The Structure of Nanofiller in Elastomeric Particulate-Filled Nanocomposites

Abstract

It is well-known [1, 2], that in particulate-filled elastomeric nanocomposites (rubbers) nanofiller particles form linear spatial structures (“chains”). At the same time in polymer composites, filled with disperse microparticles (microcomposites) particles (aggregates of particles) of filler form a fractal network, which defines polymer matrix structure (analog of fractal lattice in computer simulation) [3, 4, 5]. This results to different mechanisms of polymer matrix structure formation in microand nanocomposites. If in the first filler particles (aggregates of particles) fractal network availability results to “disturbance” of polymer matrix structure, that is expressed in the increase of its fractal dimension df [3], then in case of polymer nanocomposites at nanofiller contents change the value df is not changed and equal to matrix polymer structure fractal dimension [6]. As it has to been expected, composites indicated classes structure formation mechanism change defines their properties change, in particular, reinforcement degree. At present there are several methods of filler structure (distribution) determination in polymer matrix, both experimental [7, 8] and theoretical [3]. All the indicated methods describe this distribution by fractal dimension Dn of filler particles network. However, correct determination of any object fractal (Hausdorff) dimension includes three obligatory conditions. The first from them is the indicated above determination of fractal dimension numerical magnitude, which should not be equal to object topological dimension. As it is known [9], any real (physical) fractal possesses fractal properties within a certain scales range [10]. And at last, the third condition is the correct choice of measurement scales range itself. As it has been shown in papers [11, 12], the minimum range should exceed at any rate one self-similarity iteration. The present paper purpose is dimension Dn estimation, both experimentally and theoretically, and checking two indicated above conditions fulfillment, i.e. obtaining of nanofiller particles (aggregates of particles) network (“chains”) fractality strict proof in elastomeric nanocomposites on the example of particulate-filled butadiene-styrene rubber.