TY - JOUR A1 - Krüger, Simone A1 - Brademann-Jock, Kerstin A1 - Rauth, W. A1 - Klimmasch, T. A1 - Krüger, P. T1 - Analysis of weathering effects in automotive coatings using thermoluminescence N2 - Thermally stimulated luminescence (TL) can be used to detect damage in the early stages of degradation after artificial weathering, and to analyze the efficiency of stabilizers used in automotive coatings. TL is particularly suitable for this task due to its inherent high sensitivity to structural, morphological, and chemical changes in macromolecular chains. In this work, TL measurements were carried out for different automotive coatings to follow their degradation progression during artificial weathering. The TL results demonstrate high sensitivity to parameters like stabilizers, matrices, hardeners, and weathering time, and provide an opportunity to monitor the early stages of damage in polymers, which therefore reduce the time required for further outdoor weathering tests. KW - Accelerated weathering KW - Automotive coating KW - Thermoluminescence KW - Sensitive detection KW - Weathering PY - 2008 DO - https://doi.org/10.1007/s11998-007-9072-6 SN - 1547-0091 SN - 1935-3804 VL - 5 IS - 1 SP - 11 EP - 16 PB - Springer CY - Blue Bell, Pa. AN - OPUS4-16722 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Wachtendorf, Volker A1 - Rauth, W. A1 - Klimmasch, T. A1 - Krüger, P. T1 - Screening the weathering stability of automotive coatings by chemiluminescence N2 - Chemiluminescence (CL) is a sensitive method of investigating the thermo-oxidative stability of polymers in the early stages of degradation. Therefore, CL measurements were applied to different automotive coatings to evaluate their degradation behavior during artificial weathering. In this work, CL measurements were carried out for different automotive coatings to follow their degradation behavior during artificial weathering. The CL emission depends on sample-specific parameters like stabilizer, matrix, or hardener; experimental parameters like the oxygen partial pressure; and exposure parameters like the duration of weathering. The potential of CL could be demonstrated by classifying materials into categories of good, medium, and low degradation performance at a much earlier stage of weathering exposure than in combination with the usual visual detection of weathering effects. KW - Accelerated weathering KW - Coating KW - Chemiluminescence KW - Sensitive detection KW - Weathering PY - 2008 DO - https://doi.org/10.1007/s11998-007-9071-7 SN - 1547-0091 SN - 1935-3804 VL - 5 IS - 1 SP - 17 EP - 24 PB - Springer CY - Blue Bell, Pa. AN - OPUS4-16723 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Morys, Michael A1 - Häßler, Dustin A1 - Krüger, Simone A1 - Schartel, Bernhard A1 - Hothan, Sascha T1 - Beyond the standard time-temperature curve: Assessment of intumescent coatings under standard and deviant temperature curves N2 - Nowadays there are intumescent coatings available for diverse applications. There is no established assessment of their protection performance besides the standard time-temperature curve, but natural fire scenarios often play an important role. A reliable straightforward performance-based assessment is presented. The effective thermal conductivity per thickness is calculated based on intermediate-scale fire tests. The optimum thermal insulation, the time to reach it, and the time until contingent failure of the coating are used for an assessment independent of the heating curve. The procedure was conducted on four different commercially intumescent coatings for steel construction, one solvent-based, one waterborne, one epoxy-based, and a bandage impregnated with a waterborne coating. The performance was studied under four different but similar shaped heating curves with different maximum temperatures (standard time-temperature curve, hydrocarbon curve and two self-designed curves with reduced temperature). The thermal protection performance is crucially affected by the residue morphology. Therefore, a comprehensive morphology analysis, including micro-computed tomography and scanning electron microscopy, was conducted on small-scale residues (7.5 x 7.5 cm2). Two different types of inner structures and the residue surface after different heat exposures were discussed in terms of their influence on thermal protection performance. KW - Intumescence KW - Coating KW - Computed tomography KW - Small scale KW - Heating curves KW - Residue morphology PY - 2020 DO - https://doi.org/10.1016/j.firesaf.2020.102951 SN - 0379-7112 VL - 112 SP - 102951 PB - Elsevier Ltd. AN - OPUS4-50334 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hahn, A. A1 - Zellmer, S. A1 - Riesselmann, B. A1 - Krüger, Simone A1 - Raspe, Tina A1 - Schwarz, Silke A1 - Stahn, Sebastian A1 - Urban, Klaus T1 - Carbon monoxide release curves from measurements during indoor charcoal burning: systematic research on toxic levels for humans N2 - The Federal Institute for Risk Assessment (BfR) DocCenter has received more and more reports of cases of carbon monoxide (CO) poisoning, some even with fatal outcomes after indoor use of charcoal grills. CO is odorless, colorless, non-irritant and does not produce any other warning effect perceptible to humans. The BfR and the Federal Institute for Materials Research and Testing (BAM) have completed a cooperative research project to investigate the toxic concentrations of CO that are reached when charcoal grills or open fires are used indoors. KW - Toxicity KW - Indoor charcoal burning PY - 2014 DO - https://doi.org/10.3109/15563650.2014.906213 SN - 1556-3650 VL - 52 IS - 4 SP - 351 PB - Informa Healthcare CY - Philadelphia, Pa. AN - OPUS4-34582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Farag, Zeinab Ramadan A1 - Friedrich, Jörg Florian A1 - Krüger, Simone A1 - Hidde, Gundula A1 - Moustapha, M. E. T1 - Adhesion promotion of thick polyphosphate-poly(allylamine) films onto polyolefin substrates by plasma polymers N2 - The adhesion of thick poly(allylamine)-polyphosphate layers (1 µm) deposited by the wet-chemical layer-by-layer technique (LbL) onto polyethylene or polystyrene (each 100 µm) was very low. To promote the adhesion of these LbL layers the polyolefin substrates were oxidized at the surface by short exposure to the oxygen plasma (2 or 5 s) and subsequently coated with an interlayer of plasma-deposited poly(allylamine) or poly(allyl alcohol) (100 nm). The plasma polymer interlayers have improved strongly the adhesion between polyolefin substrates and polyphosphate coatings. Such phosphate coatings are interesting for life sciences (nucleotide formation) but also for fire retardancy in combination with N-rich compounds such as melamine. The intention was to prefer chemical and hydrogen bonds for adhesion promoting because of their high binding energy. Therefore, the introduced oxygen-containing groups at the polyolefin surface could interact with the OH or NH2 groups of the adhesion-promoting plasma polymer interlayer. These groups were also able to interact strongly with the poly(allylamine)-polyphosphate topcoating. The coated polyolefins were investigated using Fourier Transform Infrared Spectroscopy in Attenuated Total Reflectance mode (FTIR-ATR), X-ray Photoelectron Spectroscopy (XPS), Thermo-Gravimetric Analyses (TGA) and Atomic Force Spectroscopy (AFM) and 90° peel test. KW - Plasma-polymerized poly(allylamine) KW - Adhesion KW - Layer-by-layer deposition KW - Plasma polymerization PY - 2016 UR - http://www.tandfonline.com/doi/abs/10.1080/01694243.2015.1095626 DO - https://doi.org/10.1080/01694243.2015.1095626 SN - 1648-4142 VL - 30 IS - 3 SP - 231 EP - 246 PB - Taylor & Francis AN - OPUS4-35885 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bonse, Jörn A1 - Höhm, S. A1 - Koter, Robert A1 - Hartelt, Manfred A1 - Spaltmann, Dirk A1 - Pentzien, Simone A1 - Rosenfeld, A. A1 - Krüger, Jörg T1 - Tribological performance of sub-100-nm femtosecond laser-induced periodic surface structures on titanium N2 - Sub-100-nm laser-induced periodic surface structures (LIPSS) were processed on bulk titanium (Ti) surfaces by femtosecond laser pulse irradiation in air (30 fs pulse duration, 790 nm wavelength). The laser peak fluence, the spatial spot overlap, and the number of overscans were optimized in a sample-scanning geometry in order to obtain large surface areas (5 mm × 5 mm) covered homogeneously by the LIPSS. The laser-processed regions were characterized by optical microscopy (OM), white light interference microscopy (WLIM) and scanning electron microscopy (SEM). The friction coefficient of the nanostructured surfaces was tested during 1000 cycles under reciprocal sliding conditions (1 Hz, 1.0 N normal load) against a 10-mm diameter ball of hardened 100Cr6 steel, both in paraffin oil and in engine oil used as lubricants. Subsequently, the corresponding wear tracks were qualified by OM, SEM, and energy dispersive X-ray analyses (EDX). The results of the tribological tests are discussed and compared to that obtained for near wavelength-sized fs-LIPSS, processed under somewhat different irradiation conditions. Some constraints for a beneficial effect of LIPSS on the tribological performance are provided. KW - Femtosecond laser ablation KW - Laser-induced periodic surface structures, LIPSS KW - Friction KW - Wear KW - Nanostructures KW - Surface functionalization PY - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0169433215026987 DO - https://doi.org/10.1016/j.apsusc.2015.11.019 SN - 0169-4332 SN - 1873-5584 VL - 374 SP - 190 EP - 196 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-35937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Häßler, M. A1 - Hothan, Sascha A1 - Krüger, Simone T1 - Reaktive Brandschutzsysteme auf Stahlbauteilen mit doppelt gekrümmter Oberfläche N2 - Reaktive Brandschutzsysteme können die Feuerwiderstandsdauer von Stahlbauteilen signifikant erhöhen. Im Brandfall schäumt das reaktive Brandschutzsystem auf und bildet um das Stahlbauteil eine thermische Schutzschicht aus. Dadurch wird die Erwärmung des Stahls verlangsamt und der temperaturbedingte Festigkeitsverlust verzögert. Reaktive Brandschutzsysteme werden überwiegend in drei Bereichen angewendet: Hochbau, Offshore bzw. maritimer Sektor sowie Tank- bzw. Behälterbau. Insbesondere bei Stahltanks und -behältern sind häufig einfach oder auch doppelt gekrümmte Bauteiloberflächen anzutreffen. Aufgrund des meist begrenzten seitlichen Expansionsvermögens von reaktiven Brandschutzsystemen kann es bei Bauteilen mit konvexer Oberflächenkrümmung zu einer Intensivierung der Rissbildung im Schaum kommen, wodurch sich häufig die thermische Schutzwirkung verschlechtert. Da zum Thema des Einflusses der Oberflächenkrümmung auf die Leistungsfähigkeit reaktiver Brandschutzsysteme bisher kaum Untersuchungen vorliegen, wurden exemplarisch zwei Tankböden mit zwei verschiedenen Trockenschichtdicken eines reaktiven Brandschutzsystems einer Brandprüfung unterzogen. Bei gleicher Trockenschichtdicke des reaktiven Brandschutzsystems zeigten die Tankböden eine wesentlich schnellere Erwärmung als ebene Stahlplatten mit vergleichbarem Profilfaktor. Die Brandprüfungen und die Ergebnisse zum Einfluss der Oberflächenkrümmung werden im Beitrag ausführlich vorgestellt und diskutiert. KW - Brandschutz KW - Stahl KW - Reaktive Brandschutzsysteme KW - Behälter KW - Intumeszierende Beschichtung PY - 2020 DO - https://doi.org/10.1002/stab.201900095 VL - 89 IS - 9 SP - 794 EP - 800 PB - Ernst & Sohn Verlag CY - Berlin AN - OPUS4-51242 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Hothan, Sascha A1 - Häßler, M. A1 - Krüger, Simone T1 - Thermische Schutzwirkung von reaktiven Brandschutzsystemen auf kleinformatigen Stahlbauteilen mit gekrümmter Oberfläche T1 - Thermal protection effect of reactive fire protection systems on small-scale steel components with curved surfaces N2 - Um Stahlbauteile im Brandfall vor einer zu schnellen Erwärmung zu schützen, wird häufig auf reaktive Brandschutzsysteme (RBS) zurückgegriffen. Die Produkte eigenen sich besonders aufgrund der profilfolgenden Applikationsmöglichkeit und der vergleichsweise geringen Beschichtungsdicken. Bei einer Brandbeanspruchung schäumt das RBS auf und bildet eine thermische Schutzschicht um das Stahlprofil aus. Dadurch wird die Erwärmung des Stahls verlangsamt und der temperaturbedingte Festigkeitsverlust verzögert, wodurch sich die Feuerwiderstandsdauer des Stahlbauteils verbessert. Aus Brandversuchen ist bekannt, dass die Leistungsfähigkeit von RBS auf Stahlprofilen mit gekrümmter Oberfläche meist schlechter ausfällt als bei vergleichbaren Bauteilen mit ebener Oberfläche. Zum Einfluss der Oberflächenkrümmung auf die thermische Schutzwirkung von RBS werden in dem folgenden Beitrag sowohl theoretische Hintergründe als auch die Ergebnisse aus Brandversuchen an kleinformatigen Probekörpern vorgestellt. Die systematischen Untersuchungen zeigen, dass mit zunehmender Oberflächenkrümmung die Leistungsfähigkeit des RBS tendenziell abnimmt. Bei der Beurteilung der thermischen Schutzwirkung eines RBS sollte die Oberflächenkrümmung eines Bauteils berücksichtigt werden. Die alleinige Fokussierung auf den Profilfaktor eines Stahlprofils ist im Allgemeinen nicht ausreichend. Die Untersuchungen bilden die Grundlage für die Entwicklung von Screening-Tests zur Beurteilung der Eignung von RBS für gekrümmte Oberflächen, wodurch eine Vorauswahl von Produkten für diesen Einsatzzweck ermöglicht wird. N2 - Intumescent fire protection coatings, also referred to as reactive fire protection systems, are often used to protect steel components from heating up too quickly in the event of a fire. The products are particularly suitable due to profile-following application as well as the comparatively low coating thickness. If exposed to fire, the intumescent coating foams up and forms a thermal protective layer around the steel profile. This slows down the heating of the steel and delays the temperature-related loss of strength, which improves the fire resistance of the steel component. From fire tests it is known that the performance of intumescent coatings on steel profiles with a curved surface is usually worse than on comparable components with a flat surface. The following article presents the theoretical background as well as the results from fire tests on small-scale specimens to show the influence of surface curvature on the thermal protective effect of intumescent fire protection coatings. The systematic investigations show that with increasing surface curvature, the performance of the intumescent coating tends to decrease. When assessing the thermal protective effect of an intumescent coating, the surface curvature of a steel component should be considered. Focusing solely on the profile factor of a steel profile is generally not sufficient. The research forms the basis for the development of screening tests to assess the suitability of intumescent coatings for curved surfaces, enabling a pre-selection of products for this application. KW - Stahl KW - Brandschutz KW - Reaktive Brandschutzsysteme KW - Brandversuche KW - Oberflächenkrümmung KW - Intumeszierende Beschichtung PY - 2021 DO - https://doi.org/10.1002/bate.202100011 SN - 0932-8351 SN - 1437-0999 VL - 98 IS - 5 SP - 333 EP - 344 PB - Ernst & Sohn Verlag CY - Berlin AN - OPUS4-52654 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goller, Sebastian M. A1 - Schartel, Bernhard A1 - Krüger, Simone T1 - Block it and rock it: Smoke suppressants that form a protective layer in PA 6.6 N2 - To ensure fire safety, polymers are filled with flame retardants and smoke suppressants. To meet the highest requirements, it is essential to understand the decomposition of those polymeric materials. This study reveals interactions between polymer, smoke suppressants, and flame retardants, and discusses their impact on the materials’ flame retardancy, smoke emission, smoke toxicity, and particle emission in conventional loadings to provide deeper general understanding. Low melting oxide glass, melem, spherical silica, sepiolite, melamine polyphosphate, and boehmite in an aluminum diethylphosphinate flame-retarded polyamide 6.6 were investigated. All smoke suppressants improve the protective layer and act as an adjuvant. Silica and melem performed best under forced flaming conditions. Spherical silica reduces the peak of heat release rate by 39% and the total heat evolved by 14%, whereas 10 wt% melem lowers the total smoke production by 41%. Melem alters the mode of action of aluminum diethylphosphinate from gas to more condensed phase activity. This change reduces flame inhibition and hence smoke toxicity, but further improves the protective layer due to charring reactions in the decomposition mechanism. In addition, the sizes of the smoke particles decrease because of the prolonged time in the pyrolytic zone. This study highlights that interactions between polymer, flame retardants, and smoke suppressants can significantly determine the smoking and burning behavior. KW - Smoke suppressant KW - Flame retardancy KW - Aluminum diethylphosphinate KW - Smoke KW - Polyamide 6.6 PY - 2024 DO - https://doi.org/10.1177/07349041231220250 SN - 0734-9041 VL - 42 IS - 2 SP - 117 EP - 141 PB - SAGE Publications AN - OPUS4-59533 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goller, Sebastian M. A1 - Krüger, Simone A1 - Schartel, Bernhard T1 - No business as usual: The effect of smoke suppressants commonly used in the flame retardant PA6.6 on smoke and fire properties N2 - As most of polymeric materials are inherently flammable, flame retardants (FR) are commonly used to reduce their fire risks. Nevertheless, these flame retardant materials are often detrimental to smoke parameters like specific optical density or smoke toxicity. The influence of several smoke suppressants (SP)-zinc stannate, zinc phosphate, titanium oxide and hydrotalcite-were investigated with respect to flame retardancy, smoke emission, particle emission and smoke toxicity in a diethyl aluminum phosphinate (AlPi) flame retardant polyamide 6.6 (PA6.6). It was shown that the interaction between SP, FR and polymer is crucial for smoke and fire properties and can change the mode of action of the FR as well the decomposition mechanism of the polymer. Small amounts of SP show less effect on forced flaming behavior and the optical density, but they can influence flammability and the particle size distribution of the soot particles. The flame retardancy was significantly enhanced by 5 wt.-% zinc stannate in PA6.6 under forced flaming conditions. The charring mechanism was improved, and the mode of action of AlPi switched from the gas to the condensed phase. This resulted of in a reduced PHRR and TSP and an increase in residue yield. The smoke toxicity and optical density were reduced in the smoke density chamber as well. The smoke particles shifted to smaller sizes as the time in the pyrolytic zone increased. The formation of a dense char is assumed to be the key factor to enhance smoke suppression and flame retardancy properties. KW - Polyamide 6.6 KW - Smoke suppression KW - Flame retardancy KW - Zinc stannate KW - Smoke density PY - 2023 DO - https://doi.org/10.1016/j.polymdegradstab.2023.110276 SN - 0141-3910 VL - 209 PB - Elsevier Ltd. AN - OPUS4-56981 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Goller, Sebastian M. A1 - Schartel, Bernhard A1 - Krüger, Simone T1 - Phosphorus features halogen –calcium hypophosphite replaces antimony trioxide, reduces smoke, and improves flame retardancy N2 - Replacing antimony trioxide (ATO) in flame retardant formulations is an urgent task due to its toxicity. There are indications that calcium hypophosphite (CaP) may be a promising replacement. This study investigates the decomposition, fire behavior, and smoke release of brominated flame-retarded acrylonitrile butadiene styrene (ABS) under various fire scenarios like ignition, developing fire and smoldering, while replacing ATO with CaP and CaP/talc. Adding 4 wt.-% of talc to CaP formulations showed beneficial effects on flammability due to changes in the viscosity and barrier properties. Synergism between 8 wt.-% talc and CaP improved the protective layer in the developing fire scenario, resulting in a ∼60 % decrease in the peak of heat release rate and reduction of ∼21 % in total smoke production (ref. ABS+Br+ATO). With a conventional index of toxicity (CIT) of below 0.75, ABS+Br+CaP passes the highest requirements according to EN 45545-2. Overall, the CaP/talc materials improve flame retardancy, show less smoke emission under forced flaming conditions, and prevent chronic intoxication and environmental pollution through smoke particles contaminated with antimony. KW - Smoke KW - Flame retardancy KW - Acrylonitrile butadiene styrene KW - Calcium hypophosphite KW - Antimony trioxide PY - 2024 DO - https://doi.org/10.1016/j.tca.2024.179764 SN - 0040-6031 VL - 737 SP - 1 EP - 9 PB - Elsevier Ltd. AN - OPUS4-60063 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Krüger, Simone A1 - Stoll, S. A1 - Roider, G. A1 - Kraus, S. A1 - Keil, W. T1 - Hydrogen cyanide in fire tests Forensic aspects N2 - The inhalationof smoke gases is awell-established cause of poisoning and leads to the death of fire victims. Carbonmonoxide(CO) and Hydrogen cyanide (HCN) are two of the main noxious gases,whereby HCN is formed by an incomplete combustion of materials containing nitrogen. These materials may be natural materials, such as wool, silk and feathers or synthetic plastics, such as polyacrylonitrile (PAN), polyamide and polyurethane. These materials are very common in modern household furnishings; therefore, notonlyCObutalsoHCN can be produced during home fires. Up tonowonly a fewstudieshave been carried out on the generation of HCN as the fire proceeds, e. g. by Crewe et al. The data from such analyses are useful for forensic purposes. This enables the possibility to more accurately assess the events at the fire location, the Situation in which the fire victims are found as well as the cause of death. One way to analyze the gas composition of smoke is to perform bench scale fire tests, where various fire scenarios can be simulated on a smaller scale (e. g. using a smoke density chamber). The results from such experiments were compared with the results obtained in an enclosed room fire test. KW - Fire test KW - Hydrogen cyanide KW - Forensic KW - Carbon monoxide KW - Smoke inhalation injury KW - Polyurethane KW - Fires KW - Toxicity PY - 2016 DO - https://doi.org/10.1007/s00194-016-0090-5 SN - 0937-9819 VL - 26 IS - 3 SP - 184 EP - 188 PB - Springer Verlag CY - New York, NY, USA AN - OPUS4-36671 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pötzsch, Sina A1 - Timme, Sebastian A1 - Sklorz, Christian A1 - Skoczowsky, Danilo A1 - Otremba, Frank A1 - Krüger, Simone T1 - Fire protection systems for tanks made of GFRP N2 - The application of lightweight materials for tanks for transportation appears promising. Besides saving weight and therefore transportation costs, new complex geometries that depart from common cylindrical shapes of steel tanks can be manufactured. For transportation of dangerous goods, fire and explosion safety must be maintained to prevent accidents with serious consequences. In this work the fire behavior of lightweight tanks made from glass fiber reinforced plastics (GFRP) with complex geometries is investigated. Pretests on intermediate scale GFRP plates are conducted to identify suitable fire protection systems and surface treatments for composite tanks. The fire resistance is shown to be improved by addition of fire protective coatings and integrated layers. Finally, a complex rectangular GFRP tank with a holding capacity of 1100 liters is fire protected with an intumescent fire coating. The tank is filled up to 80 % with water and burned under an engulfing fully developed fire. It was shown that the intumescent layer could expand before the decomposition of the resin occurred. Furthermore, the adhesion between tank surface and coating was maintained. The structure could withstand a fire for more than 20 min. T2 - ASME International Mechanical Engineering Congress and Exposition (IMECE) 2017 CY - Tampa, Florida, USA DA - 03.11.2017 KW - Lightweight tank KW - Composites in fire KW - GFRP KW - Fire retardants KW - Intumescent layer PY - 2017 SN - 978-0-7918-5849-3 VL - 14 SP - Article UNSP V014T14A017, 1 EP - 6 PB - ASME Press AN - OPUS4-42991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Farag, Zeinab A1 - Moustapha, M. A1 - Hidde, Gundula A1 - Friedrich, Jörg A1 - Azzam, M. A1 - Krüger, Simone ED - Mital, K.L. T1 - Promotion of Adhesion of Green Flame Retardant Coatings onto Polyolefins by Depositing Ultra-Thin Plasma Polymer Films N2 - Various methods have been used for introducing fire retardant additives into polymers. Deposition of thick fire retardant coatings directly onto polymer substrates is an alternative technique. An important advantage of the coating technique is the preservation of the physical and chemical integrity of the polymer material. Moreover, the fire retardancy of the polymer materials can be achieved following their production. Suitable coating materials are inorganics, intumescent, char-forming, oxygendiluting, and cooling or radical quenching layers. The most important problem is to achieve sufficient coating thickness to withstand the direct attack of flame and to protect the polymer bulk from pyrolysis, otherwise blistering of coating, caused by emitted pyrolysis gases, is often observed. To avoid blistering of coating, the adhesion between polyolefin substrate and fire retardant coating has to be extraordinarily high. In order to achieve such a high level of adhesion, the polymer surface has to be modified with adhesion-promoting functional groups. The deposition of thin plasma polymers as adhesion-promoting layers with NH2, OH or COOH groups has been the most suited method. These functional groups are able to form covalent bonds and other interactions between the fire-resistant coating and the plasma-modified polyolefin substrate. Additionally, the plasma polymer counteracts the strong mechanical stresses in the laminate on exposure to high temperatures by its flexibility. KW - Plasma KW - Adhesion PY - 2017 SN - 978-1-119-40748-5 SN - 978-1-119-40638-9 DO - https://doi.org/10.1002/9781119407485 VL - 2 SP - 399 EP - 427 PB - Scrivener Publishing CY - Beverly, USA AN - OPUS4-47227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pötzsch, Sina A1 - Krüger, Simone A1 - Sklorz, Christian A1 - Borch, Jörg A1 - Hilse, Thilo A1 - Otremba, Frank T1 - The fire resistance of lightweight composite tanks depending on fire protection systems N2 - To save weight and resources lightweight tanks with complex geometries made of glass-fibre reinforced plastics (GFRP) are a promising innovation for the transportation of dangerous goods. To realise the use of polymer tanks for such applications, their fire safety must be guaranteed. This paper presents solutions to protect fibre-reinforced plastic tanks from fire. The fire resistance of six GFRP tanks with different fire protection systems was tested in an outdoor full-scale fire test facility according to the regulation stipulated in the ADR (European agreement concerning the national carriage of dangerous goods by road). All tanks feature a complex geometry and a holding capacity of 1100 litres. The fire protection systems are composed of specialised resins as well as two intumescent coatings. All systems had a protective impact. The best results were achieved by the epoxy based intumescent coating, which was able to prolong the time needed to reach 150 °C inside the tank by 20 min. The emergence of a temperature holding point inside the tank due to condensation effects was observed at temperatures around 100 °C. KW - Fire safety composite tanks PY - 2018 UR - https://www.sciencedirect.com/science/article/pii/S0379711218301644 DO - https://doi.org/10.1016/j.firesaf.2018.08.007 SN - 0379-7112 SN - 1873-7226 VL - 100 SP - 118 EP - 127 PB - Elsevier Ltd. AN - OPUS4-45697 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Legall, Herbert A1 - Schwanke, Christoph A1 - Pentzien, Simone A1 - Dittmar, G. A1 - Bonse, Jörn A1 - Krüger, Jörg T1 - X-ray emission as a potential hazard during ultrashort pulse laser material processing N2 - In laser machining with ultrashort laser pulses unwanted X-ray radiation in the keV range can be generated when a critical laser intensity is exceeded. Even if the emitted X-ray dose per pulse is low, high laser repetition rates can lead to an accumulation of X-ray doses beyond exposure safety limits. For 925 fs pulse duration at a center wavelength of 1030 nm, the X-ray emission was investigated up to an intensity of 2.6 × 10^14 W/cm2. The experiments were performed in air with a thin disk laser at a repetition rate of 400 kHz. X-ray spectra and doses were measured for various planar target materials covering a wide range of the periodic table from aluminum to tungsten. Without radiation shielding, the measured radiation doses at this high repetition rate clearly exceed the regulatory limits. Estimations for an adequate radiation shielding are provided. KW - Laser-induced X-ray emission KW - Ultrashort laser material interaction KW - Femtosecond laser KW - Radiation protection PY - 2018 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-448431 DO - https://doi.org/10.1007/s00339-018-1828-6 SN - 0947-8396 SN - 1432-0630 VL - 124 IS - 6 SP - Article 407, 1 EP - 8 PB - Springer AN - OPUS4-44843 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rappsilber, Tim A1 - Krüger, Simone T1 - Design fires with mixed-material burning cribs to determine the extinguishing effects of compressed air foams N2 - This study evaluates the efficacy of compressed air foam (CAF) in comparison to common fire extinguishing media. Newly developed mixed-material burning cribs were used as a normative fire load for extinguishing tests to accurately represent the significantly elevated utilization of synthetic materials in everyday life. A series of outdoor experiments was carried out to analyze the effectiveness of the fire extinguishing medium CAF using synthetical class-A foaming agents from two different manufacturers, and compared them to water and waterfoam solution as a function of the extinguishing distance. In a second series, performed inside a fire room, the efficiency of CAF-usage in indoor fires was evaluated. Moreover, the results of the indoor test series provided information about the composition of smoke gases based on the kind of extinguishing tactic used to suppress the fire. The results showed that under the tested conditions CAF suppressed fire more effectively than both water and water with foaming agents. CAF was able to wet areas hardly accessible to other extinguishing media, and due to its various simultaneously occurring effects and its compact jet with high kinetic energy, it cooled down temperatures more efficiently than water or water-foam solution. KW - Crib KW - Compressed Air Foam KW - Design fire KW - Extinguish KW - Fire test PY - 2018 DO - https://doi.org/10.1016/j.firesaf.2018.03.004 SN - 0379-7112 SN - 1873-7226 VL - 98 SP - 3 EP - 14 PB - Elsevier Ltd. AN - OPUS4-44632 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schmidt, Birgit Angelika A1 - Pentzien, Simone A1 - Conradi, Andrea A1 - Krüger, Jörg T1 - Femtosecond and nanosecond laser decontaminations of biocidal-loaded wooden artworks N2 - Until the end of the 1980s many wooden artworks underwent surface treatment by liquid preservatives, e.g. Hylotox-59. DDT (dichlorodiphenyltrichloroethane) crystal structures are formed on the wooden surfaces by the "blooming" of chlorine compounds by time. In addition to an aesthetic disturbance, it is assumed that DDT represents a health risk. Therefore, the removal of DDT crystals from the surfaces is requested. Contaminated wood with natural biocide ageing, gilded and wood carved elements and wooden samples with paint layers were provided by the Schlossmuseum Sondershausen, Germany. Laser cleaning on selected surface areas on the objects was done by means of femtosecond and nanosecond laser pulses. For the same object, cleaning results using 30-fs laser pulses at 800 nm wavelength are compared to findings utilizing 10-ns laser pulses at 1064 nm wavelength. Before and after laser treatment, chlorine measurements at the same surface position were done by X-ray fluorescence analysis (XRF) as an indicator for the presence of DDT. In this way, pointwise chlorine depletion rates can be obtained for the different pulse duration regimes and wavelengths. Additionally, the object surfaces were examined using optical microscopy and multi spectral imaging analysis. T2 - EMRS Spring Meeting 2017, Symposium X “New frontiers in laser interaction: from hard coatings to smart materials" CY - Strasbourg, France DA - 22.05.2017 KW - Laser cleaning KW - Decontamination KW - Wood KW - DDT KW - Femtosecond laser PY - 2017 DO - https://doi.org/10.1007/s00339-017-1316-4 SN - 0947-8396 SN - 1432-0630 VL - 123 IS - 11 SP - Article 696, 1 EP - 9 PB - Springer AN - OPUS4-42564 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Häßler, Dustin A1 - Häßler, Mai A1 - Hothan, Sascha A1 - Krüger, Simone T1 - Leistungsfähigkeit reaktiver Brandschutzsysteme auf Zugstabsystemen und deren Anschlusskonstruktionen T1 - Performance of intumescent fire protection coatings on steel tension rod systems and their complex connection components N2 - Zur brandschutztechnischen Ertüchtigung von Stahlkonstruktionen werden reaktive Brandschutzsysteme aufgrund der geringen Beschichtungsdicken und der profilfolgenden Applikation in zunehmendem Maße eingesetzt. Da die für Zugstabsysteme eingesetzten Bauteile meist eine stark konvex gekrümmte Oberfläche aufweisen und der Anschlussbereich über eine vergleichsweise komplexe Geometrie verfügt, stellt dies besonders hohe Anforderungen an die Leistungsfähigkeit von reaktiven Brandschutzsystemen. Anhand von realmaßstäblichen Brandversuchen wurden das Aufschäumungs- und Rissverhalten, der Einfluss der Trockenschichtdicke, die Erwärmung der einzelnen Stahlbauteile sowie der Einfluss der Bauteilorientierung untersucht. Die Ergebnisse zeigen, dass eine Abnahme der Oberflächenkrümmung oder eine Erhöhung der Massenkonzentration der Stahlbauteile zu einer geringeren Aufheizrate des Stahls führt. Darüber hinaus ist festzustellen, dass die Leistungsfähigkeit des reaktiven Brandschutzsystems von der Bauteilorientierung der Zugstabsysteme beeinflusst wird. Die durchgeführten Brandversuche können zur Entwicklung geeigneter Prüfszenarien für die Beurteilung von reaktiven Brandschutzsystemen auf Zugstabsystemen und deren Anschlusskonstruktionen verwendet werden, wodurch eine Erweiterung des zulassungsbasierten Anwendungsbereichs ermöglicht wird. KW - Stahl KW - Brandschutz KW - Brandversuche KW - Zugstabsystem KW - Reaktives Brandschutzsystem PY - 2018 DO - https://doi.org/10.1002/stab.201800014 SN - 0038-9145 SN - 1437-1049 VL - 87 IS - 11 SP - 1049 EP - 1056 PB - Ernst & Sohn CY - Berlin AN - OPUS4-46565 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mohamed, Zeinab A1 - Friedrich, Jörg Florian A1 - Krüger, Simone A1 - Farouk, M. A1 - Moustapha, M.E. T1 - Plasma deposition of adhesion-promoting polymer layers onto polypropylene for subsequent covering with thick fire retardant coatings N2 - Melamine resins were used as 50-µm-thick fire retardant coatings for polypropylene (PP). Preceding deposition, low-pressure plasma polymer films of allyl alcohol were coated onto PP to improve the adhesion between PP and melamine resin coatings. The efficiency of such fire retardant coatings was confirmed by flame tests. The plasma-deposited polymer and the dip-coated melamine resin films were characterized by Fourier transform infrared-attenuated total reflectance spectroscopy and X-ray photoelectron spectroscopy (XPS). The adhesion of coatings was measured using a 90° peel test with a doubled-faced adhesive tape. To detect the locus of failure, the peeled layer surfaces were inspected using optical microscopy and XPS. Thermal properties of PP thick melamine resin-coated films were analyzed by thermogravimetric analysis. KW - Polymer KW - Plasma KW - Polypropylene KW - Fire retardant KW - Melamine precursors KW - Plasma polymerization KW - Allyl alcohol KW - Flame retardants KW - Curing PY - 2015 DO - https://doi.org/10.1080/01694243.2015.1033878 SN - 0169-4243 SN - 1568-5616 VL - 29 IS - 14 SP - 1522 EP - 1533 PB - VNU Science Press CY - Utrecht AN - OPUS4-33112 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krüger, Simone A1 - Despinasse, Marie-Claire A1 - Stahn, Sebastian A1 - Raspe, Tina A1 - Nörthemann, K. A1 - Moritz, W. T1 - Freisetzung toxischer Gase bei der Verwendung von Grillgeräten in geschlossenen Räumen und deren frühzeitige Detektion N2 - Durch die Verwendung von Grillgeräten in geschlossenen Räumen, wie Gartenlauben, Wohnungen oder Garagen kam es in den vergangenen Jahren zu einer Vielzahl von Unfällen mit schweren Vergiftungen und Todesfällen. Seit 2008 scheint das Auftreten von Kohlenmonoxid (CO) Intoxikationen innerhalb Deutschland wieder zu zunehmen. Die Hauptursachen sind dabei der unsachgemäße Gebrauch von Holzkohlegrills, schlecht gewartete Gasthermen und Kamine. Zum Schutz der Bevölkerung ist deshalb eine Aufklärung über mögliche Gefahren wichtig. Im Rahmen dieser Arbeit wurden diese Gefahren bewertet. Es wurden verschiedene Brandszenarien mit Grillgeräten, mit unterschiedlichen Grillkohlearten und –mengen in geschlossenen Räumen realisiert und die entsprechenden Konzentrations-Zeit-Verläufe ermittelt. Bei den Brandversuchen wurden zudem notwendige Eingabeparameter für numerische Simulationen ermittelt, um die Verwendung von Holzkohlegrills in geschlossenen Räumen zu simulieren. Die Auswirkungen für Menschen beim Grillen in geschlossenen Räumen wurden quantifiziert, indem die Eintrittszeitpunkte der Handlungsunfähigkeit und des Todes mittels Fractional Effective Dose (FED)-Konzept bestimmt wurden. Die Ergebnisse zeigen deutlich, dass eine frühzeitige Detektion der toxischen Gase zur Warnung von Personen dringend notwendig ist. In den durchgeführten Brandversuchen zeigte sich, dass die gebräuchlichen Rauchmelder auf Streulichtbasis keine rechtzeitige Warnung ermöglichen. Deshalb sind für solche Brandszenarien andere Branddetektoren erforderlich. Entsprechende Versuche mit CO-Brandmeldern zeigten, dass das freigesetzte CO beim Grillen in geschlossenen Räumen frühzeitig detektiert werden kann und Personen somit rechtzeitig gewarnt werden können. Zur frühzeitigen Erkennung von Schwelbränden wurde weiterhin ein neuer Wasserstoffdetektor getestet. Die Entstehung von Wasserstoff in einer sehr frühen Brandphase kann zur frühzeitigen Erkennung von Schwelbränden genutzt werden. Bei ersten Schwelbrandexperimenten mit Holzproben konnte Wasserstoff in einer geschlossenen Kammer (0,5 m3) nachgewiesen werden, noch bevor es zu einer erhöhten CO-Emission kam. Die Ergebnisse der Schwelbrandversuche werden vorgestellt und die Verwendbarkeit von CO- und Wasserstoff-Detektoren erörtert und diskutiert. T2 - 4. Magdeburger Brand- und Explosionsschutztag / 3. vfdb-Workshop Brandschutzforschung CY - Magdeburg, Germany DA - 26.03.2015 KW - Toxizität KW - FED KW - Brandmelder KW - Brandfrüherkennung KW - Rauchgase KW - Kohlenmonoxid KW - Grillen PY - 2015 SN - 978-3-00-048960-0 SP - 1 EP - 13 AN - OPUS4-33188 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mohamed, Zeinab A1 - Friedrich, Jörg Florian A1 - Krüger, Simone T1 - Cured melamine systems as thick fire-retardant layers deposited by combination of plasma technology and dip-coating N2 - Melamine and melamine resins are widely used as fire-retardants for polymer building materials. Cured melamine systems are used in heat-sensitive items, such as furniture and window frames and sills. In this work, differently cured methylated poly(melamine-co-formaldehyde) (cmPMF) resins were used as fire-retardant coverage for poly(styrene) (PS) and poly(ethylene) (PE) building materials. Such polymer layers should have several tenths of micrometers thickness to produce sufficient fire retardancy. These thick layers were produced by dip-coating. To promote sufficient adhesion of such thick coating to the polyolefin substrates, also in the case of high temperatures occurring at fire exposure, the polymer substrates were firstly coated with a few hundred nanometer thick adhesion-promoting plasma polymer layer. Such thin plasma polymer layers were deposited by low-pressure plasma polymerization of allyl alcohol (ppAAl). It was assumed that the hydroxyl groups of ppAAl interact with the melamine resin; therefore, ppAAl was well suited as adhesion promoter for thick melamine resin coatings. Chemical structure and composition of polymer films were investigated using infrared-attenuated total reflectance and X-ray photoelectron spectroscopy (XPS). Peel strengths of coatings were measured. After peeling, the peeled polymer surfaces were also investigated using optical microscopy and XPS the layers for identification of the locus of peel front propagation. Thermal properties were analyzed using TGA (thermo-gravimetric analyses). Finally, the fire-retardant properties of such thick coated polymers were evaluated by exposure to flames. KW - Plasma polymerization KW - Dip-coating KW - Curing KW - Methylated poly(melamine-co-formaldehyde) KW - Polystyrene KW - Polyethylene KW - Flame retardancy KW - Polymer KW - Plasma KW - Melamine resin KW - Fire retardant PY - 2015 DO - https://doi.org/10.1080/01694243.2014.995911 SN - 0169-4243 SN - 1568-5616 VL - 29 IS - 9 SP - 807 EP - 820 PB - VNU Science Press CY - Utrecht AN - OPUS4-32795 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -