Rheology and Printability of Pastes Based on BaTiO3 Nanopowder Depending on Ethyl Cellulose Viscosity

Abstract

This paper is about rheology of pastes based on BaTiO3 nanopowder with ethyl cellulose 100 cP (paste P1) and 10 cP (paste P2) as organic binder. It was established, that P1 was pseudoplastic – thixotropic system and P2 was rheopexic - pseudoplastic – thixotropic one. The reduction of EC viscosity led to changing of paste structurization type from pseudoplastic (P1) to plastic one (P2). Structurization of P1 can be explained with excess of polymer in the paste composition and with dominance of the polymer – polymer bonds. Unlike P1, P2 has some elastic properties due to strong structural links because of polymer – nanoparticle bonds. Moreover, the value of initial viscosity of P2 (2.11 Pa∙s) was much less than of P1 (37,5 Pa∙s). It was found, that the viscosity of polymer influences the paste printability. In particular, P2 was more prone to form thinner and smoother prints. Thus, composition of P2 was more promising one for obtaining prints with good quality and subsequent assembly into a multilayer object due to its elastic properties during low deformation.