Conducting polymer solutions

FIGURE 1.23 Communicating with a conducting polymer PPy/Cl in solution (a) cyclic voltammetry—a plot of current flow versus the electrical (potential) stimulus applied (b) the electrochemical quartz crystal mircobalance readout—mass polymer versus electrical (potential) stimulus applied (c) the resistometry readout—resistance of the polymer versus the electrical (potential) stimulus applied. (Printed with permission from Materials Science Forum, Vol. 189-190, Characterization of conducting polymer-solution interfacial processes using a new electrochemical method, A. Talaie, G. G. Wallace, 1995, p. 188, Trans Tech Publications, Switzerland.)... 

An interesting result obtained recently shows that the substrate employed may dictate the surface (polymer/solution) properties of even relatively thick polymers.39 For example, with polymers grown from dodecyl sulfate (DS)-containing electrolytes, the nature of the substrate used dictated the hydrophobicity/hydrophilicity of the conducting polymer-solution interface. Polymers grown on a carbon-foil substrate shown to be hydrophobic produced a more hydrophilic polymer surface. Finally, those grown on platinum, a more hydrophilic substrate, produce a more hydrophobic polymer. 

A Novel Phase of Organic Conductors Conducting Polymer Solutions... 

Interestingly, when the potential is made more positive so that the film becomes oxidized, the observed force-distance data remain the same. Similar effects were observed with polypyrrole films. This suggests that the positive charge in the film is fully compensated by negatively charged solution ions that can penetrate the polymer matrix either within the polymer strands or within pores in the polymer, as depicted in Fig. 11. Thus, at the conductive polymer-solution interface, no DL exists. This is in stark contrast to the behavior of metal electrodes in contact with aqueous electrolytes. 

Nylon 6,6 is often blended with PPO (Noryl GTX) to make extremely rigid polymers for exterior body panels. Most of its applications are in Europe, in automobile fenders. This product is offered by General Electric Plastics, which currently is developing a commercial conductive polymer solution to facilitate production-line painting. Absorption of moisture by nylon remains a continuing critical issue to be dealt with to meet the performance requirements. 

Organic Conductors Conducting Polymer Solutions in Polymers in Electronics , T. Davidson, ed., American Chemical Society, Washington, D.C., 1984, pps. 447-59 cf also "Conductive Polymers, pps. 423-584. 

Membrane keypads face significant competition from new technologies now being developed. For example, research at the University of Pennsylvania and Yamanashi University, by Hohnholz, Okuzaki and MacDiarmid [5], involves the fabrication of a polymer-dispersed fiquid crystal display using electrodes of poly(3,4-ethylenedioxythiophene) doped with poly(4-styrene sulfonate) in conjunction with a push-button keyboard array. The display is produced by the design and printing of a line pattern on a substrate which is then coated with a conductive polymer solution. Subsequently the reverse-printed toner pattern is removed. 

Inhibition of the Ion Exchange Processes at Conducting Polymer Solution Interface... 

Scenario Ic. Backflow test is conducted, polymer solution properties are fixed. Increase Pilot Test probability of success. 

Electrochemical methods are applicable in our case due to the inherent conductivity of the polymers under investigation. As will be shown throughout this work, electrochemical methods provide the major means of communicating with conducting polymer-solution interfaces. Given our current fascination with electronic communications, it is fortuitous that conducting polymers are so open to communication through this medium. 

---