A non-fire-retardant and a fire retardant polyurethane foam are tested under a nitrogen environment using thermogravimetry at different heating rates of 1, 5, 20 and 60°C min 21 to obtain the foams' decomposition behaviours. During decomposition, both foams experience two major mass loss reactions with the second reaction consuming most of the fuel. Three graphical techniques applied to calculate the kinetic properties governing each reaction are kinetic analysis, the Arrhenius plot method and the inflection point methods. In general, these methods are compatible with the pyrolysis model within Fire Dynamics Simulator Version 5 and Gpyro. A normalised version of the inflection point methods is also developed to improve the suitability of the kinetic properties with the simplest decomposition scheme of the pyrolysis model. A consistent trend is noted in the calculated kinetic properties of both foams regardless of the calculation techniques applied.
For modeling the burning behavior of medium density fiberboard (MDF), pyrolysis kinetics was experimentally investigated through simultaneous differential scanning calorimetry and thermogravimetric analysis (SDT) experiments. Three decomposition models with up to four pyrolyzing components (phenol−formaldehyde (PF) resin, hemicellulose, cellulose, and lignin) were used to model the pyrolysis process. Genetic algorithm (GA) was applied to produce the kinetic properties based on the experimental thermogravimetric (TG) curves. On the other hand, the heat of pyrolysis was determined from the differential scanning calorimetry (DSC) measurements. The kinetic properties determined by the genetic algorithm are found to be consistent with those from other sources within the literature. Unlike natural biomass materials with only one endothermic peak, MDF presents two noticeable endothermic peaks from the DSC results. This shows two apparent endothermic regions during the pyrolysis process. A combined analysis of the DSC curves and the decomposition model demonstrates that the first endothermic region is mainly caused by the pyrolysis of PF resin which is also influenced by the exothermic reaction of hemicellulose pyrolysis. As a result, the first endothermic region has a higher heat of pyrolysis, 530 kJ/kg, compared to the second endothermic region, 150 kJ/kg. The second endothermic region is mainly caused by the cellulose pyrolysis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.