Shock and High Strain Rate Characterization of HTPB with Varying Plasticizer

Hydroxy-terminated polybutadiene (HTPB) has long been used as a binder in propellants and explosives. However, cured HTPB rubbery polyurethanes have not been characterized in a systematic fashion as function of plasticizer content. In this study, four isocyanate-cured HTPB variants with different amounts of plasticizer have been formulated. The materials were characterized using dynamic mechanical analysis and quasi-static and dynamic compression experiments. Additionally, the shock Hugoniot was measured on the two extremes of the material -- no plasticizer and maximum plasticizer. The properties of the HTPB were predicted using the Porter-Gould model for polymers.