New Strategy for the Synthesis of Diethylenetriaminetetraacetic Acid Functionalized Polysiloxane Ligand Systems

Abstract

A new rout was used for the synthesis of porous solid polysiloxane matrix of the general formula P-(CH₂)₃N(CH₂COOEt)-(CH₂)₂N(CH₂COOEt)-(CH₂)₂-N(CH₂COOEt)₂ (where P represents [Si-O]_n) by the reaction of diethylenetriaminetrimethoxysilane with ethyl chloroacetate followed by polymerization with tetraethylorthosilicate via the sol gel process. The functionalized diethylenetriaminetetraacetic acid polysiloxane system (P-DETATA) was then obtained by acid hydrolysis of the diethylenetriaminetetraethylacetate functionalized polysiloxane(P-DETATAc). FTIR, ¹³C, ²⁹Si CP-MAS NMR and XPS methods were used for characterization of their chemical structure. The new functionalized ligand system exhibits high capacity to coordinate with divalent metal ions (Co²⁺, Ni²⁺, and Cu²⁺) than its analogous ligand obtained by postmodification of triamine polysiloxane with ethyl chloroacetate.

Keywords:

• Chelating ligands
• diethylenetriamine
• immobilized-polysiloxane ligand systems
• metal uptake
• metal uptake
• polysiloxanes
• preconcentration of metal ions

Notes

^a Analyses results of the esters based on complete reactions, while that of acids based on the found results of the esters precursors.