Synthesis and properties of water-insoluble β-cyclodextrin polymer crosslinked by citric acid with PEG-400 as modifier

Water-insoluble β-cyclodextrin polymer (β-CDP) crosslinked by citric acid was synthesized with Polyethylene glycol 400 (PEG-400) as modifier through an environment friendly procedure. The yield of β-CDP was related to the amounts of citric acid, PEG-400 and catalyst in the formulation. β-CD content and total acidic groups of the produced β-CDP were also found to be related to the formulation. FT-IR spectra disclosed that the hydroxyl groups of β-CD had crosslinked with the carboxyl groups of citric acid, and at the same time the structure characteristics of β-CD were well maintained in the polymer. Preliminary study on adsorption toward aniline disclosed that β-CDP which had a larger amount of total acidic groups generally had a larger adsorption capacity towards aniline.