Structure of a metal-filled film polymer composite near the percolation threshold

The aggregation of metal particles in a polymer matrix curing near the perc olation threshold was investigated. It was shown that the aggregation proce ss proceeds simultaneously by several mechanisms, thus resulting in a wide size spectrum of aggregates formed in a system during the curing. An interr elation exists between the size and the structure of aggregates. The charac teristic scale of a system, which corresponded to the correlation length, w as established. The correlation length was shown to be related to the curin g temperature and the presence of fluctuations in the initial concentration of metal particles in the sample bulk. The applicability of a fractal appr oach to the description of the system studied was confirmed; in particular, the coincidence of the fractal dimensions of the percolation cluster and t he aggregates in a composite was established.