Synthesis and cross-linking of poly(ether-ketone)s, and poly(ether-ketone-sulphone)s with pendant nitrile groups (II)

A number of new poly(ether-ketone)s and poly(ether-ketone-sulphone)s are synthesized by polycondensation of (a) benzofuro[2,3-b]benzofuran-2,9-dicarbonyl chloride (1), (b) equimolar mixture of 1 and 4,4'-[sulphonyl bis(p-phenyleneoxy)] dibenzoyl chloride (11), and (c) 2,7-biphenylene dicarbonyl chloride (111) with 2,6-diphenoxy benzonitrile and a number of diaryl ethers through indirect polycondensation in the presence of aluminum chloride as catalyst. Molecular structures were confirmed by FTIR spectroscopy and elemental analysis data. Because of the presence of nitrile groups along the polymer chain, the polymers were cross-linked. Thermal properties before and after cross-linking were investigated by TGA and DSC methods.