Emulsion reduction-oxidation catalysts

It was discovered that the addition of 1,3-cyclohexadiene to the Rh -catalyzed reactions increased the rate of butadiene polymerization by a factor of over 20 [20]. Considering the reducing properties of 1,3-cyclohexadiene, this effect could be due to the reduction of Rh to Rh and stabilization of this low oxidation state by the diene ligands. With neat 1,3-cyclohexadiene, Rh is reduced to the metallic state. These emulsion polymerizations are sensitive to the presence of Lewis basic functional groups. A stoichiometric amount of amine (based on Rh) is sufficient to inhibit polymerization completely. It was also discovered that styrene could be polymerized using the Rh catalyst. However, the atactic nature of the polymer, along with the kinetic behavior of the reaction, indicated that a free-radical process, rather than a coordination-insertion mechanism, was operative. 

Uses Chelating agent used in photographic developers, oxidation-reduction systems, and emulsion polymerization iron source micronutrient fertilizer trace element additive animal feeds polymerization catalyst for syn. rubber in food-pkg. adhesives Reguiatory FDA 21CFR 175.105 Trade Name Synonyms Dissolvine NAFE [Akzo Nobel http //www.akzonobel.com], Ferric Monosodium Detarate Powder [Hampshire http //www.dow.com/hampshire] Hamp-Ene NaFe Purified Grade [Hampshire http //www. dow. com/hampshire] ... 

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