TY - JOUR A1 - Battig, Alexander A1 - Markwart, J. C. A1 - Wurm, F. R. A1 - Schartel, Bernhard T1 - Matrix matters: Hyperbranched flame retardants in aliphatic and aromatic epoxy resins N2 - We synthesized a library of phosphorus-based flame retardants (phosphates and phosphoramides of low and high molar mass) and investigated their behavior in two epoxy resins (one aliphatic and one aromatic). The pyrolytic and burning behavior of the two resins (via TGA, TG-FTIR, Hot stage FTIR, Py-GC/MS, PCFC, DSC, LOI, UL-94, Cone calorimeter) are analyzed and compared to the results of flame retardant (FR)-containing composites. A decomposition pathway incorporating the identified modes of action and known chemical mechanisms is proposed. The overlap of decomposition temperature (Tdec) ranges of matrix and FR determines the efficacy of the system. Low molar mass FRs strongly impact material properties like Tg but are very reactive, and high molar mass variants are more thermally stable. Varying PeO and PeN content of the FR affects decomposition, but the chemical structure of the matrix also guides FR behavior. Thus, phosphates afford lower fire load and heat release in aliphatic epoxy resins, and phosphoramides can act as additives in an aromatic matrix or a reactive FRs in aliphatic ones. The chemical structure and the structure-property relationship of both FR and matrix are central to FR performance and must be viewed not as two separate but as one codependent system. KW - Flame retardant KW - Phosphate KW - Phosphoramide KW - Epoxy resin KW - Hyperbranched polymer PY - 2019 DO - https://doi.org/10.1016/j.polymdegradstab.2019.108986 SN - 0141-3910 VL - 170 SP - 108986 PB - Elsevier Ltd. AN - OPUS4-49456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Markwart, J. C. A1 - Battig, Alexander A1 - Velencoso, M. M. A1 - Pollok, D. A1 - Schartel, Bernhard A1 - Wurm, F. R. T1 - Aromatic vs. Aliphatic Hyperbranched Polyphosphoesters as Flame Retardants in Epoxy Resins N2 - The current trend for future flame retardants (FRs) goes to novel efficient halogen-free materials, due to the ban of several halogenated FRs. Among the most promising alternatives are phosphorus-based FRs, and of those, polymeric materials with complex shape have been recently reported. Herein, we present novel halogen-free aromatic and aliphatic hyperbranched polyphosphoesters (hbPPEs), which were synthesized by olefin Metathesis polymerization and investigated them as a FR in epoxy resins. We compare their efficiency (aliphatic vs. aromatic) and further assess the differences between the monomeric compounds and the hbPPEs. The decomposition and vaporizing behavior of a compound is an important factor in its flame-retardant behavior, but also the interaction with the pyrolyzing matrix has a significant influence on the performance. Therefore, the challenge in designing a FR is to optimize the chemical structure and its decomposition pathway to the matrix, with regards to time and temperature. This behavior becomes obvious in this study, and explains the superior gas phase activity of the aliphatic FRs. KW - Phosphorus KW - Metathesis KW - Dendritic KW - Cone calorimeter KW - Fire test PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-494535 DO - https://doi.org/10.3390/molecules24213901 SN - 1420-3049 VL - 24 IS - 21 SP - 3901 PB - MDPI AN - OPUS4-49453 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Weathering resistance of halogen-free flame retardancy N2 - Whereas the degradation of flame retardant polymers has been discussed since decades, only more recently, the lifetime of the flame retardancy itself becomes an important factor, e.g. for cables used as building products. In this work, several kinds of accelerated artificial ageing tests are performed simulating different environmental exposures and thus highlighting different degradation mechanisms: artificial accelerated weathering, climatic chamber, water immersion, salt spray chamber, and autoclave test. The durability is expected to be different for different flame-retardant materials. Thus, various sets of halogen-free fire-retarded polymers were investigated: ethylene vinyl acetate (EVA) with aluminum hydroxide (ATH), boehmite and synergists, ester-based and ether-based thermoplastic polyurethane (TPU) with melamine cyanurate (MC), aluminum diethylphosphinate (AlPi), and boehmite, and glass fiber reinforced polyamide 66 (PA66) with AlPi-based mixtures. Intensive degradation of the surface was observed, e.g. yielding discoloration and yellowing, EVA showed cracking when weathered. Changes in chemical structure was investigated by ATR-FTIR. The flammability was investigated with the cone calorimeter, UL-94 classification, and oxygen index (LOI). The flame retardancy of most of the materials studied degraded only slightly for the investigated exposure times. EVA/ATH achieved an improved LOI due to flame retardants agglomeration at the surface. Sets of materials, based on EVA and TPU, were also investigated as cable jackets. While flame retarded EVA exhibited no dripping during burning, TPU flame-retarded with MC cables showed pronounced melt-dripping. Cone calorimeter tests were carried out using cable rafts as well as our self-made cable module test, simulating a vertical bundle of cables at the bench scale. The comparison of different fire tests, different exposure conditions, and different materials carved out the specific degradation phenomena with respect to each of these parameters. Most of this work was supported by the IGF Project (18926 N) of the Fördergemeinschaft für das Süddeutsche Kunststoff-Zentrum e.V., supported by the AiF within the framework of the program “Förderung der Industriellen Gemeinschaftsforschung (IGF)” of the German Federal Ministry for Economic Affairs and Energy based on a decision of the Deutschen Bundestag. T2 - 33rd Polymer Degradation Discussion Group Conference (PDDG-2019) CY - St. Julian, Malta DA - 01.09.2019 KW - Weathering resistance KW - Durability KW - Flame retardancy PY - 2019 AN - OPUS4-49020 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, Sebastian A1 - Sánchez-Olivares, G. A1 - Pérez-Chávez, R. A1 - Schartel, Bernhard T1 - Natural keratin and coconut fibres from industrial wastes in flame retarded thermoplastic starch biocomposites N2 - Natural keratin fibres derived from Mexican tannery waste and coconut fibres from coconut processing waste were used as fillers in commercially available, biodegradable thermoplastic starch-polyester blend to obtain sustainable biocomposites. The morphology, rheological and mechanical properties as well as pyrolysis, flammability and forced flaming combustion behaviour of those biocomposites were investigated. In order to open up new application areas for these kinds of biocomposites, ammonium polyphosphate (APP) was added as a flame retardant. Extensive flammability and cone calorimeter studies revealed a good flame retardance effect with natural fibres alone and improved effectiveness with the addition of APP. In fact, it was shown that replacing 20 of 30 wt. % of APP with keratin fibres achieved the same effectiveness. In the case of coconut fibres, a synergistic effect led to an even lower heat release rate and total heat evolved due to reinforced char residue. This was confirmed via scanning electron microscopy of the char structure. All in all, these results constitute a good approach towards sustainable and biodegradable fibre reinforced biocomposites with improved flame retardant properties. KW - Biomaterials KW - Biodegradable KW - Calorimetry KW - Composites KW - Flame retardance PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-472518 DO - https://doi.org/10.3390/ma12030344 SN - 1996-1944 VL - 12 IS - 3 SP - 344, 1 EP - 24 PB - MDPI AN - OPUS4-47251 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sut, Aleksandra A1 - Metzsch-Zilligen, E. A1 - Großhauser, M. A1 - Pfaendner, R. A1 - Schartel, Bernhard T1 - Synergy between melamine cyanurate, melamine polyphosphate and aluminum diethylphosphinate in flame retarded thermoplastic polyurethane N2 - The multicomponent flame retardant system of melamine polyphosphate (MPP), melamine cyanurate (MC) and aluminum diethylphosphinate (AlPi) is proposed and investigated for thermoplastic polyurethane (TPU). The synergy between those additives and the resulting superior fire performance are discussed. Systematically varied sets of flame retarded TPU with various MPP/MC/AlPi ratios were investigated in terms of fire behavior, pyrolysis products and mechanical properties. The total amount of the additives was always 30 wt.-%. Further, the influence of various AlPi concentrations was investigated. The optimal MPP:MC ratio was determined while keeping the amount of AlPi constant. The combination of 8 wt.-% MPP, 12 wt.-% MC and 10 wt.-% is proposed as the most promising halogen free flame retardant formulation for TPU, because it yielded a reduction in PHRR from 2660 kW/m2 (TPU) to 452 kW/m2 and enabled V-0 classification in the UL 94 test. Combinations of MPP and MC as well a high concentration of AlPi are beneficial for the mechanical properties e.g. tensile strength and elongation at break of the formulations and could be a strong competitor to commercial flame retarded TPUs. KW - Thermoplastic polyurethane KW - Synergy KW - Melamine cyanurate KW - Melamine polyphosphate KW - Aluminum diethylphosphinate KW - Rapid mass calorimeter PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-472523 DO - https://doi.org/10.1016/j.polymertesting.2019.01.001 SN - 0142-9418 VL - 74 SP - 196 EP - 204 PB - Elsevier Ltd. AN - OPUS4-47252 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yin, Huajie A1 - Sypaseuth, Fanni D. A1 - Schubert, M. A1 - Schoch, R. A1 - Bastian, M. A1 - Schartel, Bernhard T1 - Routes to halogen‐free flame‐retardant polypropylene wood plastic composites N2 - Developing halogen‐free flame retardants with reasonably high efficiency, which thus function at limited loadings in polypropylene‐based wood/plastic composites (WPC), is still a challenge. Cost‐effective flame‐retarded WPC have been identified as a way to open the door to an interesting, broader spectrum of application in the building and transportation sectors. This work imparts a systematic comprehensive understanding and assessment of different basic routes to halogen‐free flame‐retarded WPC, taking into account economic and environmental considerations. Cheap, halogen‐free single‐component flame retardants and their multicomponent systems are investigated at reasonable filling grades of 20 wt%. The basic routes of promising synergistic multicomponent systems are discussed, and their potential and Limits assessed. Optimizing the consistency of fire residue; closing the surface of inorganic‐organic residual layers; the thermal stabilization and design of the residue, eg, synergistic combination of ammonium polyphosphate and expandable graphite; and the combination of different flame‐retardant mechanisms, eg, intumescence and flame inhibition, are proposed as promising routes to boost the flame‐retardant efficiency. KW - Flammability KW - Halogen‐free KW - Multicomponent systems KW - Polypropylene KW - Wood plastic composite (WPC) PY - 2019 DO - https://doi.org/10.1002/pat.4458 SN - 1099-1581 SN - 1042-7147 VL - 30 IS - 1 SP - 187 EP - 202 PB - Wiley AN - OPUS4-46909 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schartel, Bernhard A1 - Humphrey, J.K. A1 - Gibson, A.G. A1 - Hörold, Andreas A1 - Trappe, Volker A1 - Gettwert, V. T1 - Assessing the structural integrity of carbon-fibre sandwich panels in fire: Bench-scale approach N2 - The fire resistance of lightweight sandwich panels (SW) with carbon fibre/epoxy skins and a poly(methacryl imide) (PMI) foam core is investigated in compression under direct application of a severe flame (heat flux=200 kW m−2). A bench-scale test procedure was used, with the sample held vertically. The epoxy decomposition temperature was quickly exceeded, with rapid flash-over and progressive core softening and decomposition. There is a change in failure mode depending on whether the load is greater or less than 50% of the unexposed failure load, or in other words if one or two skins carry the load. At high loads, failure involved both skins with a single clear linear separation across each face. There is an inflection in the failure time relationship in the ∼50% load region, corresponding to the time taken for heat to be transmitted to the rear face, along with a change in the rear skin failure mode from separation to the formation of a plastic hinge. The integrity of the carbon front face, even with the resin burnt out, and the low thermal diffusivity of the core, both play key roles in prolonging rear face integrity, something to be borne in mind for future panel design. Intumescent coatings prolong the period before failure occurs. The ratio of times to failure with and without protection is proposed as a measure of their effectiveness. Apart from insulation properties, their adhesion and stability under severe fire impact play a key role. KW - Carbon fibres KW - Sandwich KW - Structural composites KW - Fracture KW - High-temperature properties KW - Surface treatments PY - 2019 DO - https://doi.org/10.1016/j.compositesb.2018.11.077 SN - 1359-8368 VL - 164 SP - 82 EP - 89 PB - Elsevier AN - OPUS4-46908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Digging in the dirt: Using natural fibers from industrial waste in flame retarded thermoplastic starch biocomposites N2 - To exploit application fields beyond packaging for biodegradable materials, flame retardancy and increased mechanical strength are usually required. This work focuses on the flammability of a thermoplastic starch/polyester blend reinforced with natural fibers derived from Mexican industry processes wastes, such as keratin fibers from the tannery industry, coconut fibers (coconut industry), and agave tequilana fibers and henequen fibers from tequila industry. Different fiber contents as well as combinations of varying contents of aluminum trihydroxide, expandable graphite, aluminum diethylphosphinate or ammonium polyphosphate are investigated. It is the goal to propose sustainable waste fibers as adjuvants improving the flame retardancy. This work provides the proof of principle for sustainable biodegradable flame retarded biocomposites. T2 - Flame 2018, 30th Annual Conference on Recent Advances in Flame Retardancy of Polymeric Materials CY - San Antonio, TX, USA DA - 19.05.2019 KW - biocomposite KW - sustainable KW - natural fibers KW - renewable KW - industrial waste KW - sustainability KW - thermoplastic starch KW - flame retardant PY - 2019 AN - OPUS4-48143 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zirnstein, Benjamin A1 - Schulze, Dietmar A1 - Schartel, Bernhard T1 - The impact of polyaniline in phosphorus flame retardant ethylene-propylene-diene-rubber (EPDM) N2 - Usually elastomers are loaded with high amounts of flame retardants to fulfill fire safety requirements. In this study the potential char precursor polyaniline (PANI) and the established fire retardant pentaerythritol (PER) were implemented in ethylene-propylene-diene monomer rubber (EPDM). PANI and PER were used in low loadings (7 phr) and combined with two phosphorous flame retardants, Ammonium polyphosphate (APP) and a piperazine-pyrophosphate/phosphoric acid compound (FP), to boost their performance. A comprehensive study is presented, explaining the impact of PANI on curing and mechanical properties, including compensation for the plasticizer-like effect of APP in EPDM, and improved flame retardancy. In the cone calorimeter test, the combination of EPDM/FP/PANI reduced the effective heat of combustion by 20%. All nine EPDM rubber compounds were investigated with the LOI and UL 94 tests, cone calorimeter, FMVSS 302 and glow wire testing to quantify fire performance. The PANI containing EPDM rubbers, EPDM/APP/PANI and EPDM/FP/PANI outperformed the corresponding PER containing, EPDM/APP/PER and EPDM/FP/PER rubbers in various tests. Moreover, the study investigated the impact of PANI and PER on the mode of action of the phosphorus species and showed that the addition of PANI increased the amount of phosphorus in the condensed phase. To receive a broader understanding of the flame retardant mode of action of PANI in combination with APP and FP, calculations were carried out to estimate the impact of PANI on the protective layer effect. KW - EPDM KW - Rubber KW - Flame retardant KW - Polyaniline KW - Pentaerythritol PY - 2019 DO - https://doi.org/10.1016/j.tca.2019.01.019 SN - 0040-6031 VL - 673 SP - 92 EP - 104 PB - Elsevier B.V. AN - OPUS4-47503 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schartel, Bernhard T1 - Understanding flame retardant modes of action: a wellspring for evidence-based development N2 - Although the main flame retardant modes of action are known, in practise the detailed scientific understanding usually falls short, when it comes to modern multicomponent systems, the important tiny optimizations, or quantifying in terms of specific fire properties. The description of the flame retardant modes of action remains usually vague and fragmentary. This talk tries to deliver thought-provoking impulses how the understanding of the fire behaviour and flame retardancy can be utilized to direct the development of future flame retardant polymer products. Some overseen details are picked up as well as rethinking of concepts memorised long ago is encouraged to discover something new. Furthermore, the talk tries to fill the gap between flame retardant modes of action and fire performance constituting a product. This talk promotes the evidence-based development of flame retardant polymers T2 - FRPM 2019, 17th European Meeting on Fire Retardant Polymeric Materials CY - Turku, Finland DA - 26.06.2019 KW - Flame retardant KW - Modes of action KW - Fire behaviour PY - 2019 AN - OPUS4-48551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Battig, Alexander A1 - Markwart, J. C. A1 - Wurm, F. R. A1 - Schartel, Bernhard T1 - Hyperbranched phosphorus flame retardants: multifunctional additives for epoxy resins N2 - We successfully synthesized multifunctional P-based hyperbranched polymeric flame retardants (hb-FRs) with varying oxygen-to-nitrogen (O : N) content and characterized them via 1H and 31P NMR and GPC. Their miscibility in epoxy resins (EP) and impact on glass-transition temperatures (Tg) were determined via differential scanning calorimetry (DSC). Using thermogravimetric and evolved gas Analysis (TGA, TG-FTIR), pyrolysis gas chromatography/mass spectrometry (Py-GC-MS), hot stage FTIR, flammability tests UL-94 and LOI, fire testing via cone calorimetry, residue analysis via scanning electron microscopy (SEM) and elemental analysis, detailed decomposition mechanisms and modes of action are proposed. hb-polymeric FRs have improved miscibility and thermal stability, leading to high FR performance even at low loadings. Polymeric, complex FRs increase flame retardancy, mitigate negative effects of low molecular weight variants, and can compete with commercial aromatic FRs. The results illustrate the role played by the chemical structure in flame retardancy and highlight the potential of hb-FRs as multifunctional additives. KW - Flame retardant KW - Hyperbranched PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-486589 DO - https://doi.org/10.1039/c9py00737g SN - 1759-9962 SN - 1759-9954 VL - 10 IS - 31 SP - 4346 EP - 4358 PB - RSC AN - OPUS4-48658 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wagner, Jan A1 - Häfner, P. A1 - Reimann, H.-A. A1 - Schartel, Bernhard T1 - Valorization of Natural Fibers in Flame Retarded Poly(lactic acid) N2 - Extensive research has explored natural fiber reinforced composites, typically focusing on a single fiber within a polymer matrix. Comprehensive comparisons across different natural fibers in the same polymer, which are critical for industrial material selection, remain limited. This work presents a systematic comparison of untreated hemp, flax, and sisal fibers incorporated at varying fiber lengths and loadings into flame retarded poly(lactic acid) (PLA). Fire behavior, thermal, and mechanical responses were investigated through thermogravimetry, UL 94, and cone calorimetry, alongside crystallinity, molecular weight (MW), and microstructural analysis. Fiber incorporation reduced the peak heat release rate (pHRR) by up to 30 % in 30 wt% hemp, attributed to protective layer formation, but increased flammability in UL 94. A phytic acid melamine salt combined with expandable graphite and 20 wt% hemp produced incomplete combustion at 50 kW/m², raising char residue from 4 to 24 wt% and halving pHRR. Petrella plots revealed that fiber addition alone lowered fire load and flashover propensity as effectively as phytic acid melamine; with hemp, phytic acid and expendable graphite, the flashover hazard and fire load were halved. MW was preserved while crystallinity and modulus increased with fiber content. Hemp delivered the most consistent reinforcement, while optimized processing enabled flax and sisal to improve stiffness. Performance gains were strongest when individual fibers were dispersed via optimized processing, preventing bundle fracture under load. Plasma modification of the fibers improved the maximum tensile strength in the composites. A practical guide is provided for valorizing natural fibers in PLA composites, demonstrating routes to bio-based, compostable materials with improved fire safety and mechanical performance suitable for industrial processing. KW - Poly(lactic acid) KW - Hemp KW - Sisal KW - Flax KW - Flame retardant KW - Phytic acid PY - 2026 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-653038 DO - https://doi.org/10.1016/j.mtcomm.2025.114575 SN - 2352-4928 VL - 50 SP - 1 EP - 41 PB - Elsevier Ltd. AN - OPUS4-65303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dittrich, Bettina A1 - Wartig, K.-A. A1 - Mülhaupt, R. A1 - Schartel, Bernhard T1 - Flame-retardancy properties of intumescent ammonium poly(phosphate) and mineral filler magnesium hydroxide in combination with graphene N2 - Thermally reduced graphite oxide (TRGO), containing only four single carbon layers on average, was combined with ammonium polyphosphate (APP) and magnesium hydroxide (MH), respectively, in polypropylene (PP). The nanoparticle's influence on different flame-retarding systems and possible synergisms in pyrolysis, reaction to small flame, fire behavior and mechanical properties were determined. TRGO has a positive effect on the yield stress, which is decreased by both flame-retardants and acts as a synergist with regard to Young's modulus. The applicability and effects of TRGO as an adjuvant in combination with conventional flame-retardants depends strongly on the particular flame-retardancy mechanism. In the intumescent system, even small concentrations of TRGO change the viscosity of the pyrolysing melt crucially. In case of oxygen index (OI) and UL 94 test, the addition of increasing amounts of TRGO to PP/APP had a negative impact on the oxygen index and the UL 94 classification. Nevertheless, systems with only low amounts (≤1 wt%) of TRGO achieved V-0 classification in the UL 94 test and high oxygen indices (>31 vol%). TRGO strengthens the residue structure of MH and therefore functions as a strong synergist in terms of OI and UL 94 classification (from HB to V-0). KW - Graphene KW - Intumescence KW - Ammonium polyphosphate KW - Magnesium hydroxide KW - Synergy KW - Polypropylene PY - 2014 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-320685 DO - https://doi.org/10.3390/polym6112875 SN - 2073-4360 VL - 6 IS - 11 SP - 2875 EP - 2895 PB - MDPI CY - Basel AN - OPUS4-32068 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rabe, Sebastian A1 - Chuenban, Yuttapong A1 - Schartel, Bernhard T1 - Exploring the Modes of Action of Phosphorus-Based Flame Retardants in Polymeric Systems N2 - Phosphorus-based flame retardants were incorporated into different, easily preparable matrices, such as polymeric thermoset resins and paraffin as a proposed model for polyolefins and investigated for their flame retardancy performance. The favored mode of action of each flame retardant was identified in each respective system and at each respective concentration. Thermogravimetric analysis was used in combination with infrared spectroscopy of the evolved gas to determine the pyrolysis behavior, residue formation and the release of phosphorus species. Forced flaming tests in the cone calorimeter provided insight into burning behavior and macroscopic residue effects. The results were put into relation to the phosphorus content to reveal correlations between phosphorus concentration in the gas phase and flame inhibition performance, as well as phosphorus concentration in the residue and condensed phase activity. Total heat evolved (fire load) and peak heat release rate were calculated based on changes in the effective heat of combustion and residue, and then compared with the measured values to address the modes of action of the flame retardants quantitatively. The quantification of flame inhibition, charring, and the protective layer effect measure the non-linear flame retardancy effects as functions of the phosphorus concentration. Overall, this screening approach using easily preparable polymer systems provides great insight into the effect of phosphorus in different flame retarded polymers, with regard to polymer structure, phosphorus concentration, and phosphorus species. KW - Flame retardants KW - Flame inhibition KW - Cone calorimeter KW - Aluminum diethyl phosphinate KW - Polyester KW - PMMA KW - Epoxy resin KW - Red phosphorus KW - BDP PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-402731 DO - https://doi.org/10.3390/ma10050455 SN - 1996-1944 VL - 10 IS - 5 SP - 455, 1 EP - 455, 23 PB - MDPI AN - OPUS4-40273 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Matzen, Melissa A1 - Kandola, B. A1 - Huth, Christian A1 - Schartel, Bernhard T1 - Influence of flame retardants on the melt dripping behaviour of thermoplastic polymers N2 - Melt flow and dripping of the pyrolysing polymer melt can be both a benefit and a detriment during a fire. In several small-scale fire tests addressing the ignition of a defined specimen with a small ignition source, well-adjusted melt flow and dripping are usually beneficial to pass the test. The presence of flame retardants often changes the melt viscosity crucially. The influence of certain flame retardants on the dripping behaviour of four commercial polymers, poly(butylene terephthalate) (PBT), polypropylene (PP), polypropylene modified with ethylene-propylene rubber (PP-EP) and polyamide 6 (PA 6), is analysed based on an experimental monitoring of the mass loss due to melt dripping, drop size and drop temperature as a function of the furnace temperature applied to a rod-shaped specimen. Investigating the thermal transition (DSC), thermal and thermo-oxidative decomposition, as well as the viscosity of the polymer and collected drops completes the investigation. Different mechanisms of the flame retardants are associated with their influence on the dripping behaviour in the UL 94 test. Reduction in decomposition temperature and changed viscosity play a major role. A flow limit in flame-retarded PBT, enhanced decomposition of flame-retarded PP and PP-EP and the promotion of dripping in PA 6 are the salient features discussed. KW - Fire retardant KW - Viscosity KW - Melt dripping KW - Reaction-to-small-flame KW - UL 94 PY - 2015 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-338941 DO - https://doi.org/10.3390/ma8095267 SN - 1996-1944 VL - 8 IS - 9 SP - 5621 EP - 5646 PB - MDPI CY - Basel AN - OPUS4-33894 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, S. A1 - Wachtendorf, Volker A1 - Klack, Patrick A1 - Qian, Lijun A1 - Dong, Y. A1 - Schartel, Bernhard T1 - Enhanced flame-retardant effect of montmorillonite/phosphaphenanthrene compound in an epoxy thermoset N2 - A phosphaphenanthrene and triazinetrione group containing flame retardant (TAD) is combined with organically modified montmorillonite (OMMT) in epoxy resin thermosets (EP) to improve the performance of the flame-retardant system. When only 1 wt% OMMT/4 wt% TAD is introduced into the EP, the limited oxygen index (LOI) rises from 26% to 36.9% and a V-0 rating is achieved in a UL 94 test. The decomposition and pyrolysis products in the gas phase and condensed phase were characterized using thermogravimetry-Fourier transform infrared spectroscopy (TG-FTIR). The influence on the decomposition of EP, such as the increase in char yield, is limited with the incorporation of OMMT; a large amount of the phosphorus is released into the gas phase. The flame-retardant effect evaluation based on cone calorimeter data testified that OMMT improves the protective-barrier effect of the fire residue of OMMT/TAD/EP on the macroscopic scale, while TAD mainly causes flame inhibition. The fire residues showed a corresponding macroscopic appearance (digital photo) and microstructure (scanning electron microscope [SEM] results). The protective barrier effect of OMMT and the flame-inhibition effect of TAD combined to exert a superior flame-retardant effect, resulting in sufficient flame-retardant performance of OMMT/TAD/EP KW - Flame retardant KW - Nanocomposite KW - DOPO KW - Thermoset KW - Epoxy resin KW - TG-FTIR PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-388865 DO - https://doi.org/10.1039/c6ra25070j SN - 2046-2069 VL - 7 IS - 2 SP - 720 EP - 728 AN - OPUS4-38886 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Daus, Lars-Hendrik A1 - Korzen, Manfred A1 - Schartel, Bernhard T1 - High-throughput fire tests and weathering-induced degradation behaviour of intumescent coatings N2 - In this work, the weathering-induced degradation of intumescent coatings was investigated by a systematic and comprehensive approach. A mechanism is revealed that is proposed to be responsible for the loss of function of intumescent coatings induced by weathering. First, the thermal decomposition of artificially weathered intumescent coatings was examined. To get a better understanding of the weathering and ageing phenomena, the degradation behaviour of the single ingredients during the weathering process was investigated, as well as their chemical and physical interactions. For the systematic approach, the materials that are essential for intumescence (ammonium polyphosphate, pentaerythritol, titanium dioxide, melamine and the binder) are treated with moisture, elevated temperature and UV radiation. Thermogravimetry (TG) and IR spectroscopy were used to compare the initial samples with their different grades of weathering. We demonstrate that ammonium polyphosphate, melamine and the binder are mainly responsible for the ageing process. Further, it was demonstrated that TG and IR spectroscopy are suitable measuring methods to detect the effects of weathering on intumescent coatings. Finally, a small-scale fire test procedure is introduced. Based on the reduction of the sample size, up to 50 samples can be tested in a single fire test. The results of this fire test have the same quality as the results from standard intermediate fire tests corresponding to DIN 4102-8. T2 - 3rd European Symposium on Fire Safety Science CY - Nancy, France DA - 12.09.1018 KW - Weathering KW - Intumescent coatings KW - High-Throughput Fire Tests PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-472023 UR - http://iopscience.iop.org/article/10.1088/1742-6596/1107/3/032014/pdf DO - https://doi.org/10.1088/1742-6596/1107/3/032014 VL - 1107 SP - 032014 PB - IOP Publishing CY - Bristol AN - OPUS4-47202 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Dudziak, Mateusz A1 - Dural, Esra A1 - Dey, R. A1 - Ullrich, M. S. A1 - Huth, Christian A1 - Thomson, C. A1 - Schartel, Bernhard T1 - Together We Can: Synergistic Flame Retardancy by Melamine Polyphosphate and Phosphorylated Microalgae in Polylactide Biocomposites N2 - A strategy for enhancing the sustainable flame retardancy of polylactide (PLA) composites by partially replacing melamine polyphosphate (MPP), a commercial flame retardant proposed for PLA, with wastewater polyphosphate-enriched microalgae (P-Algae) has been explored. The incorporation of P-Algae at a 1:1 ratio with MPP leads to a notable synergistic effect, surpassing the expected additive behavior of the individual components. Comprehensive characterization encompassing thermogravimetric analysis coupled with FTIR, pyrolysis combustion flow calorimeter (PCFC), cone calorimeter, oxygen index (LOI), UL-94 tests, and rheological measurements—demonstrates that the presence of this biomaterial can significantly enhance flame retardant performance. Replacing 50% of MPP with P-Algae in PLA resulted in a 17% reduction in peak heat release rate (pHRR) and maintained a V-0 rating in UL-94 testing. The use of P-Algae does not compromise the flame retardancy of PLA but rather contributes positively, offering a promising path toward more sustainable flame-retardant systems. By leveraging naturally derived biomass, this approach aligns with the growing demand for novel eco-friendly technologies in polymer engineering. Insights into an innovative renewable additive as a functional and effective component in flame-retardant biocomposites have been achieved. KW - Flame retardancy KW - Melamine polyphosphate KW - Phosphorus- enriched microalgae KW - Polylactide PLA KW - Synergism PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-640539 DO - https://doi.org/10.1002/pat.70350 SN - 1099-1581 SN - 1042-7147 VL - 36 IS - 9 SP - e70350 PB - John Wiley & Sons Ltd. AN - OPUS4-64053 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Watolla, Marie-Bernadette A1 - Gluth, Gregor A1 - Sturm, Patrick A1 - Rickard, W.D.A. A1 - Krüger, Simone A1 - Schartel, Bernhard T1 - Intumescent geopolymer-bound coatings for fire protection of steel N2 - The passive fire protection of steel structures and other load-bearing components will continue to gain importance in future years. In the present contribution, novel intumescent aluminosilicate (geopolymer-bound) composites are proposed as fire-protective coatings on steel. Steel plates coated with these materials were exposed to the standard temperature-time curve as defined in ISO 834 – 1:1999. The coatings partially foamed during curing and expanded further during thermal exposure, demonstrating their intumescent characteristic.Thermogravimetryandoscillatory rheometry determined that the intumescent behavior is attributed to a transition to a viscous state (loss factor > 1) in the temperature range of major water release, differing from conventional geopolymers. XRD and SEM images showed that the coatings had characteristics of ceramic or glass-ceramic foams after fire resistance testing, suggesting superior performance under challenging conditions. The thickness of the coatings influenced their foaming and intumescent behavior and thus the time for the coated steel plates to reach 500 °C. A number of additives were also studied with the best performance obtained from samples containing sodium tetraborate.Acoating of just 6mmwas able to delay the time it takes for a steel substrate to reach 500 °C to more than 30 minutes. KW - Geopolymers KW - Fire protection KW - Intumescence KW - Coatings KW - Fire resistance PY - 2017 UR - https://www.ceramic-science.com/articles/all-articles.html?article_id=100558 DO - https://doi.org/10.4416/JCST2017-00035 VL - 8 IS - 3 (Topical issue: Geopolymers) SP - 351 EP - 364 PB - Göller Verlag CY - Baden-Baden AN - OPUS4-42139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Gluth, Gregor A1 - Watolla, Marie-Bernadette A1 - Morys, Michael A1 - Häßler, Dustin A1 - Schartel, Bernhard T1 - Neue Wege: Reaktive Brandschutzbeschichtungen für Extrembedingungen N2 - Wesentlich für das Sicherheitsniveau und damit die nachhaltige Wettbewerbsfähigkeit des Technologiestandortes Deutschland ist der Brandschutz in Industrieanlagen, in Gebäuden und im Transportwesen. Der vorbeugende bauliche Brandschutz hat u. a. das Ziel, die Brand- und Rauchausbreitung im Brandfall für eine gewisse Zeit zu behindern, damit die erforderlichen Lösch- und Rettungsarbeiten durchgeführt werden können. Dies geschieht u.a. durch Anforderungen an die Feuerwiderstandsfähigkeit brandbeanspruchter Bauteile. Der Feuerwiderstand eines Bauteils ist die Fähigkeit während eines angegebenen Zeitraums in einer genormten Feuerwiderstandsprüfung bezüglich mechanischer Stabilität und/oder thermischer Isolierung nicht zu versagen. Reaktive Brandschutzbeschichtungen erhöhen für viele Bauteile sehr effektiv den Feuerwiderstand. Die Beschichtungen und die Brandprüfungen müssen jedoch an die immer komplexeren Anwendungen und/oder extremeren Anforderungen angepasst und weiterentwickelt werden. Aktuelle Forschungsschwerpunkte liegen dabei in der Entwicklung neuer Materialien (z.B. Geopolymere, keramisierende Beschichtungen, silikonbasierte Beschichtungen) für extreme Brandszenarien (extreme Temperaturen, lange Beanspruchungszeiten) und in der Realisierung komplexer Funktionalitäten (komplexe Geometrien, bewegliche Komponenten) sowie in der Entwicklung neuer Testmethoden (Feuerwiderstand als bench-scale Tests, kostengünstiges Screening, Feuerwiderstand in extremen Brandszenarien). Die Entwicklung geht dabei weg von der präskriptiven Bewertung hin zur leistungsorientierten (performance-based) Bewertung in individuellen Brandszenarien oder von komplexen Bauteilen. Im Rahmen dieser Arbeit werden Lösungsansätze für die neuen Herausforderungen an die reaktiven Brandschutzsysteme unter Extrembedingungen und deren Testmöglichkeiten vorgestellt und diskutiert. Im Mittelpunkt stehen dabei neu entwickelte bench-scale Testmethoden zum Screening von neuen Beschichtungsmaterialien sowie zur Beurteilung spezieller bzw. materialspezifischer Aspekte des Feuerwiderstands unter Extrembedingungen. KW - Reaktive Brandschutzsysteme KW - Brandtest PY - 2016 DO - https://doi.org/10.1002/bate.201600032 SN - 0932-8351 SN - 1437-0999 VL - 93 IS - 8 SP - 531 EP - 542 PB - Ernst & Sohn CY - Berlin AN - OPUS4-37115 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -