Wyderkiewicz Wiktor, Gogolewski Robert, Miedzianowska-Masłowska Justyna, Szustakiewicz Konrad, Masłowski Marcin
Institute of Polymer and Dye Technology, Lodz University of Technology, Stefanowskiego 16, 90-537 Lodz, Poland.
CDM Packaging, Cegielniana 7, 95-054 Ksawerów, Poland.
Polymers (Basel). 2025 Aug 30;17(17):2368. doi: 10.3390/polym17172368.
The recycling of polypropylene (PP) packaging films modified with biobased additives: biochar derived from the pyrolysis of natural fibers and diatomaceous earth was investigated. The aim was to assess the impact of these modifiers on the processing, rheological, mechanical, and thermal properties of the recycled material. The processing behavior was evaluated through extrusion with granulation to determine industrial applicability. Rheological properties, including viscosity and melt flow index (MFI), were measured to characterize flow behavior. Mechanical performance was assessed through tensile strength, hardness, three-point bending, and impact resistance tests. Thermal properties were analyzed using thermogravimetric analysis (TGA), Vicat softening temperature (VST), and differential scanning calorimetry (DSC). The results demonstrate that incorporating biochar and diatomaceous earth can modify and, in selected cases, enhance the processing and performance characteristics of recycled PP films, though their impact on thermal behavior is parameter-specific. While diatomaceous earth slightly increased the onset of thermal degradation (T), both fillers caused a slight decrease in the VST, indicating reduced heat resistance under load. Diatomaceous earth was found to effectively improve stiffness and impact strength, while biochar reduced viscosity and promoted finer crystalline structures. Both additives acted as nucleating agents, increasing crystallization temperatures, with diatomaceous earth additionally delaying thermal degradation onset. These findings highlight the potential of using sustainable, waste-derived additives in polymer recycling, supporting the development of environmentally responsible materials within circular economy frameworks.
对用生物基添加剂改性的聚丙烯（PP）包装薄膜进行回收利用的研究：这些添加剂包括天然纤维热解产生的生物炭和硅藻土。目的是评估这些改性剂对回收材料的加工、流变、机械和热性能的影响。通过造粒挤出评估加工行为，以确定其工业适用性。测量流变性能，包括粘度和熔体流动指数（MFI），以表征流动行为。通过拉伸强度、硬度、三点弯曲和抗冲击性测试评估机械性能。使用热重分析（TGA）、维卡软化温度（VST）和差示扫描量热法（DSC）分析热性能。结果表明，加入生物炭和硅藻土可以改变并在某些情况下增强回收PP薄膜的加工和性能特性，尽管它们对热行为的影响因参数而异。虽然硅藻土略微提高了热降解起始温度（T），但两种填料都使维卡软化温度略有降低，表明负载下耐热性降低。发现硅藻土能有效提高刚度和抗冲击强度，而生物炭降低粘度并促进形成更细的晶体结构。两种添加剂都作为成核剂，提高结晶温度，硅藻土还额外延迟了热降解起始温度。这些发现突出了在聚合物回收中使用可持续的、源自废料的添加剂的潜力，支持在循环经济框架内开发对环境负责的材料。
