TY - JOUR A1 - Schartel, Bernhard A1 - Weiß, André T1 - Temperature inside burning polymer specimens: Pyrolysis zone and shielding N2 - On the basis of two examples, temperature measurements are proposed within burning polymer specimen during the cone calorimeter test; especially to gain deeper insight into the actual pyrolysis conditions and flame retardancy mechanism. The heating and pyrolysis within a poly(methyl methacrylate) specimen were characterized, discussing the characteristic maximum heating rates (165-90°Cmin-1 decreasing with depth within the specimen and >275°Cmin-1 at the initial surface), pyrolysis temperature (454-432°C decreasing in accordance with decreasing heating rates), thickness of the pyrolysis zone (0.5-1.3 mm) and its velocity (1.2-2.1 mm min-1) as a function of sample depth and burning time. Thermally thick behaviour corresponds to a pyrolysis zone thickness of 0.74 mm and a velocity of 1.51 mm min-1 and occurs until the remaining specimen thickness is less than 8 mm. The shielding effect against radiation occurring in a layered silicate epoxy resin nanocomposite was investigated. It is the main flame retardancy effect of the silicate-carbon surface layer formed under fire. The reradiation from the hot surface is increased by a factor of around 4-5 when an irradiance of 70kWm-2 is applied. The energy impact into the pyrolysis zone is crucially reduced, resulting in a reduction of fuel production and thus heat release rate. KW - Cone calorimeter KW - Pyrolysis KW - Nanocomposite KW - Poly(methyl methacrylate) KW - Pyrolysis zone KW - Pyrolysis front KW - Shielding effect PY - 2010 DO - https://doi.org/10.1002/fam.1007 SN - 0308-0501 SN - 1099-1018 VL - 34 IS - 5 SP - 217 EP - 235 PB - Heyden CY - London AN - OPUS4-21724 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -