Synthesis and Characterization of a Terpolymer Derived from Styrene, Methyl Styrene, and Polyaniline and Its Organoclay Nanocomposite Mojtaba Abbasian, 1 Mehdi Jaymand, 1 Solmaz Esmaeily Shoja Bonab 2 1 Laboratory of Chemistry Research, Faculty of Science, Payame Noor University, Tabriz, Iran 2 Laboratory of Materials, Faculty of Engineering, Islamic Azad University, Bonab branch, Bonab, Iran Received 4 February 2010; accepted 27 July 2011 DOI 10.1002/app.35391 Published online 28 December 2011 in Wiley Online Library (wileyonlinelibrary.com). ABSTRACT: A synthetic route for the preparation of a novel solution terpolymer derived from styrene, methyl sty- rene, and polyaniline (PANI) and its organoclay nanocom- posite with conductive and mechanical properties is demonstrated. Soluble PANI was synthesized by the incor- poration of brominated poly(styrene-co-methyl styrene) onto the emeraldine form of PANI. Styrene-co-methyl styrene copolymer was synthesized via nitroxide-mediated living radical polymerization by 2,2,6,6-tetramethylpiperidinyloxy iniferter and then was brominated with N-bromosuccini- mide. The solution terpolymer derived from styrene, methyl styrene, and PANI was synthesized through the N-grafting reaction of deprotonated PANI and brominated terpolymer. Nanocomposites of the terpolymer with modified montmo- rillonite were prepared with a solution intercalation method. The conductivity of the terpolymer was measured by the four-point probe method. The structures of the inter- mediate, terpolymer, and nanocomposite were investigated by Fourier transform infrared spectroscopy, 1 H-NMR, and X- ray diffraction techniques. The molecular weight of the ter- polymer was determined by gel permeation chromatography. Their thermal behavior was examined by differential scan- ning calorimetry and thermogravimetric analyses. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 125: E131–E140, 2012 Key words: conducting polymers; graft copolymers; living polymerization; nanocomposites; polymer synthesis and characterization INTRODUCTION Polyaniline (PANI) has received extensive attention in recent years because of its good electrical conduc- tivity, stability under ambient conditions, and con- trollability of its electronic and optical properties through variation of the degree of oxidation and protonation. 1 It has been used in applications such as organic, lightweight batteries, 2 microelectronics, 3 electrorheological fluids, 4 and chemical sensors. 5,6 However, like many other conducting polymers, unsubstituted PANI is intractable and suffers from poor processability, mainly because of its rigid and highly conjugated backbone. Several methods have been adopted to overcome their poor processability. For example, self-doped PANI with sulfonic acid groups substituted onto the polymer were synthesized. 7 Several ring- and N-substituted PANIs, soluble in com- mon organic solvents, were prepared directly from the polymerization of the corresponding aniline mono- mers. 8 The incorporation of side groups into PANI enhanced its solubility and processability and changed its properties. 9 Hosseini 10 reported the growing of ani- line onto functionalized polystyrene (PSt). Another approach toward soluble PANI was the copolymeriza- tion of aniline with suitable substituted aniline to pro- duce copolymers. The obtained copolymers had improved in solubility. 11 To improve the melt and solu- tion processability, the majority of PANI modifications to date have been made by the incorporation of sub- stituents on the polymer backbone. 12 Flexible alkyl chains, 13 poly(ethylene glycol) chain, 14 and polyether chain 15 have been incorporated onto PANI through the N-alkylation method. Furthermore, when PANI has been compounded with inorganic nanoparticles, the PANI composites have usually exhibited more special properties than pure PANI. 16 For example, PANI/ Fe 3 O 4 nanocomposites were more promising electro- magnetic wave absorbers than pure PANI and pure Fe 3 O 4 particles. 17 PANI with the addition of MnO 2 and ZrO 2 nanoparticles could change to be water-dispersi- ble. 18 Also, PANI/TiO 2 nanocomposites 19 had high pie- zoresistivity, and PANI that was inserted between sili- cate layers could be easily oxidized and polymerization initiated in an electronic field because the presence of the negatively charged silicate layers stabilized the radi- cal cation and promoted the polymerization. 20–22 Correspondence to: M. Abbasian (m_abbasian20@yahoo. com or m_abbasian@pnu.ac.ir). Contract grant sponsors: Iran National Science Foundation, Tabriz Payame Noor University. Journal of Applied Polymer Science, Vol. 125, E131–E140 (2012) V C 2011 Wiley Periodicals, Inc.