ВПЛИВ КАРБОНАТУ КАЛЬЦІЮ НА ПРОЦЕС БАГАТОРАЗОВОЇ ПЕРЕРОБКИ ПВХ КОМПОЗИТІВ

The influence of calcium carbonate filler on the rheological and physicomechanical properties of the obtained rigid PVC compositions during the cyclic processing process was investigated. In order to determine the optimal parameters of modifying additives, a series of experiments was conducted with the variation of their concentrations and the analysis of changes in the melt flow index (MFR), tensile strength, relative elongation and impact toughness during five processing cycles. The results show that the introduction of 15-20 wt. parts of calcium carbonate increases thermal stability and ensures the preservation of mechanical properties, but exceeding this value negatively affects the impact strength and limits the reuse of the material. The results obtained are a significant contribution to the development of technologies for multiple PVC recycling in the conditions of a cyclical economy and allow improving the formulations of compounds for industrial use.