NOVEL ELECTRORHEOLOGICAL FLUIDS WITH POLYMER PARTICLES CONTAINING ORGANIC DOPANTS

Green electrospinning is a relatively new promising technology in which a polymer (latex) can be spun from an aqueous dispersion with the help of a template polymer. This method is a green, clean and safe technology that is able to spin hydrophobic polymers using water as an electrospinning medium. In this article, a systematic study that investigates the influence of the template polymer molar mass, the total solids content of the initial dispersion and the particle/template ratio is presented. Furthermore, the influence of the surfactant used to stabilize the polymer particles, the surface functionality of the polymer particles and the use of a bimodal particle size distribution on the final fiber morphology is studied for the first time. In green electrospinning, the viscosity of the initial complex blend depends on the amount and molar mass of the template polymer but also on the total solids content of the dispersion to be spun. Thus, both parameters must be carefully taken into account in order to fine-tune the final fiber morphology. Additionally, the particle packing and the surface chemistry of the polymer particles also play an important role in the obtained nanofibers quality.

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Coating of Polyaniline with an Insulating Polymer to Improve the Power Efficiency of Electrorheological Fluids

International Journal of Modern Physics B ◽

10.1142/s0217979299001983 ◽

1999 ◽

Vol 13 (14n16) ◽

pp. 1931-1939 ◽

Cited By ~ 9

Author(s):

J. Akhavan ◽

K. Slack ◽

V. Wise ◽

H. Block

Keyword(s):

Power Efficiency ◽

Electrorheological Fluids ◽

Emeraldine Base ◽

Heavy Duty ◽

Base Form ◽

Static Yield ◽

High Fields ◽

Er Fluids ◽

Er Fluid ◽

A Current

Currents drawn under high fields often present practical limitations to electrorheological (ER) fluids usefulness. For heavy-duty applications where large torques have to be transmitted, the power consumption of a ER fluid can be considerable, and for such uses a current density of ~100μ A cm -2 is often taken as a practical upper limit. This investigation was conducted into designing a fluid which has little extraneous conductance and therefore would demand less current. Selected semi-conducting polymers provide effective substrates for ER fluids. Such polymers are soft insoluble powdery materials with densities similar to dispersing agents used in ER formulations. Polyaniline is a semi-conducting polymer and can be used as an effective ER substrate in its emeraldine base form. In order to provide an effective ER fluid which requires less current polyaniline was coated with an insulating polymer. The conditions for coating was established for lauryl and methyl methacrylate. Results from static yield measurements indicate that ER fluids containing coated polyaniline required less current than uncoated polyaniline i.e. 0.5μ A cm -2. The generic type of coating was also found to be important.

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