The synthetic procedure and the characterization of the new amino derivatives of poly(oxa-p-phenylene-3,3-phtalido-p-phenylene-oxa-p-phenilene-oxy-phenylene) (PEEK-WC) with various average degrees of substitution, is reported. The amino PEEK-WC was extensively characterised by using Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis, differential scanning calorimeter, scanning electron microscopy, Elemental analyses, NMR, and viscosity measurements. The amino PEEK-WC shows different solubility in some solvents in comparison with the parent polymer, good thermal stability and is able to form membrane by means of the phase inversion technique. Amino PEEK-WC results to be quite reactive and can lead to further modification. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 117: 2258-2264, 2010