Electrical and structural analysis of conductive polyaniline/polyimide blends

Conducting films of dodecylbenzenesulfonic (DBSA)-doped polyaniline/polyimi de (PANI/PI) blends with various compositions were prepared by solvent cast ing followed by a thermal imidization process. Electrical and physical prop erties of the blends were characterized by infrared spectroscopy, an X-ray diffraction technique, thermal analysis, a UV-vis spectrophotometer, a diel ectrometer, and conductivity measurements. The blends exhibited a relativel y low percolation threshold of electrical conductivity at 5 wt % PANI conte nt and showed higher conductivity than that of pure DBSA-doped PANI when th e PANI content exceeded 20 wt %. A lower percolation threshold and a lower compatibility was shown between the two components in the blends than those of PANI-camphorsulfonic acid/polyamic acid (PANI-CSA/PAA). A well-defined layered structure due to the alignment of the long alkyl chain dopant perpe ndicular to the PANI main chain was evidenced by WAXD spectra. (C) 1999 Joh n Wiley & Sons, Inc.