Abstract Biodegradable stents (BRS) offer the potential to improve long-term patency rates by providing support just long enough for the artery to heal. However, manufacture BRS is rather difficult. Nowadays 3D additive manufacturing could be an interesting manufacturing method to produce BRS. In this context, this work presents a novel 3D Additive Manufacturing Machine to be used to manufacture BRSs based on polymers and discusses the effect the process parameters have on the physical features of the BRS. The printing nozzle temperature, flow rate, speed, and trajectories effects on polycaprolactone stents were studied. Printed samples were analysed using Optical Microscopy, Differential Scanning Calorimetry (DSC), and the Radial Expansion Test to study the effects printing parameters have on their dimensional precision, material structure distribution, and radial behaviour, respectively. Results showed that the dimensional precision of a BRS is strongly influenced by printing temperature and flow rate, although printing speed did not exert any influence. Printing parameters did not significantly influence the structure of the materials. Furthermore, the samples, with an average expansion ratio of 320% and around 22% of recoil ratio, showed good radial behaviour.

中文翻译：

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3D 打印生物可吸收聚己内酯支架：工艺参数对其物理特性的影响

摘要 可生物降解支架 (BRS) 通过提供刚好足以让动脉愈合的支撑来提高长期通畅率。然而，制造BRS是相当困难的。如今，3D 增材制造可能是生产 BRS 的一种有趣的制造方法。在这种情况下，这项工作提出了一种新型 3D 增材制造机器，用于制造基于聚合物的 BRS，并讨论了工艺参数对 BRS 物理特性的影响。研究了打印喷嘴温度、流速、速度和轨迹对聚己内酯支架的影响。使用光学显微镜、差示扫描量热法 (DSC) 和径向膨胀测试对印刷样品进行分析，以研究印刷参数对其尺寸精度的影响，分别为材料结构分布和径向行为。结果表明，BRS 的尺寸精度受印刷温度和流速的影响很大，尽管印刷速度没有任何影响。印刷参数对材料的结构没有显着影响。此外，平均膨胀率为 320% 和反冲率为 22% 左右的样品显示出良好的径向性能。