Characterization of thermal properties and analysis of combustion behavior of PMMA in a cone calorimeter

This paper deals with the thermal degradation of a black poly(methyl)methacrylate (PMMA) in a cone calorimeter (CC) in air with a piloted ignition. The influence of several heat fluxes (11 kW m−2 and 12 kW m−2, and ten values from 15 to 60 kW m−2 in steps of 5 kW m−2) on PMMA sample degradation and the decomposition chemistry has been studied. Thus, thermal properties have been deduced and calculated from ignition time and mass loss rate (MLR) curves. During our experiments, among compounds quantified simultaneously by a Fourier transformed infrared (FTIR) or gas analyzer, five main species (CO2, CO, H2O, NO and O2) have been encountered, regardless of the external heat flux considered. The main product concentrations allow calculation of the corresponding emission yields. Thus, mass balances of C and H atoms contained in these exhaust gases were able to be compared with those included in the initial PMMA sample. Using the standard oxygen consumption method, heat release rate (HRR), total heat release (THR) and effective heat of combustion (EHC) have been calculated for each irradiance level. Therefore, these different results (thermal properties, emission yields, HRR, THR and EHC) are in quite good accordance (same order of magnitude) with those found in previous studies.

► Black-PMMA thermal degradation results in cone calorimeter in air are presented.
► Exhaust gas concentrations are measured by FTIR spectrometer and gas analyzer.
► Thermal and physico-chemical properties are calculated for different heat flux.
► These MLR, HRR and Yi are in good accordance with previous literature results.
► A four-step kinetic model of degradation is proposed in the conclusion section.