SUPERMOLECULAR STRUCTURES ON THE BASE OF BLOCK-COPOLYMERS OF ETHYLENE-OXIDE, PROPYLENE-OXIDE, AND CYCLODEXTRINS

We have studied an 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. On the base of X-ray data, differential calorimetry, pulsed H-1 NMR, and IR-spectroscopy, we proposed 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. Additional stabilization of structure of the complex is caused by formation of hydrogen bonds between OH-groups of cyclodextrin and poly(ethylene oxide) block of proxanol. A study of formation of complexes in monolayers at interface water-air indicates that a rigidity of polymer chain in the complex increases, and the structures are formed with the same stoichiometry as in the bulk of water phase.