Poon Kam C, Gregory Georgina L, Sulley Gregory S, Vidal Fernando, Williams Charlotte K
Chemistry Research Laboratory, Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK.
Adv Mater. 2023 Sep;35(36):e2302825. doi: 10.1002/adma.202302825. Epub 2023 Jul 23.
Utilizing carbon dioxide (CO ) to make polycarbonates through the ring-opening copolymerization (ROCOP) of CO and epoxides valorizes and recycles CO and reduces pollution in polymer manufacturing. Recent developments in catalysis provide access to polycarbonates with well-defined structures and allow for copolymerization with biomass-derived monomers; however, the resulting material properties are underinvestigated. Here, new types of CO -derived thermoplastic elastomers (TPEs) are described together with a generally applicable method to augment tensile mechanical strength and Young's modulus without requiring material re-design. These TPEs combine high glass transition temperature (T ) amorphous blocks comprising CO -derived poly(carbonates) (A-block), with low T poly(ε-decalactone), from castor oil, (B-block) in ABA structures. The poly(carbonate) blocks are selectively functionalized with metal-carboxylates where the metals are Na(I), Mg(II), Ca(II), Zn(II) and Al(III). The colorless polymers, featuring <1 wt% metal, show tunable thermal (T ), and mechanical (elongation at break, elasticity, creep-resistance) properties. The best elastomers show >50-fold higher Young's modulus and 21-times greater tensile strength, without compromise to elastic recovery, compared with the starting block polymers. They have wide operating temperatures (-20 to 200 °C), high creep-resistance and yet remain recyclable. In the future, these materials may substitute high-volume petrochemical elastomers and be utilized in high-growth fields like medicine, robotics, and electronics.
通过二氧化碳（CO₂）与环氧化物的开环共聚反应（ROCOP）来制备聚碳酸酯，可实现CO₂的增值利用与回收，并减少聚合物制造过程中的污染。催化领域的最新进展使得制备具有明确结构的聚碳酸酯成为可能，并能与生物质衍生单体进行共聚；然而，所得材料的性能尚未得到充分研究。在此，我们描述了新型的源自CO₂的热塑性弹性体（TPE），以及一种通用方法，该方法无需重新设计材料即可提高拉伸机械强度和杨氏模量。这些TPE在ABA结构中，将包含源自CO₂的聚碳酸酯（A嵌段）的高玻璃化转变温度（Tg）无定形嵌段与源自蓖麻油的低Tg聚（ε-癸内酯）（B嵌段）相结合。聚碳酸酯嵌段用金属羧酸盐进行选择性官能化，其中金属为Na(I)、Mg(II)、Ca(II)、Zn(II)和Al(III)。这些金属含量<1 wt%的无色聚合物具有可调节的热性能（Tg）和机械性能（断裂伸长率、弹性、抗蠕变性）。与起始嵌段聚合物相比，性能最佳的弹性体的杨氏模量提高了50倍以上，拉伸强度提高了21倍，且不影响弹性回复率。它们具有较宽的工作温度范围（-20至200°C），高抗蠕变性，并且仍可回收利用。未来，这些材料可能会替代大量使用的石化弹性体，并应用于医学、机器人技术和电子等高增长领域。
