1997 Fiscal Year Final Research Report Summary
On the Mechanisms of Ionic Reactions at the Highly Charged Interface
| Project/Area Number |
08454237
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
分離・精製・検出法
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| Research Institution | KYUSHU UNIVERSITY |
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Principal Investigator |
MIYAJIMA Tohru Kyushu University, Faculty of Science, Department of Chemistry, Associate Professor, 理学部, 助教授 (40128103)
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| Co-Investigator(Kenkyū-buntansha) |
ISHIGURO Shin-ichi Kyushu University, Faculty of Science, Department of Chemistry, Professor, 理学部, 教授 (80111673)
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| Project Period (FY) |
1996 – 1997
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| Keywords | Polyelectrolytes / Ion-Exchange / Complexation equilibria / Hydrophobicity / Hydrophilicity |
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| Research Abstract |
Any ionic reactions of charged macromolecules (linear-, cross-linked linear polymers, and ionic micelles, etc.) , whether they are positively or negatively charged, can be analyzed by assuming a two-phase property of polyion/supporting electrolyte systems. In this reserch project, novel analytical treatments of the equilibria of ionic reactions in polyion systems have been examined. Acid-dissociation and metal complexation properties of weakly acidic polyelectrolytes (polyacrylic acid and polymethacrylic acid) and the conjugate acids of weakly besic polyelectrolytes (poly (N-vinylimidazole) and polyallylamine) , have been analyzed in a unified manner. High sensitivity of the equilibria to the added salt concentration levels was interpreted by a Donnan-based concept. By the use of the non-ideality terms of the acid-dissociation equilibria of the polyacids, the electrostatic effect on the metal complexation equilibria of the charged polymer systems has been evaluated correctly, which made possible to extract the intrinsic formation constants of the metal complexes formed at the polymer surface. This "phase-separation" concept in polyion systems has also been applied to the quantification of "polyelectrolyte eatalysis" . Acceleration of Fe^<2+>/ [Co (NH_3) _5Cl] ^<2+> electron transfer reaction with the addition of strongly acidic polyions, polyvinylsulfonate ions, has been examined. Polyelectrolyte phase volume needed to interpret the reaction acceleration was consistent with the value calculated by the use of counterion binding equilibrium data. Pronounced hydrophobic interaction between counterions and charged polymer sites has been revealed for small anion-positively charged polymer systems. Complexation behavior of Co^<2+>/SCN^- in the presence of polyvinylbenzyltrimethylammonium ions has been investigated. It has been indicated that the hydrophobic interaction is greatly affected by the hydrophobic nature of supporting anions.
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Research Products
(12 results)
