Conductive blends of polyaniline

J. D. Sudha, S. Sivakala, R. Prasanth, V. L. Reena, and P. Radhakrishnan Nair, Development of electromagnetic shielding materials from the conductive blends of polyaniline and polyaniline-clay nanocomposite-EVA Preparation and properties. Compos. Sci. Technol., 69, 358-364 (2009). 

Yoon, C.O., M. Reghu, D. Moses, A.J. Heeger, and Y. Cao. 1994. Electrical-transport in conductive blends of polyaniline in poly(methyl methacrylate). Synth Met 63 (l) 47-52. 

Conductivity and Thermopower of Blends of Polyaniline with Insulating Polymers... 

CONDUCTIVITY AND THERMOPOWER OF BLENDS OF POLYANILINE WITH INSULATING POLYMERS (PETG AND PMMA)t... 

Yang, C.Y., Y. Cao, P. Smith, and A.J. Heeger. 1993. Morphology of conductive, solution-processed blends of polyaniline and poly(methyl methacrylate). Synth Met 53 (3) 293-301. 

The formation of electrically conductive fibers of polyaniline blended with poly(p-phenylene terephthalamide) processed from sulfuric acid was also reported by Hsu et al. [72]. A thoroughly mixed solution of 0.2 wt% emeraldine base and 17.6 wt% poly(p-phenylene terephthalamide) was dissolved in sulfuric acid and this dope solution was extruded at 80°C through a 20-hole spinneret into a 1°C water coagulation bath. The continuous 20 filament yarns that were collected on the bobbin were thoroughly washed with water, which probably led to partial deprotonation of the emeraldine salt. However, the... 

Zhang, Q.H., Wang, X.H., Chen, D.J., and (ing, X.B. (2004) Electrically conductive, melt-processed ternary blends of polyaniline/dodecylbenzene sulfonic acid, ethylene/vinyl acetate, and low-density polyethylene./. Pdym. Sci. B, 42, 3750-3758. 

Sudha, J.D., Sivakala, S., Patel, K., and Nair, P,R, (2010) Development of electromagnetic shielding materials from the conductive blends of polystyrene polyaniline-clay nanocomposite. Compos. Part A, 41,1647-1652. 

Heeger s research group obtained monofilament conductive fibers from a blend of polyaniline and poly(/ -phenyleneterephthalamide) (Kevlar from DuPont) [88]. The monofilament fibers, with different concentrations of polyaniline, were wet-spun from a solution of the component polymers in sulfuric acid, into a 1 N sulfuric acid solution. In the process, a draw ratio of 7 20 and an extrusion speed of 0.12-0.3mmin enabled the continuous production of bobbins. These were sprayed with deionized water to prevent fiber collapse and to remove the excess of sulfuric acid. The bobbins were immersed in HCl to protonate the polyaniline and dried in a vacuum oven. Pure polyaniline fibers were also wet spun by the same method. The Kevlar fibers become brittle with an increase in the concentration of polyaniline. In general, the mechanical properties of the fibers change proportionally to the concentration of polyaniline. Enhancement of the strain at break occurs at the expense of electrical conductivity. The most significant result from this work was the observation that small amounts of polyamide improved markedly the mechanical properties of polyaniline fibers, while retaining its conductivity (10 S cm ). 

A latex can be used to form conductive blends of thermoplastic rubber with TT-conjugated polymers such as polyaniline, polypyrrole, and poly(3-methoxythiophene) made from Fe(ni), Fe(ii), Cu(ii)-H202 in-situ aqueous oxidation systems. The composite films were then obtained by hot pressing. Suitable polymerization conditions involved using HCl, aniline... 

C. -J. Liu, and B. Wessling, Conductivity and thermopower of blends of polyaniline with insulating polymers (PETG and PMMA), Sol. State Commun., 97(57 235 (19%). 

Stockton, W.B. Rubner, M.F., "Electrically Conducting Compatible Blends of Polyaniline/Poly (Vinyl Pyrrolidone)", p. 257 in Garito, A.F. Jen, A.K-Y. Lee, C. Y-C. Dalton, L.R. (Eds.), Mat. Res. Soc. Symp. Proc., Vol. 328 Electrical, Optical, and Magnetic Properties of Organic Solid State Materials, Materials Research Society, Pittsburgh, Pennsylvania, USA... 

Nand et al. (2012) observed an increase in spin concentrations in polyaniline/ PE blends as the polyaniline composition of the blends increased [23]. However, there was a slight discrepancy between the observed and theoretical spin concentrations of the blends, and this was attributed to redox transitions of polyaniline during the melt processing. Moreover, the peak to peak resonance line width (AH p) decreased as the fraction of polyaniline increased, indicating good dispersion and formation of a partially conducting network of polyaniline in the PE matrix [23]. 

Polyblend fiber composites of polyaniline, doped with dodecylbenzene-sulfonic acid, and PE exhibited a conductivity of 2 S cm with 40 wt % polyaniline composition, but the percolation threshold was 10%. Hoiser et al. (2001) also obtained polyaniline/ PE blends with conductivities in the range lO " to lO " S cm and a percolation threshold of 10% [45]. Blends of polyaniline doped with camphor sulfonic acid and ultra high molecular weight PE displayed a percolation threshold of 5% with the conductivity being about 10 S cm [47]. The conductivity of extruded polyaniline/ PE blends increased from 3.38 x 10" to 1.19 x lO " S cm as the polyaniline varied from 5 to 20 wt % [23]. No percolation threshold was observed up to 20 wt % loading as the polyaniline used to prepare the blends was not doped by any added acids, as had been the case in other studies. 

Norris et al. produced fine fibers with desired conductivity by using Polyaniline/PEO polymeric blends (Norris et al. 2000). The fiber diameters were in the range of 950 nm to 2.1 pm. Wilkes observed the dependence of fiber diameter distribution and the occurrence of beaded structures on the flow rate and applied electric potential (Wilkis 2007). Fibers from 148 nm to 5 pm were obtained by Wilkes. 

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