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.

中文翻译：

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叠氮基官能化聚氨酯，可通过单击化学制备可调节的弹性体

聚氨酯是一种重要的生物材料，在生物医学工程中具有广泛的应用。在这里，我们报告了一种无需后改性即可制备叠氮基官能化聚氨酯预聚物的新方法。这种预聚物可以通过点击化学轻松地形成稳定的多孔弹性体，以进行交联，而不是使用有毒的多异氰酸酯。可以通过简单地调节用于交联的预聚物浓度或叠氮基/炔烃比来调节机械性能。因此，对于多孔弹性体，杨氏模量在0.52至2.02MPa之间变化。当叠氮基官能化聚氨酯弹性体的结构紧凑时，在0-15％应变下，杨氏模量增加到28.8 MPa。断裂应变达到150％，可与市售的Nylon-12相媲美。多孔弹性体和致密弹性体在20％的应变范围内都可以分别经历至少200和1000个循环的可逆弹性变形，而不会失效。该材料在碱性溶液中显示出相当强的抗腐蚀稳定性。体内生物相容性研究表明，在2个月的时间内，皮下植入小鼠并没有降解。植入物仅引起轻度的炎症反应和纤维化囊。这种材料可能对制造生物医学设备的弹性体组件有用。植入物仅引起轻度的炎症反应和纤维化囊。这种材料可能对制造生物医学设备的弹性体组件有用。植入物仅引起轻度的炎症反应和纤维化囊。这种材料可能对制造生物医学设备的弹性体组件有用。