Polyaniline networks

FIGURE 9.2. Schematic structure of a bilayer device with conducting polyaniline network electrode. 

Hu, H., K. Zhang, S. Li, S. Ji, and C. Ye. 2014. Flexible, in-plane, and all-solid-state micro-supercapacitors based on printed interdigital Au/polyaniline network hybrid electrodes on a chip. Journal of Materials Chemistry A 2 20916-20922. 

The difference in the ratio is accounted for as follows. Two coordination sites are available with Pd(OAc)2 or PdCl2(MeCN)2, but the complex 3 bearing the tri-dentate ligand has only one free coordination site. A cross-linked polyaniline network complex 4 is considered to be formed in the former case. On the contrary, the latter complexation affords the single-strand conjugated complex 5. Thus, a hybrid system composed of transition metals and 7C-conjugated polymers is controlled structurally (Fig. 3.11). 

Komathi S, Gopalan AI, Lee KP. Covalently linked silica-multiwaU carbon nanotube-polyaniline network an electroactive matrix for ultrasensitive biosensor. Biosens Bioelectron 2009 25(4) 944-947. 

ZnO displays similar redox and alloying chemistry to the tin oxides on Li insertion [353]. Therefore, it may be an interesting network modifier for tin oxides. Also, ZnSnOs was proposed as a new anode material for lithium-ion batteries [354]. It was prepared as the amorphous product by pyrolysis of ZnSn(OH)6. The reversible capacity of the ZnSn03 electrode was found to be more than 0.8 Ah/g. Zhao and Cao [356] studied antimony-zinc alloy as a potential material for such batteries. Also, zinc-graphite composite was investigated [357] as a candidate for an electrode in lithium-ion batteries. Zinc parhcles were deposited mainly onto graphite surfaces. Also, zinc-polyaniline batteries were developed [358]. The authors examined the parameters that affect the life cycle of such batteries. They found that Zn passivahon is the main factor of the life cycle of zinc-polyaniline batteries. In recent times [359], zinc-poly(anihne-co-o-aminophenol) rechargeable battery was also studied. Other types of batteries based on zinc were of some interest [360]. 

Polymer nanofiber networks consisting of achiral polyaniline were prepared by Epstein et al. (3) by oxidizing aniline with ammonium peroxydisulfate and then doping with methanesulfonic acid. 

Conducting polymer blends based upon polyaniline (PANI) are a new class of materials in which the percolation threshold for the onset of electrical conductivity can be reduced to volume fractions well below that required for classical percolation (16% by volume for globular conducting objects dispersed in an insulating matrix in three dimensions) [277,278], The origin of this remarkably low threshold for the onset of electrical conductivity is the self-assembled network morphology of the PANI poly blends, which forms during the course of liquid-liquid phase separation [61],... 

Michira, I. N. Klink, M. R.O. Akinyeye Somerset, V. M. Sekota Al-Ahmed, A. P.G.L. Baker Iwuoha, E. I. In Recent advances in analytical electrochemistry Anthracene sulfonic acid-doped polyanilines electrodynamics and application as amperometric peroxide biosensor Kenneth, O. Ed. Chapter 5 Transworld Research Network Karala India, 2007 Vol., pp. 137. 

The chain ends of the star polymers can be functionalized. So it is possible to link these sites and form networks or gels of stars. Depending on the chemical nature of the chain end, the crosslinking can be permanent or stimuli-switchable. Patrick-ios et al. [105] have prepared crosslinked double hydrophilic star copolymers made from methacrylic acid (MAA) and poly(ethyleneglycol methacrylate) (PEGMA). Meyer et al. [106] synthesized photocrosslinkable PMAA stars, which could serve as well-defined model polyelectrolyte networks. The polyelectrolyte stars can also be used as template for some nanomaterials. Want et al. [107] prepared strong anionic polyelectrolyte stars by sulfonation of the PS stars. They were used as the template for the preparation of conducting polyaniline. 

In this model, the polyaniline chain is assimilated to a series network of parallel resistances and capacitances (Figure 8.21). The resistances./ (/) and the capacitances C(0 will correspond to the emeraldine salt part (the conductive part) and will depend on the emeraldine salt segments length /. The resistance / (/ ) and the capacitances C (/ ) correspond to the emeraldine base part (the insulating part) and depend on the emeraldine base segments length /. 

Figure 11.2. With the scanning tunnelling microscope, dispersed polyaniline (PAni) can be shown to consist of primary particles that are no larger than 10 nanometres (millionths of a millimetre). In (a) they can be seen as light, yellow-coloured patches. Once the volume concentration exceeds a critical threshold, these flocculate and—as can be seen in the scanning electron micrograph (b)—form network-like strucmres. Each of the particles behaves like a metal measuring a few nanometres, i.e. it possesses freely mobile electrons. These can tunnel between the particles and thereby conduct electricity. [Reproduced from ref. 17b with kind permission from Gordon and Breach publishers.]...

Ram M. K. and Nicolini C., Supramolecular engineering and applications of polyanilines, in Supramolecular Engineering of Conducting Materials, ed. M. K. Ram (Trivandrum, Kerela, India Transworld Research Network, Research Signpost, 2005). 

In 2008 the same authors reported the synthesis of polyaniline-type size-selective hypercrosslinked network polymers [262]. According to the developed protocol, leucoemeraldine polyaniline and diaminobenzene were coupled with diiodobenzene and tribromobenzene. The resulting... 

Chapters 7-9 form the second part and describe the hypercrosshnked polystyrene networks. These chapters cover in detail the basic principles of the formation of hypercrosshnked polymers, the synthesis of hypercrosshnked networks and also the properties and morphology of the polystyrene networks. Characterization techniques such as electron microscopy and X ray scattering are also covered. Hypercrosshnked polymers like polysuhbne, polyarylates or polyanilines among others are also reported on as a novel class of polymeric materials. 

Studies performed by Yuan et al. on conductive polyaniline (PANI) nanofibers, P3DOT, and CNT thin films show that aU three are capable of forming highly compliant electrodes with fault tolerant behavior [225]. Nanowires and tubes are of particular interest since they are capable of maintaining a percolation network at large strains, thus reducing the required electrode thickness while still allowing for maximum strain performance. 

W. Zhong, J. Deng, Y. Yang, and W. Yang, Synthesis of large-area three-dimensional polyaniline nanowire networks using a soft template , Macromol. Rapid Commun., 26, 395-400 (2005). 

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