The self‐healing capability of Hydroxyl Terminated Polybutadiene (HTPB) based polyurethane binder via Ring Opening Metathesis Polymerization(ROMP) is reported. Microencapsulated healing agent Dicyclopentadiene (DCPD) and wax protected Ru‐based Grubbs catalyst were incorporated in binder matrix (i.e,HTPB) uniformly to heal the cracks. These healing agents were also incorporated into HTPB matrix individually to check healing properties on their own and thereafter cured for five days. The incorporation of these healing agents in binder matrix did not affect the curing of matrix. It was found out that cuts when applied to the matrix were self‐healed at room temperature. Mechanical testing have revealed that around 50 % of tensile strength was regained in the healed specimen.

Hydroxyl Terminated Poly Butadiene (HTPB) based polyurethanes are widely used as polymeric binders in energetic formulations & other applications. Hence, customization in structure of HTPB has been investigated to improve their mechanical and thermal properties. Herein, modification of HTPB polyurethane has been reported in this paper by incorporating 2-hydroxy-3, 5-dinitropyridine (DNP) covalently into the HTPB polyurethane matrix in order to exhibit selfhealing properties. The functionalized polyurethane concurrently displays self-healing capability via metal-ligand interac-tion and also catalytic activity towards thermal decomposition of Ammonium Perchlorate (AP). The self-healing ability was observed by Optical Microscope and up to 96 % healing efficiency was observed by UTM analysis. Further, the catalytic activity was observed with thermal decomposition of Ammonium Perchlorate performed by DSC shows lowering in decomposition temperature by 73 °C. By involving the selfhealing and catalytic activity through single moiety in the polymer chain, this two-in-one strategy allows to produce advance binders for energetic formulations.

The burning rate of composite rocket propellant is a principal ballistic property that is considered while designing the rocket motor. Carbon bonded materials such as CNT(carbon nanotubes), fullerene, graphene, etc. due to their high surface area have exhibited promising results as burn rate modifiers in a propellant. Apart from enhancing the burn rate, unlike their inorganic counterparts, they are combustible and contribute towards energy output. Herein, we report a spinel structure CuFe 2 O 4 decorated Graphene Oxide nanocomposite as novel burn rate modifier (BRM) in propellant composition. By incorporating 0.6 % of this burn rate modifier to the propellant remarkable improvement in burn rate by 61 % was observed.

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