Additive manufacturing or 3D printing as an umbrella term for various materials processing methods has distinct advantages over many other processing methods, including the ability to generate highly complex shapes and designs. However, the performance of any produced part not only depends on the material used and its shape, but is also critically dependent on its surface properties. Important features, such as wetting or fouling, critically depend mainly on the immediate surface energy. To gain control over the surface chemistry post-processing modifications are generally necessary, since it′s not a feature of additive manufacturing. Here, we report on the use of initiator and catalyst-free photografting and photopolymerization for the hydrophilic modification of microfiber scaffolds obtained from hydrophobic medical-grade poly(ε-caprolactone) via melt-electrowriting. Contact angle measurements and Raman spectroscopy confirms the formation of a more hydrophilic coating of poly(2-hydroxyethyl methacrylate). Apart from surface modification, we also observe bulk polymerization, which is expected for this method, and currently limits the controllability of this procedure.

中文翻译：

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用于 3D 打印医用级聚（ε-己内酯）的无引发剂和无催化剂水凝胶涂层工艺

增材制造或 3D 打印作为各种材料加工方法的总称，与许多其他加工方法相比具有明显的优势，包括生成高度复杂的形状和设计的能力。然而，任何生产部件的性能不仅取决于所使用的材料及其形状，而且还严重依赖于其表面特性。润湿或结垢等重要特征主要取决于直接表面能。为了控制表面化学后处理修改通常是必要的，因为它不是增材制造的特征。这里，我们报告了使用引发剂和无催化剂的光接枝和光聚合对从疏水性医用级聚（ε-己内酯）通过熔融电写获得的超细纤维支架进行亲水改性。接触角测量和拉曼光谱证实了更亲水的聚（2-羟乙基甲基丙烯酸酯）涂层的形成。除了表面改性，我们还观察到本体聚合，这是该方法所预期的，目前限制了该过程的可控性。