微波水热2.doc

Original Contribution Synthesis and electrorheology of rod-like titanium oxide particles prepared via microwave-assisted molten-salt method M.?Sedlacik1, 2??,?M.?Mrlik1, 3,?Z.?Kozakova1, 3,?V.?Pavlinek1, 3?and?I.?Kuritka1, 3 (1) Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01?Zlin, Czech Republic (2) Department of Production Engineering, Faculty of Technology, Tomas Bata University in Zlin, T. G. Masaryk Sq. 275, 762 72?Zlin, Czech Republic (3) Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, namesti T. G. Masaryka 275, 762 72?Zlin, Czech Republic ? ? M.?Sedlacik Email:?msedlacik@ft.utb.cz Received:?11?June?2012Revised:?24?September?2012Accepted:?10?October?2012Published online:?23?October?2012 Abstract The rod-like titanium dioxide (TiO2) particles were synthesized by a simple and rapid microwave-assisted molten-salt method. The X-ray diffraction analysis revealed the phase composition transformation from the anatase phase of original TiO2?nanomaterial to the rutile phase of high crystallinity. Scanning electron microscopy proved the conversion of originally globular particles of original anatase TiO2?sized from 200 to 500?nm into rods with a length of 5–10?μm and a diameter between 0.5 and 2?μm. The electrorheological (ER) measurements performed under steady-state flow as a function of the applied electric field strength and particle concentration showed that suspended rutile rod-like TiO2?particle-based fluid exhibits much higher ER activity than that of original anatase TiO2?material powder. These observations were clearly demonstrated by viewing their dielectric spectra analyses. Keywords ?Electrorheology?Titanium oxide?Rod-like particles?Rutile?Anatase?Microwave-assisted molten-salt method?Dielectric properties Introduction Electrorheological (ER) fluids are two phase systems consisting of polarizable semiconducting particles homogeneously dispersed within an insulating carrier liqu