This paper describes the synthesis of new model compounds and copolyether sulphones with different reactive chain-ends from the OH and NH2 ends which are well documented for this type of polymer. These materials were characterised by H-1 NMR, Fourier transformed infrared (FTIR) spectroscopy and elemental analysis. They are seen to have potential applications both in the chain-extension of low molecular weight thermoplastics and in the preparation of well-defined block copolymers.