Supermolecular structures based on poly(ethylene oxide)-poly(propylene oxide) block copolymers and cyclodextrins

The interaction of block copolymers of ethylene oxide and propylene oxide (proxanols and pluronics) of different types with cyclodextrins, which leads to formation of crystalline, insoluble and soluble in water complexes, was studied. On the basis of X-ray data, differential calorimetry, pulsed 1 H NMR, and IR spectroscopy, a model of crystalline complexes where molecules of cyclodextrin are arranged along poly(propylene oxide) block of proxanol with one molecule of cyclodextrin per two units of propylene oxide was proposed. Additional stabilization of the structure of the complex is caused by formation of hydrogen bonds between OH groups of cyclodextrin and poly(ethylene oxide) block of proxanol