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 T2 - Polymer Chemistry 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. PB - RSC KW - Flame retardant KW - Hyperbranched PY - 2019 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/48658 AN - OPUS4-48658 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-486589 SN - 1759-9962 SN - 1759-9954 VL - 10 IS - 31 SP - 4346 EP - 4358 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany