Nancy E. and Peter C. Meining School of Biomedical Engineering, Cornell University, 277 Kimball Hall, Hollister Drive 134, Ithaca, New York 14853, United States.
School of Dental Medicine, University of Pittsburgh, 335 Sutherland Drive, 522 Salk Pavilion, Pittsburgh, Pennsylvania 15260, United States.
ACS Biomater Sci Eng. 2020 Feb 10;6(2):852-864. doi: 10.1021/acsbiomaterials.9b01357. Epub 2020 Jan 13.
Polyurethane is an important biomaterial with wide applications in biomedical engineering. Here, we report a new method to make an azido-functionalized polyurethane prepolymer with no need of postmodification. This prepolymer can easily form stable porous elastomers through click chemistry for cross-linking, instead of using a toxic polyisocyanate. The mechanical properties can be modulated by simply adjusting either the prepolymer concentrations or azido/alkyne ratios for cross-linking. Young's modulus therefore varies from 0.52 to 2.02 MPa for the porous elastomers. When the azido-functionalized polyurethane elastomer is made with a compact structure, Young's modulus increases up to 28.8 MPa at 0-15% strain. The strain at break reaches 150% that is comparable to the commercially resourced Nylon-12. Both the porous and compact elastomers could undergo reversible elastic deformations for at least 200 and 1000 cycles, respectively, within 20% strain without failure. The material showed a considerable stability against erosion in a basic solution. In vivo biocompatibility study demonstrated no degradation by subcutaneous implantation in mice over 2 months. The implant induced only a mild inflammatory response and fibrotic capsule. This material might be useful to make elastomeric components of biomedical devices.
聚氨酯是一种重要的生物材料，在生物医学工程中有广泛的应用。在这里，我们报告了一种新的方法，可以制备无需后修饰的叠氮功能化聚氨酯预聚物。这种预聚物可以通过点击化学轻易形成稳定的多孔弹性体进行交联，而无需使用有毒的多异氰酸酯。通过简单地调整预聚物浓度或叠氮/炔烃的交联比，就可以调节力学性能。因此，多孔弹性体的杨氏模量在 0.52 至 2.02 MPa 之间变化。当制备具有致密结构的叠氮功能化聚氨酯弹性体时，杨氏模量在 0-15%应变下增加到 28.8 MPa。断裂伸长率达到 150%，与市售的尼龙-12 相当。多孔和致密弹性体在 20%应变下分别可以进行至少 200 和 1000 次的弹性变形而不失效。该材料在碱性溶液中的抗侵蚀能力相当稳定。体内生物相容性研究表明，在小鼠皮下植入 2 个月以上没有降解。植入物只引起轻微的炎症反应和纤维囊。这种材料可能有助于制造生物医学设备的弹性部件。
