SYNTHESIS AND ION BINDING-PROPERTIES OF EPOXY POLYMERS WITH DIAZACROWN ETHERS

The synthesis of polymers obtained by polycondensation of two macrocyclic diamines [21] and [22] (l, 4, 10-trioxa-7, 13-diazacyclopentadecane and 1, 7, 10, 16-tetraoxa-4, 13-diazacyclooctadecane) with the diglycidic ether of 2, 2-bis(4-hydroxyphenyl)propane (Epikote 815) is described. The polymers strongly chelate with cations, and their efficiency and selectivities in binding cations are compared with those of their monomeric analogues by using data obtained from water-chloroform extraction measurements. The stability constants for the polymeric complexes are comparable to those of the analogues whatever the ratio of complexation, indicating that the polymeric structure has no influence on the structure of the complexes. With all of the cations studied (alkali, alkaline earth, and Cu2+, Cd2+, and Pb2+), the stoichiometry 1:1 was observed in chloroform. With alkali and alkaline earth cations, the selectivity is governed by the respective size of the cations and of the internal cavity of the cycles. With Cu2+, Cd2+, and Pb2+ cations, higher stabilities are obtained with the larger cycle. Experiments with mixtures of cations indicate that complexation properties are additive. The stability constants obtained with picrate and perchlorate anions are very comparable, showing that both anions lead to complexes with comparable binding energies. These results, in addition to results obtained by UV spectroscopy, are interpreted in terms of interactions of the anions with the protons of the hydroxylic groups present near the cycles. Aging experiments with oxygen and carbon dioxide indicate that the binding properties are not affected by the aging of the polymers. © 1979, American Chemical Society. All rights reserved.