Conjugated polymer fibers

Chuangchote S, Fujita M, Sagawa T, Stikaguchi H, Yoshikawa S (2010) Control of self organization in conjugated polymer fibers. ACS Appl Mater Interfaces 2 2995-2997. doi 10.1021/aml008198... 

The rigid chemical structure of a conjugated polymer helps in the movement of electrons. That stiff structure, however, has limited its use. They are like uncooked spaghetti and do not easily entangle themselves. Polymer chain entanglements are necessary to achieve high viscosities, which are required to create fibers out of these polymers. 

Yoon J, Chae SK, Kim J-M. Colorimetric sensors for volatile organic compounds (VOCs) based on conjugated polymer-embedded electrospun fibers. J Am Chem Soc 2007 129 3038-3039. 

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... 

J. Yoon, Y.-S. Jung, and J.-M. Kim, A combinatorial approach for colorimetric differentiation of organic solvents based on conjugated polymer-embedded electrospun fibers, Adv. Funct. Mater., 19, 209-214 (2009). 

In conclusion, polymers play a versatile role in the field of chemosensors. Most interestingly, certain polymers can actively serve as sensors. This pertains to certain strongly fluorescent conjugated polymers, as pointed out above, and to polymers employed as cladding for optical fibers in evanescent wave-based sensors. Moreover, polymers are widely used as supports for transducers, which are either admixed or chemically linked to the polymer matrices. Typical examples are given in the following sections. 

A polymer whisker is a spontaneously formed assembly with a higher-ordered structure and could be used as a single fiber for amplification of the intrinsic properties of the polymer. The whiskers of aromatic polyesters such as poly(para-oxybenzoyl) and poly(2-oxo-6-naphthoyl) have been intensively investigated [31, 32], while there have been only few reports on the whiskers of conjugated polymers such as poly(3-alkylthiophene) [33]. When a helical conjugated polymer with a whisker structure is designed, the intrachain and interchain interactions must be balanced by precisely controlling the van der Waals, rr-electron overlap, and electrostatic interactions. 

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