Structure conducting polymers

All these data show that only small changes of the polymerization parameters may lead to characteristic differences in the resulting structures of conducting polymers. Structural properties - for example, regularity and homogeneity of chain structures, but also chain length play an important role in our understanding of the properties of such materials. Spectroscopic methods have proved particularly... 

The differently produced conductive polymer structures described above all have enhanced conductivity, which can be employed in microelectronics [44] and as sensors using immobilized enzymes [46, 47[. Martin and coworkers used polarized infrared absorption spectroscopy to access the alignment of the polymer fibers on the outer surface of the nanotubes [48[. The study showed that the enhancement of the conductivity is due to the alignment of the polymer fibers on the outer surface of the tubes. 

Typical Conducting Polymer Structures (in Undoped Form)... 

R. Yang, D.F. Evans, L. Christensen and A. Hendrickson, Scanning tunneling microscopy evidence of semicrystalline and helical conducting polymer structure, J. Phys. Chem., 1990, 94, 6117. 

A conductive polymer structure can be used as a host structure for various metal or metallic oxide particles. The advantage of this concept is the possibility of obtaining highly dispersed catalysts, with a very low amount of metal. This is particularly interesting when noble metals are used. 

Della Santa A, Mazzoldi A, de Rossi D (1996) Steerable microcatheters actuated by embedded conducting polymer structures. J Intell Mater Sys Stmct 7 292... 

Figure 10.17 AFM image of a PPY nanowire created by guided growth. (Reprinted with permission from Journal of the American Chemical Society, Guided Growth of Nanoscale Conducting Polymer Structures on Surface-Functionalized Nanopatterns by M. Woodson etal., 128, 11. Copyright (2006) American Chemical Society)...

M. Woodson and J. Liu, Guided growth of nanoscale conducting polymer structures on surface-functionalized nanopattems, J. Am. Chem. Soc., 128, 3760-3763 (2006). 

CLASS Polyheterocyclics conjugated conducting polymers STRUCTURE Polythiophene exists in two structures (Aromatic)... 

Table 1 Typical conducting polymer structures (undoped form)...

The membrane is the heart of the MEA. The principal roles of the membrane are both to separate the anode and cathode compartments, and to ensure ionic conductivity. It consists of a proton-conducting polymer structure with functional fixed groups, generally carboxylic -COj or sulfonate -SO3, and mobile protons when the membrane is humidified. 

Conductive polymer nanostructures synthesized using porous silieon (PSi) templates are described, with an emphasis on PSi template advantages, pore-filling phenomenon, meehanism of polymerization, and selective removal of PSi to release the polymerie struetures. The interaction of pyrrole monomers, as a case study, on the entire surfaee of PSi under both galvanostatic and potentiostatie deposition modes is presented with discussion on the processing issues assoeiated with the electrochemical deposition process inside the pores. Additionally, various materials infiltrated into PSi templates are briefly deseribed. Examples of fi ee-standmg conductive polymer structures formed by selective dissolution of PSi are provided. 

The number of new conducting polymer structures that are reported in the open literature continues to grow at nearly 500 articles per month. This incredible amount of research devoted to the study of EAPs attests to their imique scientific properties and their potential widespread use in commercial applications. In order to fully exploit their potential applications one must begin with their synthesis and properties. 

Della Santa, A. Mazzoldi, A. De Rossi, D. Steerable microcatheter actuated by embedded conducting polymer structures. J. InteU. Mater. Sys. Structures, vol. 7, n3 (1996), pp. 292-300... 

There are essentially three ways in which polymers can be made electrically conducting via their own structures. These are via pyrolysis, doping and by producing an inherently conductive polymer structure such as via the incorporation of a transition metal atom into the polymer backbone. This chapter is principally devoted to conductive polymers of these types, but there is also another method of introducing conductivity to a polymer. In this method conductivity is achieved via the incorporation of conductive fillers. Although in this case the conductivity is not related to the chemistry of the polymer, but rather to the nature of the filler, these materials have been widely exploited commercially, and are thus worthy of inclusion in this chapter. 

Doping by various guest species, as noted previously, induces a full-scale co-operative structural reorganization within the host matrix. Since these side-chain-containing conducting polymer structures are initially more complex than those of the linearly unsubstituted materials, the overall structural response and location of the dopant ions is even more difficult to assess. Nevertheless, recent scattering studies have found an enormous range of detailed physical behavior. 

The two previous sections focused exclusively on the most general structural properties that occur as a natural consequence of conducting polymer synthesis and the subsequent treatments of bulk samples. In fact, there are a variety of even more evolved conducting polymer structures that may be generated though highly specialized processing and/or synthesis procedures. This section briefly discusses only one of the many possible novel structural architectures that have been envisioned. 

In this chapter I have briefly touched upon many, but certainly not all, of the historical developments and current issues concerning conducting polymer structure and the associated structural phase behavior. Clearly the level of knowledge is most advanced for conducting polymer hosts that have extensive crystallinity and high symmetry structures. Unfortunately, very few model host systems fulfill this criterion. Still, in the less ordered materials, the most general features of the microscopic structure are reasonably well understood. 

Finally, the most exciting new opportunity afforded by research in this area is that under appropriate conditions superconductivity may be induced in conductive polymer structures. Since high-Tc superconductor systems can be used as the source of the superconductivity, it may be possible to drive conductive polymer systems into the superconducting state at temperatures well above 100 K. The search for superconductivity in organic polymeric systems has been an important goal in the field of conductive polymers and has attracted the attention of scientists for more than three decades [12]. 

S. G. Haupt and J. T. McDevitt, Possible induction of superconductivity in conductive polymer structures, Synth. Met. 77 1539 (1995). 

Having created conducting polymer structures and developed appropriate lines of communication. We can assemble systems whereby tlie material s properties can be controlled in-situ. Then performance on demand is possible. Tlie degree of control available and how this can be utilised is best illustrated by considering some areas of application currently being developed in our laboratories. 

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