INFLUENCE OF FIBROUS FILLER ON THE MECHANISM AND KINETIC REGULARITIES OF CRYSTALLIZATION OF BASALT CONTAINING PLASTICS BASED ON POLYPROPYLENE RANDOM COPOLYMER

The paper presents the results of a study of the influence of fibrous basalt content on the regularity of composites crystallization based on polypropylene random copolymer. The studies were carried out using the method of stepwise dilatometry in the temperature range 20 – 210 °C. The dependence of the specific volume on temperature and filler content was studied, as a result of which the values of the temperature of the first-order phase transition, the glass transition temperature and the occupied specific volume were determined. An approximate estimate of the glass transition temperature of the composites was determined graphically by extrapolating the upper branch of the dilatometric curve to the intersection with the lower branch. It was possible to establish that as the basalt content increases up to 30 wt. %, a natural decrease in the specific volume or an increase in the density of the composites is observed. The regularity of free specific volume change from temperature was studied. It was shown that with the increase in fibrous basalt content, there is a regular decrease in free specific volume. The established regularity clearly indicates that in the process of crystallization and growth of crystalline formations, the filler is forced out into the interspherolitic amorphous space, which is characterized by a high content of free volume. A decrease in the value of free specific volume indicates that the filler fills the unoccupied volume in the amorphous space. In accordance with the Kolmogorov-Avrami equation, the kinetic regularity of crystallization of composites under isothermal conditions was studied, and the values of the generalized nucleation and growth constant of crystals K and the constant n were determined. It was found that with an increase in the content of fibrous basalt in the composition of random polypropylene, a change in the crystallization mechanism and the type of growth of crystalline structures is observed from three-dimensional spherulitic to one-dimensional - rod-shaped with the continuous formation of heterogeneous and homogeneous nucleation centers. For citation: Kakhramanov N.T., Nuraliyeva G.H., Martynova G.S., Kakhramanly Yu.N., Gadzhieva R.Sh. Influence of fibrous filler on the mechanism and kinetic regularities of crystallization of basalt containing plastics based on polypropylene random copolymer. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2025. V. 68. N 1. P. 85-92. DOI: 10.6060/ivkkt.20256801.7102.