Rheological Characterization of BaTiO3 Sol-Gel Transition

BaTiO3 gels were prepared by hydrolysis and polycondensation reactions between titanium isopropoxide and barium hydroxide in presence of methoxyethanol, methanol and water. The rheology of the sol-gel transition was studied with a rheometer allowing low amplitude sinusoidal oscillations. Experimenta...

Full description

Saved in:
Bibliographic Details
Published inJournal of sol-gel science and technology Vol. 9; no. 1; pp. 5 - 15
Main Authors Brasseur, A, Michaux, B, Pirard, R, O Van Cantfort, Pirard, J P, Lecloux, AJ
Format Journal Article
LanguageEnglish
Published New York Springer Nature B.V 01.01.1997
Subjects
Barium hydroxide
Barium titanates
Dilution
Gelation
Gels
Growth models
Moisture content
Polycondensation reactions
Rheological properties
Rheology
Sol-gel processes
Viscoelasticity
Online AccessGet full text

Cover

More Information
Summary:BaTiO3 gels were prepared by hydrolysis and polycondensation reactions between titanium isopropoxide and barium hydroxide in presence of methoxyethanol, methanol and water. The rheology of the sol-gel transition was studied with a rheometer allowing low amplitude sinusoidal oscillations. Experimental data show a continuous increase in the complex viscosity along with time, showing the progressive character of the transition. The influence of synthesis operating variables was studied. The gelation time, which definition is based on viscoelastic measurements, increases exponentially when the water content is increased, when the dilution due to the methoxyethanol is reduced or when the temperature is lowered. Different growth models were used for the characterization of the particles in the solution. These models suggest that the polymerisation first produces spherical particles (mass fractals) and that these spherical particles then agglomerate to form a linear network.
ISSN:0928-0707
1573-4846
DOI:10.1023/A:1026496104827