An initiator- and catalyst-free hydrogel coating process for 3D printed medical-grade poly(ε-caprolactone)

Beilstein J Org Chem. 2021 Aug 19:17:2095-2101. doi: 10.3762/bjoc.17.136. eCollection 2021.

Abstract

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.

Keywords: additive manufacturing; light-induced polymerization; self-initiated photografting and photopolymerization; surface modification; surface-initiated polymerization.

Grants and funding

We gratefully acknowledge financial support by the Volkswagen Stiftung (Grant# 93 417).