Conducting polyaniline (PANi) finds applications in such areas as batteries, electrochromic display devices, molecular electronics, non-linear optics, sensors, antistatic coatings, etc. [1-3]. All these applications primarily depend on the structural evolution during the polymerization process. This suggests a need for clear understanding of the local order in the polymer chain. Aniline is easily polymerized and doped to produce different states of PANi. It has recently been shown [4, 5] that the degree of order has a strong influence on the electronic state of the doped polymer. Additionally, these changes can influence electrochemical and diffusion processes which have a key role in the utility of this class of materials. Hence, imparting crystalline order in the polymer during its formation forms the primaiy focus of research. To obtain highly crystalline polymer, the structural features of the macromolecular chain have to be controlled in such a way that the conformation and packing of the conjugated polymer leads to crystalline order. Although various strategies have been reported for obtaining semicrystalline PANi, attempts to direct the polymerization process in controlled media such as microemulsion is another approach through which the growth of polymer chains can be regulated [6-9] to achieve higher crystalline order. In fact, during the course of our present investigations, we have found that microemulsion-derived PANi possesses a higher degree of crystallinity.
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