Oxidation and combustion studies of polyacrylamide constructed high energy aluminum-based reactive fuel

Aluminum (Al) powder is easy to agglomerate in the combustion process, thereby inhibiting its continuous combustion, which results in the reduction of combustion intensity and combustion efficiency directly. Polyacrylamide (PAM), as a high molecular weight polymer, has the potentiality to react with Al via many aromatic compounds produced from its cracking. In this study, a solvent/non-solvent method was used to successfully coat micron-sized Al particles with PAM to form the [email protected]μAl, aiming to improve their ignition and combustion properties. The results show that PAM and μAl interact in the [email protected]μAl samples, and PAM inhibits the generation of oxide layer on the Al surface during the combustion process, while the presence of Al affects the thermal behavior of PAM. The combustion process of the [email protected]μAl samples includes three stages: explosive combustion, transitional combustion, and stable combustion. Compared with the monolithic Al, the [email protected]μAl samples have a shorter ignition delay and greater combustion intensity, and the oxide shell on the surface of Al particles is more easily broken, which is beneficial to the internal molten Al overflow. In addition, PAM can effectively inhibit the agglomeration behavior between Al particles during the combustion process. In particular, the best ignition and combustion performance of the [email protected]μAl samples appears when the mass percentage of PAM is 7 wt.%.