Metal oxide-induced grafting

Metal Oxide-Induced Grafting of Methyl Acrylate on Fibers... 

The exploitation of oxidation or reduction reactions occurring oti the surface of a polarized electrode [24, 27] can lead to the formation of a variety of monolayers depending on the nature of the organic species. As an example, amines, alcohols, and carboxylic acids can be anchored to metal and C-based surfaces through anodic oxidations similarly, cathodic reductions can induce grafting of vinyl moieties. 

In recent studies, clusters of ions such as copper or iron and their oxide were deposited (grafted) to induce photoexcitation of electrons in VB of base metal oxide such as titania to the electronic level... 

The most widely used method for chemical initiation for graft copolymerization on polysaccharides has been with ceric salts such as CAN or ceric ammonium sulfate. Free radical sites are generated on a polymeric backbone by direct oxidation through ceric metal ions (e.g., Ce "). The ceric ion with low oxidation potential is the proper choice for the reaction. The proposed mechanism for such processes has been depicted by an intermediate formation of metal ion polymer complex (chelate type) [17, 21-24]. Such a complex formation is not restricted to all polymers. The plausible mechanism for ceric ion induced graft copolymerization by direct oxidation method is shown in Scheme 3.1. A series of four grades of Ag-g-PAM copolymers have been synthesized by the conventional method. 

A special case of "grafting from" reaction is the chemical modification that can be induced on a metalated backbone chain by micromolecular reagents. A recent example of such reactions is the oxidation of metalated sites on a polystyrene chain, yielding vinylphenol units. It has been shown that in this case metalation (using BuLi, TMEDA) is located on the phenyl rings. 

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