Synthesis of Polyacetylene Curing Agents

"Composite propellants and explosives typically consist of solid oxidizers, metallic fuels, and rubbery binders that provide the needed mechanical properties. Most binder systems are cured by the formation of urethane linkages by the reaction of oligomericdiols with diisocyanates or triisocyanates. A variety of available diols and isocyanates enables the formulation of binders with optimum physical properties for specific systems.New energetic ingredients are being investigated that have chemical properties incompatible with the polyurethane system. Limited investigations have been conducted of an alternative cure system based in the reaction azido-terminated oligomers with di- orpolyacetylenes to form polytriazoles. It is anticipated that azides and acetylenes will be not be affected by the reactivity of the new ingredients. The acetylenic components, however, were obtained only on a gram scale, and larger quantities are needed.The objective of the Phase I program is to synthesize 100 to 450 g batches of each of the following acetylenic compounds: (1) 1,4 -di(cyanoethynyl)-benzene, (2) dipropargyl terephthalate, (3) tripropargyl mesitylate, and (4)dodecane-2,11-dione-1,12-dipropiolate. The major DOD use is as components for rocket propellant binders to enable the use of energetic ingredients incompatible with polyurethanes. The result is improved performance, i.e., range and payload. Commercial markets include use as an altern