Nihon Reoroji Gakkaishi
Online ISSN : 2186-4586
Print ISSN : 0387-1533
ISSN-L : 0387-1533
Electrorheological Response of Silicone Oil Suspension of Barium Strontium Titanate Particles with Different Surface Compositions
Yoshio KobayashiRyusuke MorimotoKoji MoriyamaTomoaki SatohMikio Konno
Author information

2005 Volume 33 Issue 5 Pages 285-287


Electrorheological response of barium strontium titanate (BST)/silicone oil suspension was experimentally studied with measurements of generated shear stress in a range of field frequency (200-4000 Hz) under steady shear. The BST particles were synthesized by the hydrolysis of complex alkoxide precursor that was prepared in a reflux of metallic barium, metallic and tetraethylorthotitanate in solvent. The hydrolysis was performed by the addition of water/ethanol solution to the precursor solution. Generated shear stress of as-prepared (unannealed) BST particles system decreased with an increase in frequency, while that for 1100 °C-annealed BST system increased with frequency. XPS measurements revealed that alkoxyl groups that were derived from unreacted alkoxide were on surface of the as-prepared BST particles, and the annealing at 1100 °C decomposed the alkoxyl groups to hydroxyl groups. Difference in electric conductivities of the surfaces is considered to be responsible for the different shear stress behaviors of the as-prepared and annealed particles.

Information related to the author
© 2005 The Society of Rheology, Japan
Previous article