Resorcinol-based phthalonitrile, 1,3-bis(3,4-dicyanophenoxy)benzene, has been synthesized in high yield by a simple nucleophilic displacement of a nitro-substituent from 4-nitrophthalonitrile in a dipolar aprotic solvent. The monomer can be thermally polymerized to a network polymer in the presence of an amine curing additive. The resin is readily processed in a controlled manner as a function of temperature and quantity of additive. Thermal analyses and rheology studies were used to characterize the high temperature thermosetting phthalonitrile polymer. Published by Elsevier Ltd.