Synthesis of linear multi-block copolymers and their application in plastic recycling and modification

Due to the continuous rise in plastic production and consumption, environmental pollution caused by plastic waste has become increasingly severe, posing a pressing global challenge. In plastic recycling, efficient separation of different polymer components remains a key technical bottleneck. Multi-block copolymers, as functional materials capable of promoting compatibility between immiscible polymers, exhibit significant potential for enabling high-value recycling of mixed plastics. However, their widespread application is hindered by complex synthesis procedures and challenges in precise structural control. In this study, multi-block copolymer materials were successfully synthesized through the copolymerization of commercially available macromonomers containing backbone olefin double bonds with cycloolefin monomers, followed by hydrogenation. When used as compatibilizers in mechanical recycling, these materials significantly enhance the interfacial compatibility of mixed plastics, leading to a marked improvement in the tensile toughness of the recycled products. Furthermore, the developed multi-block copolymers can effectively modulate the surface properties of polyolefins, thereby improving their barrier performance against water and oil. This work presents a novel technical pathway for the efficient resource recovery of mixed plastics and the functional modification of polyolefin materials, demonstrating broad application prospects.