The BioPolyMed project, funded by the German Federal Ministry of Education and Research, aimed to develop biodegradable polymers with mechanical and antimicrobial properties suitable for medical devices such as catheters, packaging films, and connectors. The study focused on a range of polyesters and copolymers, including PLLA‑ε‑caprolactone, Resomer L 210 S, Resomer LC 703 S, and Biomer P 304, and compared them to a reference PVC material.

Technical Results
Thermal analysis by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) revealed that Resomer LC 703 S has a glass‑transition temperature (Tg) of 21 °C (DMTA) and a melting point of 112 °C (DSC). Its storage modulus at 25 °C is 1060 MPa, close to the 2090 MPa of the reference polypropylene film (PP 1013 H1). Resomer L 210 S shows a Tg of 80 °C and a modulus of 3160 MPa, comparable to the 2130 MPa of the reference polycarbonate connector (PC 2858). Biomer P 304 exhibits a high modulus of 1030 MPa and a Tg of 17 °C, while the reference PVC (PVC RB3NDG) has a low modulus of 5.5 MPa and a Tg of –27 °C.
Mechanical testing of tensile specimens indicated that Resomer LC 703 S reaches an ultimate tensile strength of 45 MPa, whereas Resomer L 210 S and Biomer P 304 achieve strengths above 1000 MPa. All biodegradable polymers, except the PVC reference, are degradable in aqueous conditions at 50 °C, completing significant mass loss within 30 days.
Plasticization with acetyltributyl citrate (ATBC) reduced the Tg of Resomer LC 703 S to 33–41 °C, depending on the 5–10 % loading, while maintaining a storage modulus of 70–30 MPa at 25–37 °C. This adjustment brought the material’s flexibility within the range required for a lung catheter. The addition of 0.2 % polyhexamethylene biguanide (PHMB) or 0.01–0.1 % copper colloid conferred antimicrobial activity, as confirmed by zone‑of‑inhibition tests against common pathogens.
Electron‑beam sterilization at 25 kGy did not degrade the polymer chains, preserving mechanical integrity. 3D‑printed connectors fabricated from Resomer L 210 S filaments (1.75 mm diameter) exhibited dimensional accuracy within ±0.1 mm and retained a modulus of 3100 MPa, suitable for medical connector applications.
Demonstrator components were produced: a 16 mm inner‑diameter catheter tube from Resomer LC 703 S/ATBC, a biodegradable film from Resomer LC 703 S, and a connector from Resomer L 210 S. All components were coated with an antimicrobial layer and passed preliminary biocompatibility tests.

Collaboration
The project was executed by a consortium of academic and industrial partners. The Institute for Nonlinear Mechanics (INM) led the polymer synthesis and characterization, while RoweMed supplied additive‑manufacturing expertise for 3D‑printed connectors. The University Hospital Greifswald (University of Greifswald) provided clinical testing facilities for catheter prototypes. Funding and project coordination were managed by the BioPolyMed program under the BMBF. This multidisciplinary collaboration enabled rapid translation from material development to functional medical device demonstrators.