Journal of Fire Sciences

This work deals in the first part, with the synthesis and characterization of a new-type carbonific. Two steps were used in the synthesis of the carbonific. Meanwhile, the structure was characterized by Fourier transform infrared spectroscopy (FTIR), magic-angle spinning nuclear magnetic resonance (MAS-NMR) ¹³C spectroscopy and elemental analysis. The addition of ammonium-polyphosphate (APP) and the carbonific into polyurethane (PU) varnish leads to a great improvement in its carbonization and flame-retardant (FR) performances. The second part deals with choosing the most effective combination of APP, carbonific and PU varnish. The last part deals with the evaluation of characteristic performances such as FR property, thermal stability of IFR/PU-based coatings, rheology of IFR/PU-based coating solutions and mechanical properties such as hardness, adhesion, flexibility of IFR/PU-based dry coating films.

A non-linear model of flashover, FLASHOVER A1, has been used to explore the dependence of the critical fire size necessary for the onset of flashover on the aspect ratio of the enclosure. It may be hypothesized that, overall, there is a dependence on aspect ratio. Further, it has been inferred that the critical upper layer temperature necessary for the onset of flashover is not fixed but depends upon the specific case assumed. It is not tenable to assume a single, fixed, temperature as a criterion for flashover, although this has often been done in the past.

Ammonium polyphosphate (APP) shows fire retardant activity in poly(butylene terephthalate (PBT), as the LOI values increase and the UL94 rating improves. TG, FT-IR and GC/MS data provide evidence that APP interacts with PBT. Addition of APP changes the composition of the solid, high and low boiling decomposition products as compared to those of neat PBT. The main reaction occurring on pyrolysis was shown to be ammonolysis of PBT resulting in the formation of various aromatic nitriles. The fire retardant effect was mainly attributed to the condensed-phase activity of APP.

Previously reported results for the Biot number in an oven heating test have been utilised in the calculation of convection coefficients, both to the sample itself and to a thermocouple measuring the oven temperature. A full heat balance on the thermocouple tip is performed in order to predict the accuracy with which the oven temperature - utilised in calculations following from oven heating experiments - can be measured.

The smoke concentration at a distant location down a hallway as a function of different openings of the room of fire origin is considered. A series of tests is reported and the smoke sustaining (residence) time, the concentration peak and the concentration buildup rate are investigated as functions of the size of the opening. The smoke sustaining (residence) time, the most important factor concerning smoke toxicity, is described by a novel concept, wavelength, in this study. Furthermore, it is worth emphasizing that the smoke concentration at the sampling point exhibits a phenomenon of vibration in the case of the smallest opening during the test.

Limiting oxygen index determination and TG methods results illustrate that the bromopolystyrene produced can flame-retard cured epoxy resin effectively by gas phase and condensed phase mechanisms. The results of thermal analysis (TG and DSC) and direct heating in air show that BPS loses bromine atoms mainly at 310-420°C at a high rate. The pyrolysis kinetics parameter n is zero, E is 209.8 kJ/mol and A is 2.6 × 10¹⁷, the rate constant and half-life also have been obtained. It is very stable below 200°C in air and is durable in use. The kinetics equation has larger practical value than the TG curves themselves.