The subject of this diploma thesis is the 3D printing of commonly available polymers and the modification of their surfaces using low‑temperature plasma, intending to develop materials suitable for biomedical models on which decontamination procedures can be studied. The polymers investigated in this work include polypropylene (PP), acrylonitrile butadiene styrene (ABS), and thermoplastic polyurethane (TPU), which were fabricated by the FDM method in both planar and three‑dimensional forms.
Within this thesis, the surfaces of the polymers were modified using dielectric barrier discharge (DBD) plasma and a microwave argon plasma jet. Changes in surface properties were analyzed by measuring the contact angles of water, ethylene glycol, and diiodomethane, followed by the calculation of surface free energy components. The time stability of plasma‑induced surface modifications under laboratory conditions was also investigated, and the influence of surface morphology resulting from the 3D printing process and selected printing parameters was evaluated.
The results demonstrated that plasma treatment led to a significant decrease in the water contact angle for all studied polymers and to an increase in surface polarity, indicating enhanced wettability and potentially improved biocompatibility. The most pronounced effect on smooth surfaces was observed for ABS, whereas when surface texturing was taken into account, the strongest effect was detected for TPU samples. Good short‑term stability of the surface modifications was confirmed for PP and ABS, although slight surface aging was observed for ABS within the studied time frame. The effectiveness of plasma treatment for more complex 3D structures was strongly influenced by sample geometry and the type of plasma source used.
The thesis also investigated the effect of the presence of polymer plates, both untreated and plasma‑treated, on the growth of Staphylococcus epidermidis in liquid culture. During a two‑week cultivation period, no significant differences in bacterial growth were observed compared to control samples, indicating the biological inertness of the studied polymers with respect to the planktonic growth of S. epidermidis.
The obtained results confirm that low‑temperature plasma is an effective tool for the targeted modification of surface properties of 3D‑printed polymers without either negative or positive effects on bacterial growth, and that these materials can serve as suitable model systems for studying plasma decontamination procedures.