Polyaniline-graft-Poly(N-isopropylacrylamide) copolymers were synthesized by atom-transfer radical polymerization (ATRP) of N-isopropylacrylamide using polyaniline macro-initiators. Polyaniline-chloroacetylchloride and polyaniline-chloropropionylchloride macroinitiators were obtained by the reaction of amine nitrogens of polyaniline with chloroacetyl chloride and 2-choloropropionyl choloride, respectively. Both macroinitiators and graft copolymers were characterized by FT-IR and (1)H-NMR spectroscopy. The cyclic voltammetry (CV) and UV-Vis spectroscopy studies showed that these copolymers are electroactive. The solubility test revealed that the polyaniline-graft-poly (N-isopropylacrylamide) copolymers are water soluble or water/methanol soluble. The Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) images showed the growing of poly (N-isopropylacrylamide) chains on polyaniline backbone. Investigation of thermal behavior of graft copolymers by thermal gravimetry analysis (TGA) confirmed the results obtained from AFM and SEM images. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123: 2299-2308, 2012