Rotational molding is a technology of non-wastage forming of thin-walled products, mostly of thermoplastic polymers, consisting of sintering and subsequent plasticizing of polymer powders or micropellets in a rotating mold. Due to the possibility of one-stage shaping of large-size products with complex shapes that can be used in mechanical recycling processes, this technology has made it one of the most dynamically developing methods of processing polymer materials in recent years. The long-term exposure of the molded materials to elevated temperature, may cause the negative effects of thermal degradation on the shaped materials' structure. While the conducted scientific work allowed to confirm antioxidant and stabilizing effect of the impact of plant-derived fillers on selected polymers, the considerations so far have not addressed the issue of the influence of the molten state processing conditions of composites on the final effectiveness of their impact on the polymer matrix. The aim of the proposed project is to investigate the degradation phenomena occurring during hightemperature processing of polymer composites containing functional plant fillers and correlate them with the potential limitations of the effectiveness of the stabilizing effect of low-molecular compounds contained in them. Within in the project, the impact of the forming processes and preliminary preparation of polymer composites containing fillers rich in compounds with a confirmed stabilizing effect of polyolefin polymers, against unfavorable degradation phenomena that may lead to limiting their effectiveness in slowing down the aging processes of composites, will be undertaken. The multi-criteria assessment of the impact of process conditions will consider the correlation of the structure and properties of the final products with the measurements of low-molecular organic compounds formed as a result of thermal decomposition during technological processes. The benefits for PG resulting from the project include: - scientific publications with PG affiliation created as a result of the project, - development of the cooperation with the domestic and foreign scientific units (project realized in international cooperation), - prestige connected with the realization of grants financed by the National Science Center.