Chromatographical investigation and mass spectrometry of cyclic polyimides by matrix-assisted laser desorption

The Diels-Alder addition polymerization of bispyrone 1 with 2 mol bismaleimide 2 was shown to lead to cyclic polyimides 3 (64%, M̄_n = 15 000 g/mol) and to cyclic oligomers (36%) applying by gel-permeation chromatography analysis (GPC) and by means of matrix-assisted laser desorption/ionisation technique (MALDI).