Daniela Goedderz, Fraunhofer IBF
Action of the modes of action of PIN flame retardants, gas transport, flame topology and gaseous pyrolysis products, by a combination of optical diagnostics (planar laser-induced fluorescence spectroscopy of OH-radicals) and pyrolysis fragment analysis (TGA-FTIR). In collaboration with the RSM institute (TU Darmstadt), four different commercially available PIN FRs (APP, ATH, DEPZn and a spirocyclic organophosphonate) were tested in polypropylene. Different sample geometries (micro-sized particles and sticks) were compared and the OH-radical concentration was visualised during the combustion process. The use of optical diagnostics revealed peculiarities of the flame retardants used, such as small additional flames emerging from the surface of the sample. The aim is to improve understanding of how different PIN FRs act in the gas phase and to enable more efficient FR design and formulation.