biostudies-literatureZhao YNIGMS NIH HHS310-314https://www.ebi.ac.uk/biostudies/studies/S-EPMC10710102biostudies-literatureUnknown382(6668)Polyolefins are the most important and largest volume plastics produced. Unfortunately, the enormous use of plastics and lack of effective disposal or recycling options have created a plastic waste catastrophe. In this work, we report an approach to create chemically recyclable polyolefin-like materials with diverse mechanical properties through the construction of multiblock polymers from hard and soft oligomeric building blocks synthesized with ruthenium-mediated ring-opening metathesis polymerization of cyclooctenes. The multiblock polymers exhibit broad mechanical properties, spanning elastomers to plastomers to thermoplastics, while integrating a high melting transition temperature (<i>T</i>_m) and low glass transition temperature (<i>T</i>_g), making them suitable for use across diverse applications (<i>T</i>_m as high as 128°C and <i>T</i>_g as low as -60°C). After use, the different plastics can be combined and efficiently deconstructed back to the fundamental hard and soft building blocks for separation and repolymerization to realize a closed-loop recycling process.Science (New York, N.Y.)Chemically recyclable polyolefin-like multiblock polymers.PMC10710102R35 GM144356Miyake GMHu ZHarry KLRettner EMMiscall JRorrer NAZhao YfalseChemically recyclable polyolefin-like multiblock polymers.Polyolefins are the most important and largest volume plastics produced. Unfortunately, the enormous use of plastics and lack of effective disposal or recycling options have created a plastic waste catastrophe. In this work, we report an approach to create chemically recyclable polyolefin-like materials with diverse mechanical properties through the construction of multiblock polymers from hard and soft oligomeric building blocks synthesized with ruthenium-mediated ring-opening metathesis polymerization of cyclooctenes. The multiblock polymers exhibit broad mechanical properties, spanning elastomers to plastomers to thermoplastics, while integrating a high melting transition temperature (<i>T</i>_m) and low glass transition temperature (<i>T</i>_g), making them suitable for use across diverse applications (<i>T</i>_m as high as 128°C and <i>T</i>_g as low as -60°C). After use, the different plastics can be combined and efficiently deconstructed back to the fundamental hard and soft building blocks for separation and repolymerization to realize a closed-loop recycling process.2023-01-01T00:00:00Z2023 Oct2025-04-18T13:09:26.215Z2025-04-06T22:42:53.286ZS-EPMC107101023785659810.1126/science.adh3353