Search

The quantitative structure‐property relationship (QSPR) approach has widely been used to predict several physicochemical properties of materials employing the information obtained from their chemical structures (numerical descriptors). In the present work, we have generated three individual QSPR models for three different endpoints for a large number of polymers in order to determine their fire retardant property such as heat release capacity, total heat release, and %Char, using the only two‐dimensional descriptors with definite physicochemical meaning. Relevant subsets of descriptors were selected employing a genetic algorithm approach; subsequently, the selected descriptors were utilised for the identification of the best combination of the variables for the model generation, while the final models were developed employing the partial least squares (PLS) regression algorithm. The generated models were rigorously validated using various internationally accepted internal and external validation metrics. All the models showed promising statistical quality in terms of determination coefficient R2 (0.802, 0.842 and 0.826), cross‐validated leave‐one‐out Q2 (0.759, 0.810 and 0.752) and predictive R2pred or Q2ext (0.810, 0.900 and 0.847) for HRC (nTraining=62, nTest=28), THR (nTraining=64, nTest=21) and %char (nTraining=49, nTest=21) datasets, respectively. All the certified models were used for prediction of flammability characteristics of 37 external set compounds, and further, the quality of prediction was determined by using the PRI software tool. The final models of HRC, THR and %Char formation of polymers may be useful to predict the flammability characteristics of polymers quickly before their synthesis and used as a better alternative approach to the experimental testing of flammability of polymers. [ABSTRACT FROM AUTHOR]

Total heat release of a polymer is the heat of complete combustion of the pyrolysis gases per unit its initial mass. Microscale combustion calorimetry, an oxygen consumption technique, identifies the total heat release of polymers that is a key parameter for predicting polymer flammability where their measured data can be confirmed by thermogravimetric analysis (TGA) and derivative TGA (DTG) data. The simplest model is introduced to predict the total heat release of different polymers on the basis of their repeat units that may contain chemical groups/moieties. In contrast to the available quantitative structure–property relationships methodology, the new method simply requires only elemental composition of repeat unit of a desired polymer without using complex molecular descriptors and computer codes where they need expert users. For the measured total heat release of 122 polymers, the predicted results are compared with the calculated data of the latest group additivity methods. The root mean square deviation, mean absolute deviation and maximum of errors of the new model are 4.5, 3.4 and 15.3 kJ g−1, which are lower than those predicted by group additivity method, i.e., 9.0, 5.8 and 35.7 kJ g−1, respectively. [ABSTRACT FROM AUTHOR]

The combustion and thermal characteristics of fire retardant-treated pine (Pinus densiflora) were evaluated according to the KS F ISO 5660-1 (2003) standard, using a cone calorimeter. The specimens were treated with fire-retardant chemical compounds using pressure-impregnation equipment to reliably impregnate the compounds inside the wood. The heat release rate value of the fire retardant-treated wood specimens showed that the heat release time was delayed. A reduction of the total heat release value can indicate that fire was prevented from igniting in the materials during combustion. The microstructures of natural specimen and treated fire-retardant chemical compounds specimen were determined by scanning electron microscopy. It also confirmed that the pressureimpregnation processing method was effective in comparison to the other treatment methods. [ABSTRACT FROM AUTHOR]

PET laminated photovoltaic modules present a high level of fire hazard, with varying levels of risk in complex external environments. This paper presents the experimental results of the ignition and combustion behavior of a PET laminated photovoltaic panel using the Fire Propagation Apparatus. The ignition time, heat release rate, combustion equivalent ratio, and total heat release were measured at different external heat flows and ventilation levels. The ignition time was determined as a function of the external radiant heat flow and the ventilation volume, respectively. The experimental results showed that the ignition time was sensitive to the change of external heat flow under different experimental conditions, but at lower external heat flow, the increase of ventilation had a great contribution to the shortening of the ignition time. The oxygen consumption method was used to determine the heat release rate under multiple boundary conditions, the value of which depends on the close coupling effect of external radiant heat flow and ventilation and is positively correlated with both. The immediate effect of boundary conditions on combustion efficiency was analyzed by equivalence ratios. For the total heat release, the external radiant heat flow directly plays a decisive role, but the ventilation volume can play a great role in promoting, especially under the low external heat flow. • Combustion tests of PET laminated photovoltaic panels using FPA. • Data analysis of fire hazard assessment under multi boundary conditions. • The influence of ventilation rate on ignition time and heat release rate is concerned. • Analysis of the coupling effect of boundary conditions on combustion efficiency. [ABSTRACT FROM AUTHOR]

Composite materials like FRPs offer the advantages of the high strength and stiffness with their low density and highly flexible shaping, thus, their potential in replacing conventional materials such as aluminium and steel for prefabrication of modular residential and office applications. The main limitation of fibre reinforced polymer composites (FRPCs) is their relatively poor fire performance. In this study, two CFD models using the modified Mc Grattan and the modified Coats Redfern – Kissinger method were developed to mimic the testing conditions of thermo-gravimetric analysis and cone calorimeter. Validation with experiments proves that the models can realistically predict the fire growth index (FIGRA) and total heat release (THR) of the organoclay/glass fibre reinforced polymer (GFRP) laminates. Two other CFD models were also developed to predict the behaviour of GFRP façade panel, where GFRP laminates are sandwiched with the foam core and undergo ISO 9750-1:2013 conditions in a typical office defined by the National Construction Code, Australia and a city office building in Netherlands. In the first case, 5% organoclay in GFRP prevents flash-over from happening and also the flame from spreading in the horizontal direction. In the second case, organoclay/GFRP panel is tested with different configurations. FIGRAs and THRs in all the selected configurations were found to be well below the thresholds required for building environment. [ABSTRACT FROM AUTHOR]