Conjugated polymers structures

Namely, if the double bond was saturated ( ) simultaneously when it formed, the retardation of the development of conjugated polymer structure might be expected. We chose the reduction with diimide (NH=NH) for the saturation of double bond. Thus, p-toluenesulfonyl hydrazide (PSH) was used which acts as a diimide source under the condition (130-150°C) of PVC-processing. 

Since the publication of the original observation in 1977 there has been an explosive growth of research into the whole range of conjugated polymer structures which has led to the development of a new family of polymers which, with appropriate chemical modification, can display conductivities from poor semiconductor to comparable with copper. These polymers have obviously been the result of major contributions from synthetic chemists and have been of great interest to solid-state physicists. Somewhat surprisingly there has been less interest on the part of polymer scientists. This has led to problems in many areas, partly because of failure to recognise the... 

Figure 20.3 Examples of conjugated polymer structures accessible using ADMET.

It is possible to form a chiral conjugated polymer structure by utilizing a liquid crystalline (asymmetric) environment. It is therefore unnecessary to introduce a chiral substituent to the monomer or employ the use... 

Alternatives to LB techniques for the preparation of multilayer thin films are also available. Control of the microscopic ordering can be achieved through structured self-assembly methods. Lamellar conjugated polymer structures have been prepared [105] using in situ electrochemical polymerization of heteroarene-contain-ing surfactants from micellar solutions. This method avoids the highly controlled conditions necessary for monolayer film formation. 

The rigid chemical structure of a conjugated polymer helps in the movement of electrons. That stiff structure, however, has limited its use. They are like uncooked spaghetti and do not easily entangle themselves. Polymer chain entanglements are necessary to achieve high viscosities, which are required to create fibers out of these polymers. 

Structures of different conjugated polymers including various thiophenes (3,4,8,9,10,11) and pyrroles 12,5,6,7) that show color variation. (From A. A. Argun. R Aubert, B. Thompson, I. Schwendeman, C. L. Gaupp, J. Hwang. N. J. Pinto. D. B. Tanner, A. G. MacDiarmid, J. R. Reynolds "Multielectrochromism in Polymers Structures and Devices" Chem. Mater. 2004, 1B, 4401-4412). 

The science and technology of conducting polymers are inherently interdisciplinary they fall at the intersection of three established disciplines chemistry, physics and engineering hence the name for this volume. These macromolccular materials are synthesized by the methods of organic chemistry. Their electronic structure and electronic properties fall within the domain of condensed matter physics. Efficient processing of conjugated polymer materials into useful forms and the fabrication of electronic and opto-electronic devices require input from engineering i. e. materials science (more specifically, polymer science) and device physics. 

The versatility of poly(phenylcne) chemistry can also be seen in that it constitutes a platform for the design of other conjugated polymers with aromatic building blocks. Thus, one can proceed from 1,4- to 1,3-, and 1,2-phenylene compounds, and the benzene block can also be replaced by other aromatic cores such as naphthalene or anthracene, helerocyclcs such as thiophene or pyridine as well as by their substituted or bridged derivatives. Conceptually, poly(pheny ene)s can also be regarded as the parent structure of a series of related polymers which arc obtained not by linking the phenylene units directly, but by incorporation of other conjugated, e.g. olefinic or acetylenic, moieties. 

Electronic Structure of Surfaces and Interfaces in Conjugated Polymers... 

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