Conjugated electrospinning

Conjugate electrospinning set-up. Image kindly supplied by Xinsong Li. 

Other studies in 2000 by Drew et al. reported that it is very difficult to spin fibers of PANI complexed to sulfonated polystyrene (PANFSPS), even when solutions containing sodium chloride and dodecyl benzene sulfonic acid sodium salt were used to lower the surface tension and thereby enhance electrospinning [16,17]. However, PANFSPS nanofibers can be produced by adding a carrier polymer such as PEO, polyacrylonitrile, or polyurethane. Also reported was the use of electrostatically layered sulfonated polystyrene as a template for the surface polymerization of conjugated polymers in their conducting form. Enzymatic synthesis of PANI and a copolymer of pyrrole and PEDOT was done on electrospun nanofiber... 

Poly[2-methoxy-5-(2 -ethyl-hexyloxy)-l,4-phenylene vinylene] (MEH-PPV) is an excellent conjugated polymer and broadly used in polymer photoelectron devices, but is difficult to electronspin directly. In the work by Zhao et al, core-shell structured nanofibers were fabricated by coaxial electrospinning MEH-PPV (shell) in chlorobenzene and PVP (core) in 1,2-dichloroethane [64]. MEH-PPV was soluble in the above two solvents, which prevented the precipitation of MEH-PPV and enhanced the adhering action between the two polymers in the coaxial electrospinning process. It should be noted that this is an unusual example of core-shell nanofibers where (a nonprocessable) PPV was spun as the shell and not in the core. These uniform core/shell PVP/MEH-PPV nanofibers with a highly fluorescent property can have potential applications in the fabrication of polymer nanophotoelectron devices. 

There are several techniques that allow to produce polymeric nanofibers, such as drawing, template synthesis, phase separation, self-assembly, solution blow spinning, and electrospinning. The drawing process requires a polymer with appropriate viscoelastic properties that is able to be deformed and kept connected by cohesive forces. Besides being simple and inexpensive, this technique is very limited for conjugate polymers, since most of them have lower solubility and form solutions with a small viscous modulus. 

Figure 6.18 Electrospinning (DMF] solution with and without conjugated polymer (PAN, PANA/PAN], and nanofiber and electrospinning scheme. Reprinted with permission from Ref. 190, Copyright 2013 Elsevier Ltd.

There are various methods to synthesize polymer nanostructures, i.e., template synthesis, chiral reactions, self-assembly, interfacial polymerization and electrospinning. Recent developments in conducting polymer nanotubes and nanofibers were summarized by Long et al. Different preparation methods, physical properties, and potential applications of one-dimensional nanostructures of conjugated polyaniline (PANI), pol5 3nrole (PPy) and poly (3, 4-ethylenediox3d hiophene) (PEDOT) were discussed. 

This book covers the general aspects of electrospinning and discusses the fundamental concepts that can be used to produce nanofibers with the help of mathematical models and equations. It also details the methods through which different polymeric structures can be included in conjugated polymers during electrospinning to form composites or blends of conjugated polymer nanofibers. 

This book covers general aspects, fundamental concepts, and equations of electrospinning used for the production of nanofibers and reviews latest researches on inclusion of conjugated polymer in different polymeric structures such as composites or blends of conjugated polymer nanofibers obtained by electrospinning. 

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