Journal of Applied Polymer Science, Vol.115, No.4, 2271-2276, 2010
Patterned Conductive Polyaniline Films Fabricated Using Lithography and In Situ Polymerization
In this article, we describe a novel bottom-up technique for the preparation of transparent conductive films of polyaniline (PANI). A UV-curable photoresist was formulated containing an acrylate-endcapped urethane oligomer [UA(PPG400)], acrylic acid, a photoinitiator, and a reactive diluent (tripropylene glycol diacrylate), and the lithography techniques were used to pattern the structure with line widths/spaces of 100 mu m/100 mu m, 10 mu m/10 mu m, and 5 mu m/5 mu m on a polyethylene terephthalate substrate. The carboxylic acid units on the surface of the patterned photoresist interacted with the aniline monomer units to form anilinium complexes; using ammonium persulfate as a chemical oxidant, we then synthesized a layer of conductive PANT on the surface of the patterned resist through in situ polymerization. The optimal conductivity of the PANI conductive film was ca. 10 S/cm. The thin film was characterized, and its physical properties investigated using Fourier transform infrared spectroscopy, UV-Vis spectroscopy, differential scanning calorimetry, optical and atomic force microscopy, and four-point probe conductivity measurements. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 115: 2271-2276, 2010