DSC and FT-IR analysis of the drying process of titanium alkoxide derived precipitates

The drying process of titanium alkoxide-derived precipitates has been studi ed by means of FT-IR spectroscopy and DSC analysis. From the FT-IR spectrum , it has been possible to observe that unhydrolyzed alkoxide molecules cont inue the hydrolysis process by using water molecules retained inside the st ructure of the precipitate or formed by condensation of the K-OH groups. Ho wever, the quantification of the water content inside the precipitate was c arried out by DSC analysis. This technique also allowed to determine two ki nds of water molecules: free or interstitial water and coordinatively bound water. These two kinds of water gave two endothermic peaks at ca. 160-180 degrees and 305 degrees C, respectively. The transformation of the amorphou s precipitate to a crystalline one is detected by an exothermic peak at ca. 314 degrees C. The elimination of the coordinatively bound water is associ ated with this crystalline transformation. (C) 1999 Published by Elsevier S cience B.V, All rights reserved.