Polypyrrole Nanocomposites

There are several reports of Ag nanocomposites with conducting polymers like polyaniline [38] and polypyrrole [39]. However, electrical conducting properties of green metal - starch... 

Joshi PP, Merchant SA, Wang YD, Schmidtke DW (2005). MEMS sensor material based on polypyrrole-carbon nanotube nanocomposite film deposition and characterization. J. Micromech. Microengin. 5 2019-2027. 

Apart from the insulating polymeric matrices, conductive polymers such as polypyrrole and polyaniline have been used as nanocomposite electrodes by chemical or electrochemical polymerization [13, 17, 116, 117]. Such materials provide high conductivity and stability. However, the use of insulating polymers can be more advantageous than the conductive polymers when employed in cyclic voltammetry. 

Intercalation of electroactive polymers such as polyaniline and polypyrrole in mica-type layered silicates leads to metal-insulator nanocomposites. The conductivity of these nanocomposites in the form of films is highly anisotropic, with the in-plane conductivity 10 to 10 times higher than the conductivity in the direction perpendicular to the film. Conductive polymer/oxide bronze nanocomposites have been prepared by intercalating polythiophene in V2O5 layered phase, which is analogous to clays. °° Studies of these composites are expected not only to provide a fundamental understanding of the conduction mechanism in the polymers, but also to lead to diverse electrical and optical properties. 

Anxiliary agents support materials such as PMMA chemical oxidant determines the size of particles in polypyrrole/silica nanocomposites ... 

An, K.H., Jeon, K.K., Heo, J.K., et al. (2002). High-capacitance supercapacitor using a nanocomposite electrode of single-waUed carbon nanotube and polypyrrole. J. Electrochem. Soc., 149, A1058-62. 

In addition to the above-mentioned conventional polymers, several interesting developments have taken place in the preparation of nanocomposites of MMT with some specialty polymers including the N-heterocyclic polymers like poly (N-vinylcarbazole) (PNVC) [32, 33], polypyrrole (PPY) [34, 35], and polyaromatics such as polyaniline (PANI) [36-38]. PNVC is well known for its high thermal stability [39] and characteristic optoelectronic properties [40-43]. PPY and PANI are known to display electric conductivity [44-46]. Naturally, composites based on these polymers should be expected to lead to novel materials [47,48]. 

Since the late 1980s several innovative syntheses of polypyrroles have been discovered. The photosensitized polymerization of pyrrole in aqueous solution and in polymer matrices using tris(2,2 -bipyridine)ruthenium(II) as a photosensitizer has been reported <89CC132>, and PPy can be photochemically deposited on to any type of surface under visible light irradiation conditions <89CC657, 90CC387). The preparation and potential applications of surface-functionalized polypyrrole-silica nanocomposite particles have been discussed <94PP217>. 

Antibacterial Importance of a Biodegradable Polypyrrole/ Dextrin Conductive Nanocomposite... 

The polypyrrole (Ppy)/dextrin nanocomposite is synthesised via in situ polymerisation and the preparation of this nanocomposite is shown in Figure 5.4. The backbone chain of this nanocomposite polymer contains hydrophobic side chains, which disrupt the microbial cell membrane leading to leakage of the cytoplasm in bacteria including Escherichia coli. Pseudomonas aeruginosa. Staphylococcus aureus and Bacillus subtilis. This material can be implemented in the fields of biomedicine, biosensors and food packaging due to the biodegradable property of dextrin as well as the antibacterial properties of the Ppy [79]. 

Natural biodegradable polymers with tailor-made properties offer excellent opportunities for advanced functional materials, e.g., biodegradable conductive nanocomposites based on polypyrrole (Ppy)/dextrin or PANI/dextrin provide enhanced conductive and antibacterial activities. 

V. Georgakilas, P. Dallas, D. Niarchos, N. Boukos, and C. Trapalis, Polypyrrole/MWNT nanocomposites s3mthesized through interfacial polymerization, Synth. Met, 159, 632-636 (2009). 

S.T. Selvan, T. Hayakawa, M. Nogami, and M. Moller, Block copolymer mediated synthesis of gold quantum dots and novel gold-polypyrrole nanocomposites, J. Phys. Chem. B, 103, 7441-7448 (1999). 

Y.C. Liu, H. Lee, and S.J. Yang, Strategy for the synthesis of isolated fine silver nanoparticles and polypyrrole/silver nanocomposites on gold substrates, Electrochim. Acta, 51, 3441-3445 (2006). 

E. Pinter, R. Patakfalvi, T. Fiilei, Z. Gingl, I. Dekany, and C. Visy, Characterization of polypyrrole-silver nanocomposites prepared in the presence of different dopants, J. Phys. Chem. B, 109, 17474-17478 (2005). 

T. Zhang, R. Yuan, Y. Chai, W. Li, and S. Ling, A novel nonenz3fmatic hydrogen peroxide sensor based on a polypyrrole nanowire-copper nanocomposite modified gold electrode, Sensors, 8, 5141-5152 (2008). 

S. Letai ef, P. Aranda, and E. Ruiz-Hitzky, Influence of iron in the fomiation of conductive polypyrrole-clay nanocomposites, Appl. Clay ScL, 28, 183-198 (2005). 

K. Boukerma, J-Y. Piquemal, M.M. Chehimi, M. Mravcakova, M. Omastova, and P. Beaunier, Synthesis and interfacial properties of montmorillonite/polypyrrole nanocomposites, Polymer, 47, 569-576 (2006). 

Polypyrrole nanocomposites with iron oxide and other nanoparticles have been prepared by several methods. For example, in situ chemical oxidative polymerization approach with either ultrasonication [59] or mechanical stirring [60] was reported. The nanocomposites showed particle-loading-dependent magnetic properties and electric conductivity. In addition, a supercritical fluid approach, implemented because of green chemistry, was also reported to be used as a medium in in situ chemical oxidative polymerization for the fabrication of conductive-polymer magnetic nanocomposites [61]. 

A microemulsion polymerization method [62,63] was also reported to produce magnetic polypyrrole nanocomposites filled with 7-Fc203. The nanoparticles were dispersed in the oil phase. FeCla was used as an oxidizing agent. Sodium dodecylbenzenesulfonic acid (SDBA) and butanol were used as the surfactant and cosurfactant, respectively. FeCl3 (0.97 g) was dissolved in a mixture of 15 mol deionized water, SDBA (6 g), and butanol (1.6 ml). A specific amount of 7-Fc203 suspended nanoparticle solution was added to the above solution for dispersion. Pyrrole was added for nanocomposite polymer fabrication in the microemulsion system. The polymerization was continued for 24 hours and quenched by acetone. 

Figure 12.2 (Reprinted with permission from Journal of Nanoparticle Research, Fabrication and Characterization of Iron Oxide Nanoparticles Reinforced Polypyrrole Nanocomposites, by Z. Guo, K. Shin, A. B. Karki et al., 11 (6) 1441-1452. Copyright (2009) Springer Science + Business Media")...

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