Synthesis, characterization and electrorheological properties of poly(o‐toluidine)/Zn conducting composites

Abstract

In this study, the synthesis, characterization, and electrorheological (ER) properties of poly(o-toluidine)/ Zn, (POT/Zn), composites were investigated. Syntheses of the composites were carried out by a chemical method using ammonium persulfate, (NH 4 ) 2 S 2 O 8 , (APS), as a free radical initiator. The composites were characterized by Fourier transform infrared (FTIR) spectroscopy, electrical conductivity, magnetic susceptibility, particle size measurements, and scanning electron microscopy (SEM). A series of Zn-containing composites were prepared (0.8-7.6% by mass), and their conductivities were measured to be within the range of 1.7 Â 10. Magnetic properties of POT/Zn composites were analyzed by Gouy scale measurements; it was found that their conducting mechanisms are bipolaron. A series of particle size (13, 17, 18, 26, 83 mm) were prepared by ground milling the crude POT/ Zn composites. Colloidal suspensions of POT/Zn composites were prepared in silicone oil (SO), at a series of concentrations (10-30%, m/m), and sedimentation stabilities were measured at 258C. ER measurements showed that the POT/Zn/SO suspension system was ER active. Thus, the effects of solid particle concentration, shear rate, electric field strength, addition of polar promoters, and temperature (25-1258C) onto ER activities of suspensions were investigated. The ER activity of suspensions was increased with increasing particle concentration and electric field strength and decreasing shear rate and showing a nonNewtonian flow behavior. t ¼ 1.1 kPa shear stress was reached for POT/Zn (4.1 wt %, Zn) composite under E ¼ 2.0 kV, c ¼ 15 (%, m/m), _ g ¼ 1:0 s À1 , and T ¼ 258C conditions. It was found that the ER activity was slightly decreased with increasing temperature. Further, the addition of polar promoters had no promoting effect on the ER activity of the suspensions and POT/Zn/ SO system was classified as dry ER materials.

Electrorheology of polymers and nanocomposites

“…[44][45][46] Since the first report on PANI-clay nanocomposite-based ER fluids 47,48 from an emulsion polymerization method as shown in Fig. 3, polymers (e.g., PANI, PPy, and styrene-acrylonitrile copolymer) and clay nanocomposites have been extensively used as suspended particles, 49,50 taking advantage of either hydrophobic or hydrophilic surface characteristics of clay.…”

Monodisperse poly(2-methylaniline) coated polystyrene core–shell microspheres fabricated by controlled releasing process and their electrorheological stimuli-response under electric fields

“…In this paper, a new core-shell structured ER particle system comprised of a PANI derivative [28,29] of poly(2-methylaniline)-coated polystyrene (PS/PMAN) microspheres prepared using a controlled swelling-releasing process based on pre-fabricated PS seeds in dispersion polymerization. Compared to PANI, the PMAN has a lower conductivity by several orders of magnitude.…”

Synthesis, electrorheology and creep behavior of polyindole/polyethylene composites

“…Conducting polymers have been used widely in many areas such as rechargeable batteries, diodes, transistors, sensors and electrorheological (ER) studies [1][2][3][4][5][6]. Among these classes of polymers, polyaniline (PAn), polypyrrole (PPy) and polythiophene (PT) have been studied extensively because of their good conductivity and relative stability.…”