Materials Science Forum, Vol.480, 549-555, 2005
Rheology and heat treatment of zirconia based gels synthesized from sodium glycozirconate precursor
Zirconia based gels were prepared by the sol-gel route using sodium tris(glycozirconate) complex as precursor synthesized directly from the reaction of inexpensive and readily available compounds via the one step method. Rheological technique was used to investigate the sol-gel transition of zirconium based materials at different water/alkoxide ratios and reaction temperatures. The gelation time was determined from the evolution of the storage and loss moduli versus time at various frequencies using the Winter-Chambon criterion. The effect of an increase of the hydrolysis ratio and/or temperature was an enhancement of the kinetics of crosslink reactions, thus decreasing the gelation time. The variation of the gelation time versus temperature could be described by Arrhenius law. Furthermore, zirconia powders prepared from the thermal treatment at 500 degrees C were analyzed by X-ray diffraction and the BET technique.