Synthesis of Several Azidoester Plasticizers and Investigation of Their Influence on the Reduction of Nitroglycerin Migration in Double Base Solid Propellants

Useing plasticizers in the formulation of solid propellants especially double-base solid propellants is inevitable. Double base propellants are composed of nitrocellulose (NC) polymer. Plasticizers increase flexibility and reduce viscosity and glass transition temperature. Energetic azido ester plasticizers are compatible with energetic binders in solid propellants. In this work, five different azido plasticizers as ethyleneglycol bisazidoacetate (EGBAA), trimethylene glycol bisazidoacetate (TMGAA), tetramethylene glycol bisazidoacetate (TMGBAA'), pentaerythritol tetrakis azidoacetate (PETKAA) and hyper-branched azidoester (HB-AZ) were successfully synthesized in two steps (formation of ester and azidation) with 55-92% yields. The synthesized azidoesters were identified by FT-IR and 1H-NMR spectroscopies. Study of the different parameters showed that pentaerythritol tetrakis azidoacetate and hyper-branched azidoester are more effective in reduction of the nitroglycerin migration than the other synthesized azidoesters.