Design of dynamic polythiourethane adhesives via molecular orbital modulation: An efficient strategy to recovery energetic composites via mild solvolysis

The emerging thiourethane dynamic chemistry provides a sustainable alternative to conventional polyurethane systems. By employing frontier molecular orbital (FMO) analysis, the molecular and electronic properties of polythiourethane (PTU) were evaluated, providing unique insights into their chemical reactivity and dissociation ability. Guided by theoretical simulations, a series of crosslinked polyurethanes were synthesized and evaluated for thermal stability, mechanical performance, and reprocessability. The application of PTU adhesives in Nitrate Ester Plasticized Polyether (NEPE) propellants does not compromise burning performance and enables the efficient recovery of valuable components via mild solvolysis. Separation and revovery of the involved energetic components were readily achieved, highlighting PTU polymers as promising candidates for recyclable propellants. This method achieves safe recovery of energetic components from composite solid propellants, establishing innovative pathways for sustainable aerospace technology development.