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Aromatic ether-ketone segments have been incorporated into polyimide backbone to impart the well-known thermoplastic properties of polyether ketones. For this purpose three aromatic diamines containing ether and ketone connecting groups between aromatic rings have been prepared and polymerized with pyromellitic dianhydride to yield polyimides. The thermal behavior of the polyimide cast films has been investigated. ZUSAMMENFASSUNG:Aromatische Ether-Keton-Sequenzen wurden in eine Polyimidkette eingebaut, um diesen die thermoplastischen Eigenschaften der Polyetherketone zu verleihen. Zu diesem Zweck wurden drei aromatische Diamine mit Ether-und Ketongruppen zwischen den aromatischen Ringen hergestellt und mit Pyromellitsguredianhydrid kondensiert. Das thermische Verhalten von daraus hergestellten Polymerfilmen wurde untersucht.

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Reaction of epichlorohydrin with ethylenediamine is very exothermic, and severe explosions occur, even when a few milliliters of the reagents are interacted without solvent. A controlled reaction has been achieved safely by suspension polycondensation of epichlorohydrin with ethylenediamine. 1,2-Diaminoethane units in the resulting crosslinked polymer provide high chelating ability for transition metal ions, such as Cu(II), Ni(II), Co(II), Cd(II), Fe(III), and Cr(III). Having all-amine ligating groups, the polymer represents unique properties and can sorb not only metal cations but also their counteranions, such as chloride, sulphate, nitrate, and acetate. The crosslinked polymer is stable hydrolytically and regenerable by acid without losing its activity. It can be recycled and offers a means of simultaneous removal of cations and anions from aqueous solutions.