Chemical structures thermal stability tests

The LMU Munich research group has also been looking at tetrazole-free nitrogen-rich compounds that contain oxidizing groups such as nitramine functionalities. In this context, the preparation and structural characterization of dinitrobiuret (DNB) (Fig. 31) was carried out [109,110]. The high chemical and thermal stability of DNB and the determined critical diameter of 6 mm for DNB (Figs. 32, 33) in the Koenen test (steel shell test) is comparable to the values reported for HMX (8 mm), RDX (8 mm), or PETN (6 mm) and prompted us to obtain the thermodynamic data and detonation pressures and velocities for DNB in a combined experimental and theoretical study. 

Sample Test Data. Thirty different NLO chromophores were tested to provide a thermal stability index. Of these, seven were studied using both melting endotherm and decomposition exotherm disappearance whereas the other twenty-three compounds were studi using only the decomposition exotherm decreases. makes a total of thirty-seven samples whose data are given in Table m. The chemical structures corresponding to the sample names are shown in Figures 5,6 and 7. 

PPS is insoluble in all known solvents below 200°C but above this temperature it is partially soluble in some aromatic and heterocyclic solvents. Its chemical structure imparts excellent thermal stability and maintenance of mechanical properties at elevated temperatures. PPS is rated as non-burning by industry flammability tests. 

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