Tallow rosin based binder for extrusion 3D printing feedstock loaded with reactive metal powders

Nowadays, due to the growing use of 3D printing technologies with metal nanoparticles, the use of feedstock components that are toxic to humans, non-renewable and non-degradable in nature is a serious concern. The aim of this study is to develop a new feedstock binder based on a natural non-toxic material—tallow rosin as the main polymer for 3D printing green parts with reactive Ti/Al powder. The binder formulation comprising ethylene-vinylacetate copolymer EVA—rosin -dioctyladipate for producing feedstocks loaded with reactive metal powders with a wet chemical method to avoid powder contact with air oxygen has been proposed. From the green parts with thickness of 7 mm by the method of solution debinding with the use of isopropyl alcohol at ambient temperature is removed in 24 h up to 87% and in 48 h 100% of rosin and dioctyladipate. The efficiency of solution debinding has been found to be increase with increasing dispersity and powder loading. The amount of residual carbon in the sintered parts does not depend on the residual polymer content and does not exceed 0.2 wt%.