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ملخص البحث |
The polysiloxane-immobilized thiol, amine, and thiol-amine ligand systems P-(CH2)3X (where P represents the siloxane network, X=SH,NH2 , or hybride of amine and thiol ligand groups) have been made via the sol-gel process by hydrolytic condensation of Si(OEt)4 and (MeO)3Si(CH2)3X. The immobilized polysiloxanes thiol-acetate P-(CH2)3SCH2COOMe and glycinate P-(CH2)3NHCH2COOMe have been prepared by the reaction of P-(CH2)3SH, P-(CH2)3NH2 with methylchloroacetate. The immobilized thiol-amine ligands form metal(II) complexes when treated with aqueous metal(II) ion solutions (M=Ni2+,Cu2+,Cd2+, Hg2+). High resolution solid state NMR studies have been used to characterise these immobilized ligand systems and their metal(II) treated samples. 29Si CP-NMR spectra suggest that these ligand systems undergo some leaching(1-4%) of small oligomers when treated with aqueous acid and metal ion solutions. 15N CP-NMR results show that substantial proportion of amine groups are coordinated to metal ions. |
