Dissertations / Theses on the topic 'Flamme – Essais'
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Ramgobin, Aditya. "Synthèse et conception de retardateurs de flamme intelligents." Electronic Thesis or Diss., Université de Lille (2018-2021), 2019. http://www.theses.fr/2019LILUR045.
Polymeric materials have been increasingly used as replacement for other types of materials such as ceramics or metals. However, most polymers have a serious drawback: they need to be fire retarded. Nevertheless, thanks to advanced research in the field, high performance materials that resist high temperatures and fire scenarios have been developed. While these materials have extremely enviable properties, they are also very expensive. The aim of this PhD is to understand the fire behavior of high-performance polymers and design fire retardants that would mimic these high-performance materials under extreme heat or fire. To do so, the thermal and fire behavior of three high performance materials were studied: polyetheretherketone (PEEK), polyimide (PI), and polybenzoxazole (PBO). Their thermal decomposition pathways were evaluated thanks to high temperature analytical techniques like pyrolysis-GC/MS and TGA-FTIR. Model based kinetics of the thermal decomposition of these polymeric materials were also elucidated by using dynamic TGA under three different atmospheres (nitrogen, 2% oxygen, and air). These provided insight regarding the thermal behavior high performance polymers, which were used to conceptualize novel potential fire retardants. Therefore, a series of fire retardants that have demonstrated similar behaviors as high performance polymers in fire scenarios were synthesized. These fire retardants include a Schiff base: salen and its derivatives, as well as some of their metal complexes. The thermal behavior and fire performances of these fire retardants were evaluated in two polymeric materials using a relatively low loading (< 10 wt%): thermoplastic polyurethane, and polyamide 6. While some of the fire retardants had little effect, in terms of fire retardancy, some candidates showed a significant improvement in terms of peak of heat release rate. This reverse approach towards designing fire retardants has shown some promise and can be used as a complementary method for the design of high-performance materials at lower cost
Ramgobin, Aditya. "Synthèse et conception de retardateurs de flamme intelligents." Thesis, Lille 1, 2019. http://www.theses.fr/2019LIL1R045/document.
Polymeric materials have been increasingly used as replacement for other types of materials such as ceramics or metals. However, most polymers have a serious drawback: they need to be fire retarded. Nevertheless, thanks to advanced research in the field, high performance materials that resist high temperatures and fire scenarios have been developed. While these materials have extremely enviable properties, they are also very expensive. The aim of this PhD is to understand the fire behavior of high-performance polymers and design fire retardants that would mimic these high-performance materials under extreme heat or fire. To do so, the thermal and fire behavior of three high performance materials were studied: polyetheretherketone (PEEK), polyimide (PI), and polybenzoxazole (PBO). Their thermal decomposition pathways were evaluated thanks to high temperature analytical techniques like pyrolysis-GC/MS and TGA-FTIR. Model based kinetics of the thermal decomposition of these polymeric materials were also elucidated by using dynamic TGA under three different atmospheres (nitrogen, 2% oxygen, and air). These provided insight regarding the thermal behavior high performance polymers, which were used to conceptualize novel potential fire retardants. Therefore, a series of fire retardants that have demonstrated similar behaviors as high performance polymers in fire scenarios were synthesized. These fire retardants include a Schiff base: salen and its derivatives, as well as some of their metal complexes. The thermal behavior and fire performances of these fire retardants were evaluated in two polymeric materials using a relatively low loading (< 10 wt%): thermoplastic polyurethane, and polyamide 6. While some of the fire retardants had little effect, in terms of fire retardancy, some candidates showed a significant improvement in terms of peak of heat release rate. This reverse approach towards designing fire retardants has shown some promise and can be used as a complementary method for the design of high-performance materials at lower cost
Kolb, Gilles. "Etude d'une flamme non prémélangée caractéristique d'un incendie en présence d'un écoulement forcé." Poitiers, 1996. http://www.theses.fr/1996POIT2291.
Samyn, Fabienne. "Compréhension des procédés d'ignifugation du polyamide 6 : apport des nanocomposites aux systèmes retardateurs de flamme phosphorés." Lille 1, 2007. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2007/50376-2007-Samyn.pdf.
Coudoro, Kodjo. "Etude expérimentale et modélisation de la propagation de flammes en milieu confiné et semi confiné." Thesis, Orléans, 2012. http://www.theses.fr/2012ORLE2005.
The context of the current study is the assessment of the occurrence of flame acceleration in accidental situations. The methodology developed for the assessment of hydrogen hazard in the nuclear industry led to the definition of a criterion for the prediction of the acceleration potential of a hydrogen/air/dilutant mixture based on its properties. This study aims to extend this methodology to gaseous mixtures that can be encountered in the classical industry. Therefore, three mixtures were chosen: the first two are representatives of a natural gas/air mixture: G27 (82%CH4/18%N2) and G222 (77%CH4/23%H2). The third one is a H2/CO (50%H2/50%CO) mixture and represents the Syngas. During this work, flammability limits were measured at 300 K and two initial pressures (1 and 2 bar) for each mixture. Fundamental flame speeds and Markstein lengths were also measured at three initial temperatures (300, 330, 360 K) and 2 initial pressures (1 and 2 bar) for each mixtures. A kinetic modeling was performed based on three detailed kinetic models and allowed the calculation of the global activation energy on the basis of the kinetic model which showed the best agreement with the experimental data. The acceleration potential for each mixture in presence of obstacles has then been investigated. It was found that different criteria were to be applied depending on whether the flame is stable or not. A predicting criterion was proposed in both case
Drevelle, Christophe. "Conception et développement de systèmes retardateurs de flamme pour fibres synthétiques." Lille 1, 2005. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2005/50376-2005-Drevelle.pdf.
Audouin, Laurent. "Etude de la structure d'une flamme simulant un incendie de produits industriels : caractérisation et modélisation de cas réels de feux." Poitiers, 1995. http://www.theses.fr/1995POIT2354.
Chantegraille, Denis. "Optimisation de systèmes retardateurs de flamme pour des applications à des matériaux polymères à haute durabilité photochimique." Clermont-Ferrand 2, 2009. http://www.theses.fr/2009CLF21918.
Laoutid, Fouad. "Développement de nouveaux systèmes retardateurs de flamme utilisant des composés minéraux et organo-minéraux dans le polyéthylène térephtalate recyclé." Montpellier 2, 2003. http://www.theses.fr/2003MON20008.
Giraud, Stéphane. "Microencapsulation d'un diisocyanate et d'un phosphate d'ammonium : application : élaboration d'un systè́me polyuréthane monocomposant à propriété retardatrice de flamme pour l'enduction textile." Lille 1, 2002. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2002/50376-2002-311-312.pdf.
L'incorporation dans une formulation PU de phosphate d'ammonium encapsulé avec une membrane imperméable peut donner un caractère FR permanent à l'enduit. Cette étude est consacrée à la mise au point de procédés de microencapsulation, principalement selon la technique par polymérisation interfaciale, pour l'isophorone diisocyanate (IPDI) et pour le diammonuim hydrogénophosphate (DAHP). Différents paramètres expérimentaux ont étés maitrisés afin de donner aux deux types de microcapsules les caractéristiques déterminantes pou leur application : contrôle de leur taille, de leurs propriétés thermomécaniques et de la perméabilité de leur membrane. Après l'étude de la réactivité d'un mélánge microcapsules d'IPDI - polyol, nous sommes parvenus à synthétiser un PU solide avec une température de réaction peu élevée (80°C). Les microcapsules de DAHP donnent aux enduits PU appliqués sur tissu coton un réel effet retardateur de flamme, même si le char développé avec les microcapsules résiste un peu moins bien à la chaleur que celui avec le DAHP pur
Hu, Chi. "Flame retardancy of polybutylene succinate by multiple approaches." Thesis, Lille, 2018. http://www.theses.fr/2018LIL1R073.
This study was dedicated to the development of flame retarded polybutylene succinate (PBS), a bio-based polymer, which possess good mechanical properties and biodegradability, by various different approaches. In this context, modifications of isosorbide were achieved to obtain bio-based flame retardants. Then isosorbide and poly(isosorbide) carbonate (PIC) were blended with PBS and APP to form intumescent flame retardant system acting as carbonization agent. It shows the improvement of the flame retardant properties in the condensed phase where the yield of residual char was increased and the pHRR and THR were decreased. A conventional flame retardant, DOPO, showed some super flame retardant property for PBS in the gaseous phase. It had an improvement of the ignition time from 119 s to 410 s in MLC test when 10 wt% of DOPO was incorporated in PBS. An original UL-94 instrumentation was designed to investigate its mode of action during a fire scenario. These studies have provided the information for the future works on flame retardancy of bio-based polymers
Schuhler, Eliot. "Dégradation des matériaux composites sous l'effet d'une flamme : application à la réaction aux feux des composites utilisés pour les transports et l'énergie Behaviour of aeronautical polymer composite to flame: a comparative study of thermoset- and thermoplastic-based laminate." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMIR27.
Carbone fibers reinforced polymers offer many advantages in terms of weight, fatigue resistance or corrosion in the aerospace industry. However, the use of new materials such as thermosetting matrix composites requires a significant effort of development, testing and validation. In particular in the field of fire resistance. This work focuses on the experimental characterization of fire resistance for different types of composite materials using a flame burner. The first part of the study deals with the characterization of the heat flux during the flame impingement. In a second step, the response to this thermal stress is measured for different composite materials. For both parts of this study, the experimental results are compared to the results obtained from numerical simulations with OpenFoam
Jeanjean, Samuel. "Les carburants métalliques comme futurs vecteurs énergétiques décarbonés." Electronic Thesis or Diss., Orléans, 2024. http://www.theses.fr/2024ORLE1006.
The climate emergency demands immediate action to combat global warming and its devastating consequences. This entails actively promoting sustainable transportation and clean energy sources to create a climate-responsible future. Although there are already many carbon-free energy sources, most of them are intermittent, necessitating the use of energy vectors to make these solutions viable. These energy vectors allow for the storage of surplus energy to smooth out energy production, according to demand. An excellent candidate to serve as such an energy vector is aluminum. In this context, the study of aluminum powder combustion becomes crucial.The objective of this thesis is to advance the understanding of the physical phenomena governing this reaction, with a particular focus on flame temperature. To study this characteristic, a Bunsen-type burner was used, and a two-color pyrometric system was employed to acquire temperature mapping. A transition in flame mode was observed in an aluminum/methane/air mixed flame by studying flame intensity, flame structure, and flame thickness. Additionally, on the same burner, the flammability limit, flame speed, and temperature were observed for different oxygenation rates in an aluminum/air flame
Lesaffre, Nicolas. "Ageing of flame retarded polylactic acid." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10098/document.
This work deals with the ageing of flame retarded (FR) Polylactic acid (PLA). The impact of three accelerated ageing conditions i.e. temperature/ultra-violet (T/UV), temperature/relative humidity (T/RH) and temperature/ultra-violet/relative humidity (T/UV/RH) was studied. In order to understand the role of fire retardant additives on ageing of flame retarded PLAs, the first study was focused on neat PLA. Innovative methodologies were developed, the change in physico-chemical properties of the polymer was characterized as a function of ageing exposure and ageing duration. Moreover, the mechanisms of degradation occurring during T/UV, T/RH and T/UV/RH exposure were elucidated and compared to the literature. Then, the influence of flame retardants (i.e. Melamine, Ammonium polyphosphate and Cloisite 30B) on the ageing behavior of FR-PLAs was investigated. FR fillers were evidenced to have a direct influence on physico-chemical properties and mechanisms of degradation of the material during ageing. The molecular mass was reported to be a crucial parameter, as it is related to the physico-chemical properties and thus to the durability of the material. The main goal of flame retardants is to improve the flammability of PLA thus the effect of ageing on the fire properties of PLA was determined. It is noteworthy that the fire properties of flame retarded PLA are improved during ageing, until the complete degradation of the materials. These surprising performances were found to be correlated to the change in physico-chemical properties which play a key role on the kinetics of intumescence
Hu, Chi. "Flame retardancy of polybutylene succinate by multiple approaches." Electronic Thesis or Diss., Université de Lille (2018-2021), 2018. http://www.theses.fr/2018LILUR073.
This study was dedicated to the development of flame retarded polybutylene succinate (PBS), a bio-based polymer, which possess good mechanical properties and biodegradability, by various different approaches. In this context, modifications of isosorbide were achieved to obtain bio-based flame retardants. Then isosorbide and poly(isosorbide) carbonate (PIC) were blended with PBS and APP to form intumescent flame retardant system acting as carbonization agent. It shows the improvement of the flame retardant properties in the condensed phase where the yield of residual char was increased and the pHRR and THR were decreased. A conventional flame retardant, DOPO, showed some super flame retardant property for PBS in the gaseous phase. It had an improvement of the ignition time from 119 s to 410 s in MLC test when 10 wt% of DOPO was incorporated in PBS. An original UL-94 instrumentation was designed to investigate its mode of action during a fire scenario. These studies have provided the information for the future works on flame retardancy of bio-based polymers
Vannier, Aurore. "Procédés d'ignifugation du poly(éthylène téréphtalate) - application textile : synergie entre OMPOSS et retardateur de flamme phosphoré." Thesis, Lille 1, 2008. http://www.theses.fr/2008LIL10039/document.
This study proposes to f1ame retard PET by the incorporation of a phosphorous based fia me retardant (OP950) and nanoparticles (LDH, MWNT, OMPOSS). Whereas the synthesized LDH lead to the degradation of PET, MWNT and OMPOSS bring an improvement in the f1ame retarding properties. A synergistic effect is observed when OMPOSS are added simultaneously with OP950 (bringing intumescence). This effect is due to physical phenomena such as the sublimation of the POSS. The study of the degradation of the different components of the blend revealed the formation of phosphate based species or silica, that do not react with each other or with the polymer. The improvement of the fire properties is then attributed to the formation of phosphorous components acting as a barrier between the polymer and the f1ame. It is proposed that silica reinforce the mechanical properties of the char, and that the gaseous components act as blowing agent. The feasibility of the spinning has been studied and fibres elaborated in spite of the poor dispersion of the additives into the polymer matrix. A masterbatch has been industrially prOOuced from this study by industrial partner. The non-wovens manufactured with those fibres show goOO fire retarding properties. They pass a number of normalized tests. This masterbatch is now commercialized
Delaval, Damien. "Développement et caractérisation de systèmes intumescents retardateurs de flamme pour polypropylènes recyclés issus des véhicules usagés." Electronic Thesis or Diss., Lille 1, 2009. http://www.theses.fr/2009LIL10015.
The impact of recycling and pollutants (engine oil (EO) and ethylene glycol (EG)) on the intrinsic properties of polypropylene-based materials coming from end-of-life cars was investigated. Recycling (limited here to six extrusion cycles) is not detrimental to the mechanical properties of the polymeric matrices. The crystallization kinetics study realized on the polluted polymers showed that the presence of EG delays crystallization. The degradation kinetics allowed to simulate and quantify the different degradation steps of the materials. Pollutants and recycling also lead to an improvement of the reaction to fire of our copolymer, especially in the case of EO-containing samples. The second part of the work was devoted to the study of the flame retardant properties of our materials provided by ammonium polyphosphate (APP) with or without zinc borate (ZB) (synergistic agent)). In all cases recycled and polluted materials show satisfying performances. It was found that the efficiency of the protective barrier provided by the char is governed by the rapidity of its formation and its thermal conductivity which are positively influenced by EO (with APP/ZB) and recycling (with APP) (increase of the formation rate and decrease of the conductivity). Chemical characterization of the structures formed in a fire scenario reveals the formation of a phosphocarboneous structure containing polyaromatics, pyrophosphates and phosphoric acid and when zinc borate is used, borophosphates which can reinforce the intumescent structure
Gérard, Caroline. "Contribution of nanoparticles to the flame retardancy of epoxy resins." Thesis, Lille 1, 2011. http://www.theses.fr/2011LIL10034/document.
This thesis aims at flame-retarding an epoxy resin through the use of nanoparticles. Incorporation of Polyhedral Oligomeric Silsesquioxane (POSS) or carbon nanotubes alone in the matrix provides little enhancement of the reaction to fire. The covalent functionalization of carbon nanotubes by grafting fire-retardant moieties has been carried out and characterized, but it does not enhance the reaction to fire of the epoxy matrix filled with carbon nanotubes. The combination between a phosphorus-based flame-retardant (APP) and carbon nanotubes reveals an antagonistic effect between these two fillers. On the contrary, using POSS in combination with APP provides a synergy. The study of the thermal degradation of these systems shows that the interactions between these fillers modify the viscosity of the degraded matrix. The trapping of degradation gases is enhanced in the case of APP/POSS, which results in the creation of a protective layer earlier than with the reference system containing APP alone. Furthermore, the presence of POSS permits the creation of silicophosphates which reinforce the residue. On the contrary, the residue of the formulation containing carbon nanotubes is excessively stiff and it cracks during combustion, hindering the proper formation of the protective layer
Delaval, Damien. "Développement et caractérisation de systèmes intumescents retardateurs de flamme pour polypropylènes recyclés issus des véhicules usagés." Thesis, Lille 1, 2009. http://www.theses.fr/2009LIL10015/document.
The impact of recycling and pollutants (engine oil (EO) and ethylene glycol (EG)) on the intrinsic properties of polypropylene-based materials coming from end-of-life cars was investigated. Recycling (limited here to six extrusion cycles) is not detrimental to the mechanical properties of the polymeric matrices. The crystallization kinetics study realized on the polluted polymers showed that the presence of EG delays crystallization. The degradation kinetics allowed to simulate and quantify the different degradation steps of the materials. Pollutants and recycling also lead to an improvement of the reaction to fire of our copolymer, especially in the case of EO-containing samples. The second part of the work was devoted to the study of the flame retardant properties of our materials provided by ammonium polyphosphate (APP) with or without zinc borate (ZB) (synergistic agent)). In all cases recycled and polluted materials show satisfying performances. It was found that the efficiency of the protective barrier provided by the char is governed by the rapidity of its formation and its thermal conductivity which are positively influenced by EO (with APP/ZB) and recycling (with APP) (increase of the formation rate and decrease of the conductivity). Chemical characterization of the structures formed in a fire scenario reveals the formation of a phosphocarboneous structure containing polyaromatics, pyrophosphates and phosphoric acid and when zinc borate is used, borophosphates which can reinforce the intumescent structure
Santandrea, Audrey. "New insights on the explosion severity of nanopowders : a nano-grain of sand in the gears of the standards." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0104.
The small size of nanoparticles implies a high specific surface area, which induces original properties when compared to micropowders, such as chemical, mechanical, optical or biological properties. Among these new specificities, nanoparticles are subjected to weak cohesion forces, such as van der Waals, electrostatic or capillary forces, which cause them to agglomerate in a reversible way. However, dust explosions require the dispersion of the dust in the air, which can lead to a breakage of these agglomerates. The aim of this work is then to study the influence of nanoparticles specificities, notably the agglomeration, on their ignition sensitivity and explosion severity, and evaluate the adequacy of the international standard methods to determine these parameters when it comes to nanoparticles. Four types of powders were chosen to highlight the specific behavior of each type of combustible powder: carbon black, nanocellulose, aluminum and carbon-coated silicon. The powders were characterized by Scanning Electron Microscopy (SEM), specific surface measurement and helium pycnometer, and their particle size distribution (PSD) was measured before and after dispersion using different methods. The mean surface diameter, used to consider the high surface area of nanoparticles, considerably decreases after the injection in the 20L sphere, i.e the standard equipment to measure the explosion severity of a dust. This observation highlighted the necessity to characterize the dust after injection in the 20L sphere, to accurately evaluate the explosion risk. Ignition and explosion tests were conducted in standard conditions, but also by varying the powder preparation (aging, drying, sieving, agglomeration), and the operating conditions (dispersion procedure, ignition energy, initial turbulence). Specific behaviors related to the powder nature (carbonaceous, organic or metallic) were then observed, discussed, and alternative measurement methods were proposed. For instance, alternative dispersion nozzles were tested to provide a better cloud homogeneity or to reproduce industrial release conditions. Dispersion procedure and ignition source should be adapted to the minimum ignition energy of the nanopowders to avoid both pre-ignition and overdriving. Variation of the ignition delay time can be helpful to obtain the most conservative results. One of the main proposals consists in the consideration of the laminar burning velocity as a standard characteristic of the explosion severity. Experiments were conducted in a flame propagation tube and a vented 20L sphere to evaluate the unstretched burning velocity of nanocellulose. The results were then compared to an existing correlation based on the pressure-time evolution during standard experiments. Furthermore, a flame propagation model, initially designed for hybrid mixtures, was adapted to the flame propagation in a cloud of organic nanoparticles, showing consistent results with the experiments
Lin, Qing. "Développement de systèmes retardateurs de flamme pour matériaux composites thermoplastiques à fibres continues." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0118.
The present demand of polymer-matrix composite materials in the transport market is significantly increasing, to replace the work-pieces actually manufactured in metal alloys, the polymer-matrix composite being lighter and more performant. Thermoset composites are currently and widely used however this kind of composites presents a severe drawback due to their non- recyclable character. One of the objectives of the “Résines idéales” project and of this thesis is to develop new composites made from thermoplastic matrix, endowed with similar properties. Among them, the fire behavior is a major challenge and the aim of this work is to develop new flame retardant systems for thermoplastics composites reinforced with continuous fibers. Firstly, we have performed a screening of potentially effective phosphorus flame retardants. Also, we have studied the influence of the reinforcement taffetas on the thermal stability and fire behavior. For that, various tests have been performed such as cone calorimeter, LOI and UL-94. Then, to improve the fire behavior and particularly to satisfy the aeronautical fire standards (the most challenging), we have studied binary and ternary mixtures of flame retardants constituted by the selected phosphorus flame retardant and other additives: alumina, aluminum hydroxide (ATH), expanded graphite and 9,10-dihydro-9-oxy-10-phosphaphenanthrene-10-oxide (DOPO). In each case, the thermal stability and fire behavior have been characterized and discussed
Moustafa, Hesham. "Influence des nanoparticules lamellaires sur la resistance au feu d'un EPDM renforcé et de ses assemblages bicouches." Mulhouse, 2013. http://www.theses.fr/2013MULH4093.
The purpose of this study is to elucidate the effect of the interfacial strength in bilayer assemblies on the fire behavior of flame resistant, FR, materials. Thus, a montmorillonite (MMT) clay was selected as FR agent, synthesised and modified by long chain alkyl surfactant at three different levels 1, 2 and 4 CEC. With increasing modification level, clay-polymer (EPDM-g-MA) blends changes from microcomposite to nanocomposite structure in which the clay is exfoliated. Crosslinking reaction was performed using peroxide except for the composite containing unmodified clay which has been crosslinked under electron beam. The progress of the crosslinking process has been monitored by low field DQ 1H-NMR. The results were associated with swelling results and the dynamic mechanical behavior. The assembling protocol of two polymer layers has been chosen to allow the control of their gradually increasing interfacial strength, starting from the contribution of pure van der Waals interfacial interactions in fully pre-crosslinked layers up to the full contribution of interdiffusion/co-crosslinking mechanisms in assemblies without any pre-crosslink. The FR behavior was measured by a cone calorimeter. The efficiency of exfoliated clay has been demonstrated. The performances of bilayers were surprisingly found unaffected by the interfacial strength. FR performance increased with the content of exfoliated clay up to 5 phr (necessary amount to form an efficient thermal shield). Thereafter the enhancement decreases. It has been shown that the FR behavior of the composites is primarily governed by the number of exfoliated platelets in the polymer layer not by the layer thickness as such
Viretto, Amandine. "Influence de la morphologie sur la dégradation thermique et le comportement au feu de formulations polymères complexes en vue d'applicationsen en câblerie." Thesis, Montpellier 2, 2013. http://www.theses.fr/2013MON20045.
The cable industry is a major consumer of industrial polymers. In this area, the standards impose to limit the fire risk and thus to enhance the fireproof of the polymeric materials which are important sources of fuel. Many studies have focused on their flame retardancy by using additive flame retardants, but few of them have studied the influence of the morphology of filled polymer blends on the thermal stability and the fire behavior. This thesis follows a previous project which demonstrated a significant influence of the morphology on the fire behavior of a binary polymer blend (PC / PBT). It aims to improve the understanding of this influence in the case of more complex formulations (ternary or quaternary) with ethylene methylacrylate (EMA) matrix. The first strategy was the identification of a flame retardant system including polyester that is able to char when a flame retardant is added. Once the system is identified (PBT + MDH), it was incorporated in EMA matrix by varying the composition and the morphology (selective dispersion, particle size ...). This approach showed significant differences between the different formulations and very interesting results have been obtained in terms of fire reaction at the laboratory scale. However, the scale-up approach (flame spread test) did not validate these formulations for cables applications. Therefore, the last part has been proposed to try to improve the cohesion of the residue by adding ammonium polyphosphate
Colombiano, Jérémy. "Approche multi-échelle pour la caractérisation de la réaction au feu sur un matériau bois. Développement d'une méthodologie pour l'ingénierie de la sécurité incendie. Validation of a Pyrolysis Model of Wood Thermal Decomposition under Cone Calorimeter." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2020. http://www.theses.fr/2020ESMA0017.
Increasingly, fire safety relies on fire safety engineering. This involves, in particular, using calculation codes, performing numerical simulations aimed at defining the safety rules to be applied. Thus, numerous studies have made it possible to improve the calculation codes and define the bases and technical guides to be respected for carrying out these studies. However, while this is true in the field of fire resistance, evacuation or smoke control, it is not yet the case in the field of reaction to fire. The latter represents how the material will behave as a fuel and it characterizes the ability of that material to ignite and contribute to a fire.In this context, the objective of this thesis work is to study and predict the kinetics of thermal decomposition, combustion and flame propagation of wood material. For this, the working method adopted is multi-scale, both experimental and digital. This approach allows initially to simplify the phenomena in order to determine the properties of the material, then to add complexity on an increasing scale, in order to identify the processes controlling the propagation of flame and to define the bases for an engineering study. In total, 4 working scales were studied:- At a small scale, which concerns only the solid phase. It permits to extract some properties of the material by working on samples of the order of a milligram. The properties extracted are the thermal and kinetic properties, essential to characterize the heating and thermal decomposition of the material on a larger scale.- At medium scale, including the influence of the gas phase within particularly the development of the flame on the surface of the sample. The samples are of the order of a hundred grams with a thickness identical to the final application of the product. The objective is first to identify the combustion parameters of the material, such as the heat of combustion, the rate of formation of soot, carbon monoxide, etc. Secondly, it concerns the numerical validation of all the properties extracted (thermal, kinetic and combustion properties) by comparison with the experimental data (rate of heat release, loss of mass, temperatures, etc. ).- At the intermediate scale, using samples of the order of one kilogram. It takes into account the propagation of flame on the surface of the sample. Therefore, the processes driving this propagation are studied. This scale is used to assess the ability of the code to predict the kinetics of flame propagation. Two modes of propagation are investigated: counter-current and co-current. This scale also makes it possible to establish certain bases for carrying out a reaction to fire engineering study.- At final scale, two studied modes of propagation are coupled. The objective is then to validate the observations made at the previous scale and to support the basis for an engineering study
Tibiletti, Lucie. "Nouvelles formulations de résines polyesters insaturés pour l’amélioration du comportement au feu." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20134.
Unsaturated polyesters are thermoset resins particularly appreciated for their low cost and easy processing. Nevertheless one of their main drawbacks is their poor fire resistance. The aim of this PhD thesis was to prepare new resin formulations with an improved fire behaviour. The first part of this work was dedicated to the grafting of phosphorous monomers in the polyester matrix. Methacrylic and styrenic monomers were synthesized and used to replace of part of the styrene in the resin. Resin thermal stability was decreased, but on the whole their fire behaviour was improved. Condensed phase and gas phase effects of phosphorus were highlighted.In a second part, a screening of various kinds of particles with different sizes was performed. Calorimetric tests revealed that, while the effect of these particles used alone is limited, a decrease of resin flammability could be achieved with specific combinations. Finally, commercial phosphorous additives were associated with submicronic fillers. From all the additives tested, ammonium polyphosphate stands out, with a powerful impact on the resin fire reaction and especially a much increased charring. However, its combination with inorganic particles was not conclusive
Lhuillier-Marchand, Alexis. "Propagation des feux de végétation : expérimentations à l’échelle du laboratoire et validation d’un propagateur." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0131/document.
This work is devoted to the experimental and numerical study of wildland fire spread at laboratory scale. A tracking fire front method using visible cameras was used in order to follow the fire front positions during the propagation and to evaluate some fire front properties. The data include the Rate Of Spread (ROS), the fire front width, the length of fire, the profile of flames and the Heat Release Rate. An experimental campaign of 105 fire spread tests with wood shaving as fuel was conducted on the PROMETHEI plateform (Plateforme de Recherche Opérationnelle en Métrologie Thermique dédiée aux Essais Incendies) of the laboratory LEMTA. This campaign was essentially focused on the effect of the fuel bed width and the fuel loading on the fire dynamics (particularly on the ROS and fire width). An open-source data base provides the positions of the front and backing fire as a function of time. A fire spread model based on the small world concept with a hexagonal cell network was developed. Two approaches were studied: the first one is based on a radiative transfer model for the definition of the cell states and the other one is based on an estimated distribution function. A particle swarm optimization (PSO) algorithm was used for the identification of the different parameters of the model using the experimental results. Then, the model was compared to other experiments included fuel breaks or narrowing/widening of the fuel bed width
Gossiaux, Alexandre. "Comportement au feu de mousses polyuréthanes rigides : Approches systématiques." Electronic Thesis or Diss., Centrale Lille Institut, 2021. http://www.theses.fr/2021CLIL0021.
A common awareness of environmental factors and more particularly of global warming makes it urgent to better control energy consumption. One solution is to reduce energy loss in building using new and efficient thermal insulation materials such as polymeric foams. Polyurethane (PUR) and polyisocyanurate (PIR) foams are very effective and competitive materials due to their low cost. However, these materials are extremely flammable due to their organic nature. Researchers and manufacturers add molecules called flame retardants (FRs) to their composition in order to prevent the outbreak of a fire or reduce the intensity of combustion when a fire breaks out. The objective of this PhD work is to study by systematic approaches the fire behavior of PUR and PIR foams. The aim is to propose a scientific approach allowing a quicker and more efficient development of new formulations. This systematic study was also coupled with a multi-scale study of the fire behavior of the foams, as a laboratory-scale fire test was developed (M-SBI), which allowed a quick and efficient examination of the formulations. The FRs studied in this work are phosphorus organic FRs which are currently promoted to replace some halogenated FRs which could be dangerous for the environment and health. The mechanisms of degradation of virgin and flame retarded foams were elucidated using various analytical tools. Thus, in the case of phosphorus FRs, we were able to demonstrate that their mode of action varied according to the phosphorus oxidation degree as well as according to their point of decomposition. Moreover, the efficiency of the FRs also varies according to the foam used (PUR or PIR). All these results can thus advantageously be exploited to propose future efficient flame retardants for specific systems to reduce the combustion intensity of the foams
Juniper, Matthew. "Structure et stabilisation des flammes cryotechniques." Châtenay-Malabry, Ecole centrale de Paris, 2001. http://www.theses.fr/2001ECAP0728.
Cérin-Delaval, Oriane. "Development and characterization of a novel flame retardant EVM-based formulation : investigation and comprehension of the flame retardant mechanisms." Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL10132/document.
This study is dedicated to the formulation of an innovative flame retardant material based on elastomeric vulcanized ethylene-vinyl acetate copolymer (EVM) used in the fields of cable and transportation, and to the comprehension of the flame retardant phenomena. The screening of various additives, evaluated in EVM in terms of mechanical and fire retardant properties, allowed the determination of an innovative combination, made of aluminium trihydroxide (ATH) and aluminium diethyl phosphinate (OP1230). The ATH mode of action, generally assumed to be a cooling effect, was revisited by a kinetic approach of the thermal degradation of the EVM/ATH formulation in oxidative and pyrolytic conditions, associated with the investigation of the evolution of the material in simulated fire conditions. It was found that the cooling effect occurs, but the main protective effect of ATH consists in the formation during combustion of an alumina layer, diminishing the mass and heat transfer and thus the flame feeding. In the complete formulation (EVM/ATH/OP1230), the chemical interactions between ATH, OP1230 and the polymer were investigated, revealing that the synergistic effect provided by the two additives results from the creation during combustion of a resistant glassy layer. Moreover phosphorous species are evolved in the gas phase during combustion, acting as flame inhibitors
Beaugendre, Agnès. "Self-stratifying flame retardant coatings for plastics." Electronic Thesis or Diss., Lille 1, 2017. http://www.theses.fr/2017LIL10114.
This PhD work is a proof of concept on the design of flame retardant (FR) self-stratifying coatings for polycarbonate (PC). This one pot process allows an eco- and smart-development of new products while reducing cost, processing time and solvent emission. In this work, two original self-layering coatings based on epoxy /silicone and /fluoropolymer blends were developed. Their perfect stratification was evidenced using different techniques, in a thickness range up to 130 µm. The influence of solvents characteristics, hardener, curing conditions, fillers and their incorporation phase was studied. Finally, the system diluted in butylacetate: xylene (1:1) leads to the best layering and adhesion, with the thermoplastic phase located on the top of the film. The FR fillers tested (iron oxide, calcium carbonate and two phosphorus based additives) do not affect the layering when introduced up to 10 wt.%. However, visual appearance and adhesion are strongly dependent on the solvent used. The best improvements in terms of FR properties, adhesion and weatherability (temperature, UV, humidity) were obtained by adding micrometric Fe2O3 particles: it allows the formation of a protective barrier which limits substrate/flame mass transfers, and prevents from the yellowing of the system under UV. Although Fe2O3 catalyzes the thermal degradation of the fluorinated resin, the coating reduces flame spread, dripping and slightly promotes the formation of a char. When added to the silicone-based blend, the thermal stability is improved, which allows reducing the combustibility and ignitability of the coated PC. Finally, those properties are relatively maintained after 8 weeks of ageing
Beaugendre, Agnès. "Self-stratifying flame retardant coatings for plastics." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10114/document.
This PhD work is a proof of concept on the design of flame retardant (FR) self-stratifying coatings for polycarbonate (PC). This one pot process allows an eco- and smart-development of new products while reducing cost, processing time and solvent emission. In this work, two original self-layering coatings based on epoxy /silicone and /fluoropolymer blends were developed. Their perfect stratification was evidenced using different techniques, in a thickness range up to 130 µm. The influence of solvents characteristics, hardener, curing conditions, fillers and their incorporation phase was studied. Finally, the system diluted in butylacetate: xylene (1:1) leads to the best layering and adhesion, with the thermoplastic phase located on the top of the film. The FR fillers tested (iron oxide, calcium carbonate and two phosphorus based additives) do not affect the layering when introduced up to 10 wt.%. However, visual appearance and adhesion are strongly dependent on the solvent used. The best improvements in terms of FR properties, adhesion and weatherability (temperature, UV, humidity) were obtained by adding micrometric Fe2O3 particles: it allows the formation of a protective barrier which limits substrate/flame mass transfers, and prevents from the yellowing of the system under UV. Although Fe2O3 catalyzes the thermal degradation of the fluorinated resin, the coating reduces flame spread, dripping and slightly promotes the formation of a char. When added to the silicone-based blend, the thermal stability is improved, which allows reducing the combustibility and ignitability of the coated PC. Finally, those properties are relatively maintained after 8 weeks of ageing
Dupretz, Renaud. "Synthesis of novel phosphinate flame retardants for poly butylene(terephthalate) (PBT) and polyamide 6 (PA6)." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10193/document.
This study deals with the flame retardancy of two engineering plastics, the poly(butylene terephthalate) (PBT) and the polyamide 6 (PA6), widely used in the electrical and electronic equipment (EEE). The focus is made on the incorporation of phosphorus- and nitrogen-containing flame retardant (FR) additives. The main goal of this project was to prepare novel FR through organic synthesis. Five aluminum phosphinates were prepared by reaction of amines on hydroxyphenylphosphnyl propanoic acid and an aluminum promoter. The salts were incorporated to PBT and PA6, with or without co-additives, and the materials were tested in the UL-94, test investigating the vertical propagation of the flame and widely used in the EEE industry. Among the five salts, only the aluminum salt of phenyl amide of hydroxyphenylphosphnyl propanoic acid showed outstanding properties as FR. Other tests were carried out, among which an instrumentation of the UL-94 test, to build a way to the comprehension of mechanisms. First observations were completed by various microanalyses. It has been shown that the decomposition of PAS enhances that of PBT in parallel to its cooling. The liberation of phosphorus-containing species in the gas-phase, despite les efficient than in the case of other commercial FR, gives the formulation its auto-extinguishing character
Dilger, Melvin. "Flame retardant expanded polypropylene for applications in electric vehicles : design and mechanism of action." Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILR066.
Today the sector of transport is changing with the transition from thermal vehicles to electrical vehicles. Thus, the materials widely used in vehicles as EPP also have to change due to higher requirements in terms of fire properties.In this thesis, three approaches were considered to increase the fire properties of EPP and reach a V0 rating at UL-94 vertical test, according to the three steps of manufacturing EPP. In fact, to manufacture EPP, three steps are necessary: (1) the polypropylene (PP) is melt blended with various additives via an extrusion process, (2) the blended PP is expanded, i.e. an expansion gas is introduced into it to form EPP beads and (3) the EPP beads are then molded into the desired shape. Before investigating the different approaches, the UL-94 vertical test was instrumented in order to obtain more information and have a better understanding in terms of fire properties. The different approaches considered were: (1) incorporating flame retardants and synergists into the PP matrix before expansion, this is the most common approach. This approach was deeply investigated with a comparison between several FRs with different modes of action (intumescent FR, free radical generator, etc), an optimization of the most efficient FRs combination and a study of the influence of industrial manufacturing, especially the expansion step. Indeed, the FRs can disrupt the foaming processability (expansion step), due to the high amount of FRs needed and the fact that FRs can play the role of nucleating agents. Moreover, the mechanism of action of the chosen FRs was studied before and after the expansion step. To counter the complexity of the expansion step in the approach (1), alternative approaches were studied in order to validate others concept. The alternative (2), applying a flame-retardant coating on the EPP beads (before molding) and (3) applying a flame-retardant coating to the molded final piece (EPP bars). However, these approaches have also some drawbacks. Indeed, the EPP has poor adhesion properties because it has no functional groups. Thus, an optimization of a plasma treatment was needed in order to increase the adhesion of EPP. Several flame retardant coatings were applied on the surface and the moldability of the coated EPP beads was studied. Finally, the fire properties at UL-94 vertical test of the molded coated EPP beads and coated EPP bars were studied
Hoffendahl, Carmen. "Flame retardancy of EVM-based polymers with low smoke emission." Electronic Thesis or Diss., Lille 1, 2014. http://www.theses.fr/2014LIL10048.
This work deals with new elastomeric ethylene-vinyl acetate (EVM) materials containing aluminum trihydroxide (ATH) in combination with melamine or its derivatives are evaluated regarding mechanical properties, hydrothermal aging, fire retardancy and smoke release. The decomposition mechanism of EVM containing ATH and melamine borate (MB) (EVM-ATH-MB) is analyzed in details because of its high stability during hydrothermal aging and its low smoke release. Decomposition reactions EVM-ATH-MB are studies using amongst others new approaches such as pyrolysis-gas chromatography-mass spectrometry (py-GCMS) and mass loss calorimeter coupled with Fourier transform infra-red (MLC-FTIR). It is found that EVM-ATH-MB is mainly protected by the mode of action of ATH diluting the fuel and forming a protective layer that reduces mass and heat transfer
Hoffendahl, Carmen. "Flame retardancy of EVM-based polymers with low smoke emission." Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10048/document.
This work deals with new elastomeric ethylene-vinyl acetate (EVM) materials containing aluminum trihydroxide (ATH) in combination with melamine or its derivatives are evaluated regarding mechanical properties, hydrothermal aging, fire retardancy and smoke release. The decomposition mechanism of EVM containing ATH and melamine borate (MB) (EVM-ATH-MB) is analyzed in details because of its high stability during hydrothermal aging and its low smoke release. Decomposition reactions EVM-ATH-MB are studies using amongst others new approaches such as pyrolysis-gas chromatography-mass spectrometry (py-GCMS) and mass loss calorimeter coupled with Fourier transform infra-red (MLC-FTIR). It is found that EVM-ATH-MB is mainly protected by the mode of action of ATH diluting the fuel and forming a protective layer that reduces mass and heat transfer
Hébert, Damien. "Etude de la combustion des matériaux solides, application à la sécurité incendie." Phd thesis, INSA de Rouen, 2012. http://tel.archives-ouvertes.fr/tel-00795236.
Prieur, Benjamin. "Modified lignin as flame retardant for polymeric materials." Thesis, Lille 1, 2016. http://www.theses.fr/2016LIL10083/document.
The aim of this PhD is to contribute to the valorization of lignin, an abundant byproduct of pulping industry by using it as flame retardant (FR) additive for polymeric materials. First, phosphorylation of lignin was undertaken. According to structural characterization, phosphorus was found to be covalently bonded to lignin. As a consequence, the thermal stability of lignin was enhanced as well as the char yield. Based on these results, both neat and phosphorylated lignin were incorporated in several polymers in order to assess their FR performance and the influence of phosphorus. Promising results were especially obtained in polylactic acid (PLA) and acrylonitrile-butadiene-styrene (ABS). Then FR performance of formulations combining lignins and other additives was discussed. A large screening using lignin as FR additive in PLA and ABS was therefore achieved. The system considering phosphorylated lignin in ABS was finally investigated in detail. FR performance as well as thermal degradation were deeply studied. Lignin produces a char when exposed to a flame or a heat source which acts as a physical layer by mainly limiting mass transfers between the burning polymer and the flame. The char produced by phosphorylated lignin demonstrated a higher efficiency, thus leading to enhanced FR properties. Phosphorus was indeed active in the condensed phase, promoting the char formation and leading to structures which stabilize the char. The mode of action of lignin and phosphorylated lignin as flame retardant additive in ABS was elucidated
Coquelle, Mathieu. "Flame retardancy of polyamide 6 fibers : the use of sulfamate salts." Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10219/document.
The aim of this Ph.D. work is the fire retardancy of polyamide 6 (PA6) fibers. Among the different techniques used to modify a synthetic fiber or fabric, the incorporation of fire retardants (FR) directly in the melt during extrusion was chosen. Processing temperatures of PA6 being rather high (generally > 250 °C), a rigorous selection of phosphorus and sulfur based FR was done. Moreover, FR must be stable at the processing temperature, while being spinnable and efficient at low loadings (<10 wt.-%). Sulfamate salts such as ammonium and guanidine sulfamate (AS and GAS) were found efficient and the PA6 formulations were spinnable. The modes of action were investigated through a study of the condensed and gas phase. However, when scaling up the process from microextruder to a large-scale extruder, processing issues were observed. In order to overcome this problem, the use of a co-additive (melamine polyphosphate), offering a synergistic effect with sulfamate salts, allowed to decrease the amount of GAS in the PA6 formulation while enhancing the FR performance. Thus, large-scale extrusion of the FR PA6 was performed successfully
Muller, Maryska. "Systemic approach of the synergism in flame retarded intumescent polyurethanes." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10109/document.
The purpose of this Ph.D work is to present and to understand the synergy observed in the fire performances of intumescent polyurethane (PU) formulations by the addition of nanoparticles (NP). Indeed, it was shown that the addition of ammonium polyphosphate (APP) in PU leads to interesting fire properties that can be enhanced substituting a small amount of APP by NPs (MgO, SiO2, octamethyl polyhedral oligomeric silsesquioxanes (OMPOSS) and gold). The nature and content of the NPs play an important role on the fire retardant properties and mechanisms. First, a thermal stabilization was observed between APP and the different NPs except OMPOSS. The synergy mechanism was thus attributed to a condensed phase action where a range of chemical species, characterized by solid state NMR, are created upon heating the material in different conditions. The char properties, such as thermal conductivity, expansion and morphology, were then characterized using novel techniques (in particular tomography). It was shown that they are linked with the thermal barrier effect of the residual material explaining the good fire properties obtained when combining APP and NPs. The mechanical strength of chars developed in different conditions was also investigated but do not play a significant role on the synergy mechanism
Moussou, Julien. "Caractérisation expérimentale du flux thermique transitoire pariétal pour différents modes de combustion." Thesis, Chasseneuil-du-Poitou, Ecole nationale supérieure de mécanique et d'aérotechnique, 2019. http://www.theses.fr/2019ESMA0010/document.
CO2 emissions in internal combustion engines are linked with inefficiencies due to wall heat losses during combustion.Those losses exhibit a sharp peak of a few MW/m2 close to top dead center and are linked to complex flame/wall interaction phenomena that vary with the combustion mode. A fine understanding of the associated phenomena requires experimental characterization of wall heat flux with a time resolution better than the millisecond. In this PhD work, a rapid compression machine and a precombustion cell are used to reproduce engine combustion phenomena. Thin-junction thermocouples allow an instantaneous measurement of the wall heat flux with a time resolution of 0.1 ms. Three combustion modes are generated: propagation flame, diffusion flame and auto-ignition.Different possible measurement technologies and procedures (thermocouples, thermoresistances and rapid phosphor thermometry) are compared and benchmarked against the features of combustion phenomena. Flux during wall heat transfer reaches values of a few MW/m2 and its shape varies with the combustion mode. During premixed flame propagation, flux is dominated by a peak during flame-wall interaction of about 5 MW/m2 in amplitude and 0.5 ms in duration. During Diesel combustion, heat flux is approximately constant during the injection duration; itsevolution is driven by an increase of the convection coefficient up to 10 kW/m2/K, which is attributed to air entrainment by the spray; the temperature increase from combustion is considered a second-order effect. During combustion presenting a pressure wave propagation (e.g. knock for some spark-ignition cases or HCCI with high energy content), the intensity of pressure oscillations and wall heat flux are shown to be correlated. That correlation is independent of the phenomenon creating the pressure wave; heat flux during knock is 3-5 times higher than for a comparable premixed propagation flame
Escaich, Alain. "Une description améliorée de la combustion turbulente dans les flammes de charbon pulverisé." Rouen, 2000. http://www.theses.fr/2000ROUES040.
Drissi, Mohamed. "Un modèle de propagation de feux de végétation à grande échelle." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4704.
The present work is devoted to the development of a hybrid model for predicting the rate of spread of wildland fires at a large scale, taking into account the local heterogeneities related to vegetation, topography, and meteorological conditions. Some methods for generating amorphous network, representative of real vegetation landscapes, are proposed. Mechanisms of heat transfer from the flame front to the virgin fuel are modeled: radiative preheating from the flame and embers, convective preheating from hot gases, radiative heat losses and piloted ignition of the receptive vegetation item. Flame radiation is calculated by combining the solid flame model with the Monte Carlo method and by taking into account its attenuation by the atmospheric layer between the flame and the receptive vegetation. The model is applied to simple configurations where the fire spreads on a flat or inclined terrain, with or without a constant wind. Model results are in good agreement with literature data. A sensitivity study is conducted to identify the most influential parameters of the model. Eventually, the model is validated by comparing predicted fire patterns with those obtained from a prescribed burning in Australia and from a historical fire that occurred in Corsica in 2009, showing a very good agreement in terms of fire patterns, rate of spread, and burned area
Matar, Mohamad. "Exploration de nouvelles voies pour l'ignifugation des polymères." Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0067/document.
In this study, we have tried to develop new formulations to improve the thermal stability and fire behavior of three polymer matrices widely used: the polyethylene (PE), the polystyrene (PS) and the polyamide 66 (PA 66). The intumescent system used consists to combine a classical flame retardants (ammonium polyphosphate (APP) and pentaeryhthritol (PER)) with a small amount of nanooxides whose properties can be adjusted in order to improve the compatibility of the melting mixture, or to change the degradation mechanism by a chemical (catalytic effect) or physical (insulating layer, viscosity, etc …) process. The total amount of additives has been set at 25wt%. An important part of this study was consecrated to the synthesis of oxides with different morphologies, porosities, structures and functionalities. In this regard, the mesoporous silica has an advantage of having a high surface area (700-1400 m²/g) and a pore size compatible with the polymer chains. By adapting the synthesis conditions, we have aimed to correlate between some parameters related to the prepared silicas (such as (1) the specific surface area (2) particle size (3) pore size (4) morphology and (5) the type of structure (usually SBA-15)) on the thermal stability and fire behavior of different polymer matrices. A comprehensive study has been conducted globally, regardless of the matrix, that the improvements provided by the mesostructured silicas are modest compared to those elicited by classical FR. However, the fire behavior has been improved (particularly LOI) by combining APP/PER system with 1-2wt% of SBA-15. The surface modification of SBA-15 by grafting a different organic functions (CTAB, amine, thiol, phenol, phosphonate, benzoic acid and diphenylphosphate), inorganic species (aluminum, phosphoric acid and tungstophosphoric acid) or metals (copper, nickel) have been the subject of an advanced characterizations in order to assess the amount and the thermal stability of the grafted species, well as the nature of the surface bonds. Other types of synthetic nanooxides (aluminophosphates, zirconium phosphate and titanate nanotubes) or commercial (CeO2, ZrO2, CeZr and CePr) have been also studied. Most of these particles in combination with APP/PER system have shown a slightly positive effect on the thermal stability and fire behavior of polymers. In mechanistic terms, the nanooxides have mainly an effect on enhancing the barrier effect. The analyses carried out by Py/GC/MS showed that the grafted oxides by acidic species catalyze the conversion of alkenes and dienes (resulting from the decomposition of PE) to aromatics. In the presence of SBA-15, the analysis of char (by XRD and FTIR) shows the formation of new crystalline phases which enhance the protective layer
Vahabi, Henri. "Combinaison de nanoparticules et de composés phosphonés pour améliorer le comportement au feu du PMMA." Thesis, Montpellier 2, 2011. http://www.biu-montpellier.fr/florabium/jsp/nnt.jsp?nnt=2011MON20095.
Poly(methylmethacrylate) (PMMA) is an important thermoplastic, widely used in industry. Unfortunately, it is a highly flammable polymer. The aim of this research was to improve the thermal stability and fire behavior of PMMA. First, we studied the influence of the dispersion of pure or treated kaolin on the fire behavior and thermal stability of PMMA. In second part of this work, the chemical modification of PMMA, using copolymerization of methyl methacrylate (MMA) with two phosphonated co-monomers was studied. Finally, we interested in chemical or physical incorporation of two types of polyhedral oligomeric silsesquioxane particles (POSS) in the PMMA or modified PMMA copolymère (MMA – co- monophosphonated monomer)). The effect of the combination of POSS particles and modified PMMA on the thermal degradation and flammability of PMMA was studied. In our work, the effect of phosphorus in the gas and condensed phase was separately studied. This study allowed us to define an efficiency index of phosphorus in each phase
Louisy, Jérémie. "Synthesis of novel phosphinate salts and development of formulations for the flame retardancy of glass fiber reinforced PolyButylene Terephthalate (PBT)." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10162/document.
This study deals with the formulation of an innovative flame retardant material based on glass fiber reinforced PolyButylene Terephthalate (PBT/GF) used in Electronic and Electrical Equipments (EEE). In a first approach, the flame retardant properties of various additives in combination with the commercial aluminium diethylphosphinate are evaluated in PBT/GF. In a second approach, a variety of phosphinate salts derived from carboxyethyl(methyl)phosphinic acids are synthesized and then tested alone or in combination with FR additives. Two innovative flame retardant systems, namely the combination of Resorcinol bis-Diphenyl Phosphate (RDP) modified bentonite clay with either the aluminium diethylphosphinate or the aluminium phenyl amide of carboxyethyl(methyl)phosphinate, were found to greatly improve the fire behavior of PBT/GF. The FR mechanism of flame retardants were investigated and compared. Both phosphinate salts from the innovative systems mainly act through a gas phase mode of action by releasing phosphinic acids. Regarding the commercial product, the release of phosphinic acid occurs due to chemical interaction between the phosphinate salt and the PBT matrix while the synthesized product only moderately interacts with the polymer
Gallou, Hélène. "Amélioration du comportement au feu du polyamide 6,6 par traitement de surface et en masse." Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL10186/document.
The main objective of this study concerns the development of fire retardant PA66 formulations, reinforced or not with glass fibers, uses for electrical material. The experimental approaches studies the influence of non-halogenous organophosphorous flame retardant, such as melamine polyphosphate, phosphinate, or melamine cyanurate on the fire performance of the PA66 in order to understand the fireproofing mechanisms. The efficiency in terms of fire protection defines the OP1230 as optimal flame retardant. The attention was related more particularly to the formulation with the minimal amount of additive so that the product present to the fire conditions for electric applications. The thermal degradation study shows that no new species are identified during the degradation which indicates that no chemical reaction appears. This means that only physical interactions could explain the improved fire behavior of the heated formulation. The evolution of the intermediate structures has been investigated and mechanisms have been proposed according to the conclusions made. The second axis of the study concerns the use of surface treatments to fireproof the polymer surface. Thin layer deposits using cold plasma assisted polymerization technique or thicker layer by intumescent coating applications were carried out on the PA66-25 % FV after surface activation. Both processes allows to preserve the mechanical and physical properties of the polymer. The last step of the work was to apply the surface treatment on PA66 containing 5 % OP1230 which gives very satisfying results in terms of fire protection, the OP1230 showed the best efficiency in terms of fire protection
Coudour, Bruno. "Influence de la végétation et du relief dans les feux de forêt extrêmes : étude de l'accumulation, de la dégradation et des propriétés de combustion des composés organiques volatiles issus des feux de forêt." Thesis, Poitiers, 2015. http://www.theses.fr/2015POIT2290/document.
Mediterranean firefighters cope with powerful accelerations of forest fires (AFF) whose mechanisms are not very well understood. Vegetation is the only fuel of forest fire, then we studied the gases coming from them. First, we studied the thermal degradation of four Biogenic Volatil Organic Compounds (BVOCs) thanks to a flash pyrolysis and a tubular oven. From this study and literature, we chose a representative VOC mixture to study its combustion properties. We determined Minimal Ignition Energy (MIE) and its laminar burning speed of mixtures of α-pinene/benzene that are respectively the main VOC detected in vegetation and forest fire smoke. The last chapter experiment the steady-state gas accumulation above a 1/400 V-shaped forest model
Almirón, Baca Jonathan Joseph. "Etude des propriétés thermo mécaniques des matériaux polymères avec addition du résidu solide de pyrolyses." Electronic Thesis or Diss., Université de Lille (2022-....), 2022. http://www.theses.fr/2022ULILR039.
The final disposal of vehicles at their end-of-life is generating a world environmental problem. Nowadays, in Europe there are companies dedicated to the disassembly and recovery of the components that can be reused, being plastic wastes among these components. Thus, in the first part of this research, it was proposed to treat these plastic wastes through a pyrolytic process in order to transform them into solid wastes, to be used as part of the additives in a flame retardant system for a polypropylene matrix. Vehicle residues were segregated according to their densities and characterized. They were subsequently incorporated into a thermal pyrolysis process giving, as a result, a solid pyrolytic residue (RSP). Using the RSP, the polymer blends were prepared composed of polypropylene, ammonium polyphosphate and pentaerythritol. Their thermal, mechanical and flammability properties were evaluated by thermogravimetric analysis, modulus of elasticity, tensile strength, percentage of deformation and the limiting oxygen index.In the second part of this research, it was determined and compared whether the heat treated solid waste from the pyrolysis of plastic waste of vehicles (RS-T), volcanic ash (CV) and rice husk ash (CR) have any synergistic action when added to polypropylene flame retardant additives (such as ammonium polyphosphate and pentaerythritol). These materials were characterized by nitrogen adsorption analysis (Brunauer-Emmett-Teller method), X-ray fluorescence and X-ray diffraction. The abundant presence of SiO2 and Al2O3 was determined, which are considered flame-retardant minerals. Polymer matrix composites were synthetized, which were composed of polypropylene, ammonium polyphosphate, pentaerythritol and CV, CR and RS-T materials (at 1% to 9% by wt.). The thermal stability and fire resistance of the synthesized polymer mixtures were evaluated through the limiting oxygen index, thermogravimetric analysis and cone calorimetry. It was determined that these materials have a synergistic action with flame-retardant additives as an increase in their fire resistance has been demonstrated.In the final part of this research, the influence of natural zeolites obtained from ashes of the Ubinas volcano, as synergistic agents in a flame-retardant system, has been studied. Four different zeolites were synthesized from volcanic ash, including calcined and not calcined ashes, being placed in an alkaline solution at three synthesis temperatures. Zeolites were characterized by X-ray diffraction, nitrogen adsorption analysis (Brunauer-Emmett-Teller method) and scanning electron microscopy. Polypropylene polymer blends were prepared with ammonium polyphosphate, pentaerythritol and the zeolites at 1, 5 and 9% (by wt.). Their thermal stability and fire resistance were evaluated by thermogravimetric analysis, limiting oxygen index, ULV-94 vertical flammability test and cone calorimetry. Their morphological structure was tested by scanning electron microscopy. It was determined that the synthesis temperature and the use of calcined and non-calcined volcanic ashes has an influence on the characteristics of zeolites and on their synergistic action with flame retardants and therefore, on their flame-retardant properties