High-density polyethylene thermal degradation and gaseous compound evolution in a cone calorimeter

In this paper, the thermal degradation of pure high-density polyethylene (HDPE) has been studied in a cone calorimeter (CC) under well-ventilated conditions with a piloted ignition. Ten CC irradiance levels (from 15 to 80 kW m−2) have been applied to HDPE sample to characterize their influence on the thermal degradation parameters (ignition time (tig), critical heat flux (CHF), mass loss rate (MLR) and specific mass loss rate (SMLR)) as well as on the concentrations of exhaust gases emitted during the combustion process. During our experiments, gaseous compound mole fractions have been quantified simultaneously by a Fourier transformed infrared (FTIR) spectrometer and another gas analyzer. Thus, several main species (CO, CO2, H2O, NOx, lightweight hydrocarbons and O2) with concentrations and emission yields of high or non-negligible consistency have been encountered, regardless of the external heat flux considered. Furthermore, using the 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-HDPE thermal degradation results in cone calorimeter in air are presented.
► Exhaust gas concentrations are measured by FTIR spectrometer and gas analyzer.
► Thermal and physical properties (tig, CHF, MLR) are calculated for ten heat fluxes.
► Species concentrations, emission yields and C–H atomic balances are presented.
► EHC, HRR, THR and Yi data are in good accordance with previous literature results.