Gadaleta Giovanni, De Gisi Sabino, Sorrentino Andrea, Sorrentino Luigi, Notarnicola Michele, Kuchta Kerstin, Picuno Caterina, Oliviero Maria
Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Politecnico di Bari, Via E. Orabona n. 4, I-70125 Bari, Italy.
Institute for Polymers, Composites and Biomaterials (IPCB), National Research Council (CNR), P.le E. Fermi n. 1, I-80055 Portici, Italy.
Materials (Basel). 2023 Jul 7;16(13):4869. doi: 10.3390/ma16134869.
The increased use of bioplastics in the market has led to their presence in municipal solid waste streams alongside traditional fossil-based polymers, particularly low-density polyethylene (LDPE), which bioplastics often end up mixed with. This study aimed to assess the impact of cellulose acetate plasticized with triacetin (CAT) on the mechanical recycling of LDPE. LDPE-CAT blends with varying CAT content (0%, 1%, 5%, 7.5%, and 10% by weight) were prepared by melt extrusion and analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, thermal analysis (thermogravimetric and differential scanning calorimetry), dynamic rheological measurements, and tensile tests. The results indicate that the presence of CAT does not significantly affect the chemical, thermal, and rheological properties of LDPE, and the addition of CAT at different levels does not promote LDPE degradation under typical processing conditions. However, the addition of CAT negatively impacts the processability and mechanical behavior of LDPE, resulting in the reduced quality of the recycled material. Thus, the presence of cellulose-based bioplastics in LDPE recycling streams should be avoided, and a specific sorting stream for bioplastics should be established.
市场上生物塑料使用量的增加，导致它们与传统的化石基聚合物一起出现在城市固体废物流中，特别是低密度聚乙烯（LDPE），生物塑料最终常常与之混合。本研究旨在评估用三醋精增塑的醋酸纤维素（CAT）对LDPE机械回收的影响。通过熔融挤出制备了具有不同CAT含量（按重量计0%、1%、5%、7.5%和10%）的LDPE-CAT共混物，并使用扫描电子显微镜、傅里叶变换红外光谱、热分析（热重分析和差示扫描量热法）、动态流变测量和拉伸试验进行分析。结果表明，CAT的存在不会显著影响LDPE的化学、热和流变性能，并且在不同水平添加CAT不会在典型加工条件下促进LDPE降解。然而，添加CAT会对LDPE的加工性能和机械性能产生负面影响，导致回收材料质量下降。因此，应避免在LDPE回收流中存在纤维素基生物塑料，并应建立专门的生物塑料分拣流程。
