Direct synthesis of bifunctional mesoporous organosilicas containing chelating groups in the framework and reactive functional groups in the channel pores

International audienceThis paper describes the direct synthesis of bifunctional organosilica containing chelating groups in the framework and reactive functional groups in the channel pores. These materials were obtained in one step by direct synthesis using co-condensation of a bridged organosilica with chelating properties, tetraethylorthosilicate (TEOS) and an organotrialkoxysilane ZSi(OR)3 with Z = cyanopropyl, mercaptopropyl, chloropropyl in the presence of a non-ionic triblock co-polymer (P123) as structure directing agent. Bridged organosilicas used in this study include: 1,4,8,11-tetrakis-(triethoxysilylpropyl)-1,4,8,11-tetraazacyclotetradecane and the corresponding copper II chloride complex. The influence of different parameters on the textural and structural characteristics of materials has been investigated (concentration of the triblock copolymer P123, cosurfactant, hydrothermal treatment). The materials have been characterized by 13C and 29Si NMR experiments, nitrogen gas adsorption, powder X-ray diffractrion (XRD) elemental analysis and thermogravimetric analysis (TGA). The ability of chelating groups for complexation-decomplexation reactions was also investigated