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Highlights: [•] We investigate the fire protection of intumescent silicone based coatings. [•] The effect of the organometallic catalyst used is detailed. [•] The titanium based catalyst increases the fire performance of the coating. [ABSTRACT FROM AUTHOR]

Abstract: Polyamide 6,6 (PA6,6) is usually fire retarded in bulk, using aluminum diethylphosphinate (AlPi). In one of our recent papers, it was shown that good fire-retardant properties (e.g. V0 at the UL94 test) could also be achieved by applying an intumescent varnish on the PA6,6 surface. Excellent fire-retardant properties were even obtained combining 5% of AlPi in the bulk with an intumescent coating applied on the polymer surface. The Glow Wire Flammability Index (GWFI) test was validated at 960 °C whereas it was only validated at 750 °C without the AlPi. This paper first aims to describe the mechanism of action of an intumescent coating to protect a polymer, as it was never previously studied in the literature. It was evidenced, analyzing with 13C, 31P and 27Al solid state NMR spectra of the materials at different combustion times that during burning one part of the virgin polymer begins to degrade and is mixed with the semi-viscous charring intumescent layer. In some way, due to this mixture of both phases, it is as if the polymer was fire retarded in bulk during burning. The second objective was to investigate the potential synergy between the gas phase fire-retardant mechanism of AlPi and the condensed phase fire protective mechanism of the intumescent coating to explain the enhanced fire-retardant properties. Similarly, using NMR technique, the interest to combine the bulk treatment in low amount and the intumescent coating was evidenced: the AlPi cannot completely sublimate because of the protective coating, and is probably condensed inside the intumescent structure pores. As it is trapped in the condensed phase, it then degrades into aluminophosphates, increasing the heat barrier efficiency of the expanded char layer. [Copyright &y& Elsevier]

Abstract: The fire performance of curable-silicone based coatings containing expandable graphite (EG) is evaluated in hydrocarbon fire scenario (standard UL1709) using a lab-scale furnace test. From 5% to 25% of expandable graphite is incorporated in the silicone matrix to make the coating swell during the fire experiment. Fire performance of 25%EG/silicone-based coating is better than that of commercial intumescent paint used as reference. This is explained by a high swelling velocity (18%/s), a high expansion (3400%), an impressive cohesion of the char and a low heat conductivity at high temperature (0.35 W/K m at 500 °C). To elucidate this way of charring, the residue after fire testing was analyzed by scanning electron microscopy, transmission electron microscopy, energy dispersive spectrometry, X-ray photoelectron spectroscopy and X-ray diffraction. It is shown that the char is composed of two main parts: the top is composed of quartz and amorphous silica which coat graphite flakes and the heart of the char is composed of graphite flakes embedded in degraded silicone forming a complex structure. It is shown that, the good cohesion of the char is due to: (i) the presence of the undegraded silicone matrix; and (ii) the coating of graphite pellets by silicone. [Copyright &y& Elsevier]

Abstract: Fire retarded poly(ethylene terephthalate) (PET) has been obtained by the incorporation of octamethyl polyhedral oligomeric silsesquioxane (OMPOSS) and Exolit OP950, a phosphinate-based compound, in recycled PET. The presence of Exolit OP950 only leads to intumescence explaining the improvement of the flame retardancy. The addition of OMPOSS leads to a synergistic effect considerably increasing the fire retarding performances of the polymer in terms of cone calorimetry and limiting oxygen index even if a small thermal stabilisation as well as a very poor dispersion of OMPOSS and OP950 into the matrix has been observed. [Copyright &y& Elsevier]

Abstract: The aim of this work is to better understand the role and the mechanism of action of boric acid and of coated ammonium polyphosphate (pure ammonium polyphosphate coated with THEIC) used as flame retardants in a commercial intumescent epoxy-based formulation using analytical techniques including thermogravimetric analyses (TGA) and solid-state NMR. In a previous paper, we detected that some reactions took place during the intumescence phenomenon between boric acid and ammonium polyphosphate upon heating. The paper focuses on the analysis of the degradation of those sole components and on the study of their interaction. It is first shown that the THEIC increases the thermal degradation rate of ammonium polyphosphate. This enables the degradation products of boric acid and coated ammonium polyphosphate to react together, resulting in the formation of borophosphate. It is suggested that the formation of this product provides the superior mechanical resistance of the char and promotes the adhesion of char on the steel plate. [Copyright &y& Elsevier]

Abstract: This study investigates the role of the binder in the efficiency of intumescent coatings. It is generally known that an acid source, a carbon source and a blowing agent are the main ingredients of such paints. However, since the binder may react with these ingredients, it may significantly affect the intumescence process. To begin with, the effect of the nature of the monomers, which compose the binder, on the chemical reactivity between the binder and the intumescent additives is investigated using thermogravimetric analysis. It is found that the thermal stability is enhanced when the copolymer is prepared with substituted styrene. Subsequently, the effect of the binder is investigated from a physical aspect. Special attention is devoted to the expansion rate and the dynamic viscosity. Finally, the efficiency of protective behaviour of the intumescent coatings prepared with the copolymers is evaluated. It is found that the thermal insulation is greatly improved when using a mixture of linear and crosslinked copolymers as the binder in intumescent coatings particularly when these copolymers are prepared from monomers showing good reactivity with ammonium polyphosphate. [Copyright &y& Elsevier]

This study deals with the fire retardant performance of vinyl acetate (VA)/butyl acrylate (BA) copolymers using phosphorus compounds as additive or as co-monomer. First, VA/BA copolymer has been mixed with phosphorus additives from various sources: red phosphorus, organo-phosphates, organo-phosphonate, inorganic phosphate and an intumescent system (ammonium polyphosphate and pentaerythritol). The incorporation of 5 wt.-% phosphorus leads to VA/BA copolymers with improved fire properties whatever the source of phosphorus used. The best performance is achieved with the intumescent system. Second, VA and BA monomers have been copolymerised with phosphorus monomers (phosphate and phosphonate). Both systems present fire retardancy of interest. The better performance is achieved using phosphonate. Both systems are assumed to work in the condensed phase. [Copyright &y& Elsevier]

This study investigates the role of the binder in an intumescent paint. In fact, it is generally known that acid source, carbon source and blowing agent are the main ingredients of such a paint. However, since the binder may react with these ingredients, it is also a very important component of an intumescent paint. To begin with, the effect of the nature of the monomers composing the polymeric binder, on the chemical reactivity between the binder and the intumescent additives is investigated using thermogravimetric analysis, solid state NMR and FTIR analysis. It is found that the thermal stability increases when the copolymer is based on substituted styrene. Subsequently, the efficiency of protective behaviour of the intumescent coatings is evaluated varying the nature of the binder resin. It is found that the thermal insulation is greatly improved when using a mixture of a linear copolymer presenting a good reactivity with the acid source and a cross-linked copolymer as binder in the intumescent paint. [Copyright &y& Elsevier]

This work deals with the mechanism of degradation of vinyl acetate/butyl acrylate (VA/BA) copolymers varying the VA/BA ratio. It is shown that for higher VA contents, the degradation starts at comparatively lower temperature but a more thermally stable material is formed. The mechanism of degradation of VA/BA copolymers is then compared with PVA and PBA homopolymers. It appears that the fractions of degradation (gases, high boiling products and residue) for VA/BA copolymer is a combination of those of polyvinyl acetate (PVA) and polybutyl acrylate (PBA). However, a slight stabilisation occurs when VA/BA are co-polymerised together compared with a VA and BA combination. Moreover, the comparison of the thermo-oxidative degradation with the pyrolysis demonstrates that the mechanisms are similar at least up to 450 °C. [Copyright &y& Elsevier]

Bioaccumulation of Cd, Pb, Cu and Zn in the Antarctic gammaridean amphipod Paramoera walkeri (Stebbing, 1906) was investigated at Casey station (Australian Antarctic Territory). The main goals were to provide information on accumulation strategies of the organisms tested and to verify toxicokinetic models as a predictive tool. The organisms accumulated metals upon exposure and it was possible to estimate significant model parameters of two-compartment and hyperbolic models. These models were successfully verified in a second toxicokinetic study. However, the application of hyperbolic models appears to be more promising as a predictive tool for metals in amphipods compared to compartment models, which have failed to adequately predict metal accumulation in experiments with increasing external exposures in previous studies. The following kinetic bioconcentration factors (BCFs) for the theoretical equilibrium were determined: 150–630 (Cd), 1600–7000 (Pb), 1700–3800 (Cu) and 670–2400 (Zn). We find decreasing BCFs with increasing external metal dosing but similar results for treatments with and without natural UV radiation and for the combined effect of different exposure regimes (single versus multiple metal exposure) and/or the amphipod collective involved (Beall versus Denison Island). A tentative estimation showed the following sequence of sensitivity of P. walkeri to an increase of soluble metal exposure: 0.2–3.0 μg Cd l−1, 0.12–0.25 μg Pb l−1, 0.9–3.0 μg Cu l−1 and 9–26 μg Zn l−1. Thus, the amphipod investigated proved to be more sensitive as biomonitor compared to gammarids from German coastal waters (with the exception of Cd) and to copepods from the Weddell Sea inferred from literature data. [Copyright &y& Elsevier]

In this study, the effect of several parameters (nature of clay and clay loading) on the fire retardancy of the nanocomposite is investigated. It is observed that the nature of the cations, which compensates the negative charge of the silicate layers, affects the fire performance even though they are improved for both investigated montmorillonite-type fillers. The clay loading also affects the fire properties. In a second part, the materials are characterized using thermogravimetric analysis and small-angle X-ray diffraction in order to better understand the obtained fire retardant performance. It is observed that the degree of dispersion determined by X-ray diffraction can be correlated with the fire performance of the polymer clay composite. [Copyright &y& Elsevier]

The present work is dedicated to the development of a new method, which enables a better understanding of the intumescence process. Many studies have investigated char formation from a chemical aspect but the foaming and strength of the char have not been well studied before. Thermal scanning measurements using a rheometer as a fire reactor enable a correlation between the fire behaviour and thermal behaviour and the visco-elastic properties of the material. This study investigates the rheological modifications of polyurethane thermoset coatings with or without fire-retardant. The rheological and mechanical destruction properties of the protective char layer have been correlated with their fire retardant performance for two additives: ammonium polyphosphate and expandable graphite. In a first part, the expansion of pure PU and of intumescent materials under normal force is studied. Then, the visco-elastic behaviour is investigated in order to evaluate the different steps of the intumescent process (development, stability and destruction). Finally, mechanical properties of the intumescent chars are discussed. [Copyright &y& Elsevier]

This work reports the chemical changes of an intumescent flame retardant ethylene vinyl acetate (EVA)-based material during combustion. Ammonium polyphosphate and polyamide-6 have been used as the acid source and the carbonisation agent respectively in the additive system. The main characteristic steps of the combustion were first determined using a cone calorimeter. The process of combustion was decomposed into several steps: heating before ignition, ignition, protection by a charred layer, destruction of the protective character of the carbonaceous shield, formation of a stable residue. At each step, the samples were removed from the cone calorimeter and analysed using X-ray photoelectron spectroscopy (XPS). It gives evidence of the presence of nitrogen atoms bonded to carbon in the protective shield. The effect of water rinsing of the obtained charred residue was also investigated. [Copyright &y& Elsevier]

Abstract: The morphology of carbonized materials resulting from an intumescence phenomenon was studied. The investigated material is a polyurethane matrix filled either by 30 wt.-% of ammonium polyphosphate or by a combination of 28 wt.-% of ammonium polyphosphate and 2 wt.-% of nano-magnesium oxide. These fillers were incorporated in the polyurethane directly during the synthesis step. The carbonized materials or char, are obtained in a specific fire scenario. Characterization of their morphology is carried out using X-ray computed tomography. The heat conductivity of the systems is additionally measured as a function of temperature in order to correlate structure and properties of the intumescent residues. The formation of different char structures with incorporation of magnesium oxide (in particular formation of bubbles of different size) is first evidenced. These observations are consistent with the heat conductivity data. Tomography images demonstrate that the intumescence process is a dynamic process since non degraded polymer is left at the beginning of the fire test, which is not the case for longer time. The dispersion of fillers has finally been investigated in the chars and it is evidenced different steps of intumescence's development in the material. [Copyright &y& Elsevier]

Abstract: In this work, we have investigated the intumescent behaviour of linear low-density polyethylene (LLDPE) containing calcium carbonate (chalk) treated by stearic acid. This system swells during burning and creates a protective layer when exposed to an external heat flux of 50kW/m2 in a mass loss calorimeter. This system has been fully characterized by FTIR, XRD, TGA and SEM. The carbonation/decarbonation temperatures, the swelling phenomenon and the effect of the thermal stress on the swelling have been examined. The residue is composed of a smooth surface made of chalk and CaO and a bulk of only chalk. Stearic acid allows a good dispersion of chalk particles into the LLDPE matrix, and contributes to form a cohesive network during burning when the thermal stress is high enough. A governing parameter of the intumescent effect is the particle size, which permits the formation of an insulating and cohesive mineral network during burning. [Copyright &y& Elsevier]

Abstract: Due to their complex composition and properties, the continuous thermal processing of solid–liquid mixtures (e.g. suspension of fragile particle in viscous carrier fluids) remains an empirical and random operation as compared to canning. Alternative technologies (e.g. ohmic heating) may achieve high-temperature treatment in a short time (HTST) but requires a perfect knowledge of thermo-physical and electrical properties of both particles and carrier fluid. Food properties are needed and play a significant role to predict and define the quality and behaviour of solid–liquid mixture. The properties of red beans (Phaseolus vulgaris L.) and a model non-Newtonian carrier fluid were studied throughout the duration of the process. Physical (rheological behaviour, density, shape and dimensions), mechanical (elasticity modulus, maximal deformation and stress) and thermal (heat capacity, thermal conductivity, thermal diffusivity) properties as a function of water content ranging from 11.6 to 67.4% w/w are reported. The electrical conductivity (electrical properties) was described as a function of the temperature and the solid concentration by a semi-empirical equation. The limiting factors to succeed a HTST for heterogeneous products in continuous thermal process were identified and discussed in the light of the properties of the foods involved. The large dispersion of particle mass volume had a simultaneous incidence of the suspension flow and the heat transfer. The volume expansion of particle (+22% between blanched and cooked bean) and the important loss of mechanical properties (−68% for elastic properties) constitutes unavoidable limiting factors inducing mechanical degradation and sometimes plugging of the duct. The electrical conductivity is strongly affected by a combined effect of temperature and solid concentration, which will induces irreversible heat treatment heterogeneity between particles. This work stresses that the continuous conventional or ohmic heating of these cooked dishes will be hard to achieve on an industrial scale. [Copyright &y& Elsevier]

Abstract: The thermal behaviour of a mixture containing an ammonium polyphosphate based compound (AP760) and zinc borate (ZB) is investigated. After an investigation of the degradation of the pure components, the interactions between them are examined by thermogravimetry. Then, X-ray diffraction (XRD) and 11B and 31P solid-state nuclear magnetic resonance (NMR) measurements have been carried out on residues of mixtures of AP760 and FBZB heat treated at different characteristic temperatures. It reveals the nature of the interactions taking place between the two components. It is demonstrated that reactions lead to the formation of zinc phosphate and of borophosphates. Mechanisms of thermal degradation are proposed. [Copyright &y& Elsevier]

Abstract: The influence of an intumescent back coating, applied to a cotton/PESFR (Trevira CS®) fabric, on thermal and fire behaviour system is investigated. The intumescent system is made of an acrylic binder resin and ammonium polyphosphate (APP). Thermal and fire behaviours are analysed. The pure acrylic binder resin coated on fabric leads to a decrease in the thermal and fire properties of the virgin materials. When APP is added to the binder resin, the decrease in the properties due to the handling treatment is limited. [Copyright &y& Elsevier]

This paper aims at developing an innovative approach to characterize the char residue of an intumescent coating obtained after a UL1709 furnace test. The intumescent formulation is based on an epoxy resin and contains numerous additives including zinc borate, ammonium polyphosphate and silicate fibers. The purpose is to characterize the numerous reactions that can occur upon burning using crossed methods including Electron Probe Micro-Analysis (EPMA), X-ray diffraction (XRD) and 1D/2D solid state Nuclear Magnetic Resonance (NMR). In particular, it emphasizes the potential of the advanced NMR technique namely two-dimensional Dipolar Heteronuclear Multiple Quantum Correlation (2D D-HMQC) NMR. As a result, EPMA evidenced that B/P and B/Si are located in the same domain suggesting the formation of boron-phosphorus and/or boron-silicone containing compounds on the sample surface. H 3 BO 3 was identified by XRD as a main crystalline specie, additional species (e.g. SiO 2 , Zn 4 O(BO 2 ) 6 ) were also identified. The borate, silicate and phosphate chemical species were then characterized using 1D NMR but no definitive assignments could be given. To specify those assignments, 2D D-HMQC NMR was performed and the formation of amorphous borophosphates and borosilicates was evidenced emphasizing the chemical reactivity between the ingredients of the formulation. It was suggested that these species allow reinforcing the char and improving the fire protective properties of the coatings. This work highlights the particular interest of advanced NMR technique, which provides unique information on the characterization of intumescent char. [ABSTRACT FROM AUTHOR]

In this paper, the fire retardant properties of two magnesium dihydroxide (MDH) were compared into glass fiber reinforced polyamide 6 (PA6 GF). The difference between the additives lies in the presence of a vinylsilane treatment at the surface of one of the two MDH (H5A grade) whereas the other is a non-treated MDH (H5 grade). The investigations showed that better fire properties were obtained with PA6 GF/H5A formulation compared to the PA6 GF/H5 one. More precisely, a higher UL-94 rating, a higher glow wire ignition temperature (GWIT) and a higher time to ignition (TTi) at the mass loss calorimeter (MLC) were obtained. To understand the differences between H5 and H5A in terms of fire performances, the mechanism of degradation of the two fire retarded (FR) formulations was investigated, analyzing both the gas phase and the condensed phase. A significant part of the study was also devoted to the characterization of the ceramic protective layer formed thanks to the use of MDH. The analysis of the gas phase revealed that the degradation products of the two FR formulations were similar. Moreover, as shown by the condensed phase analysis, no chemical reaction occurs between PA6 and H5 or H5A, proving that the MDH surface treatment was not involved in chemical reactions during the processing of the formulation or its degradation. On the contrary, the main differences between the two formulations concern the properties of protective layer formed during the degradation. It was shown that the silane treatment and the MgO formed during MDH dehydration lead to the formation of a cohesive structure between the glass fibers when the material degrades, resulting in a highly insulating and resistant protective layer. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the effect of aluminum trihydroxide (Al(OH)3—ATH) on the surface protection from fire for a styrene butadiene rubber (SBR) provided by ammonium polyphosphate ([NH4PO3] n —APP) is studied. The combustion behaviour is studied by means of Cone Calorimetric tests: a maximum fire retardant effect is observed with 10–12wt.% of APP. ATH, less effective as fire retardant, has been added at 60wt.% to reach comparable results as measured by cone calorimetry for 12wt.% APP. Replacement of ATH in the best performing SBR+12wt.% of APP shows an antagonistic effect with as little as 1wt.% of ATH. The combustion behaviour is explained with the mechanism of interaction between SBR, APP and ATH, in which formation of aluminum phosphates negatively affects the surface protection provided by the ultraphosphate surface coating formed on heating APP in SBR. [Copyright &y& Elsevier]

Competitive interactions between two sessile, epibenthic species were investigated on the Great Barrier Reef (GBR) in the presence and absence of added nutrients, as part of the Enrichment of Nutrients on Coral Reefs Experiment (ENCORE). Sarcophyton ehrenbergi Marenzeller (Octocorallia: Alcyonacea), an alcyonacean soft coral, and Pocillopora damicornis (Linnaeus), a scleractinian coral, were relocated and placed in contact with each other on large plastic grids on each of 12 micro-atolls within the One Tree Island (OTI) lagoon (23°30′S, 152°96′E, GBR). These micro-atolls were allocated in equal-sized groups to three enrichment treatments (addition of nitrogen, N; addition of phosphorus, P; addition of both nitrogen and phosphorus, N+P) and one control. Non-relocated (NR) and relocated colonies were also monitored as controls. After relocation and 1 year of nutrient enrichment, concentrations of a terpenoid complementary metabolite—sarcophytoxide—and wax esters were analyzed in colonies of S. ehrenbergi that had been exposed to elevated concentrations of N, P, N+P and compared with colonies on the non-nutrient-enriched control. Non-relocated control colonies from the natural environment were monitored over a period of 1 year and compared to colonies relocated to the control micro-atolls to assess handling effects. Analyses were performed on non-interacting S. ehrenbergi colonies, S. ehrenbergi colonies in experimental contact with P. damicornis colonies, and on non-interacting S. ehrenbergi colonies from the site of initial collection. Significant differences were found between sarcophytoxide levels in colonies of S. ehrenbergi in contact with P. damicornis vs. control/non-contact colonies; contact colonies had higher levels of this metabolite. Non-relocated control colonies of S. ehrenbergi exhibited significantly higher levels of sarcophytoxide than relocated control colonies. Augmentation of nutrient levels in micro-atolls significantly increased sarcophytoxide levels in S. ehrenbergi colonies relative to colonies on the control micro-atolls, although this response was not strong. Concentrations of fatty esters increased significantly through time in S. ehrenbergi colonies in their natural setting (non-relocated controls). This variability was not observed in relocated colonies in the treatment and control micro-atolls, irrespective of contact with P. damicornis. Concentrations of fatty esters in colonies of S. ehrenbergi in contact with P. damicornis were significantly lower than control/non-contact colonies, indicating that there is a cost in terms of stored energy reserves for the production of additional complementary metabolites when involved in competition for space. Augmentation of P levels in micro-atolls induced significant increases in fatty ester levels within S. ehrenbergi colonies vs. colonies in control micro-atolls, or in micro-atolls treated with added N or N+P together. These findings indicate that interspecific competition for space between a scleractinian coral and an alcyonacean soft coral and/or changes in the environmental nutrient regime can influence concentrations of complementary/secondary metabolites in the alcyonacean coral and the organism''s stored energy reserves. [Copyright &y& Elsevier]

• A model mixture representative of the plastic waste was established. • Pyrolysis of virgin and polymer mixtures was investigated. • The decomposition process is accelerated with polymer mixtures. • The amount of aromatics is higher than expected for PP/ PE and model mixture. Recovery of plastic waste is becoming crucial since the amount of such waste increases continuously. The objective of this study is to investigate the potential of the pyrolysis technique for the recovery of plastic waste. In that frame, the influence of temperature (550°C or 600°C) on the pyrolysis of pure polypropylene (PP), polyethylene (PE), polystyrene (PS) and polyethylene terephthalate (PET) was first studied. It is shown that whatever the type of polymer, aromatic compounds are mainly formed and could reach 55wt.-% of the oil fraction for PP and 31wt.-% for PE at 550°C. In a second step, a PP/PE mixture and a model mixture representative of the packaging plastic waste stream were pyrolyzed to investigate the influence of a combination of polymers on the proportions and composition of the different fractions. The pyrolysis of the polymer mixtures shows that, even if the aromatic compounds formed are similar to those obtained for the virgin polymers, the proportion of aromatic compounds is much more important than when the polymers are pyrolyzed alone. Indeed, mixing PE with PP at a 50/50 ratio does not affect the amount of liquid, gas and solid fractions but leads to the formation of a higher quantity of xylene (39 wt-%) at 550°C. The combination of the plastics in the model mixture has also led to a decrease of the amount of waxy compounds. Furthermore, it was shown that a higher amount of aromatics than expected was formed. As a conclusion, this study demonstrates that pyrolysis is an effective technique to recover plastic waste as aromatic compounds for the petroleum industry. In the specific conditions used in this study (proposed model mixture and pyrolysis conditions), it will favor the idea that sorting is not needed to recover plastic waste through pyrolysis since aromatics formation is favored when the stream is composed of a mixture of polymers. [ABSTRACT FROM AUTHOR]

• A flame retardant and weathering resistant self-stratified coating is designed. • Epoxy stratifies as the base layer and silicone as the upper layer. • Iron oxide and Calcium carbonate fillers migrate to the silicone phase. • The filled coatings yield V0 rating at UL94, high LOI and rise time to ignition at MLC. • The filled coatings are stable under UV, humidity and temperature aging procedures. Lowering fire hazard raised by combustible materials such as plastics may be achieved by the use of suitable flame retardant treatments, like fire protective coatings. However, exposure to long-term environmental conditions can cause loss of their functional properties, thus reducing their effectiveness over time. This is why two or three different layers with specific properties (e.g. adhesive, fire retardant and hydrophobic) are generally needed to provide durable fire retardancy. Effective and economical self-layering coatings can be developed to reduce the number of layers without compromising the advantages of the actual system. In this work, the efficiency of applying a silicone based coating to fire retard polycarbonate and the modification of the behaviors of the system, using a mixture of epoxy/silicone resins, a curing agent and either iron oxide or calcium carbonate as fire retardant filler is investigated. Self-stratification and fillers dispersion were evidenced by microscopic analyses coupled with chemical detection, the flame retardant properties using Limiting Oxygen Index (LOI), UL-94, Mass Loss Calorimetry (MLC), Thermogravimetric analyses (TGA) and a tubular furnace, and aging resistance by accelerated thermal, humidity and UV exposure. It appears that the selected fillers have no negative effect on the layering process when introduced from 2.5 to 10 vol.%: perfect stratification is obtained, with the silicone layer being the top layer. The best improvements in terms of fire retardant properties, adhesion and fillers dispersion were obtained by incorporating 2.5 vol.%: V0 rating at UL-94 and 33 and 35 vol.% at LOI with Fe 2 O 3 and CaCO 3 respectively were measured when a 200 μm wet thick coating was applied. The coating containing iron oxide was unaffected by weathering conditions. Finally, the application of those coatings on polycarbonate allows the formation of a protective barrier which limits substrate/flame mass transfers. It therefore results in (i) a delay of the time to ignition, (ii) the inhibition of the flame spread and of dripping when submitted to a flame, and (iii) a reduction of the combustibility of polycarbonate. A modification of the structure of the silica network formed by the particles which enhances the barrier effect of the silicone-based layer would be the most probable assumption to explain these excellent results. [ABSTRACT FROM AUTHOR]