Synthese und anwendung polymerer redoxsysteme

Abstract

In dieser Übersicht werden die Synthesemöglichkeiten für Polymere, die reversible organische Redoxsysteme enthalten, beschrieben. An ausgewählten Beispielen werden ihre Eigenschaften erlätert. Zur Deutung des elektrochemischen Verhaltens werden molekulareinheitliche niedermolekulare Modellverbindungen herangezogen. Die polymeren Redoxsysteme lassen sich als unlösliche regenerierbare Reduktions‐ bzw. Oxydationsmittel einsetzen. This review describes various possibilities of synthesizing polymers having incorporated reversible organic redox systems. The properties of these polymers are discussed for selected examples. Low and uniform molecular weight model compounds were synthesized in order to study the electrochemical properties. The redox resins can be employed as insoluble regenerative oxidation and reduction agents.

Electron‐transfer polymers (oxidation‐reduction polymers)

“…LXXI t LXXIII 2 LXXII ( 5 ) It is evident from Table IV that when the connecting bridge contains about five or more consecutive -CH2units the redox groups behave by this titration criterion as though effectively isolated from each other. Manecke's results are in essential agreement (5,148,150).…”

“…As in the case with any contacting of reagents one may employ batchwise, co-current, or countercurrent procedures. Redox polymers may be used in these ways (1,5). The most efficient procedure, where it is applicable, is the differential countercurrent contacting that is a feature of all chromatographic processes (32,33).…”

“…Redox polymer in the oxidized form has been shown to dehydrogenate hydrogenated aromatic substances especially where increased resonance stabilization can drive the reaction (1,5,154). Steric factors are important also.…”

“…Oxygen of the air then reoxidizes it to the quinone form. Studies of the type of reaction have been made by Manecke and his colleagues (5,152), and for example, alanine yielded acetaldehyde and leucine isovaleraldehyde.…”

Organic redox polymers as electrochemical energy materials

“…An organic redox polymer for hydrogen transport and storage clearly needs to be identified as a green means of supplying and storing on-site hydrogen. 31 The electrochemical redox production of hydrogen peroxide, hydrogen, and oxygen are sustainable chemistry pinnacles, and significant effort has focused on producing: (1) hydrogen peroxide by the reduction of oxygen in water; and (2) hydrogen and oxygen by the reduction and oxidation of water. 32,33 While ( photo)(electro)chemical redox catalysis methods have been extensively developed using metals, metal oxides, and carbon materials, [34][35][36][37][38] those using redox processes at the polymer film interface with water are now emerging, driven by organic-polymer molecular engineering, from the perspectives of both redox potential and the hydrophilic, large surface area of the reaction interface with water, in addition to the benefits of chemical robustness in acidic/alkaline water and byproducts that do not require separation.…”