Preparation and Characterization of Polyoxetane Resins Having Aspartic Acid Moiety and Its Derivatives at the Spacer-Separated Side-Chain End

The pendant spacer-separated aliphatic primary amines of polyoxetane resins were modified by polymer reactions to give chelate resins bearing N-spacer-substituted aspartic and its hydroxamic acid moieties. The primary amines of polyoxetane resins were subjected to the Michael addition with diethyl maleate to a degree of functionality of 0.6-0.9, and the resultant aspartates were then converted to the acid moieties by alkali-hydrolysis or NH2OH-aminolysis. The corresponding anilino pendants also gave the Michael addition products, as confirmed by their IR spectra, although a model product was not obtained. The Cu (II) -adsorption capacities of the acid-containing aliphatic amino-type resins were 2.9-3.8mmolg-1, which were higher than the capacity expected for the ordinary structure of a Cu (II) ion chelated with two molecules of carboxylic or hydroxamic acids, being ascribed to the expansibility of a polyoxetane network and the hydrophilicity of the pendant acids.