Synthesis and characterization of polyarylureas. I. Potentially semiconducting polymers

Polyarylureas were synthesized from the reaction between phosgene with arom atic diamines. Depending on the pH, the polyarylureas presented different c olors when the solvent used was pyridine. The polyarylureas were characteri zed by IR spectroscopy, elemental analysis, and X-ray photoelectron spectro scopy (XPS). To study the thermal stability of the polymers, a thermal degr adation was performed between 35 and 700 degreesC. The polyarylureas decomp osed above 350 degreesC. Without doping, polyarylureas are considered as se miconductors [sigma = 10(-9) (Omega cm)(-) (1)]; after doping with I-2, the ir electrical conductivity increases by several orders of magnitude. (C) 20 01 John Wiley & Sons, Inc.