Schiff base polymers derived from 2,5-diformylfuran

Polymerization of 2,5-diformylfuran with two primary amines was carried out in acetonitrile and ethanol at room temperature. The reaction was characterized using a combination of mass spectroscopy and NMR spectroscopy, which revealed the clean formation of the imine -CH N-functional group. Although some cyclic products were detected from mass spectroscopy, the ring size was limited to products that have the -CH N-group only in anti-geometry. The furan Schiff bases exhibit good thermal stability. While mass spectra evidenced oligomers of different lengths, cross-polarization magic angle spinning 13C NMR spectra of the insoluble polymer revealed the linear structure as proposed. (C) 2013 Society of Chemical Industry