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 DO - 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 - 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 - 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 DO - 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 - 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 DO - 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 - 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 DO - 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 - Pappalardo, Salvatore A1 - Russo, Pietro A1 - Acierno, Domenico A1 - Rabe, Sebastian A1 - Schartel, Bernhard T1 - The synergistic effect of organically modified sepiolite in intumescent flame retardant polypropylene N2 - The pyrolysis, flammability and fire behavior of polypropylene (PP) containing an intumescent flame retardant and sepiolite nanoparticles were investigated by performing thermogravimetry, oxygen index (LOI), UL-94, and cone calorimeter tests. The combination of 0.5 wt% of premodified sepiolite (OSEP) with 12 wt% of a commercial intumescent flame retardant showed a clear synergy in LOI, UL-94 ranking and peak heat release rate. The ternary formulation achieved a V-0 classification and, consequently, allowed a reduction in the amount of flame retardant necessary to achieve this result. Whereas OSEP and pristine sepiolite nanoparticles (SEP) affect the performance in PP nanocomposites quite similarly, OSEP outperformed SEP in the combination with intumescent flame retardant. The cone calorimeter results and dynamic rheological measurements confirmed the synergistic effect between the nanofiller and the flame retardant resulting from the improved properties of the residual protective layer. KW - Polypropylene KW - Intumescent flame retardant KW - Sepiolite KW - Cone calorimetry KW - Low oxygen index PY - 2016 DO - https://doi.org/10.1016/j.eurpolymj.2016.01.041 SN - 0014-3057 VL - 76 SP - 196 EP - 207 PB - Elsevier AN - OPUS4-35854 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -