Combustion inhibitor based on an aliphatic polyurethane elastomer for a propellant, and block coated with this inhibitor

摘要

The invention relates to a combustion inhibitor composition intended to cover partly the surface of blocks of double-base propellant. The inhibitor composition of the invention includes an aliphatic polyurethane obtained by the reaction of at least one polyisocyanate with a mixture of at least one polyetherpolyol containing at least three hydroxy groups per molecule and at least one polymer containing two hydroxy groups per molecule. This difunctional polymer is chosen from lactone polymers, such as poly- epsilon -caprolactone and polytetrahydrofuran. The inhibitor composition may also contain gasifiable fillers and an aliphatic plasticizer. The composition has good discreteness properties, while retaining excellent mechanical properties. The present invention has particular application in the field of solid weapon propulsion.