A thermal stability

With this assumption, the basic cross-section of the conductor and the enclosure can be chosen. It is then counterchecked whether the size so chosen is adequate to reach a thermal stability. When desired, the t can be suitably modified to reach thermal equilibrium. The sizes can be optimized by plotting a few theoretical graphs ... 

This polymer is typical of the aliphatic polyolefins in its good electrical insulation and chemical resistance. It has a melting point and stiffness intermediate between high-density and low-density polyethylene and a thermal stability intermediate between polyethylene and polypropylene. 

It is reported that the BBL polymers have a thermal stability as assessed by TGA tests in excess of 600°C whilst they also show negligible heat loss after several hundred hours in air at 370°C. 

The poiymer has a Qc of 3096cai/g (Ref liq H20 at 25°), an impact sensy of 85cm at the 50% point using a BM machine with a 2kg wt (RDX, 28cm), power by Bal Mortar of 96 (TNT=100), a thermal stability at 65.5° of 10 mins using a 1.3g sample with Kl-Starch paper as the indicator (Ref NC, 10 mins, no color), a thermal stability at 134.5° of 78 mins using Methyl violet indicator paper (Ref NC, 30 mins, no color), and a rel vise of 1.7 centipoises using a 1% acet soln at 25°... 

However, pMBCl 42 has a thermal stability issue and is expensive (Aldrich price 25 g for 69.90 the largest bottle). On the other hand, pMBOH 43 is stable and economically viable (Aldrich price 500 g for 84.90 the largest bottle). It was found that mono-N-alkylation of 36 proceeded well by slow addition (over 3 h) of 43 to a solution of 36 in acetonitrile in the presence of a catalytic amount of acid (p-TsOH) at 70 °C, as shown in Scheme 1.16. Slow addition of alcohol 43 minimized the self-condensation of 43 to form symmetrical ether 44, which was an equally effective alkylating agent. The product 41 was then directly crystallized from the reaction mixture by addition of water and was isolated in 90% yield and in >99% purity. A toluene solution of 41 can be used for the next reaction without isolation but the yield and optical purity of the asymmetric addition product were more robust if isolated 41 was used. In general, the more complex the reaction, the purer the starting materials the better. 

Most exact methods Correlations between the Shifts of v(m for a Thermal stability... 

The first aim of a thermal stability screening test (e.g., DSC/DTA) is to obtain data on the potential for exothermic decomposition and on the enthalpy of decomposition (AHd). These data, together with the initial theoretical hazard evaluation, are used in reviewing the energetic properties of the substance (Box 4) and the detonation and deflagration hazards of the substance (Boxes 7 and 8). The screening tests also provide data on the thermal stability of the substance or mixture, on the runaway potential, on the oxidation properties, and to a lesser extent, on the kinetics of the reaction (Box 10). 

A thermal stability study was first carried out to determine the following information (1) the solidification temperature as a function of the concentration of the sulfonate (2) the enthalpy of decomposition by DTA (3) the autocatalytic nature of the decomposition by Dewar flask (4) kinetic data for decomposition by Dewar flask (5) the time to maximum rate by ARC, and (6) the heat generation as a function of temperature, also by ARC. In addition, the enthalpy of dilution was determined for various potential water leak rates. These data were useful in defining emergency response times. 

The evaluation process is completed with a thermal stability assessment of the products within the process temperature and time ranges. This assessment includes possible interactions of the products with the materials of construction of the equipment used. The methodology is the same as the one previously described for the reactants. It needs to be emphasized that depending on the circumstances the investigation cannot be limited to the pure products. Sometimes representative samples of reaction mixtures at different conversion stages need to be assessed as well. 

Zeolite Maximum pore size (A) Thermal stability (°C) Typical conditions for in situ synthesis methods ... 

Complexes 75 are remarkably stable at room temperature in the solid state and, when heated, they start to decompose only at about 130 °C (Cr) or 145 °C (W). Such a thermal stability is undoubtedly associated with their strongly dipolar nature, in which six possible ylide-type resonance forms contribute to the bonding (Fig. 12). As expected, analysis of the electronic structure of complex [W (=C=C=C=C=C=C=C(NMe2)2 (CO)5] by DPT methods showed that the LUMO is mostly localized on the odd carbon atoms of the chain, whereas the HOMO is on the even carbons. In accord with these electronic features, it was found that [W =C=C=C=C=C=C=C(NMe2)21(00)5] readily adds dimethylamine across the 05=05 bond, to give the isolable alkenyl-pentatetraenylidene derivative [W =C=C=C=C=C(NMe2)CH=C(NMe2)21(00)5] [69, 70]. 

In one test, 0.5 g was sealed in a thermal stability bomb and the temp was raised 5°C/min. At ca 120°, a violent exothermic reaction occurred, rupturing the burst diaphragm of the app at 1800 psi. Another test conducted on a 0.5 g sample at 60°C resulted in sudden de-compn after 3 hrs at that temp. The sample temp rose sharply and exceeded the scale limit of 250°C. The same tests on the 2.6 Dichloro deriv (qv) showed similar, but less severe, instability. 

It is reported by B.T. Taranto of Schering Corp, Bloomfield, NJ (Ref 2) that this reagent, used for spot visualization in chromatographic systems, presents a potential expln hazard. Tests of this compd and of the 2,6-Dihromo deriv (qv) in a thermal stability bomb showed both to be expl, but the dichloro deriv was not as unstable as the dibromo deriv Refs 1) Beil 7, 634 2) Anon, C EN 45,... 

A polyester backbone with two HFIP groups (12F aromatic polyester of 12F-APE) was derived by the polycondensation of the diacid chloride of 6FDCA with bisphenol AF or bisphenol A under phase-transfer conditions (120). These polymers show complete solubility in THF, chloroform, benzene, DMAC, DMF, and NMP, and form dear, colorless, tough films the inherent viscosity in chloroform at 25°C is 0.8 dL/g. A thermal stability of 501°C (10% weight loss in N2) was observed. 

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