Development of Triazole Cure System

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. Fluorochem, Inc., has carried out investigations of the synthesis of the acetylene and azide components.Preliminary polymerization studies resulted in gumstocks with good mechamical properties in qualitative tests. The objective of the Phase II program is to develop the synthetic and polymerization procedures to enable commercialization of the binders.BENEFITS: 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 analternate to polyurethanes.