Thermal stability test methods

Example 1 Typical Outputs of Thermal Stability Test Methods As discussed in detail later in Section 2.3, various techniques with different working principles are available to identify the thermal reactivity hazards of individual substances and reaction mixtures. Some examples are presented here. 

Fenlon, W. J., "A Comparision of ARC and Other Thermal Stability Test Methods," Pkant/Operations Progress, 3, No. 4,197 (1984). 

Stavinoha, L. L. 1998. Summary Overview. In Report, Oxidative and Thermal Stability Testing Methods for Biodiesel (pp. 1 1). San Antonio TX Southwest Research Institute. 

Use of thermal stability tests (DTA s) to determine the heat sensitivity of a given process mixture is desirable. Recent advances in analytical methods permit good calorimetric determination of heat of reaction. Heat of reaction data are critical for exothermic reactor vent sizing. Heat impact from fire is usually small in comparison, but should not be neglected. 

In 55% of the cases, the accidents could have been foreseen by use of risk analysis, and in 35% of the cases by thermal stability testing. Different methods of stability testing were evaluated comparatively during the investigation of a runaway exothermic reaction which occurred during the preparation of a component mixture for a sealing composition in a 1200 1 reactor only DSC was effective in identifying the cause of the hazard. 

Temperature Developed on Detonatlon(or Explosion) can be detd experimentally with a fair degree of accuracy by optical methods and can also be estimated by calcn as discussed in the following Refs l)E.Sarrau, "Theorie des Explosifs, Gauthier-Villars, Paris(1895),16—17 2)Marahall 2, (1917),453 459—60 3)Barnett( 1919),200 4) Venn in, Bur lot Lecorche( 1932), 36—50 5)Stettbacher( 1933),85 6)H.Muraour, "Poudres et Explosifs, Paris( 1947), 71—3 7)Stettbacher(1948),14 8)Stettbacher( 1952), 17 Testing Galleries. See Galleries for Testing Permissible Explosives Thermal Stability Tests. See Heat Testa... 

Tafiani Test. A manometric thermal stability test for NC and proplnts, described earlier in Vol 1, XXIV to XXV, with its many modifications. In all modifications of the method the test tube containing the sample preheated to the desired temp (135° for NC, 110° for proplnts) is evacuated, and the increase in pressure produced by the gaseous decompn products is measured with a Hg manometer. The test is usually terminated when the pressure has attained 100mm Hg... 

The thermal stability test used at Chevron is an adaptation of Du Pont Test Method 21-61 (10) and is described in the previous chapter. 

Heat Tests (Thermal Stability Tests) include among others the followiitg l)Abels or KI Test (qv) 2) American Test at 65-5° or 80° (See Ref 2 p 80 and under Surveillance Tests in this section) 3)Angeli s Test (See Ref 2, p 90 and p A403 of this volume) 4)Bergmann-Junk Test (qv) 5)Brame s Test (Ref 2, p 88) 6)Brunswig 8 Test (Ref 2, p 86) 7)Chiataviglio Cotbino s (Ref 2, p 88) 8)Conductivity Method (Ref 2,... 

There are several points to be kept in mind when using physical testing as part of process hazard evaluation. First, the limitations of the test method should always be kept in mind. For example, it has been pointed out that different thermal stability tests give different exotherm detection temperatures. In most cases it is not possible to define an exact exotherm onset because the decomposition reaction s rate does not go to zero as the temperature is lowered. Overconfidence in test results can be just as much of a hazard as no knowledge at all if the limitations of the tests are forgotten. 

GB/T 13464-92 Thermal Analysis Test Method for Thermal Stability of Materials... 

Test Method for Rust-Preventing Characteristics of Inhibited Mineral Oil in the Presence of Water Chrysler Bench Oxidation Test (CBOT) Mercomatic Oxidation Test Ford Thermal Stability Test Turbo Hydra-Matic Oxidation Test (THOT)... 

Test method for transition temperatures of polymers by thermal analysis Reporting thermoanalytical data Definition of terms relating to thermal analysis Test method for assessing the thermal stability of chemicals by methods of thermal analysis... 

Other Thermal and Environmental Stability Test Methods. 303... 

Antioxidants have been shown to improve oxidative stabiHty substantially (36,37). The use of mbber-bound stabilizers to permit concentration of the additive in the mbber phase has been reported (38—40). The partitioning behavior of various conventional stabilizers between the mbber and thermoplastic phases in model ABS systems has been described and shown to correlate with solubiHty parameter values (41). Pigments can adversely affect oxidative stabiHty (32). Test methods for assessing thermal oxidative stabiHty include oxygen absorption (31,32,42), thermal analysis (43,44), oven aging (34,45,46), and chemiluminescence (47,48). 

Assessing the Thermal Stability of Chemicals by Methods of Differential Thermal Analysis, American Society for Testing and Materials, Philadelphia. 

The choice of reaction medium is important and the most important criteria that must be complied with are (i) unreactivity towards reactants and products, (ii) a large range between the melting and boiling points, (iii) good chemical and thermal stability, (iv) compatibility with the analytical methods used to test the reaction, and (v) good solubility of the reactants, and sometimes of products, even if excellent results can be obtained in the heterogeneous phase. 

Many methods have been proposed and are used to study the thermal stability of propellants and to ensure the absence of possible autocatalysed decompositions during storage. None are sufficiently reliable to merit individual description. In practice, stabilisers are added, the usual being diphenylamine for nitrocellulose powders and symmetrical diethyl diphenyl urea (carbamate or centralite) for double base propellants. Provided a reasonable proportion of stabiliser remains, the propellant can be assumed to be free from the possibility of autocatalytic decomposition. The best test of stability is therefore a chemical determination of the stabiliser present. 

We have synthesized two small scale batches (PA-DBX 1 and 2) of 2-3 g each and one intermediate scale batch (PA-DBX 3) of 8-10 g of DBX-1 from our NaNT. The procedure used to synthesize DBX-1 was based on literature methods.[5,6] For each batch, sensitivity tests, thermal stability by differential scanning calorimetry (DSC), and performance tests were performed and compared to the standard DBX-1 that was obtained from PSEMC (Pacific Scientific Energetic Materials Company, inventors of DBX-1). 

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