Influência da adição de defloculante, ligante e partículas de alumina no comportamento reológico de suspensões a base de frita e caulim

Abstract

Recebido em 2/12/96; aceito em 10/9/97 INFLUENCE OF ADDED DEFFLOCULANT, BINDER AND ALUMINA PARTICLES ON THE RHEOLOGICAL BEHAVIOR OF ENAMEL SUSPENSIONS. Enamel suspensions were characterized according to their rheological behavior. The suspensions presented a pseudoplastic behavior, yield stress and thixotropy, with or without the presence of deffloculant. Added carboxymethylcel-lulose increases the apparent viscosity of enamel suspensions and interacts complexly with the deffloculant, here sodium silicate. Addition of crystalline particles of two types of alumina, used to improve the wear resistance of ceramic glazes, also change strongly the rheological behavior of the suspensions. Added high specific area, irregular alumina particles produce a higher increase of the apparent viscosity of enamel suspensions compared to rounded ones.