Polymers energetic

Economic Aspects. Oxetanes are expensive monomers and are not readily available in commercial quantities. Commercial production of PBCMO has been discontinued its end uses were not able to support its comparatively high selling price. Energetic polymers prepared from appropriately substituted oxetanes have opened a new market for their use to prepare soHd rocket propeUants and explosives. Should this specialty market result in the large-scale production of these oxetanes even at current (1996) high prices and/or in a cheap synthetic route to oxetanes, this economic picture could change. 

As an energetic polymer, poly(glycidyl azide) (PGA) mance solid propellant binder [63,64]. For this purpose,... 

Aktive Binder energetic binders energetic polymers... 

The weak nucleophilic nature of polynitroaliphatic alcohols is also reflected in their slow reactions with isocyanates to yield carbamates. These reactions often need the presence of Lewis acids like ferric acetylacetonate or boron trifluoride etherate. The reaction of bifunctional isocyanates with polynitroaliphatic diols has been used to synthesize energetic polymers.33°... 

The reaction of 3-hydroxymethyl-3-methyloxetane (42) with dinitrogen pentoxide is an interesting example a short reaction time with 2.46 equivalents of dinitrogen pentoxide producing 3-(nitratomethyl)-3-methyloxetane (NIMMO) (43), an energetic polymer precursor. 

The polymers 1, 3 and 4 were 0-nitrated with nitric acid to give products containing nitrogen contents of 11.6 %, 19.9 % and 9.55 % respectively. Polymer 2, on the other hand, was nitrated with dinitrogen pentoxide in liquid carbon dioxide. Evaluations of these energetic polymers indicate that polymer 1 is a possible candidate for use in insensitive munitions. 

Primary nitramines have acidic protons and are able to undergo condensation reactions to form functionalized nitramines. These reactions are discussed in Section 5.13 because the products have potential application as energetic polymer precursors or find use for the synthesis of other explosives. 

Primary nitramines contain an acidic proton which enables them to behave as nucleophiles and undergo addition and condensation reactions. These reactions are extremely useful in two respects. Firstly, these reactions convert primary nitramino functionality into secondary nitramino functionality, which is no longer acidic and much more chemically stable. Secondly, these addition and condensation reactions can be used to prepare functionalized derivatives of polynitramines which can be used to synthesize energetic polymers and other explosive compounds. 

Michael addition reactions are particularly useful when linear aliphatic bis-nitramines are used because the products contain two terminal functional groups like in the diester (182). The terminal functionality of such products can be used, or modified by simple functional group conversion, to provide oligomers for the synthesis of energetic polymers such oligomers often use terminal alcohol, isocyanate or carboxy functionality for this purpose. 

Under aqueous conditions formaldehyde reacts with primary nitramines to form the corresponding methylol derivatives. The versatility of the terminal hydroxy group of these methylol derivatives is illustrated by their facile conversion to more reactive functional groups, like isocyanates, which can then be reacted with compounds containing hydroxy or carboxy functionality. Diisocyanates like (215), (216) and (217) have been reacted with various polyni-troaliphatic diols for the synthesis of energetic polymers. ... 

The chemistry of l,5-dinitroendomethylene-l,3,5,7-tetraazacyclooctane (239) (DPT) is interesting in the context of the nitramine products which can be obtained from its nitrolysis under different reaction conditions. The nitrolysis of DPT (239) with acetic anhydride-nitric acid mixtures in the presence of ammonium nitrate is an important route to HMX (4) and this has been discussed in Section 5.15.2. The nitrolysis of DPT (239) in the absence of ammonium nitrate leads to the formation of l,9-diacetoxy-2,4,6,8-tetranitro-2,4,6,8-tetraazanonane (248) the latter has found use in the synthesis of energetic polymers. 

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. ... 

The energetic nature of the azido group makes its incorporation into energetic polymers and binders very desirable. 3,3-Bis(azidomethyl)oxetane (BAMO) (28) and 3-azidomethyl-3-methyloxetane (AMMO) (33) are energetic monomers which on polymerization result in the energetic polymers poly[BAMO] (32) and Poly[AMMO] (34), respectively, both of which are under evaluation as potential energetic alternatives to HTPB in composite propellant formulations. ... 

The addition of crystalline oxidizers such as ammonium nitrate or potassium nitrate to nitrate esters or energetic polymers leads to the formation of composite ex-... 

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