Closed-loop recycling and utilization of waste hydroxyl-terminated polybutadiene solid propellant

How to reasonably and effectively deal with waste solid propellants and promote the recycling of propellants has become an important problem to be solved urgently in the global aerospace and military fields. Unlike the traditional incineration and landfill methods, in this paper, periodate (H5IO6) oxidative cracking method was applied for the first time to the degradation and recovery of waste hydroxyl-terminated polybutadiene (HTPB) based propellant. The method not only recovers 99 % of aluminum powder (Al) and 80 % of ammonium perchlorate (AP) but also reprocesses the degradation products of the binder matrix into an oligomeric cross- linking agent (OCA). Compared with the small molecule crosslinking agent, OCA can make the elastomer have better flexibility when OCA is used in the preparation of HTPB based polyurethane elastomer. The tensile strength of the elastomer is 1.37 MPa and the elongation at break is 375 %. In short, this strategy is not only safe and efficient, but also truly realizes the closed-loop recovery of waste HTPB based propellant.