Final decomposition temperature

The thermo gravimetric analysis (TGA) was performed. The comparison of initial decomposition temperature (IDT) and final decomposition temperature (FDT) of... 

The recording of more prono qced horizontal mass plateaus in the TG curve is possible by use of a quasistatic heating rate mode, as previously mentioned. This method was first used by Honda (9) and also by Lufcaszewski and Redfern (6) and Paulik and Paulik (21). With th s technique, provision is made for the interruption of the linear temperature rise cycle and continuation of the heating at a constant fi ed temperature. This method gives mass-loss curves that are, in general, steeper than those obtained under dynamic conditions and provides more accurate data on the final decomposition temperatures. Io... 

IDPT Integral procedure decomposition temperature FDT Final decomposition temperature... 

The mass-loss fraction of wood treated with flame retardant is greater than that of untreated wood in the initial stage, but it subsequently becomes smaller. The wood with less mass loss in the second stage allows better flame retar-dancy. Furthermore, wood that has a small exothermic enthalpy and a higher final decomposition temperature on the DSC curve has better flame retardancy. The exothermic enthapy (AH) and final decomposition temperature (T() of fibreboard without flame retardant were 7.66 kjg" and 556.0 °C, respectively, whereas those of fibreboard treated with flame retardant were 5.49 kj g and 587.5 °C, respectively. 

DTG data Tan initial decomposition temperature maximum decomposition temperature end final decomposition temperature decomposition temperature interval Wt weight loss in... 

Instrumental factors. Heating rate. When a substance is heated at a fast rate, the temperature of decomposition will be higher than that obtained at a slower rate of heating. The effect is shown for a single-step reaction in Fig. 11.4. The curve AB represents the decomposition curve at a slow heating rate, whereas the curve CD is that due to the faster heating rate. If TA and Tc are the decomposition temperatures at the start of the reaction and the final temperatures on completion of the decomposition are TB and TD, the following features can be noted ... 

Orientation, wet stretching For plastics whose glass transition temperature (Tg) is above their decomposition temperature, orientation can be accomplished by swelling them temporarily with plasticizing liquids to lower their Tg of the total mass, particularly in solution processing. As an example, cellulose viscous films can be drawn during coagulation. Final removal of the solvent makes the orientation permanent. 

This is the dominant overall reaction for the decomposition on platinum or tungsten at 200 and 380 °C, respectively40. Most workers on hydrazine decomposition flames41-44, in which the reactions are homogeneous, report a stoichiometric equation similar to (b) for final flame temperatures up to 1900 °K. Measurements of MacLean and Wagner45 on decomposition flames and of Husain and Norrish37 on the flash photolysis of hydrazine indicate the contribution of the overall reaction... 

The heat transfer process in the combustion wave of TAGN consists of three zones, similar to what was illustrated for HMX in Fig. 5.5. Zone I is the solid phase, the temperature of which increases exponentially from the initial temperature, Tg, to the decomposition temperature, without chemical reaction. Zone II is the condensed phase, the temperature of which increases from T to the burning surface temperature, T, in an exothermic reaction. Zone III is the gas phase, the temperature of which increases rapidly from to the final combustion temperature, Tg, in an exothermic reaction. 

DSC and DTA measurements show melting of ADN, NH4N(N02)2, at 328 K, the onset of decomposition at 421 K, and an exothermic peak at 457 K.l l Gasification of 30% of the mass of ADN occurs helow the exothermic peak temperature, and the remaining 70% decomposes after the peak temperature. The decomposition is initiated by dissociation into ammonia and hydrogen dinitramide. The hydrogen dinitramide further decomposes to ammonium nitrate and NjO. The final decomposition products in the temperature range 400-500 K are NH3, HjO, NO,... 

The OOQOOH radical may isomerize further, similar to the reactions of RO2. The isomer-ized product decomposes into a ketohydroperoxide5 species and one OH radical. The keto-hydroperoxide is fairly stable below about 800 K, but at higher temperatures it decomposes to yield two additional radicals [426]. Thus it is not until this final decomposition step of the ketohydroperoxide that chain branching is finally achieved in the low-temperature mechanism, yielding three radicals from the initial peroxide radical. 

A series of 11 nitrobenzaldehydes was examined by TGA, DSC and ARC techniques. Only 5-hydroxy-2-nitrobenzaldehyde decomposed exothermally in an unsealed container, but all did so in sealed capsules, under dynamic, isothermal or adiabatic conditions, with evolution of much gas. Initial decomposition temperatures in °C (compound, ARC value, and DSC value at 10°/min, respectively, followed by ARC energy of decomposition in kJ/g) were - 2-nitro-, 176, 220, 1.44 3-nitro-, 166, 218, 1.94 4-nitro-, 226, 260, 1.27 2-chloro-5-nitro-, 156, 226,. 697 2-chloro-6-nitro-, 146, 220,. 832 4-chloro-3-nitro-, 116, 165, 1.42 5-chloro-2-nitro-, -, 240, - 3-hydroxy-4-nitro-, -, 200, - 4-hydroxy-3-nitro-, -, 200, - 5-hydroxy-2-nitro-, -, 175, - 3-methoxy-4-nitrobenzaldehyde, -, 245°C, -. 4-Nitrobenzaldehyde showed by far the highest self-heating rate in ARC tests (approaching 100°/min at 240°C) anf the final pressure exceeded 170 bar when the pressure relief operated. The results are compared with those from various nitrobenzyl derivatives. 

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