Electrical property effect polyaniline

Hydrogen bond formation as a result of the interaetion of polymer with solvent was found to contribute to changes in the electric properties of polyaniline.Hydrogen bonding causes changes in conformal structure of polymer chains. This increases the electrical conductivity of polyaniline. Water is especially effective in causing such changes but other hy-... 

An extensive review of the synthesis of rc-conjugated polymers is presented using a tutorial approach to provide an introduction to the field intended for the undergraduate student and the experienced chemist alike. The many synthetic methodologies that have been used for the synthesis of conjugated polymers are outlined for each class of polymers with a focus on research from the 1990s. The effect of structure on electrical properties is detailed. Specific systems reviewed include the polyacetylenes, polyanilines, polypyrroles, polythiophenes, poly(arylene vinylenes), and polyphenylenes. 

Metal-Polyaniline Nanocomposites Based on Polyaniline Nanofibers Electrical Properties of Metal-Polyaniline Nanocomposite Materials Other Methods to Make Metal-Polyaniline Nanocomposites Growth of Inorganic Nanoparticles by In Situ Metathesis Reactions Unusual Photothermal Effect of the Polyaniline Nanofibers Flash Welding.7-30... 

Kieffel, Y, J.P. Travers, A. Ermolieff, and D. Rouchon. 2002. Thermal aging of undoped polyaniline Effect of chemical degradation on electrical properties. J Appl Polym Sci 86 (2) 395—404. 

A. Soroudi, M. Skrifvars, H. Liu, Polyaniline-polypropylene melt-spun fibre filaments the collaborative effects of blending conditions and fibre draw ratios on the electrical properties of fibre filaments, J. Appl. Polym. Sci. 119 (2011) 558—564. 

Parameters such as, synthesis medium (HCl, camphor sulfonic add (CSA) or dodecylbenzene sulfonic acid (DBSA)), molar ratio aniline/oxidant, method for oxidant addition, temperature, polymerization duration, dedoping conditions will have effects on polymer properties in terms of yield, chain length, effective conjugation, defects rate, and electrical properties. Temperature was kept to 0 C, -30 C or -40 C and reactions were stopped after various durations in order to control the molecular weight of samples. Polymerization durations were varied from 1 hour to 5 days and depended on the reaction temperature. The inherent viscosities of the polyanilines (Pani) were determined at 25 °C in 0.1%w solutions in concentrated sulfuric acid (95 %), using an Ubbelohde viscometer. For instance, high viscosity samples (1.4 dl/g) were obtained after 3 days at -40 °C vsMe low viscosity samples (0.6 dl/g) were obtained after 1 hour at 0 A relationship was found between polymerization duration and inherent viscosity for polymers synthesized at low temperature (- 40 °C). Inherent viscosity increases from 0.6 to 1.4 when duration of polymerization increases from one to five days. In the case of synthesis at 0°C no correlation was obtained between duration of polymerization and inherent viscosity. A careful control of other parameters (synthesis medium, molar ratio aniline/oxidant, method for oxidant addition) have permitted to get samples with inlierent viscosities ranging from 0.55 to 2.1 dl/g in a reproducible way. 

Other phenolic compounds have also been shown to cause similar changes in conformation and physical properties of PAn.HCSA salts. Most of these, like m-cresol 1, are highly corrosive and toxic, limiting their desirability for processing and enhancing the electrical conductivity of polyanilines. However, we have recently found that the structurally related molecules thymol 2 and carvacrol 3, which are much less toxic than m-cresol, can also function as effective secondary dopants for PAn.( )-HCSA films and increase the electrical conductivity by up to two orders of magnitude. ... 

The physical properties of ICPs can also be manipulated by incorporating polyelectrolytes (PEs) as dopants. For example, sulfated polyO-hydroxy ethers) have been incorporated with dramatic effects on the mechanical properties -increasing the stretchability to greater than 200% [147,148]. Others [149] have shown that polyanilines can be rendered water soluble by incorporation of appropriate polyelectrolytes such as polystyrenesulfonate. Electrically conducting gels (materials with high water content/good conductivity) are also formed by incorporation of polyelectrolytes as dopants [150,151]. 

Both Buchwald and Hartwig have explored the use of palladium-catalyzed amination for the synthesis of dendrimers and polyanilines. Dendrimers, such as 48, can be easily assembled through sequential aiylation of aminoanilines.89 These dendrimers are useful in creating metal-organic frameworks and often can exhibit interesting electronic effects, such as diradicals, and as optical materials. Polymeric anilines 49 are of intense interest due to their unique electrical conducting properties. Using the... 

F. Yakuphanoglu, R. Mehrotra, A. Gupta, and M. Munoz, Nanofiber organic semiconductors The effects of nanosize on the electrical charge transport and optical properties of bulk polyanilines, J. Appl. Polym. Sci, 114, 794-799 (2009). 

Dufour, B., P. Rannou, P. Fedorko, D. Djurado, J.P Travers, and A. Pron. 2001. Effect of plasticizing dopants on spectroscopic properties, supramolecular structure, and electrical transport in metallic polyaniline. Chem Mat 13 4032. 

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