He Shaoyun, Hu Shikai, Wu Yaowen, Jin Ruiheng, Niu Zhihao, Wang Runguo, Xue Jiajia, Wu Sizhu, Zhao Xiuying, Zhang Liqun
Key Laboratory of Beijing City on Preparation and Processing of Novel Polymer Materials, Beijing University of Chemical Technology, Beijing 100029, China.
Beijing Engineering Research Center of Advanced Elastomers, Beijing University of Chemical Technology, Beijing 100029, China.
Biomacromolecules. 2022 Oct 10;23(10):4192-4202. doi: 10.1021/acs.biomac.2c00662. Epub 2022 Sep 8.
Polylactic acid (PLA) has received increased attention in the development of shape-memory polymers and biomedical materials owing to its excellent physical properties and good biocompatibility and biodegradability. However, the inherent brittleness and high shape-recovery temperature of this material limit its application in the human body. Herein, we fabricated a PLA-based thermoplastic polyurethane (PLA-TPU) prepared from modified PLA-diol, dicyclohexylmethane-4,4'-diisocyanate, and 1,4-butanediol to solve the limitations of pure PLA. The glass transition temperature () of the designed TPU can be tailored from 6 to 40.5 °C by adjusting the content of hard segments or molecular weight of soft segments. The shape of the designed TPU can be fixed at room temperature and recovered at temperatures above 37 °C. Moreover, the prepared PLA-TPUs exhibited recyclability, three-dimensional printing capability, non-cytotoxicity, blood compatibility, and biodegradability. The shape of PLA-TPU/nano-FeO composites can be recovered by exposure to near-infrared light. These results collectively indicate that PLA-TPUs and their composites may have potential applications as intelligent flexible medical scaffolds for surgical and medical implantation equipment.
聚乳酸（PLA）因其优异的物理性能、良好的生物相容性和生物降解性，在形状记忆聚合物和生物医学材料的开发中受到了越来越多的关注。然而，这种材料固有的脆性和较高的形状恢复温度限制了其在人体中的应用。在此，我们制备了一种基于聚乳酸的热塑性聚氨酯（PLA-TPU），它由改性聚乳酸二醇、二环己基甲烷-4,4'-二异氰酸酯和1,4-丁二醇制成，以解决纯聚乳酸的局限性。通过调整硬段含量或软段分子量，所设计的热塑性聚氨酯的玻璃化转变温度（）可在6至40.5°C之间进行调整。所设计的热塑性聚氨酯的形状可在室温下固定，并在高于37°C的温度下恢复。此外，制备的PLA-TPU具有可回收性、三维打印能力、无细胞毒性、血液相容性和生物降解性。PLA-TPU/纳米FeO复合材料的形状可通过近红外光照射恢复。这些结果共同表明，PLA-TPU及其复合材料作为用于手术和医疗植入设备的智能柔性医疗支架可能具有潜在应用。
