Energetic Binders and Plasticizers

Energetic binders and plasticizers for explosive compositions or formulations. 

One disadvantage of the polymer-bonded explosives of the first generation, is that the non-energetic binder (polymer) and plasticizer lessened the performance. To overcome this problem energetic binders and plasticizers have been developed. The most prominent examples for energetic binders are (Fig. 1.5, a) ... 

Some compounds of general structures (137) and (138) have hydroxy or carboxy termini, making them potential monomers for the synthesis of energetic polymers (binders) and plasticizers for both explosive and propellant formulations. ... 

While TKX-50 shows good compatibility with other energetic fillers, binders and plasticizers as well as with most metals and metal oxides (Tab. 9.15), its purity is crucial in order for it to exhibit good compatibility with all of the above for use in formulations. 

There are a number of inert binders such as polyester, epoxy, polysulfide, polyurethane which have been reported as binders for composite propellants and plastic bonded explosives (PBXs). At present, hydroxy-terminated polybutadiene (HTPB) is regarded as the state-of-the-art workhorse binder for such applications. However, the recent trend is to use energetic binders such as poly [3,3-bis(azidomethyl oxetane)] [poly(BAMO)], poly (3-azidomethyl-3-methyl oxetane) [poly(AMMO)], PNP, GAP diol and triol, nitrated HTPB(NHTPB), poly(NiMMO), poly(GlyN) and nitrated cyclodextrin polymers poly(CDN) for PBXs and composite propellants in order to get better performance. 

Fig. 1.5 Energetic binders (a) and energetic plasticizers (b). Synthesis of the NENA compound, ANTTO (c).

Compositions that hold together a charge of finely divided particles and increase the mechanical strength of the resulting propellant grain when it is consolidated under pressure. Binders are usually resins, plastics, or asphaltics, used dry or in solution (-> Energetic Binders). 

Epichlorohydrin or chloromethyloxirane is manufactured from allyl chloride, and, in 2006, had a merchant price of US 1.66 kg [4]. It is used as a building block in the manufacture of plastics, epoxy resins, phenoxy resins, and other polymers, and as a solvent for cellulose, resins, and paints, and has also found use as an insect fumigant. Epoxy resins (aryl glycidyl ethers) are manufactured successfully in large scale (1.2 x 10 metric tons in 2000) [26] and are widely used in a variety of industrial and commercial applications [27]. These are made by addition reactions of epichlorohydrins or by epoxidation of allyl ethers or esters (Table 1.1). Epichlorohydrin can be reacted with an alkali nitrate to produce glycidyl nitrate, an energetic binder used in explosive and propellant compositions. 

Propellants are explosive materials with low rates of combustion diat will ideally burn at uniform rates after ignition without requiring interaction with the atmosphere [1,2], They frequently involve several components, including an energetic oxidizer, a plasticizer to facilitate processing, and a polymeric binder. The specific impulse of such propellants is necessarily that of the composite mixture. Oui focus here is on chemical and structural factors affecting the specific impulse of the oxidizer, which will be designated as a monopropellant. 

Energetic plasticizers and binders for explosive and propellant compositions... 

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