Poly(quinoxaline-2,3-diyl)s bearing alkoxy pendants was synthesized by living polymerization of 4,5-dialkoxy-3,6-dimethyl-1,2-diisocyanobenzenes, which were easily accessible from 3,6-dimethylcatechol, using organonickel complexes as initiators. Thermal properties of the obtained polymers were fully determined by thermogravimetric analysis and differential scanning calorimetry, exhibiting strong dependence on their side chains. (C) 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 4275-4282, 2011