CURRENT TRENDS AND INNOVATIVE APPROACHES IN POLYMER WASTE RECYCLING TECHNOLOGIES
DOI:
https://doi.org/10.30857/2786-5371.2026.4.6Keywords:
polymer waste, mechanical recycling, polyethylene, thermomechanical degradationAbstract
Purpose. To systematize current approaches to the mechanical recycling of polymer waste, identify the main factors affecting the quality of secondary raw materials, and summarize technological solutions aimed at preserving and restoring their functional properties.
Methodology. An analytical review of scientific publications on the identification, sorting, cleaning, separation, mechanical processing, and stabilization of polymer waste was conducted. Current understanding of the mechanisms of thermomechanical degradation and methods for controlling the molecular weight, rheological, mechanical, and thermal characteristics of recycled polymers was summarized.
Findings. It was established that the quality of recycled polymers is determined by the composition and degree of contamination of the waste, the efficiency of sorting and cleaning, as well as the parameters of reprocessing. Thermomechanical degradation may involve polymer chain scission or branching, changes in molecular weight, and deterioration of mechanical and rheological properties. Current approaches to improving the quality of recycled polymers were systematized, including high-precision sorting, advanced cleaning and melt filtration, restabilization, compatibilization, reactive extrusion, functional modification, and process digitalization.
Originality. A systematic view of mechanical recycling as a set of interconnected technological operations that sequentially determine the quality of secondary polymer raw materials was developed. Approaches to controlling degradation processes and restoring the properties of recycled polymers were summarized, and an integrated sequence of their preparation and processing was proposed: identification, sorting, cleaning, stabilization, modification, extrusion, filtration, and quality control.
Practical value. The results can be used to select and optimize mechanical recycling technologies for polyolefins and other polymers, improve cleaning and stabilization processes, control the quality of secondary raw materials, and expand their potential for further applications. The proposed systematic approach contributes to reducing material and resource losses and improving the efficiency of secondary polymer utilization in accordance with the principles of the circular economy.
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