Abstract:

Backgrounds. The regularities of the structure formation of polymer microcomposite materials during their cooling from the melt are established. Objective. The aim of the work is to study the crystallization features of microcomposites based on a polypropylene matrix with a filler in the form of aluminum microparticles. Methods. The research technique includes two stages: the experimental receipt of crystallization exotherms and, based on them, the theoretical determination of the main characteristics of the structure formation process. Results. The patterns of composites crystallization were studied in a wide range of changes in the melt cooling rate and the mass fraction of filler for microcomposites obtained by two methods, the first of which is based on mixing the components in dry form, the second – in the polymer melt. An analysis of the structure formation mechanisms of the studied composites at the nucleation stage and at the stage of structures formation in the melt volume is made. Conclusions. It is shown that at the first of the indicated stages, a planar and volumetric crystallization mechanism is realized with some prevalence of the volumetric one. At the second stage, when using the method of producing composites, based on the mixing of components in a dry form, a tense matrix mechanism takes place; when implementing the method of mixing components in a polymer melt, the structure formation mechanism depends on the mass fraction of the filler.

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