Effect of Polymeric Surfactants on the Behavior of Polycrystalline Materials with Special Reference to Ammonium Nitrate

摘要

The particles of inorganic polycrystalline materials, for example, the nitrates of potassium, sodium, and ammonium in either their spherical or granular forms, consist of aggregations of irregular forms of crystals, which provide free variable space between the crystals. During the formation and growth of crystals below the crystallization temperature, a progression of crystal growth occurs during both cooling and drying stages. The study discussed here relates to the effect of some sulfonated polymeric surfactants on the changes of crystal growth pattern in ammonium nitrate particles. Atomic force microscopy studies on the particles confirm a unique associated migration of water-bound polymeric additives during crystallization, which limits the growth of the individual crystals to almost unit cell dimensions by controlling the overall crystallization pattern.