The resol polycondensation of C-phenylcalix{4]resorcinarene with formaldehyde affords a cross-linked polymer possessing ion-exchange ability. The ion-exchange capacity of the polymer with respect to NH4 +, Me4 N~', Et4N*. Bu4N ~', and K + cations was determined. The equilibrium in the systems C-phenylcalix[4lresorcinarene-based polymer--binary or ternary aqueous solutions of electrolytes was studied by potentiometric titration and quantumchemical MN DO/PM3 calculation.Key words: C-phenylcalix[4[resoreinarene, polymer, quaternary, ammonium bases, potassium hydroxide, ion exchange, potentiometric titration, quantum-chemical calculation. MNDO/PM3 method.Calixarenes possess unique biomimetic properties, t We have shown z that the tetramethylcalix[4]resorcinarene-based polymer can enter an ion-exchange reaction. In this work, we studied the equilibria in the systems C-phenylcalix[4]resorcinarene-based polymer--binary or ternary aqueous solutions of NH4*, Me4N +, Et4N § Bu4N-, and K + hydroxides and chlorides.The resol polycondensation of C-phenylcalix[41resor-cinarene (I) with formaldehyde affords the cross-linked polymer (2) (Scheme I).Polymer 2 can enter into the exchange reaction between the protons of the OH groups and cations of a solution. Due to substantial differences in the ionization constants of the OH groups of resorcinol (pKal = 9.15, PKa2 = 11.33), 3 four protons of the elementary unit of polymeric molecule 2 (one proton per resorcinol fragment) can be expected to participate in the cation exchange. The ion-exchange reaction is described by the equation Here the line above the symbol designates belonging to the polymeric phase; Cat ~ is the sorbed cation; and n is an integer, n ~ 4. resorcinarene was prepared by the condensation of resorcinol with benzaldehyde. 4 To identify 1, its acetate was synthesized. 5 The melting points and IR spectra of 1 and its acetate were in correspondence with the published data.4. 5
ExperimentalThe polymer was obtained as spherical granules with an average diameter of 0.25 mm by the catalytic resol polycondenPublished in
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