A team of professors from the School of Materials Science and Technology of Donghua University has made important progress in the field of 3D printing thermosetting materials. They combine salt particles and thermosetting material prepolymers into 3D-printable "composite ink", which can realize a variety of thermosetting materials (such as cross-linked polymerization). Ester, polyurethane, epoxy resin) direct extrusion 3D printing.
3D printing technology can quickly and efficiently manufacture fine and complex three-dimensional structures, and has shown good application prospects in many fields. Thermosetting materials have excellent mechanical properties, thermal stability and chemical resistance. However, the molding of most thermosetting materials (especially non-photocurable materials) requires a long cross-linking process, which is difficult to match the continuous manufacturing method of 3D printing.
 In this regard, the team proposed a novel strategy to combine salt particles and thermosetting material prepolymers into a 3D printable "composite ink". The salt particles act as a thickener during the 3D printing process to ensure smoothness Print molding; in the thermal curing process, the salt granules also act as a reinforcing agent to achieve the three-dimensional printed structure to maintain shape during the high temperature and high vacuum crosslinking process; in the printing process, after the salt granules are cured and molded, they can be conveniently The water is dissolved and removed, thereby obtaining a porous structure as a porogen. The inspiration for adding salt comes from the concrete materials commonly used in civil engineering. Cement mixed with a certain proportion of stones, sand and other filler materials can strengthen the support structure and improve the compressive strength. The team said that the strategy has good versatility and can achieve direct extrusion 3D printing of a variety of thermosetting materials. The printed structure also has micropores that are difficult to obtain with conventional 3D printing.