Surface Selectivity Competition of Newly Synthesized Polyarylidene(keto amine) Polymers Toward Different Metal Ions

A new series of polyarylidene(keto amine)s (PAKAs) 3(a)-3(e) based on thiophene moieties in polymer main chains were synthesized with the solution polycondensation technique. The polymers were synthesized by the reaction of the new monomer 1,10( 1E, 1'E)-(2-oxocyclohexane-1,3-diylidene)bis(methanylylidene)bis(thiophene-5,2-diyl)bis(2-chloroethanone) (2) with different diamines. The new monomer was first synthesized under the normal conditions of the Friedel-Crafts reaction. The results obtained from both elemental and spectral analyses were consistent with the chemical structure of the new monomers and the polymers. Moreover, the identification of the polymers was carried out with different characterization techniques. The analytical competition of the newly synthesized PAKA polymers as selected examples (3(d) and 3(e)) was also evaluated for a selective extraction of metal ions, including Cd(II), Co(II), Cu(II), Cr(III), Fe(III), Ni(II), and Zn(II), before their determination by inductively coupled plasma-optical emission spectrometry. The results of the selectivity study demonstrated that the 3(d) and 3(e) polymers was the most selective toward Co(II) and Fe(III), respectively. However, the adsorption capacity of 3(d) for Co(II) was improved by 10.10% in comparison to that of 3(e) for Fe(III) after only 1 h of contact time. Moreover, the adsorption isotherm data also showed that the adsorption process was mainly monolayer on the homogeneous adsorbent surfaces of both polymers. (C) 2014 Wiley Periodicals, Inc.