Material investigations on poly(ethylene glycol) diacrylate-based hydrogels for additive manufacturing considering different molecular weights

The aim of this case study is to generate several poly(ethylene glycol) diacrylate-based hydrogels using additive manufacturing processes. The interest here is in determining different material properties. The test specimens are produced using a commercial stereolithography system. For this purpose, three formulations are prepared. The basis in each case is PEGDA with average molecular weights of 700 Mn, 575 Mn and 250 Mn. A photoinitiator and a UV absorber are added to ensure spatial and temporal cross-linking. Furthermore, the formulations are tested for their material properties according to ISO standards using tensile, compression and hardness tests. An equivalence can be found in the tensile and compression tests. The results with the molecular weights of 700 Mn and 575 Mn show values close to each other. However, the results of the material tests with the molecular weight of 250 Mn are ten times higher. The Shore A hardness values also correlate with the previous tests. These results between molecular weight and material property are particularly striking. A novel aspect of this method could be that the properties determined of these tailor-made high-performance polymers can be applied to different areas of application in an organism.