Viscoelastic Behaviour of Solid Propellants based on Various Polymeric Binders

Abstract

The dynamic mechanical properties of different binders and corresponding propellants are studied in terms of storage modulus and loss tangent. The binders investigated are HTPB, CTPB, PBAN, HEF-20 and ISRO polyol. The viscoelastic behaviour is investigated using Rheovibron viscoelastometer at 35 Hz covering a wide temperature range (-100 degree centigrade to 100 degree centigrade). The properties of the binder and corresponding propellant are compared in terms of parameters, tan delta/sub max/, T/sub g/ and the trend of their master relaxation modulus curves. It is found that polybutadiene binders exhibit lowest T/sub g/ (around -60 degree centigrade) and ISRO polyol the highest (near -20 degree centigrade). The propellants have higher moduli than the binders at any temperature. The master relaxation modulus curve is influenced by the type of propellant.