Nitrate ester plasticizers

Nitrate Ester Plasticizers As discussed in Section 2.2.4 of Chapter 2, nitroglycerine (NG) is a high performance nitrate ester and is considered the first energetic plasticizer for commercial explosives. 

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Drees and co-workers synthesized a number of energetic azido plasticizers whose structures are based on those of known nitrate ester plasticizers. EGBAA (3), DEGBAA (4), TMNTA (5) and PETKAA (6) are synthesized from the corresponding chloroacetate esters with sodium azide in DMSO. 

S.L. (1992) Energetic composites of cyclodextrin nitrate esters and nitrate ester plasticizers, US Patent 5,114,506. 

Guan H, Liu Y et al (2007) Study on decreasing the burning rate of nitrate ester plasticized polyether propellant J Propul Technol 28(2) 216-219... 

R. Barefoot, "Compatibihty of Nitrate and Nitrate Esters," ia Conference on Compatibility of Propellants, Explosives, and Pyrotechnics with Plastics and Additives, Report NC-02P, AD PA, Washiagtoa, D.C., 1976, p. l-E-22. 

A huge number of ester and carbonate derivatives of polynitroaliphatic alcohol have been synthesized driven by the search for new explosives and energetic plasticizers and oxidizers for propellant and explosive formulations. Most of these are derived from 2-fluoro-2,2-dinitroethanol and 2,2,2-trinitroethanol ° and have excellent oxygen balances. Some examples are illustrated above (168-174) but more comprehensive lists can be found in numerous reviews. " " Direct esterification of polynitroaliphatic alcohols with nitric acid, mixed acid, or acetic anhydride-nitric acid has been used as a route to mixed polynitroaliphatic-nitrate ester explosives. ... 

Pentaerythritol tetranitrate (PETN) (3) is a powerful explosive which exhibits considerable brisance on detonation (VOD 8310 m/s at = 1.77 g/cm ). It is the most stable and least reactive of the common nitrate ester explosives. The relatively high sensitivity of PETN to friction and impact means that it is usually desensitized with phlegmatizers like wax and the product is used in detonation cord, boosters and as a base charge in detonators. Pentaerythritol tetranitrate can be mixed with synthetic polymers to form plastic bonded explosives (PBXs) like detasheet and Semtex-IA. A cast mixture of PETN and TNT in equal proportions is known as pentolite and has seen wide use as a military explosive and in booster charges. The physical, chemical and explosive properties of PETN commend its use as a high explosive. 

Though nitroglycerin (NG) is a liquid nitrate ester rather than a nitropolymer, it becomes a polymeric material when it is mixed with plasticizers. Like NC, NG is composed of a hydrocarbon structure with -O-NO2 bonds as oxidizer fragments. 

CA 41, 1842(1947) (Plastic explosives consisting of a liquid nitrate ester and a 1 3 mixture of sol insol Nitrocelluloses)... 

Propellant Composition. In principle, any solid ingredient which is chemically compatible with nitrate esters can be introduced into the propellant by way of the casting powder. Any liquid ingredient used in the formulation must also be a plasticizer or co-plasticizer for nitrocellulose. In practice, three major families of compositions have been developed, differing in the composition of the casting powder (see Table I for typical compositions) ... 

The cyclodextrins can be nitrated using conventional techniques that are used for the preparation of NC where the degree of nitration is controlled by varying the nitration conditions. The energetic organic nitrate esters used for plasticization of cyclodextrin nitrates include 1,1,1-trimethylole thane trinitrate (TMETN),... 

Nitroxyethyl Nitramine Plasticizers Nitroxy ethyl nitramine (NENA) plasticizers are a new family of energetic plasticizers which have emerged recently. These are effective plasticizers in energetic formulations, particularly in nitrocellulosic systems. NENAs contain both nitrate ester and nitramine functionalities and possess the general structure RN (N02).CH2.CH2.0N02 where R is methyl, ethyl, propyl, isopropyl, butyl and pentyl. 

Although Lhe first cellulose plastic (cellulose nitrate plastic-based on an inorganic ester of cellulose) was developed in 1865. the first organic cellulose ester plastic was not offered commercially until 1927. In that year, cellulose acetate plastic became available as sheets, rods, and tubes. Two years later, in 1929. it was offered in the form of granules for molding. It was the first thermoplastic sufficiently stable to be melted without excessive decomposition, and it was the first thermoplastic to be injection molded. Cellulose acetate butyrate plastic became a commercial product in 1938 and cellulose propionate plastic followed in 1945. The latter material was withdrawn after a short time because of manufacturing difficulties, but it reappeared and became firmly established in 1955. 

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