While a large number of chemically recyclable thermoplastics have been developed in recent years, technologically important thermoplastic elastomers (TPEs) that are not only bio-based and fully recyclable but also exhibit mechanical properties that can rival or even exceed those petroleum-based, non-recyclable polyolefin TPEs are critically lacking. The key challenge in developing chemically circular, bio-based, high-performance TPEs rests on the complexity of TPE’s block copolymer (BCP) structure involving block segments of different suitable monomers required to induce self-assembled morphologies responsible for performance as well as the control and monomer compatibility in their synthesis and the selectivity in their depolymerization. Here we demonstrate the utilization of bio-sourced δ-valerolactone (δVL) and its simple α-alkyl-substituted derivatives to produce all δVL-based polyester tri-BCP TPEs, which exhibit not only complete (closed-loop) chemical recyclability but also excellent toughness that is 2.5–3.8 times higher than commercial polyolefin-based TPEs. The visualized cylindrical morphology formed via crystallization-driven self-assembly in the new all δVL tri-BCP is postulated to contribute to the excellent TPE property.

虽然近年来开发了大量化学可回收热塑性塑料，但技术上重要的热塑性弹性体 (TPE) 不仅是生物基且完全可回收的，而且其机械性能可以与石油基非热塑性弹性体相媲美甚至超过这些热塑性弹性体。可回收的聚烯烃 TPE 严重缺乏。开发化学循环、生物基、高性能 TPE 的关键挑战在于 TPE 嵌段共聚物 (BCP) 结构的复杂性，涉及不同合适单体的嵌段片段，需要诱导负责性能和控制的自组装形态以及它们合成中的单体相容性和解聚中的选择性。在这里，我们展示了利用生物来源的 δ-戊内酯 (δVL) 及其简单的 α-烷基取代衍生物来生产所有基于 δVL 的聚酯三 BCP TPE，其不仅表现出完整的（闭环）化学可回收性，而且优异的韧性，比商用聚烯烃基 TPE 高 2.5-3.8 倍。新型全 δVL tri-BCP 中通过结晶驱动自组装形成的可视化圆柱形形态被认为有助于实现优异的 TPE 性能。