Study on the effect of acid- or iodine-doping on the properties of copolymer C1-4poly-phenylene-vinylene-ether

In this article, the new red-colored copolymer, referred to as C(1-4)polyphenylene-vinylene-ether (C1-4PPV-ether) is built as a PPV polymer with some conjugated links (-CH=CH-) that are changed into ethylic-ether links (-CH2-O-CH2-) and whose modified phenyl ring is grafted, respectively, in two and five positions with methoxy and butoxy groups. The C1-4PPV-ether is doped with protonic acid or iodine. The infrared absorption (IR), optical density, X-ray photoelectron spectroscopy (XPS), and electron spin resonance (ESR) show that there is a charge transfer complex formed between the copolymer and the doping species (iodine or acidic dopants). From IR, XPS, and ESR analysis, we deduced that the doping mechanism of the copolymer is, respectively, a protonation of the double links in PPV in the case of the protonic acid doping process and a grafting of the iodine to the ether links in the case of iodine-doping process. (C) 2002 Wiley Periodicals, Inc.