A series of high-performance polymer/carbon nanotube (CNT) composites with different nanotube contents have been prepared via condensation of N-silylated diamino terminated precursor of the polymer with acid chloride-functionalized CNTs and subsequent thermal cyclodehydration. The composites have been fully characterized by infrared and Raman spectroscopy, electron microscopy, and thermal analysis. Various interesting morphologic features including helical structures have been observed in the composites as a result of covalent attachment of the polymer. The composites exhibit excellent thermal stability and a significant improvement in the dielectric constant and mechanical strength with the inclusion of CNTs. (C) 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012