부산대학교 도서관

As environmental pollution problems become serious due to the increase in plastic production and disposal, the importance of recycling is being emphasized. Low-density polyethylene (LDPE) and Polyethylene terephthalate (PET) are prominent polymer materials widely used in various applications, including packaging materials. Currently, the global recycling rate remains at 9%, primarily due to the complexities associated with recycling multi-component products. For mixed plastic waste or multi-component plastics, the individual plastic components cannot be efficiently physically separated. They also exhibit weak interfacial adhesion when melt reprocessed, resulting in poor mechanical properties.In this study, eco-friendly strategies are presented to enhance the miscibility of post-consumer PET and LDPE blends. A mechanochemical process, utilizing robust compression∙shear∙mechanical forces, is introduced to enhance interfacial affinity. As a result, a novel covalent bond, such as a block copolymer, is formed, leading to entanglement or co-crystallization with homopolymer domains. This strengthens the interface and reduces the possibility of failure by chain pullout. Specifically, the impact strength of the blends improved by 112% through toughening effect, with PET particles uniformly dispersed in small sized within the LDPE matrix. This sustainable mechanochemical process is expected to serve as a strategic approach to increase recycling rates by enhancing compatibility among various polymer materials.