TY - JOUR A1 - Despinasse, Marie-Claire A1 - Schartel, Bernhard T1 - Influence of the structure of aryl phosphates on the flame retardancy of polycarbonate/acrylonitrile-butadiene-styrene N2 - The impact of the chemical structure of four different aryl bisphosphates on the flame retardancy of bisphenol A polycarbonate/acrylonitrile–butadiene–styrene blends (PC/ABS) was investigated. The impact of the bridging unit was studied, by comparing bisphenol A bis(diphenyl phosphate) BDP with biphenyl bis(diphenyl phosphate) BBDP and hydroquinone bis(diphenyl phosphate) HDP; as well as the influence of an aromatic substitution by comparing BBDP with biphenyl bis (di-2,6-xylyl phosphate) BBXP. The blends were investigated in terms of pyrolysis (thermogravimetry TG, TG coupled with Fourier transformed infrared spectroscopy (FTIR) and mass spectrometry (MS)) and fire performance (cone calorimeter, LOI, UL 94). The decomposition temperature of the flame retardant is a main parameter enabling a condensed phase interaction with PC decomposition products. The phosphate esters reacting with phenolic groups during pyrolysis were shown to increase cross-linking and reduce the hydrolysis/alcoholysis of the carbonate group. Variation of the aromatic substitution with the use of biphenyl bis (di-2,6-xylyl phosphate) led to reduced performance, highlighting the importance of the reactivity of the flame retardant with the decomposing PC. KW - Bisphenol A polycarbonate/acrylonitrile–butadiene–styrene (PC/ABS) KW - Flame retardancy KW - Flammability KW - Phosphate esters KW - Pyrolysis PY - 2012 DO - https://doi.org/10.1016/j.polymdegradstab.2012.07.005 SN - 0141-3910 SN - 1873-2321 VL - 97 IS - 12 SP - 2571 EP - 2580 PB - Applied Science Publ. CY - London AN - OPUS4-26969 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Despinasse, Marie-Claire A1 - Schartel, Bernhard T1 - Aryl phosphate-aryl phosphate synergy in flame-retarded bisphenol A polycarbonate/acrylonitrile-butadiene-styrene N2 - The pyrolysis and fire performance of bisphenol A polycarbonate/acrylonitrile-butadiene-styrene (PC/ABS) flame-retarded by a mixture of two aryl bisphosphates were investigated by thermogravimetry-coupled with FTIR, oxygen index (LOI), UL 94 and cone calorimeter. Both flame retardants, bisphenol A bis (diphenyl phosphate) BDP and hydroquinone bis (diphenyl phosphate) HDP, show gas-phase and condensed-phase actions. When mixed together at different ratios, a synergy is observed in terms of pyrolysis and fire residues as well as in effective heat of combustion (THE/ML). The synergisms were quantified and confirmed mathematically by the evaluation of the synergistic effect index (SE). All LOI values for the flame-retarded blends are between 29% and 32%, as opposed to 23% for PC/ABS, and UL94 testing results in V-0 at 1.6 mm instead of HB. Investigations on the binary system BDP + HDP reveal that BDP and HDP interact with each other, yielding stable intermediate products which are proposed to increase the thermal stability of the PC/ABS + BDP/HDP blends. Oligomeric phosphate esters are presumed to form via transesterification. KW - Flame retardancy KW - PC/ABS KW - Pyrolysis KW - Aryl phosphate KW - Synergy KW - Combustion PY - 2013 DO - https://doi.org/10.1016/j.tca.2013.04.006 SN - 0040-6031 SN - 1872-762X VL - 563 SP - 51 EP - 61 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-28515 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -