zinc ions have been coordinated with non-bonding electron pairs
of nitrogen in N–H and C55N groups in diphenylcarbazone, and as a
result, it demonstrates the presence of zinc ions in unleached IIP
structure. Moreover, the presence of C55N and N–H bands in the IR
spectra of these materials indicated that diphenylcarbazone had
been sufficiently immobilized in the polymer matrix. Thermal
stability of the leached and unleached polymer particles was
evaluated by thermo gravimetric analysis. Fig. 2 shows that TGA
and DTA plots for (a) unleached and (b) leached ion imprinted
polymer. In DTA plots of zinc imprinted polymer, exothermic peaks
were observed at 352.2, 494.9, and 567.3 (for unleached) and
239.6, 343.2, 478.4 and 565.8 8C (for leached). As it is shown in TG
plots for ion imprinted particles, weight loss for Zn(II)-IIP was
about 97%, and this amount of reduction in weight was related to
the presence of Zn(II) ions in polymer bead. While decrease in
weight for leached imprinted polymer up to 100%, is due to
absence of zinc ions in polymer. These observations indicate that
the formation of Zn(II)-imprinted polymer and elution of Zn(II)
ions from the polymer was performed successfully. The morphology
of the Zn(II)-IIP was assessed by SEM, and the patterns are
shown in Fig. 3. The XRD patterns of the leached (a) and unleached
(b) IIP particles are shown in Fig. 4. The XRD patterns of the leached
(a) and unleached (b) IIP particles indicated different patterns. In
unleached IIP, peaks related to zinc can be seen while these peaks
were absent in the curve of leached IIP. In order to further examine
the porous structure of the synthesized imprinted polymer, N2
adsorption-desorption isotherms were employed. The surface
area, pore volume and mean pore size of the sorbent determined by
BET method were about 7.3 m2 g1, 0.15 cm3 g1 and 8.23 nm,
respectively