Amine bonding agents in polyester binders

Abstract

Amine salts which are adducts of an ammonium ion donor selected from ammom perchlorate, ammonium sulfate, ammonium formate, and equal molar mixture of ammonium perchlorate and ammonium formate and cyanoethyl substituted tetraethylene pentamine (TEPAN) or the glycidol reaction product of cyanoethyl substituted tetraethylene pentamine (TEPANOL) are employed as a bonding agent in a solid propellant composition employing a polyester binder of polydiethyleneglycoladipate. Unlike hydroxy-terminated polybutadiene wherein a bonding agent is solubilized and still can function as a bonding agent for inorganic ammonium oxidizer salts in the propellant matrix, polyester binders that solubilize the bonding agent renders the bonding agent ineffectual as a bonding agent. Therefore, with a polyester binder it was found that the bonding agent could not be soluble in the prebinder to be effective in improving mechanical properties. It was, however, necessary for the bonding agent to be finely dispersed since it is driven to the inorganic oxidizer salt surfaces where it homopolymerizes around or reacts with a second reactant, usually the propellant curative to form a shell which will subsequently react with the binder thus chemically reinforcing the binder/inorganic oxidizer salt matrix.