Polyaniline manufacture

The polyaniline was prepared by emulsion polymerization following the procedure outlined in US patent 5,863,465 with DNNSAused as a dopant [22]. Carbon Nanotubes (CNI) manufactured the nanotubes used in the work either by a high-pressure fabrication method (Hipco SWNT) or via laser ablation (Laser SWNT). We found that excellent dispersions of the nanotubes in PANI could be produced by two different procedures. The nanotubes could either be directly sonicated into the PANI solution or first sonicated into xylene and that dispersion afterwards sonicated into the DNNSA-PANI solution. 

Practical applications have been reported for PVP/cellulosics (108,119,120) and PVP/polysulfones (121,122) in membrane separation technology, eg, in the manufacture of dialysis membranes. Electrically conductive polymers of polyaniline are rendered more soluble and hence easier to process by complexation with PVP (123). Addition of small amounts of PVP to nylon 66 and 610 causes significant morphological changes, resulting in fewer but more regular spherulites (124). 

Nowadays, aniline remains one of the basic starting materials, not only in the dye industry but also in the chemical industry (for polyaniline, polyurethane) and pharmaceutical industry (for the manufacture of drugs such as antipyrine, antifebrin etc.)33. World demand for aniline is expected to grow at an impressive rate of several percents per year... 

Oligoanilines and polyanilines (PANIs) have been extensively investigated for nearly 180 years due to their simple cost-effective chemical/electro-chemical synthesis, unique physico-chemical properties, excellent environmental stability, and numerous potential applications ranging from the first reported use in dyeing and printing manufacture/industry under common commercial name aniline black, discovered and developed in... 

Fibers containing intrinsically conductive polymer are manufactured from a composition containing an organic acid salt of an intrinsically conductive polymer, a matrix polymer, and a spinning solvent. Polyaniline is the intrinsically conductive polymer. Polyaniline alone cannot be processed into fiber because of its low solubility (standard wet spinning methods require a polymer concentration of 15-20%). Many polymers can be used as the matrix polymer. For this application, polyacrylonitrile was selected. A variety of solvents can be used but dimethylacetamide was found to be the most useful. 

Applications like corrosion protection by ennobling and passivation, and manufacture of printed circuit board surfaces composed of the organic metal polyaniline (Ormecon) are based exclusively on this unique set of properties and use most of the properties in parallel. Here, this new materials class is able to offer a performance that cannot be matched by any other material or by another conductive polymer. 

Starting in 1986, we tried to coat steel that was not prepassivated, under nonelectrochemical conditions, but with a paint containing dispersed polyaniline. We wondered if some kind of corrosion protection—by whatever mechanism—could be created by an interaction between a dispersion paint and a normal metal surface. This would be, in contrast to previous approaches, a nonelectrochemically applied PAni on a non-prepassivated metal surface. In 1987, we achieved the first promising results [70]. Subsequent work (also published in various patents) confirmed the previous findings, but did not show an exciting quantum leap in corrosion protection. Moreover, it was hardly reproducible and did not convince any paint manufacturer. 

Furthermore, intrinsically conducting polymers (ICPs) such as polyanilines (PANI), polypyrroles, and polyphenylenes have been used as part of conductive composites on account of their much higher conductivity than other polymers. They are often mixed with other polymers as investigated by Taipalus (2001) and Totsra and Friedrich (2004). On the other hand Dweiri (2007) have found the addition of PANI to a composite of PP/carbon black/graphite for bipolar plates to be unsuitable for processing due to the poor thermal stability of PANI. The company Bac2 is currently the only manufacturer to use a patented electrically conductive polymer called ElectroPhen in their composite bipolar plates. 

However, despite the promise of the polyaniline polymer, its use to manufacture hollow fibre membranes that can compete commercially have so far eluded researchers in the field. This may be due to the difficulties encountered in hollow fibre spinning processes. 

The reduction of an organic polymer. The polymer which has been most successful is poly(carbon monofluonde) (CF) which can be manufactured as a high surface-area powder capable of being reduced at a high rate at a very positive potential Oxidized polyaoetytene, polypyrrole and polyaniline are other polymers which have been discussed. 

Yuan, N.Y., Ma, F.F., Fan, Y., Liu, Y.B., Ding, J.N., 2012. High conductive ethylene vinyl acetate composites filled with reduced graphene oxide and polyaniline. Composites Part A Applied Science and Manufacturing 43, 2183—2188. 

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