Additive Manufacturing with Thermoplastic Collagen

Thermoplastic collagen is a partially denatured collagen powder which can be processed by thermoplastic methods such as extrusion and injection molding, but was hitherto not adapted for the use in additive manufacturing (AM) techniques. This paper describes the first successful application of collagen/water/glycerol mixtures in an AM process using a BioScaffolder 3.2 from GeSiM mbH. Strands of molten collagen were deposited onto a building platform forming differently shaped objects. The collagen melt was characterized rheologically and optimal processing conditions were established. The technique includes the use of supporting structures of PLA/wood composite for samples with complex geometry as well as post-processing steps such as the removal of the supporting structure and manual surface smoothing. The manufactured objects are characterized concerning water solubility, swelling behavior and compressibility. Possible applications are in the non-medical sector and include collagen-based pet food or customized organ models for medical training.