A series of electroactive aromatic polyimides with (4-morpholinyl)triphenylamine units in the backbone were prepared from a newly synthesized diamine monomer, 4,4'-diamino-4 ''-(4-morpholinyl)triphenylamine, and aromatic tetracarboxylic dianhydrides via the conventional two-step polycondensation technique. Flexible and tough polyimide films could be obtained via the thermal curing of their precursor poly(amic acid) films. The polyimides showed high glass-transition temperatures (T-g) between 290-313 degrees C, and they did not show significant decomposition before 500 degrees C in air or nitrogen atmosphere. Cyclic voltammograms of the polyimide films on the indium-tin oxide (ITO)-coated glass substrate exhibited a pair of reversible oxidation waves with low onset oxidation potentials of 0.43-0.53 V (vs. Ag/AgCl) in acetonitrile solution. They also exhibited multicolor electrochromic behavior between their neutral and oxidized states changing from pale yellow to cyan and bluish purple. (C) 2016 Elsevier B.V. All rights reserved.