Thermogravimetric analysis of organic binder segregation during drying of particulate suspensions

Thermogravimetric analysis (TGA) was used to evaluate microstructural evolution and binder segregation during drying of particulate suspensions of submicrometer alumina. The addition of 2 and 4 wt.% poly(vinyl alcohol) (PVA) binder decreased the evaporation rate by ~12 and ~20%, respectively, during the constant rate drying period. Increasing the PVA molecular weight (MW) extended the drying time also. At 4 wt.% addition, an acrylic emulsion binder did not affect the drying behavior but at 2 wt.% addition, the initial evaporation rate decreased by approximately 24%. It is shown that the TGA can be used to determine the drying stages of a particulate suspension during drying. (C) 2000 Elsevier Science B.V.