Synthesis and characterization of 1,4,8,11-tetraazacyclotetradecane carrying poly(p-chloromethyl styrene-ethylene glycol dimethacrylate) microbeads and its metal ion-chelated forms

Poly(p-chloromethyl styrene-ethylene glycol dimethacrylate) polymeric microbeads, poly(p-CMS-EGDMA), with an average size of 186 μm were synthesized by the suspension polymerization of p-CMS conducted in an aqueous medium. To increase the rigidity of the polymeric microbeads, EGDMA monomer was added to polymerization medium in the 25% for the cross-linking. 1,4,8,11-Tetraazacyclotetradecane ligand was reacted with polymer active groups that was p-CMS under a nitrogen atmosphere for 18 h at 65 °C. The maximum cyclam attachment was found 2.24 mmol/g polymer using an elemental analyser. Fourier transform infrared (FT-IR) spectrophotometer, thermogravimetric analyser (TGA) and differential scanning calorimeter (DSC) were used to characterize the plain, ligand modified microbeads and metal ion-chelated microbeads. TGA and DSC characterization of modified microbeads showed that stability of cyclam was increased attaching onto the polymer and metal ion-chelated form of the cyclam-modified polymer were more stable at high temperature for different applications.