrier layer) in cone calorimeter test are related to the slope of oedometric compression curve.