Organic soluble and conducting polyaniline (PANI)-grafted multiwalled carbon nanotube (MWNT) nanocomposites were synthesized by in situ emulsion polymerization. Dodecyl benzene sulfonic acid (DBSA) acted as both a dopant and emulsifier, and phenylamine groups grafted on the surface of the MWNTs via amide bonding joined in the in situ polymerization. As self-assembly templates, multiwalled carbon nanotubes containing phenylamine groups (p-MWNTs) were encapsulated by PANI to form a homogeneous core (p-MWNTs)-shell (DBSA-doped PANT) nanostructure. The attachment of soluble DBSA-doped PANT chains on the surface of the p-MWNTs via covalent bonding rendered the p-MWNTs compatible with the polymer matrix and led to the nanocomposite being highly soluble and stable in tetrahydrofuran. The PANT chains grew restrictively on the surface of the p-MWNTs, and the crystalline orders of the PANI coatings were enhanced. Because of the incorporation of the p-MWNTs, the thermal stability of the nanocomposites was improved, and the conductivity of the nanocomposites at room temperature was increased by at least one order of magnitude over neat DBSA-doped PANT. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 118: 2582-2591, 2010