Polystyrene polyaniline

Polypyrrole/poly(ethylene-co-vinyl acetate) conducting composites with improved mechanical properties were prepared by a similar method [167], In addition, polyaniline/polystyrene [168] and polyaniline/poly(alkyl methacrylate) [169] composites have been synthesised. A solution of persulphate in aqueous HC1 was added to an o/w HIPE of polymer and aniline in an organic solvent, dispersed in aqueous SDS solution, causing aniline polymerisation. Films were processed by hot- or cold-pressing. 

M. Diaz, N.J. Pinto, J. Gao, and A. G. MacDiarmid, Electrospinning nanofibers of polyaniline and polyaniline/(polystyrene and polyethylene oxide) blends, National Conference of Undergraduate Research, University of Kentucky, Lexington (2001). 

Y. Zhu, J. Zhang, Y. Zheng, Z. Huang, L. Feng, and L. Jiang, Stable, superhydrophobic, and conductive polyaniline/polystyrene films for corrosive environments, Adv. Fund. Mater., 16, 568-574 (2006). 

Similarly, Aussawasathien et al. [185] compared the performance of CSA-doped polyaniline-polystyrene electrospun nanofibers with a thin film of the same composition for the electrochemical detection of hydrogen peroxide. As expected, the thin-film sensor showed significantly weaker currents than those of the electrospun nanofibers, with both materials showing a linear response of the redox current as a function of hydrogen peroxide concentration. However, the electrospun nanofiber sensor showed a much higher sensitivity, as evidenced by the greater slope. It was also shown that the detection of... 

Ruckenstein, E. and Yang, S. (1993) An emulsion pathway to electrically conductive polyaniline-polystyrene composites. Synth. Met., 53,283-292. 

Segal, E., Haba, Y, Narkis, M., and Siegmann, A. (2001) On the structure and electrical conductivity of polyaniline / polystyrene blends prepared by an aqueous-dispersion blending method./. Polym. Sci. Part B Poly. Phys., 39, 611-621. 

Sakharov IY, Vorobiev AC, Leon JJC (2003) Synthesis of polyelectrolyte complexes of polyaniline and sulfonated polystyrene by palm tree peroxidase. Enzyme Microb Technol 33 661-667... 

FIGURE 1.2. Molecular structure of widely used it-conjugated and other polymers (a) poly(para-phenylene vinylene) (PPV) (b) a (solid line along backbone) and it ( clouds above and below the a line) electron probability densities in PPV (c) poly(2-methoxy-5-(2 -ethyl)-hexoxy-l,4-phenylene vinylene) (MEH-PPV) (d) polyaniline (PANI) (d.l) leucoemeraldine base (LEB), (d.2) emeraldine base (EB), (d.3) pernigraniline base (PNB) (e) poly(3,4-ethylene dioxy-2,4-thiophene)-polystyrene sulfonate (PEDOT-PSS) (f) poly(IV-vinyl carbazole) (PVK) (g) poly(methyl methacrylate) (PMMA) (h) methyl-bridged ladder-type poly(jf-phenylene) (m-LPPP) (i) poly(3-alkyl thiophenes) (P3ATs) (j) polyfluorenes (PFOs) (k) diphenyl-substituted frares -polyacetylenes (f-(CH)x) or poly (diphenyl acetylene) (PDPA). 

The basic structure of a typical dc-biased bilayer OLED is shown in Figure 1.5. The first layer above the glass substrate is a transparent conducting anode, typically indium tin oxide (ITO). Flexible OLEDs, in which the anode is made of a transparent conducting organic compound, e.g., doped polyaniline (see Fig. 1.2),44 or poly(3,4-ethylene dioxy-2,4-thiophene) (PEDOT)-polystyrene sulfonate (PEDOT-PSS) (see Fig. 1,2)45 deposited on a suitable plastic, e.g., transparency plastic, have also been reported. 

Since multiple electrical and optical luiiclioiialily must be combined in the fabrication of an OLED, many workers have turned to the techniques of molecular self-assembly in order to optimize the microstructure of the materials used. In turn, such approaches necessitate the incorporation of additional chemical fimctionality into the molecules. For example, the successive dipping of a substrate into solutions of polyanion and polycation leads to the deposition of poly-ionic bilayers [59, 60]. Since the precursor form of PPV is cationic, this is a very appealing way to tailor its properties. Anionic polymers that have been studied include sulfonated polystyrene [59] and sulfonated polyaniline [59, 60]. Thermal conversion of the precursor PPV then results in an electroluminescent blended polymer film. 

I. Oxidoreducates Oxidation or reduction Peroxidase Laccase Polyanilines, Polyphenols, Polystyrene, Polymethyl methacrylate 6, 7, 8,13, 15... 

In Chapter 6 the enzymatic polymerization of vinyl monomers is presented. Polymers, such as polystyrene and poly(meth)acrylates can be readily polymerized under catalysis of oxidoreductases like peroxidases, oxidases, etc. In addition oxidoreductases can be used to polymerize phenolic monomers (Chapter 7) and even to synthesize conducting polymers such as polyaniline (Chapter 8). 

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