489 Research Article Received: 11 October 2008 Revised: 3 December 2008 Accepted: 11 December 2008 Published online in Wiley Interscience: 2 March 2009 (www.interscience.wiley.com) DOI 10.1002/pi.2557 Influence of reaction conditions on the formation of nanotubes/nanoparticles of polyaniline in the presence of 1-amino- 2-naphthol-4-sulfonic acid and applications as electrostatic charge dissipation material Hema Bhandari, a,b Vineet Bansal, a Veena Choudhary b and Sundeep K Dhawan a* Abstract BACKGROUND: Poly(1-amino-2-naphthol-4-sulfonic acid) and its copolymers with aniline are a new class of conducting polymers which can acquire intrinsic protonic doping ability, leading to the formation of highly soluble self-doped homopolymers and copolymers. Free –OH and –NH 2 groups in the polymer chain can combine with other functional groups that could be present in protective paints which can thus be successfully used as antistatic materials. RESULTS: This paper reports the formation of nanotubes of polyaniline on carrying out oxidative polymerization of aniline in the presence of 1-amino-2-naphthol-4-sulfonic acid (ANSA) in p-toluenesulfonic acid (PTSA) as an external dopant. The presence of –SO 3 H groups in the ANSA comonomer allows the copolymer to acquire intrinsic protonic doping ability. The polymerization mechanism was investigated by analysing the 1 H NMR, 13 C NMR, Fourier transform infrared and X-ray photoelectron spectra of the copolymers and homopolymers, which revealed the involvement of –OH/–NH 2 in the reaction mechanism. Scanning and transmission electron microscopy showed how the reaction route and the presence of a dopant can affect the morphology and size of the polymers. Static decay time measurements were also carried out on conducting copolymer films prepared by blending of 1 wt% of copolymers of ANSA and aniline with low-density polyethylene (LDPE) which showed a static decay time of 0.1 to 0.31 s on dissipating a charge from 5000 to 500 V. CONCLUSION: Copolymers of ANSA with aniline were synthesized in different reaction media, leading to the formation of nanotubes and nanoparticles of copolymer. Blends of 1 wt% of PTSA- and self-doped copolymers of ANSA and aniline with LDPE can be formulated into films with effective antistatic properties. c  2009 Society of Chemical Industry Supporting information may be found in the online version of this article. Keywords: conducting polymers; copolymers; nanotubes; NMR spectroscopy; self-doping; antistatic film INTRODUCTION Electrically conducting polymers represent an important class of materials with numerous potential applications in electrode ma- terials in energy storage devices, 1–3 sensors, 4,5 shielding of equip- ment from electromagnetic interference, 6–9 electrostatic charge dissipation, 10–12 organic light-emitting diodes, 13–16 anticorrosive materials, 17–20 etc. Among conducting polymers, polyaniline 21–25 is of particular interest due to easy synthesis, environmental stabil- ity and simple non-redox doping by protonic acids; also, chemical doping and undoping can reversibly control the electrical con- ductivity of the polymer. The commercial exploitation of most of the applications based on polyaniline is closely linked to the ease of its processability; however, polyaniline is insoluble in common organic solvents. Various attempts have been made to improve its processability. Copolymerization of aniline with sub- stituted anilines is one of the conventional methods to enhance the processability and solubility. Polyaniline is one of the longest studied conducting polymers, and its copolymerization with sub- stituted anilines has been extensively studied. 26–31 Copolymeriza- tion of aniline and its doping with functionalized dopants 32 are conventional methods to enhance the properties of polyaniline. ∗ Correspondence to: Sundeep K Dhawan, Polymeric and Soft Materials Section, National Physical Laboratory, Dr KS Krishnan Road, New Delhi – 110 012, India. E-mail: skdhawan@mail.nplindia.ernet.in a Polymeric and Soft Materials Section, National Physical Laboratory, Dr KS Krishnan Road, New Delhi – 110 012, India b Centre for Polymer Science and Engineering, Indian Institute of Technology, New Delhi – 110 016, India Polym Int 2009; 58: 489–502 www.soci.org c  2009 Society of Chemical Industry