Material Extrusion 4D Printing of Epoxy Vitrimers

다국어 초록 (Multilingual Abstract)

Additive manufacturing field have emerged as a rapid and customizable process to both industrial and individual user. Polymers are the most generally used materials because of the processability and high mechanical properties. Here we demonstrate an epoxy vitrimers base 4D printing via engineered associative covalent adaptable networks (CANs). Vitrimers were synthesized using functional groups of epoxy and carboxylic acid, where the rapid dynamic bond exchange were possible by tuning the amount of catalyst. Ratio between epoxies and carboxylic acids are modulated to adjust the suitable properties for 3D printing. With optimized conditions, 3D printed vitrimers demonstrate shape memory and welding performance owing to its cross linkages and rapid dynamic bond exchange, respectively. Rheometer, dynamic mechanical analysis, and wide angle X-ray scattering experiments are conducted to investigate the physical properties and chain dynamics.