Nanostructured conductive composite

FIGURE 14.5 (See color insert.) Corrosion rate of MO-PANI/COPU and CSA-PNA/LOPU composite coatings in (a) 5% HCl, (b) 5% NaOH, and (c) 3.5% NaCl. (Reprinted from Prog. Org. Coat., 65, Riaz, U. et al. Effect of Dopant on the Corrosion Protective Performance of Environmentally Benign Nanostructured Conducting Composite Coatings, 405, Copyright 2009, with permission from Elsevier.)... 

Riaz, U., Ahmad, S.A., Ashraf, S.M., and Ahmad, S. (2009) Effect of dopant on the corrosion protective performance of environmentally benign nanostructured conducting composite coatings. Prog. 

A simple method was recently introduced for preparing core-shell nanostructured conductive PPy composite [45]. The PPy core particles were first introduced in flexible shell solutions by in situ polymerization, and then different core-shell structures could be obtained by the electrospinning method (Figure 4.12). In that study, PPy was selected as the as-dispersed phase (cores) and polyacrylonitrile (PAN) as the continuous phase (shell) the morphology of the resulted nanostructures can be controlled by changing the concentration of the solutions. This method is very useful in the design and preparation of nanosized core-shell structures using electroconductive polymers. 

Figure 4.12 Schematic illustration of the mechanism for preparing core-shell nanostructured conductive PPy composites. (Reprinted with permission from Materials Letters, Fabrication of Polyacrylonitrile/polypyrrole (PAN/Ppy) composite nanofibers and nanospheres with core shell structures by electrospinning by X. Li, X. Hao, H. Yu and H. Na, 62, 1155-1158.

Table 14.1 gives an alphabetical listing of electrochemical sensors based on nanostructured conducting-polymer materials and composites. The main sensor characteristics have been extracted from the literature. The data given in the table are based on values extracted from the associated publications, either directly, or approximated from graphical data. The comments principally refer to abbreviations of the synthetic and deposition methods used, as well as other pertinent characteristics of the sensor. Responses or sensitivity values are based on either single data or slopes determined from calibrations. Detection limits are either formal limits of detection, or the lowest concentrations determined in the work, and... 

Being in the nanotechnology era, novel nanostructured composite materials are expected to be designed showing improved properties due to nanostructuration. Moreover, composite electrodes from expensive metals (gold, platinum, etc.) can be prepared using the NPs as conductive fillers, with enhanced properties but at lower prices compared to their pure conductor counterparts. 

Rryszewski, M., and J.K. Jeszka. 1998. Nanostructured conducting polymer composites—Super-paramagnetic particles in conducting polymers. Synth Met 94 (1) 99-104. 

S. M. Ashraf, S. Ahmad and U. Riaz, Development of novel conducting composites of linseed-oil based poly(urethane amide) with nanostructured poly(l-naphthylamine) , Polym Int, 2007,56,1173-81. 

Nanostructured Thermoset Composites Containing Conductive Ti02 Nanoparticles... 

Kryszewski, M. and Jeska, J. K. 1998. Nanostructured conducting polymer composites—superparamagnetic particles in conducting polymers. Synthet. Metal. 94 99-104. 

Nano-composites (NCs) are materials that comprise a dispersion of particles of at least one of their dimentions is 100 nm or less in a matrix. The matrix may be single or multicomponent. It may include additional materials that add other functionalities to the system such as reinforcement, conductivity and toughness (Alexandre and Dubois, 2000). Depending on the matrix, NCs may be metallic (MNC), ceramic (CNC) or polymeric (PNC) materials. Since many important chemical and physical interactions are governed by surface properties, a nanostructured material could have substantially different properties from large dimensional material of the same composition (Hussain et ah, 2007). 

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