Structure and growth kinetics of zirconium hydrous polymers in organic solutions

The objective of this study was to understand the kinetics of hydrolysis an d condensation reactions and structures of zirconium hydrous polymers forme d by these reactions. Small angle X-ray scattering (SAXS) measurements were made on solutions for an aging period ranging from 109 ms to few days. Res ults prove that condensation reactions start before completion of hydrolysi s and as a result polymers formed at the earlier stages (t approximate to 1 00 ms) are weakly crosslinked (linear), On further aging, due to the intern al condensation process these weakly cross-linked polymers convert to highl y branched polymers with a structure identical to an ideal Gaussian randoml y branched polymer with a persistent length (building block) of 8.3 +/- 0.5 Angstrom. (C) 1999 Published by Elsevier Science B.V. All rights reserved.