Study of Fractal Characteristics and Structure of the Filler Aggregates in Polymer Dispersions

摘要

Phase structure and morphology of nanosized-particle films, based on the monodisperse polystyrene filled with technically pure carbon KhM-72, are studied. To reveal the filler particles distribution in the polymer samples, their surface was etched in microwave plasma of oxygen discharge. The etched surface was analyzed by TEM, using an EM-301 microscope (Philips) with one-step carbon-platinum replicas. The system morphology was studied by determining the fractal dimension. The dependence of the fractal dimension on the number of the disperse phase particles was investigated. It is shown that at different filler concentrations the aggregates form by different mechanisms: the primary associates form by the cluster-particle mechanism; the secondary ones, by the cluster-cluster mechanism. At the filler concentration >15 percent, extensive networks with differently sized defects form in the system.