| Abstract
| - Thermodynamic analysis of inclusion complexation between α-cyclodextrin-based molecular tube (MT) andpoly(ethylene oxide)-block-poly(tetrahydrofuran)-block-poly(ethylene oxide) triblock copolymer (PEO-b-PTHF-b-PEO) was carried out in terms of isothermal titration calorimetry. As for the titration of MT to PEO inaqueous solution, no strong exothermic peak was observed. On the contrary, strong exothermic peaks wereobserved for the titration of MT to PEO-b-PTHF-b-PEO in aqueous solution, which is attributable to inclusioncomplexation between MT and the triblock copolymer. Thermodynamic parameters were obtained for theprocess of inclusion complexation between MT and PEO-b-PTHF-b-PEO by changing the molecular weightof MT and the temperature. The stoichiometry of inclusion complexation changes in relation to the molecularweight of MT. Interestingly, it was found that MT with a large molecular weight behaves as the host moleculehaving multibinding sites. Thermodynamic parameters suggested that van der Waals interaction, hydrophobicinteraction, and hydrogen bond play an important role to determine the magnitude of ΔH. Some thermodynamicparameters clearly indicated that the dehydration of the triblock copolymer is a key factor in inclusioncomplexation between MT and PEO-b-PTHF-b-PEO. These results afford a deeper insight into the mechanismof the macromolecular recognition process.
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