Nanoparticles for energetic applications - formation and aggregation

The application of nanosized metallic particles as additive to propellants for rockets is at the laboratory and research level and except for burning rate modifiers not yet common for industrial applications. However, sometimes it is difficult to interpret experimentally determined particle size distribution functions of these metallic additions. It is the aim of this paper to give some support in answering questions posed by the interpretation of these experimental data. Properties of nanoparticles differ from those of conventional particles significantly. These different properties become apparent if one looks at particle size distributions stemming from different methods of synthesis and possibly the following aggregation processes. To understand these processes, it is necessary to describe the mechanisms causing size distributions and aggregation processes. This paper describes the influence of synthesis methods – especially looking at gas phase processes – and the thermodynamics rules governing aggregation processes. Understanding these processes, helps to interpret particle size distributions determined experimentally.