Polymer(Korea), Vol. 34, No. 6, pp 553-559, 2010 553 Introduction Polyaniline (PANI) has been the subject of considerable recent interest because of their unique properties such as high electrical conductivity, good environmental stability in doped and neutral states, 1 ease of synthesis and numerous potential applications including rechargeable batteries, 2-4 energy storage devices, electromagnetic interference shiel- ding, electronic and optical devices, 5,6 smart windows and light emitting diodes. 7 However polyaniline is inherently brittle and poor in processability due to its insolubility in common organic solvents. Its poor solubility has limited the industrial applications of polyaniline. 8,9 To improve its processability, various procedures have been adapted. For example, self doped PANI with sulfonic acid groups substituted onto the polymer has been synthesized. Several ring and N-sub- stituted PANI, soluble in common organic solvents, have been prepared directly from polymerization of the corresponding aniline monomers. 10 Another approach toward modified poly- aniline is copolymerization of aniline with suitable substituted aniline to produce copolymers. The obtained copolymers have improved in solubility and processability. 11 Among PANI derivatives, sulfonated polyaniline (SPANI) is the most successful candidate for practical applications in electronic devices due to its water solubility, electroactive properties, thermal stability, optical properties, unique self-doping and external doping mechanism. 12-14 However, strong electron- withdrawing of sulfonic acid's functional groups make con- ductivity of SPANI much lower than that of PANI. 15 In recent years, “controlled/living” radical polymerization (CRP), have developed rapidly for facile preparation of a variety of polymeric materials with predetermined molecular weight (M n ) and low polydispersity index (PDI), and high degrees of chain-end functionalization. 16 Compared with NMRP 중합법을 이용한 전도성 폴리아닐린-수식 고분자의 제조와 특성 Mehdi Jaymand Lab. of Polymer, Faculty of Chemistry, Payame Noor University, Tabriz-Iran (2010년 6월 10일 접수, 2010년 7월 18일 수정, 2010년 8월 20일 채택) Synthesis and Characterization of Conductive Polyaniline-Modified Polymers via Nitroxide Mediated Radical Polymerization Mehdi Jaymand Lab. of Polymer, Faculty of Chemistry, Payame Noor University, Tabriz-Iran (Received June 10, 2010; Revised July 18, 2010; Accepted August 20, 2010) Abstract: The paper describes the preparation and characterization of conductive polyaniline-modified polymers by growing of aniline onto functionalized poly(styrene-co-p-methylstyrene) [P(St-co-MSt)]. For this purpose, P(St-co-MSt) was synthesized via nitroxide mediated radical polymerization (NMRP) and then N-boromosuccinimide was used for introduction of bromine to the benzylic positions of copolymer. Afterwards, 1,4-phenylenediamine was linked to the brominated P(St-co-MSt) and functionalized copolymer [P(St-co-MSt)-NH 2 ] was prepared. The graft copolymerization of aniline monomers onto functionalized P(St-co-MSt) was initiated by oxidized phenylamine groups after addition of ammonium peroxydisulfate (APS), and p-toluenesulfonic acid-doped PANI was chemically grafted onto P(St-co-MSt) via oxidation polymerization. The obtained terpolymer was studied by FTIR and UV-Vis spectroscopy and its thermal behaviour were examined by DSC and TGA analyses. The conductivity of terpolymer was measured by four-point probe method and electroactivity was measured by cyclic voltammetry (CV). The solubility of P(St-co-MSt)-g-PANI was examined in common organic solvents. Keywords: poly(styrene-co-p-methylstyrene), NMRP, graft copolymer, conductive polyaniline, modi- fication, solubility. † To whom correspondence should be addressed. E-mail: m_jaymand@yahoo.com , m.jaymand@gmail.com