Polyaniline dispersion

Methods of filler pretreatment none reported but the type of filler plays essential role in obtaining stable polyaniline dispersion... 

J. Stejskal, M. Spirkova, A. Riede, M. Helmstedt, P. Mokreva and J. Prokes, Polyaniline dispersions 8. The control of particle morphology, Polymer, 1999, 40, 2487. 

In those days, we were interested in coating metals like bare iron, steel, stainless steel or other metals non-electrochemically by using polyaniline dispersions or polyaniline containing lacquers. The first experiments had shown that some improvement in corrosion protection could be obtained [109], Further progress in lacquer formulation had been the basis for quite successful long-term salt spray studies [110], but the effects observed in this practical test have not been convincing for corrosion protection experts. 

In contrast to earlier [109,110] procedures, polyaniline was deposited from pure polyaniline dispersions [111]. 

Following this, in a joint project lasting several years, we investigated over a broad concentration range, the conductivity of polyaniline dispersed in a thermoplastic matrix. The results were confirmed, in quantitative terms as well as the metallic properties and the dimensions (9.6 nm) of the PAni primary particles, which contain a metallic core of 8 nm [68]. 

Fig. 5.40. NIR spectra of a polyaniline dispersion prepared with various concentrations of aniline (dispersion prepared according to [146] for further details, see [146])...

Stejskal, J., T. Sulimenko, et al. (2000). Polyaniline dispersions 10. Coloured microparticles of variable density prepared using stabilizer mixtures. Colloid Polymer Science 278(7) 654-658. 

A further advantage of polyaniline dispersion coatings and complete coating systems including interlayers and topcoats is its applicability to metal substrates other than steel. Aluminum is subject to so-called filiform corrosion, which can be effectively beaten by suitable products, in this case CORRPASSIV 4901 (a different kind of primer and top coat) the performance was tested by an independent institute (see footnote 7). In the meantime, the same primer was also successfully tested in various applications on magnesium. 

The copper substrate was a sputter-cleaned pure copper foil. On exposure of the copper foil to air, polyaniline was deposited onto it using a commercially produced polyaniline dispersion in an organic solvent (Ormecon GmbH). The sample was kept in air at room temperature and after a certain time in air was transferred back into the main chamber for analysis. XPS measurements were performed using... 

The commercially available, stable polyaniline dispersion for the spin coating of HILs—the developmental type Covion PAT 010—has a particle size distribution of the water-based PAT 010 compared to commercially available PEDT samples as shown in Figure 1.47. 

Adhikari, A., Claesson, P., Pani,)., Leygraf, C., Deidinaitei, A., and Blomberg, E. (2008) Electrochemical behavior and anticorrosion properties of modified polyaniline dispersed in polyvinylacetate coating on carbon steel. Bectrochim. Acta, 53,4239-4247. 

Chattopadhyay, D. and Mandal, B.M. (1996) Methyl cellulose stabilized polyaniline dispersions. Langmuir, 12, 1585-1588. 

Stejskal, J., Kratochvil, P., and Hehnstedt, M. (1996) Polyaniline dispersions. 5. Poly(vinyl alcohol) and poly(N-vinylpyrrolidone) as steric stabilizers. Langmuir, 12, 3389—3392. 

Ormecon Ormecon Chemie, Germany Polyaniline dispersions Corrosion protection, antistatic coatings... 

Oil-in-oil emulsion systems display a relatively strong ER effect. Examples of such ER active emulsions are chlorinated paraffin/polydimethylsiloxane [11], castor oil/polydimethylsiloxane [13], urethane-modified polypropylene glycol/dimethylsiloxane [12] etc.. The ER effect in emulsions is attributed to the stretched droplets that Ibrm fibrillation chains along the direction of the electric field. This is a typical feature for any emulsion system in which the two liquids have a quite different dielectric constant and conductivity. Figure 17 shows the water droplet chains formed in a supercritical fluid carbon dioxide medium under a 60 Hz ac field of a very low field strength, Emax=IO V/mm [115]. A synergetic effect is observed in an system composing of polyanilines dispersed in a chlorinated paraffin/silicone oil emulsion [107],... 

Deposition on fibers or fabrics Vapor phase deposition Deposition in nanoscale matrices Photochemically initiated polymerization Enzyme-catalyzed polymerization Polymerization using electron acceptors Miscellaneous polymerization methods Routes to more processible polyanilines Emulsion polymerization Colloidal polyaniline dispersions Substituted polyanilines... 

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