In this study, polythiophene (PT) and polythiophene/ borax conducting composite (PT/borax) were in‐situ synthesized using FeCl3 as oxidizing agent containing 89.2% PT and 10.8% borax. The electrorheological (ER), creep‐recovery, and vibration damping characteristics of the PT/borax composite were investigated. A volume fraction series (φ = 5–25%) of the PT/borax/silicone oil dispersions were prepared and sedimentation stabilities were determined. An ER activity was observed from the samples, when subjected to external electric field strength thus, they were classified as smart materials. Some parameters affecting the ER properties of the dispersions such as volume fraction, shear rate, electric field strength, frequency and temperature were investigated. Creep tests were applied to the suspensions to investigate the viscoelastic behaviors and recoverable viscoelastic deformations observed. Finally, real time vibration damping experiment was carried out on a modified automobile shock absorber and a 68% vibration damping capacity determined for borax/SO suspension system under E = 0.3kV/mm condition. POLYM. COMPOS., 2011.© 2011 Society of Plastics Engineers

In this study, synthesis of polythiophene (PT) and polythiophene/borax pentahydrate (PT/borax) conducting composite were carried out by in‐situ oxidative polymerization. The composite was subjected to various characterization techniques namely: FTIR, particle size, magnetic susceptibility, density, conductivity, dielectric, TGA, XRD, SEM, and zeta (ζ)‐potential measurements. The effects of time, pH, various surfactants, electrolytes and temperature on the ζ‐potential of PT and PT/borax composite were investigated. In a basic medium the ζ‐potential of the composite was observed to decrease up to ζ = −66.5 mV. The most effective surfactant on the ζ‐potential of the composite was sodium dodecyl sulfate, which reduced the value of ζ‐potential to ζ = −39.2 mV. It was concluded that the presence of mono‐valent (NaCl) salt has no impact on ζ‐potential whereas, di‐valent (BaCl2) salt shifted the ζ‐potential value to more positive regions. Elevated temperatures caused almost no change on the ζ‐potential of the composite. Also an electrorheological effect (a tremendous viscosity increase) was determined from the PT/borax colloidal systems under an externally applied electric field, and the results obtained will be discussed in the forthcoming article. POLYM. COMPOS., 2011. © 2010 Society of Plastics Engineers

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In this study, poly(vinyl chloride) (PVC), polyindole (PIN), and PVC/PIN conducting composites having five different compositions were used. Particle sizes, densities, dielectric constants, and sedimentation ratios of the materials were determined. The zeta‐potentials of the samples were measured in aqueous and nonaqueous (silicone oil [SO]) media. The dispersions prepared in SO were subjected to external electric field strength, and their electrorheological properties were investigated. Then the effects of dispersed particle volume fraction, shear rate, external electric field strength, frequency, and temperature onto electrorheological activities of the dispersions were examined. Further, creep and creep‐recovery tests were applied to the PIN/SO and PVC/PIN/SO dispersions, and reversible viscoelastic deformations were observed. Finally, the vibration damping capacity of PVC (66%)/PIN (34%)/SO dispersion system was tested by using an automobile shock absorber. Copyright © 2011 John Wiley & Sons, Ltd.

This study aims to develop poly(vinyl chloride) (PVC) composites prepared by melt mixing by using a combination of talc and calcined kaolin as filler in order to improve the disadvantages of rigid PVC, which is widely used in industry, such as poor mechanical properties and low thermal stability. In addition, PVC/talc and PVC/calcined kaolin composites were also examined for comparison. The calcined kaolin is modified with urea to increase the surface area (chemical treatment), while the surface of both fillers is coated with stearic acid for good compatibility with PVC (mechanical treatment). Scanning electron microscopy micrographs showed homogeneous distribution of mechanically processed fillers. Attenuated total reflectance-Fourier-transform infrared spectroscopy analysis revealed successful coating of the fillers with stearic acid. Also, new bands were detected in the spectrum of urea-treated calcined kaolin, showing an effective chemical treatment. It has been observed that the treatment of fillers improves the mechanical properties of PVC. Thermogravimetric results showed that delaminated calcined kaolin increased the thermal stability of PVC composites. The results of this study proved that binary filler composites combine good properties of both (synergistic effect) and good filler dispersion can be obtained by using stearic acid and urea.