New Monomers for Tough Photopolymers [thesis]

Johannes Steindl, Christian Gorsche, Robert Liska
2021
Photopolymers are a widely spread class of materials. They are utilised in thin layer applications such as inks and protective and decorative coatings to more sophisticated uses like medical applications or additive manufacturing technologies. Nevertheless, lack of toughness still limits utilisation of bulk materials in industry. For this purpose, several promising concepts were already published in literature to overcome these drawbacks (e.g. toughening additives or modification of the polymer
more » ... tion of the polymer network). However, they exhibit other disadvantages such as high viscosity, decrease of other (thermo)mechanical properties in exchange for toughness or are quite simply too expensive for many areas.Therefore, the aim of this thesis was to investigate new approaches to tackle brittleness in photopolymers. Thus, two different independent plans were pursued and studied in detail ranging from resin characterisation to determination of (thermo)mechanical properties of the final materials.On the one hand, new cross-linking monomers were synthesised containing blocked isocyanates, which could be cleaved thermally. So, a change in network architecture from highly cross-linked to linear thermoplastic polymers was achieved.On the other hand, a concept was developed, which was modelled on ABS as a very prominent and tough engineering plastic. Unfortunately, ABS cannot be photopolymerised. Thus, new terpolymers based on maleimide, styrene and polybutadiene were explored to mimic structure and properties of ABS. Furthermore, additional derivatives were synthesised to optimise monomer and material characteristics and to acquire a deeper understanding of these novel transparent ABS-like photopolymers. Finally, three different potential applications were shown (reactive diluent for commercial highly viscous resins, frontal polymerisation and 3D printing), which could pave the way for this new promising photopolymer class in research and industry.
doi:10.34726/hss.2021.38979 fatcat:t6mb5qo45nfvfagnbde4j4u2di