Chemical Recycling of Multiblock Copolymers to Polyols via Degradable Acetal Junctions

Developing polymer systems that combine robust mechanical performance with efficient chemical recyclability remains a significant challenge. Here, we developed a rapid, metal-free strategy for the synthesis of acetal-linked multiblock copolymers through acid-catalyzed coupling of hydroxyl-terminated polyols with divinyl ethers. This approach enabled the formation of high-molecular-weight PLLA/PPC multiblock copolymers within less than one hour under mild conditions, while systematic control of block length and composition allowed precise tuning of polymer architecture and mechanical properties. The strategy was further extended to other polyols, including PCL and PTMC, demonstrating its broad applicability. Importantly, the acetal linkages could be rapidly and selectively cleaved under mild acidic conditions to recover the parent polyols in high purity, and the recovered polyols were successfully reused to regenerate multiblock copolymers with comparable molecular weights and mechanical performance. These results establish a versatile platform for the development of structurally tunable and chemically recyclable multiblock polymer materials.