Zhao Yucheng, Rettner Emma M, Harry Katherine L, Hu Zhitao, Miscall Joel, Rorrer Nicholas A, Miyake Garret M
Department of Chemistry, Colorado State University, Fort Collins, CO 80523, USA.
School of Advanced Materials Discovery, Colorado State University, Fort Collins, CO 80523, USA.
Science. 2023 Oct 20;382(6668):310-314. doi: 10.1126/science.adh3353. Epub 2023 Oct 19.
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 () and low glass transition temperature (), making them suitable for use across diverse applications ( as high as 128°C and 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.
聚烯烃是生产的最重要且产量最大的塑料。不幸的是，塑料的大量使用以及缺乏有效的处置或回收选择造成了一场塑料垃圾灾难。在这项工作中，我们报告了一种方法，通过用钌介导的环辛烯开环易位聚合反应合成的硬软低聚结构单元构建多嵌段聚合物，来制备具有多种机械性能的化学可回收聚烯烃类材料。这些多嵌段聚合物表现出广泛的机械性能，涵盖弹性体、塑性体到热塑性塑料，同时兼具高熔点转变温度（）和低玻璃化转变温度（），使其适用于各种不同应用（熔点高达128°C，玻璃化转变温度低至 -60°C）。使用后，不同的塑料可以合并并有效地解构回基本的硬软结构单元，以便分离和再聚合，从而实现闭环回收过程。
