School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen, 518172, P. R. China.
School of Life Science, Zhengzhou University, Zhengzhou, 450001, P. R. China.
Adv Mater. 2023 May;35(20):e2210092. doi: 10.1002/adma.202210092. Epub 2023 Mar 31.
Elastomers have many industrial, medical and commercial applications, however, their huge demand raises an important question of how to dispose of the out-of-service elastomers. Ideal elastomers that are concurrently tough, recyclable, and degradable are in urgent need, but their preparation remains a rigorous challenge. Herein, a polycaprolactone (PCL) based polyurethane elastomer is designed and prepared to meet this demand. Owing to the presence of dynamic coordination bond and the occurrence of strain-induced crystallization, the obtained elastomer exhibits a high toughness of ≈372 MJ m and an unprecedented fracture energy of ≈646 kJ m , which is much higher than natural rubber (≈50 MJ m for toughness and ≈10 kJ m for fracture energy). In addition, the elastomer can be recycled at least three times using solvent without losing its mechanical properties and can be degraded by lipase in ≈2 months. Finally, biological experiments demonstrate that the elastomer possesses good biocompatibility and can facilitate wound healing in mice when used as sutures. It is believed that the obtained elastomer meets the requirements for next-generation elastomers and is expected to be used in emerging fields such as biomedicine, flexible electronics, robotics and beyond.
弹性体具有许多工业、医疗和商业应用，然而，它们的巨大需求提出了一个重要的问题，即如何处理废弃的弹性体。同时具有韧性、可回收性和可降解性的理想弹性体急需开发，但它们的制备仍然是一个严峻的挑战。在此，设计并制备了一种基于聚己内酯（PCL）的聚氨酯弹性体以满足这一需求。由于存在动态配位键和应变诱导结晶的发生，所得到的弹性体表现出高达约 372 MJ m 的高韧性和约 646 kJ m 的前所未有的断裂能，远高于天然橡胶（韧性约为 50 MJ m ，断裂能约为 10 kJ m ）。此外，该弹性体可以使用溶剂至少回收三次而不损失其机械性能，并且可以在大约 2 个月内被脂肪酶降解。最后，生物学实验表明，弹性体具有良好的生物相容性，用作缝线时可促进小鼠伤口愈合。相信所得到的弹性体满足下一代弹性体的要求，并有望在生物医学、柔性电子、机器人等新兴领域得到应用。
