Chinese Journal of Chemical Engineering, Vol.20, No.4, 784-792, 2012
Immobilization of beta-Cyclodextrin as Insoluble beta-Cyclodextrin Polymer and Its Catalytic Performance
Insoluble beta-cyclodextrin polymers were prepared from beta-cyclodextrin (beta-CD) using epichlorohydrin (EPI) as crosslinking agent under basic conditions. The polymers were characterized by Fourier Transform Infrared (FTIR), Thermogravimetry (TG), X-ray diffraction (XRD) and TG-FTIR. The results demonstrated that the polymerization between EPI and beta-CD indeed occurred, and a number of CD rings were interconnected to form a three-dimensional network. Moreover, different factors influencing the polymerization, e.g. molar ratio of EPI to beta-CD, the concentration of NaOH and reaction temperature, have been investigated. The polymer prepared under the optimal conditions (the molar ratio EPI: beta-CD of 44, the NaOH concentration 50% in mass, and the temperature at 65 degrees C) showed excellent thermal stability and insolubility in organic solvents or strong acid/base. In addition, the beta-cyclodextrin polymers also presented high catalytic activity for aqueous oxidation of benzyl alcohol with hypochlorite as oxidant.