Structure changes of electrorheological fluids based on polyaniline particles with various hydrophilicities and time dependence of shear stress and conductivity during flow

0357479 - ÚMCH 2011 RIV CZ eng J - Journal Article
Stěnička, M. - Pavlínek, V. - Sáha, P. - Blinova, Natalia V. - Stejskal, Jaroslav - Quadrat, Otakar
Structure changes of electrorheological fluids based on polyaniline particles with various hydrophilicities and time dependence of shear stress and conductivity during flow.
Colloid and Polymer Science. Roč. 289, č. 4 (2011), s. 409-414. ISSN 0340-1960
R&D Projects: GA ČR GA202/09/1626; GA AV ČR IAA400500905
Institutional research plan: CEZ:AV0Z40500505
Keywords : hydrophilicity * hydrophobicity * electrorheology
Subject RIV: CD - Macromolecular Chemistry

Particles of polyaniline protonated with perfluorooctanesulfonic acid provided a material with hydrophobic surface. This property enabled its perfect dispersion in silicone oil due to its good compatibility with the hydrophobic medium. In contrast, in a suspension of hydrophilic polyaniline particles doped with sulfamic acid, strong interactions of particles prevailed, which led to the formation of entangled chains of aggregated particles in suspension. The difference in structural properties of suspensions exists already in the absence of electric field and significantly influences their electrorheological behavior after application of electric field. The formation of electrorheological structure has been monitored by recording time dependences of the shear stress and the electric current passing through the flowing suspensions.
Permanent Link: http://hdl.handle.net/11104/0195748