School of Chemistry, University of Birmingham, Edgbaston B15 2TT, U.K.
Department of Chemistry, Mechanical Engineering and Materials Science, Biomedical Engineering and Orthopedic Surgery, Duke University, Durham, North Carolina, 20899, United States.
J Am Chem Soc. 2021 Oct 27;143(42):17510-17516. doi: 10.1021/jacs.1c06960. Epub 2021 Oct 15.
Stereochemistry provides an appealing handle by which to control the properties of small molecules and polymers. While it is established that stereochemistry in linear polymers affects their bulk mechanical properties, the application of this concept to photocurable networks could allow for resins that can accommodate the increasing demand for mechanically diverse materials without the need to significantly change their formulation. Herein, we exploit and stereochemistry in pre-resin oligomers to create photoset materials with mechanical properties and degradation rates that are controlled by their stereochemistry and molecular weight. Both the synthesis of stereopure ( or ) acrylate-terminated pre-polymers and the subsequent UV-triggered cross-linking occurred with a retention of stereochemistry, close to 100%. The stereochemistry of a 4 kDa oligomer within the resin enabled the tuning of the formulation to either a fast eroding, soft elastomer or a stiff plastic that is more resistant to degradation. These results demonstrate that stereochemistry is a powerful tool to modify the stiffness, toughness, and degradability of high-resolution, three-dimensional printed scaffolds from the same formulated ratio of components.
立体化学为控制小分子和聚合物的性质提供了一个有吸引力的手段。虽然已经确定线性聚合物中的立体化学会影响其整体机械性能，但将这一概念应用于光固化网络可以使树脂能够适应对机械性能多样化材料的日益增长的需求，而无需显著改变其配方。在这里，我们利用预聚物中的 和立体化学来创建具有机械性能和降解速率的光固化材料，这些性能和速率可以通过它们的立体化学和分子量来控制。立体纯（或）丙烯酸酯封端预聚物的合成以及随后的 UV 引发交联都保留了立体化学，接近 100%。树脂中 4 kDa 低聚物的立体化学使配方能够调节为快速降解的软弹性体或更能抵抗降解的硬塑料。这些结果表明，立体化学是一种强大的工具，可以从相同配方比的组件中修改高分辨率、三维打印支架的刚度、韧性和可降解性。
