Small particles such as clay minerals, because of its large surface area to volume ratio and their high chemical activity on the particle surface, when added to composites affects (and often enhances) the physical, chemical and mechanical properties of materials immensely. As a result, there is a need to develop a method of characterizing these particles individually. However, physical dispersion of these particles can be very difficult, since they tend to agglomerate to reduce the high surface energy. Disperants of various sorts could be used to disperse/stabilize the system, but they could compromise/damage the integrity of the inherent state of these small particles. This paper presents a comparison study of preparing/dispersing small clay particles for electron microscopy research, and also represents the first report of cryo-microscopy of clay minerals.
Two types of smectites, namely a montmorillonite with cation exchange capacity (CEC= 140) and a saponite (CEC=42) were used for this study.