Development of Multifunctional Resins for 3D Microprinting Applications

Abstract

In the field of tissue regeneration, polymers are widely used for the manufacturing of scaffolds. Instructive structures, based on crosslinked polymers are expected to provide a proper environment for proliferation, migration and differentiation of the embedded cells/tissue. In order to mimic the natural extracellular matrix (ECM), the scale of the scaffolding needs to be in the micron range. Unlike conventional printing techniques, two photon polymerization (2PP) is capable of creating micro- (and even nano-) sized three-dimensional features with high resolution. In general, commercially available resins for 2PP lack the ability to be chemically post modified. Also, mechanical properties are difficult to tune. Especially, post-modification reactions might be very useful in the coupling of growth factors onto the scaffolds, which can lead to an even higher control over cell behavior. In this master thesis, the synthesis of photocurable resins for two photon polymerization was investigated. Besides crosslinker molecules and a photoinitiator, polymers were added to the mixture. These polymers were synthesized via an iniferter mechanism in a flow-setup. This variant of RAFT polymerization provide high end-group fidelity of the polymers. Resins, which include such polymers, were crosslinked in the 2PP process yielding microstructures with the end-groups onto the surface. These end groups can be modified to control cell behavior.