Research Article Benzoyl Peroxide Oxidation Route to the Synthesis of Solvent Soluble Polycarbazole Rajender Boddula 1 and Palaniappan Srinivasan 1,2 1 Polymers & Functional Materials Division, Indian Institute of Chemical Technology, Hyderabad, Telangana 500007, India 2 CSIR, Network Institutes for Solar Energy (NISE), India Correspondence should be addressed to Palaniappan Srinivasan; palani74@redifmail.com Received 11 June 2014; Accepted 31 July 2014; Published 29 October 2014 Academic Editor: Miguel A. Esteso Copyright © 2014 R. Boddula and P. Srinivasan. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Carbazole was oxidized by benzoyl peroxide in presence of p-toluenesulfonic acid to polycarbazole salt at room temperature for the frst time. Polycarbazole salts were synthesized via solution and emulsion polymerization pathways. Polycarbazole bases were prepared by dedoping from polycarbazole salts. Formation of polycarbazoles was confrmed from infrared, electronic absorption and EDAX spectra. Polycarbazole salt was obtained in amorphous nature in semiconductor range (10 −5 S/cm), which was found to be soluble in less and high polar solvents. Polycarbazole salt prepared by emulsion polymerization pathway showed mixture of shapes with microrod, sphere, and pores, whereas its corresponding base showed only micropores structure. On the other hand, polycarbazole salt and its corresponding base prepared by solution polymerization pathway showed fake-like morphology. Higher thermal stability was obtained for polycarbazole salt prepared by emulsion polymerization pathway than that of the salt prepared by solution polymerization pathway. 1. Introduction Conductive polymers or, more precisely, intrinsically con- ducting polymers are organic polymers that conduct elec- tricity [1], and such compounds may have metallic conduc- tivity or can be semiconductors. Some of the well-studied organic conductive polymers, according to their composi- tion, are polyaniline, polypyrrole, polythiophene, polyacety- lene, poly(p-phenylene vinylene), poly(p-phenylene sulfde), and polycarbazole. Polycarbazole (PCz) and its derivatives, which have a structure of pyrrole ring with two fused benzene rings, are well known to exhibit good electroactive and photoactive properties [2]. PCz is being explored for various applica- tions especially in hole transporting and photoluminescence efciency, electroluminescence [3–5], light-emitting diodes [6], electrochromic displays [7], supercapacitor [8], chemical batteries [9, 10], sensors [11, 12], and laser dyes and organic transistors [13]. Studies on polycarbazole and its derivatives synthesized by electrochemical method have been reported [14–17]. How- ever, work on chemical synthesis of unsubstituted carbazole is very few, even though chemical synthesis for substituted polycarbazole had already been reported [18–20]. Chemical synthesis of PCz is drawing keen attention due to its obvious advantage in morphology control and bulk synthesis. In 2010, frst report of chemical synthesis of unsubstituted PCz in hollow microspheres morphology was reported by Gupta and Prakash [21] and Raj et al., that is, the synthesis of soluble PCz by the chemical oxidative polymerization of carbazole using ammonium persulfate in acetonitrile medium [5]. Recently, PCz-Au composite was synthesized by the oxidation of carbazole using HAuCl 4 oxidant [22]. Tere is a restriction on the selection of the oxidiz- ing agents due to nonsolubility of oxidizing agents and monomers in the same solvent. Tis problem aggravates in case of carbazole as it is insoluble in aqueous media. Since carbazole is not soluble in water and soluble in chloroform, carbazole was oxidized using chloroform soluble benzoyl peroxide oxidant by solution polymerization pathway. Also, carbazole was polymerized to polycarbazole, that is, emulsion polymerization pathway using sodium lauryl sulfate as emul- sifer. Polycarbazole was characterized by physical, electrical, spectral, and thermal methods. Hindawi Publishing Corporation International Scholarly Research Notices Volume 2014, Article ID 987236, 8 pages http://dx.doi.org/10.1155/2014/987236