Surface grafting with energetic glycidyl azide polymer (GAP): an efficient way to process ultra fine aluminum powders

摘要

Aluminum powders are common contributions in explosives to increase detonation energy and work capacity. However, its application was limited by the following reasons: unstable, phobic to organic binders, and being difficult to disperse. To address all these issues at once, the ultrafine aluminum powders were treated by surface grafting with energetic glycidyl azide polymer (GAP) via consecutive TDI-GAP reactions. After surface grafting with GAP, the surface properties of the aluminum powders were significantly changed. The surface exhibits typical hydrophobic character and effectively prevents the aluminum from water oxidation under severe aging conditions (70 °C hot water). Therefore, it provides an efficient way to protect ultrafine aluminum powders and a potential route to prepare aluminum explosive formulations using ultrafine powders. The aluminum powders before and after surface grafting was characterized by FTIR, XPS, TG, SEM and surface contact angle measurement.