Green Monomers for 3D Printing: Epoxy-Methacrylate Interpenetrating Polymer Networks as a Versatile Alternative for Toughness Enhancement in Additive Manufacturing
Antonella Fantoni, J. Ecker, Mojtaba Ahmadi, Thomas Koch, Jürgen Stampfl, Robert Liska, Stefan Baudis
Abstract
High Resolution Image Download MS PowerPoint Slide Photopolymerization represents an environmentally friendly polymerization technique due to the ability of solvent-free and room-temperature curing. However, industrially used resins are usually derived from fossil resources, inherently increasing the environmental impact of such materials. Herein, the preparation of sequential interpenetrating polymer networks (IPNs) with a high content of renewable carbon by means of free radical photopolymerization and thermal epoxy curing was investigated in detail. Therefore, poly(ethylene glycol) dimethacrylate was used as UV-curable monomers, and resorcinol diglycidyl ether and trimethylolpropane were polymerized via step-growth polyaddition. Before the fabrication of IPNs, the networks were evaluated separately regarding their reactivity by means of (photo)-differential scanning calorimetry and real-time near-infrared photorheology. A combination of both networks resulted in IPNs with superior (thermo)mechanical properties and the ability to 3D-print complex shapes via stereolithography.