Analysis of principal gas products during combustion of polyether polyurethane foam at different irradiance levels

This paper studies the release of the principal gas species produced during the combustion of a non-flame-retarded Polyether Polyurethane Foam (PPUF) of density of 20.9 kg m−3 in the cone calorimeter. Five irradiance levels are studied: 10, 20, 30, 40 and 50 kW m−2. Heat release rate, mass-loss rate and bulk gas mass flow are measured. The mass flow and yields of gas species are measured as well. The analysis of release of gas species relative to time allowed the study of the different stages of PPUF kinetics and to quantify the gas composition. Of the twenty-two different gas species that were monitored simultaneously, the principal species found were CO2, CO, H2O, NO and total hydrocarbons. According to species release, two decomposition stages for PPUF are identified. In the first stage, the solid structure breaks down carrying the decomposition of isocyanate, and in the second stage the polyol decomposes. These two stages are in agreement with the decomposition mechanism proposed in the literature. However, the data presented here is the first experimental study of burning behavior of PPUF taking into account the release of gas species too. An elemental analysis was performed and the chemical formula of the virgin material was determined. This allows the mass balance of the elements in the virgin foam content with the gaseous product content. The effective heat of combustion and the ratio between heat release rate and CO2 mass flow are calculated at each of the irradiance levels.