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P. Dorfinger, R. Liska, J. Stampfl:
"Toughening of Photopolymers for SLA";
Talk: 20. Symposium Verbundwerkstoffe und Werkstoffverbunde 2015, Wien; 07-01-2015 - 07-03-2015; in: "20th Symposium on Composites", Materials Science Forum, Volumes 825-826 (2015), ISBN: 978-3-03835-515-1; 53 - 59.

Lithography-based additive manufacturing technology (L-AMT) is a layered manufacturing approach where liquid photopolymerizable resins, which contain a photoinitiator, are solidified with ultraviolet or visible light. The advantage of the L-AMT (e.g. stereolithography) versus other AMT is the excellent precision and the high achievable resolution. With the SL systems used for this work, resolutions of 25 microns are achievable. The disadvantages of this technology are the insufficient mechanical properties of the final parts. Only thermosets such as (meth)acrylates and epoxies are printable, which are characterized by a high degree of cross-linking. These thermosets are quite brittle and not very suitable in most applications. In this work, high-molecular-weight acrylate-based resins are investigated regarding their mechanical properties (toughness, strength and Young`s modulus). The goal is to mimic the thermo-mechanical properties of engineering polymers like ABS and polypropylene. The main components of the resin are mono- and difunctional acrylate oligomers, leading to a polymer network with relatively low crosslinking density. To further improve the toughness of the resulting polymers, the influence of added core-shell-particles (CSP) is investigated. At room temperature the impact strength and the heat deflection temperature in comparison to other SLA-materials is improved. The tensile modulus is more than 3,000 MPa and hence about 1,000 MPa higher than comparable materials

3d-printing, photopolymers, impact strength

http://dx.doi.org/10.4028/www.scientific.net/MSF.825-826.53