TY - JOUR A1 - Gallo, Emanuela A1 - Sánchez-Olivares, G. A1 - Schartel, Bernhard T1 - Flame retardancy of starch-based biocomposites - aluminium hydroxide-coconut fiber synergy N2 - The use of coconut fiber (CF) agricultural waste was considered as an environmentally friendly and inexpensive alternative in flame retarded biocomposites. To decrease the high content of aluminum trihydrate (ATH) required, the thermal decomposition (thermogravimetry), flammability [oxygen index (LOI) and UL 94 test] and fire behavior (cone calorimeter) of a combination of CF and ATH were investigated in a commercial blend of thermoplastic starch (TPS) and cellulose derivatives. CF induced some charring activity, slightly decreasing the fire load and burning propensity in cone calorimeter test. ATH decomposes endothermically into water and inorganic residue. Significant fuel dilution as well as a pronounced residual protection layer reduces the fire hazards. Replacing a part of ATH with coconut fibers resulted in improved flame retardancy in terms of ignition, reaction to small flame, and flame-spread characteristics [heat release rate (HRR), fire growth rate (FIGRA), etc.]. The observed ATH and CF synergy opens the door to significant reduction of the ATH contents and thus to interesting flame retarded biocomposites. KW - Biocomposites KW - Flammability KW - Starch KW - Aluminium hydroxide KW - Coconut fiber PY - 2013 SN - 0032-2725 VL - 58 IS - 5 SP - 395 EP - 402 PB - Industrial chemistry research inst CY - Warszawa, Poland AN - OPUS4-28513 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Braun, Ulrike A1 - Russo, P. A1 - Acierno, Domenico T1 - Fire retardant synergisms between nanometric Fe2O3 and aluminium phosphinate in poly(butylene terephthalate) N2 - The pyrolysis and the flame retardancy of poly(butylene terephthalate) (PBT) containing aluminum diethylphosphinate (AlPi) and nanometric Fe2O3 were investigated using thermal analysis, evolved gas analysis (Thermogravimetry-FTIR), flammability tests (LOI, UL 94), cone calorimeter measurements and chemical analysis of residue (FTIR). AlPi mainly acts as a flame inhibitor in the gas phase, through the release of diethylphosphinic acid. A small amount of Fe2O3 in PBT promotes the formation of a carbonaceous char in the condensed phase. The combination of 5 and 8 wt% AlPi, respectively, with 2 wt% metal oxides achieves V-0 classification in the UL 94 test thanks to complementary action mechanisms. Using PBT/metal oxide nanocomposites shows a significant increase in the flame retardancy efficiency of AlPi in PBT and thus opens the route to surprisingly sufficient additive contents as low as 7 wt%. KW - Poly(butylene terephthalate) (PBT) KW - Flammability KW - Metal oxide KW - Nanocomposite KW - Aluminum diethylphosphinate PY - 2011 U6 - https://doi.org/10.1002/pat.1774 SN - 1042-7147 SN - 1099-1581 VL - 22 IS - 12 SP - 2382 EP - 2391 PB - John Wiley & Sons, Ltd. CY - Chichester AN - OPUS4-24915 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Schmaucks, G. A1 - von der Ehe, Kerstin A1 - Böhning, Martin T1 - Effect of well dispersed amorphous silicon dioxide in flame retarded styrene butadiene rubber N2 - Spherically shaped amorphous silicon dioxide with broad size particle distribution was used in combination with aluminium trihydroxide (ATH) in styrene butadiene rubber composites. The pyrolysis, flammability, fire properties, flame spread and gas diffusion were investigated. The kind and amount of ATH, but in particular the fine silicon dioxide chosen as an additive, influenced the thermal decomposition and fire behaviour of styrene butadiene rubber composites. Gravimetric gas sorption measurements showed that the gas diffusion was systematically lower with silicon dioxide. The initial pyrolysis gas release was hindered, increasing the temperature at which decomposition begins as well as the ignition time in fire tests. During combustion, ATH and silicon dioxide accumulate on the surface of the specimen, forming a residual protective layer. A reduced peak heat release rate and fire spread were observed. The addition of a special kind of silicon dioxide is proposed to play a key role in optimising fire retardancy. KW - Flame retardancy KW - Styrene butadiene rubber KW - SBR KW - Silicon dioxide KW - Aluminium trihydroxide KW - ATH PY - 2013 U6 - https://doi.org/10.1179/1743289812Y.0000000012 SN - 1465-8011 SN - 1743-2898 VL - 42 IS - 1 SP - 34 EP - 42 PB - IOM Communications CY - London, UK AN - OPUS4-27626 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lorenzetti, A. A1 - Besco, S. A1 - Hrelja, D. A1 - Roso, M. A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Modesti, M. T1 - Phosphinates and layered silicates in charring polymers: The flame retardancy action in polyurethane foams N2 - Nanocomposites of a charring polymer (like polyurethane foam) filled with aluminum phosphinate (AlPi) with or without melamine cyanurate (MelCy) have been prepared by microwave processing and their thermal stability and fire behavior have been studied. Results on the interaction between flame retardants and layered silicates were provided as well as detailed investigation of the char strength, which has been carried out using a suitably developed method based on dynamic-mechanic analysis. Generally, the thermo-oxidative stability in presence of layered silicates was higher than the counterparts even if an additive rather than synergic effect took place; however, in some cases the interaction between clays and phosphinate led to a significant decrease of weight residue. In nitrogen the residue amounts were about the same but a higher amount of phosphorus was retained in the solid phase in presence of clays. Cone calorimeter results showed that the use of phosphinates led to a decrease of the PHRR; further addition of clays did not reduce the PHRR owing to the worse quality of char layer as demonstrated by the char strength test. However, it has been shown that the partial substitution of aluminum phosphinate with melamine cyanurate gave improved results: the AlPi–MelCy filled foams showed similar pHRR and THE but lower TSR and higher char strength than AlPi filled foams. It was also confirmed that phosphinate acted by flame inhibition but its action was depressed by the use of nanoclays owing to their interaction. KW - Phosphinate KW - Nanocomposite KW - Polyurethane KW - Interaction KW - Flame retardant PY - 2013 U6 - https://doi.org/10.1016/j.polymdegradstab.2013.08.002 SN - 0141-3910 SN - 1873-2321 VL - 98 IS - 11 SP - 2366 EP - 2374 PB - Applied Science Publ. CY - London AN - OPUS4-29281 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Braun, Ulrike A1 - Russo, P. A1 - Acierno, Domenico T1 - Synergistic flame retardant halogen-free combination of aluminium phosphinate and metal oxides in PBT T2 - Interflam 2010 - 12th International conference CY - Nottingham, UK DA - 2010-07-05 KW - Poly(butylene terephthalate) KW - Metal oxide KW - Phosphinate KW - Flammability PY - 2010 SN - 978-0-9541216-5-5 VL - 1 SP - 629 EP - 640 PB - Interscience Communications CY - London, UK AN - OPUS4-21669 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Acierno, Domenico A1 - Cimino, F. A1 - Russo, P. T1 - Tailoring the flame retardant and mechanical performances of natural fiber-reinforced biopolymer by multi-component laminate N2 - The potential of a multi-component laminate composite material in terms of improved flame retardancy and adequate mechanical performance is discussed. A double-layer system based on a biodegradable polyhydroxyalkanoates blend was obtained by compression molding. A thin halogen-free flame-retarded layer was located at the top of a kenaf-fiber-reinforced core. Kenaf fibers acted as a carbonization compound promoting charring and building up a superficial insulating layer that protected the material throughout combustion. The impact of different skin/core thickness on the thermal and fire properties was investigated. Synergistic flame retardancy occurs in the cone calorimeter. Chemical and fire investigations confirmed a changed pyrolysis behavior in multicomponent materials. Promising results are obtained in terms of mechanical performance: higher flexural and impact properties were observed in the single fiber-reinforced layer. KW - A. Fibres KW - A. Layered structures KW - D. Thermal analysis KW - D. Mechanical testing PY - 2013 U6 - https://doi.org/10.1016/j.compositesb.2012.07.005 SN - 1359-8368 VL - 44 IS - 1 SP - 112 EP - 119 PB - Elsevier CY - Oxford [u.a.] AN - OPUS4-26741 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lorenzetti, A. A1 - Modesti, M. A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Besco, S. A1 - Roso, M. T1 - Synthesis of phosphinated polyurethane foams with improved fire behaviour N2 - Both alkylphosphinates and inorganic phosphinates (based on sodium, calcium, magnesium or zinc) have been recently proposed as flame retardants for polyesters, polyamides and polyurethane foams as well. The main aim of this work was to compare the flame retardant effectiveness of inorganic (already proofed in PU foams) and organic phosphinates in PU foams which have never been used in polyurethane (PU) foams. The thermal stability in nitrogen and air as well as limiting oxygen index and cone calorimeter behaviour have been studied to assess the effectiveness of such flame retardants in PU foams. The results obtained showed that both inorganic and organic phosphinates are effective in enhancing fire behaviour of PU foams since they improve thermal stability, LOI and fire performance. Cone calorimetry highlighted the flame inhibition action in the gas phase due to the release of phosphorus-containing molecules. The better results obtained for inorganic phosphinate are probably related to the better quality of the char layer developed during burning, but may also be related to the higher phosphorus content of such flame retardant with respect the other ones. It was also verified that both inorganic and organic phosphinate containing N-synergic compound showed a fuel dilution effect, deriving from water and/or ammonia release in the gas phase. KW - Phosphinate KW - Polyurethane foam KW - Flame retardancy KW - Fire behaviour PY - 2012 U6 - https://doi.org/10.1016/j.polymdegradstab.2012.07.026 SN - 0141-3910 SN - 1873-2321 VL - 97 IS - 11 SP - 2364 EP - 2369 PB - Applied Science Publ. CY - London AN - OPUS4-26735 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bier, A.K. A1 - Bognitzki, M. A1 - Schmidt, A. A1 - Greiner, A. A1 - Gallo, Emanuela A1 - Klack, Patrick A1 - Schartel, Bernhard T1 - Synthesis, properties, and processing of new siloxane-substituted poly(p-xylylene) via CVD N2 - The synthesis of a disiloxane-functionalized [2.2]paracyclophane and its polymerization to the corresponding siloxane-substituted poly(p-xylylene) via chemical vapor deposition (CVD) has been described. Because of the enhanced solubility of the siloxane substituted poly(p-xylylene) analysis of the molecular structure by NMR, molecular weight, and polydispersity by gel permeation chromatography (GPC), and processing by film casting as well as nanofiber formation by electrospinning was possible. Structural isomers were found by NMR which was expected due to the isomeric mixture of the precursor. High molecular weights at moderate polydispersities were found by GPC which was unexpected for a vapor phase deposition polymerization. The amorphous morphology in combination with a low glass transition temperature led to high elongation at break for the siloxane substituted poly(p-xylylene). Significant difference for the wetting versus water was found for as-deposited films, solution cast films, and nanofibers obtained by electrospinning with contact angles up to 135° close to superhydrophobic behavior. KW - Poly(p-xylylene) KW - Siloxane functionalized PPX KW - Chemical vapor deposition KW - Difunctionalized [2.2]paracyclophanes KW - Gorham process PY - 2012 U6 - https://doi.org/10.1021/ma2021369 SN - 0024-9297 SN - 1520-5835 VL - 45 IS - 2 SP - 633 EP - 639 PB - American Chemical Society CY - Washington, DC AN - OPUS4-25466 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Schartel, Bernhard A1 - Acierno, Domenico A1 - Russo, P. T1 - Flame retardant biocomposites: Synergism between phosphinate and nanometric metal oxides N2 - The known flame-retardant synergism between phosphorus-based additives and metal oxides, already used for petroleum-based plastics, has been extended to bio-based materials. The pyrolysis and the flame-retardancy properties of aluminium phosphinate (AlPi) in combination with nanometric iron oxide and antimony oxide on a poly(3-hydroxy-butyrate-co-3-hydroxyvalerate)/poly(butylene adipate-co-terephthalate) (PHBV/PBAT) blend were investigated. Better fire retardancy, ascribed to increases in intermediate char, favoured improvements in the UL 94 classification. Both the phosphorus and the nanofiller components participate simultaneously in the flame-retardancy mechanism: the first acting as flame inhibition in the gas phase, and the second promoting cross-linking in the solid phase. Redox reactions between iron oxide and the phosphinate additive were confirmed by XRD analysis and provided further evidence of the activity of metal compounds. KW - Aliphatic biopolyesters KW - Metal oxide KW - Flame retardancy KW - Aluminium phosphinate PY - 2011 U6 - https://doi.org/10.1016/j.eurpolymj.2011.04.001 SN - 0014-3057 SN - 1873-1945 VL - 47 IS - 7 SP - 1390 EP - 1401 PB - Elsevier CY - Oxford AN - OPUS4-23889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Fan, Z. A1 - Schartel, Bernhard A1 - Greiner, A. T1 - Electrospun nanofiber mats coating - new route to flame retardancy N2 - A novel route toward halogen-free fire retardancy of polymers through innovative surface coating is described. Nanofiber mats based on polyimide are deposited on PA66 through electrospinning. Scanning electron microscopy is used to characterize the nanofibers. Cone calorimeter tests were performed to evaluate the fire performance. Because of their low thermal conductivity, electrospun nanofiber mats act not only as sacrificial layers but also as a protective surface that delays ignition. The effect is influenced by the fiber diameters and the imidization. KW - Electrospinning KW - Polyimide KW - Nanofibers KW - Fire retardancy PY - 2011 U6 - https://doi.org/10.1002/pat.1994 SN - 1042-7147 SN - 1099-1581 VL - 22 IS - 7 SP - 1205 EP - 1210 PB - John Wiley & Sons, Ltd. CY - Chichester AN - OPUS4-24093 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Braun, Ulrike A1 - Schartel, Bernhard A1 - Russo, P. A1 - Acierno, Domenico T1 - Halogen-free flame retarded poly(butylene terephthalate) (PBT) using metal oxides/PBT nanocomposites in combination with aluminium phosphinate N2 - The flame retardancy of poly(butylene terephthalate) (PBT) containing aluminium diethlyphosphinate (AlPi) and/or nanometric metal oxides such as TiO2 or Al2O3 was investigated. In particular the different active flame retardancy mechanisms were discovered. Thermal analysis, evolved gas analysis (TG-FTIR), flammability tests (LOI, UL 94), cone calorimeter measurements and chemical analyses of residues (ATR-FTIR) were used. AlPi acts mainly in the gas phase through the release of diethylphosphic acid, which provides flame inhibition. Part of AlPi remains in the solid phase reacting with the PBT to phosphinate-terephthalate salts that decompose to aluminium phosphate at higher temperatures. The metal oxides interact with the PBT decomposition and promote the formation of additional stable carbonaceous char in the condensed phase. A combination of metal oxides and AlPi gains the better classification in the UL 94 test thanks to the combination of the different mechanisms. KW - Poly(butylene terephthalate) KW - Flammability KW - Metal oxide nanocomposite KW - Metal phosphinate PY - 2009 U6 - https://doi.org/10.1016/j.polymdegradstab.2009.04.014 SN - 0141-3910 SN - 1873-2321 VL - 94 IS - 8 SP - 1245 EP - 1253 PB - Applied Science Publ. CY - London AN - OPUS4-19516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sypaseuth, Fanni D. A1 - Gallo, Emanuela A1 - Çiftci, Serhat A1 - Schartel, Bernhard T1 - Polylactic acid biocomposites: approaches to a completely green flame retarded polymer N2 - Basic paths towards fully green flame retarded kenaf fiber reinforced polylactic acid (K-PLA) biocomposites are compared. Multicomponent flame retardant Systems are investigated using an amount of 20 wt% such as Mg(OH)2 (MH), ammonium polyphosphate (APP) and expandable graphite (EG), and combinations with Silicon dioxide or layered silicate (LS) nanofillers. Adding Kenaf fibers and flame retardants increases the E modulus up to a factor 2, although no compatibilizer was used at all. Thus, in particular adding EG and MH decreases the strength at maximum elongation, and kenaf fibers, MH, and EG are crucial for reducing the elongation to break. The Oxygen index is improved by up to 33 vol% compared to 17 vol% for K-PLA. The HB classification of K-PLA in the UL 94 test is outperformed. All flame retarded biocomposites show somewhat lower thermal stability and increased amounts of residue. MH decreases the fire load significantly, and the greatest reduction in peak heat release rate is obtained for K-PLA/15MH/5LS. Synergistic effects are observed between EG and APP (ratio 2:1) in flammability and fire properties. Synergistic multicomponent systems containing EG and APP, or MH with adjuvants offer a promising route to green flame retarded natural fiber reinforced PLA biocomposites. KW - Biopolymers KW - Composites KW - Flame retardance KW - Natural fibres KW - Thermal decomposition PY - 2017 U6 - https://doi.org/10.1515/epoly-2017-0024 SN - 2197-4586 SN - 1618-7229 VL - 17 IS - 6 SP - 449 EP - 462 PB - De Gruyter AN - OPUS4-42872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gallo, Emanuela A1 - Stöcklein, Waldemar A1 - Klack, Patrick A1 - Schartel, Bernhard T1 - Assessing the reaction to fire of cables by a new bench-scale method N2 - The recently approved EU Construction Products Regulation (CPR) applies to cables as construction products. The difficulty of predicting the fire performance of cables with respect to propagation of flame and contribution to fire hazards is well known. The new standard EN 50399 describes a full-scale test method for the classification of vertically mounted bunched cables according to CPR. Consideration of the material, time, and thus cost requires an alternative bench-scale fire test, which finds strong demand for Screening and development purposes. The development of such a bench-scale fire test to assess the fire Performance of multiple vertically mounted cables is described. A practical module for the cone calorimeter is proposed, simulating the fire scenario of the EN 50399 on the bench scale. The efficacy of this module in predicting full-scale CPR test results is shown for a set of 20 different optical cables. Key properties such as peak heat release rate (PHRR), fire growth rate (FIGRA), and flame spread are linked to each other by factors of around 5. In a case study, the bench-scale test designed was used to investigate the influence of the main components on the fire behaviour of a complex optical cable. KW - Optical cables KW - Construction products regulation KW - Bench-scale fire testing KW - Reaction to fire KW - Cone calorimeter PY - 2017 U6 - https://doi.org/10.1002/fam.2417 SN - 0308-0501 SN - 1099-1018 VL - 41 IS - 6 SP - 768 EP - 778 PB - Wiley AN - OPUS4-42092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -