High energy density materials

S. Iyer and co-workers, "New High Energy Density Materials for Propellant AppHcations," in 5th International Gun Propellant and Propulsion Symposium, ARDEC, Picatinny Arsenal, N.J., Nov. 1991, pp. 18—21. 

High Energy Density Materials Volume Editor Klapotke, T. H. 

Keywords Tetrazoles Tetrazines High energy density materials Nitrogen-rich compounds Energetic materials... 

Collaborations that were initiated during previous contract years have been continued throughout 1996-1997 in an effort to further evaluate the fuel properties of the new high-energy-density materials. A brief description of each of these collaborative efforts follows. 

Fig. 4.3 Molecular structures of high energy density materials.

TMETN is a liquid at room temperature and the production process of NG-TMETN propellants is the same as that described for NG-NG propellants. The shock sensitivity of TM ETN is sufficiently lower than that of NG that no desensitizers are needed for NC-TMETN propellants. Instead of the DEP or TA used as low energy density plasticizers and stabilizers of NC-NG propellants, TMETN is mixed with TEGDN, which is a dinitrate ester and hence a relatively high energy density material. Thus, the overall energy density of double-base propellants composed of NC-TMETN is equivalent to or even higher than that of NC-NG double-base propellants. 

Klapotke, T. M., and Ang, H.-G., Estimation of the Crystalline Density of Ni-tramine (N-N02-based) High Energy Density Materials (HEDM), Propellants, Explosives, Pyrotechnics, Vol. 26, 2001, pp. 221-224. 

Matsunaga, T., and Pujiwara, S., Material Design of High Energy Density Materials, Explosion, Japan Explosives Society, Vol. 9, No. 2, 1999, pp. 100-110. 

Polynitrogens as promising high-energy density materials computational design... 

The high heat of formation of the N3 cation ( 350 kcal/mol) makes it very attractive as a component of high energy density materials (HEDMs). However, its large vertical electron affinity (vEA) of 6.1 eV poses a problem So far, the preparation of only NsAsFg, N ShF, and NjSb2Fu has been reported. The oxidation of Br2 (IP 10.5 eV) by N SbFj shows that N3 is also susceptible to nucleophilic attack by Lewis bases. Calculations on NjNj show that such a crystal may exist, but nucleophilic attach of the anion is a likely side-reaction. We think that less electronegative derivatives of N3 may be less sensitive to both reduction and nucleophilic attack. 

All NCI, NBr, and NI compounds are thermodynamically nnstable (AHf > 0). Some, bnt not all binary NF componnds are exothermic species, with NF3 as the most stable species. During the 1960s, NF componnds were investigated as rocket propellants. Today, NF compounds are used in chemical lasers and as high-energy density materials, but no componnd... 

Another application of rhodium carbenoid chemistry relates to the synthesis of strained-ring nitro compounds as high energy-density materials. Nitrocyclo-propanes are the simplest members of this class of compounds and catalyzed additions of a nitrocarbene to an olefin have only been described recently [40], Detailed studies have shown that the success of the reaction is, as expected, dependent on both the alkene and the nitrodiazo precursor. Consistently with the electrophilic character of rhodium carbenoids, only electron-rich alkenes are cyclopropanated. The reaction has been extended to the synthesis of nitrocyclo-propenes but the yields are good for terminal acetylenes only [41]. 

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