Catalysts, ferrocene-based polymers

Copolymerization reactions with ferrocenophanes using transition metal catalysts have also been accomplished. The self-assembly of block copolymers has been examined, and polymers with dimethylsiloxane or ethyleneoxide blocks have been found to be soluble in aqueous solution. These ferrocene-based polymers have been found to self-assemble in solution, and their morphologies have been investigated. A number of water-soluble anionic (26) and cationic (27) polyelectrolytes have also been produced by sidechain functionalization. 

The polymerization of ferrocene derivatives set the stage for a new era in polymer chemistry. After the 1955 report by Arimoto and Haven describing the synthesis of polyferrocenylethylene" (Scheme 1), a number of researchers pursued the synthesis and characterization of ferrocene-based polymers. In addition to the radical-initiated polymerization of monomer 6, polymer 7 was also prepared using phosphoric acid or persulfate as catalysts. The copolymerization of vinylferrocene was examined with methyl methacrylate, styrene, and chloroprene. 

Ferrocene has been reported to be very effective as a soot reducing agent in combustion [42 — 44]. Thus, when ferrocene compounds are incorporated in a fire retardant polymer, such as a phenolphthalein-based polymer and poly(phosphate ester)s, they have shown added advantages in that they promote extinction and reduce smoke formation by accelerated char reduction [45, 46]. The synthesis of such ferrocene-containing poly(phosphate ester)s was achieved by interfacial polycondensation using a phase transfer catalyst [47]. Accordingly, l,l -bis(p-hydroxy-phenylamido)ferrocene and l,l -bis(p-hydroxyphenylcarbonyl)ferrocene underwent condensation with various aryl phosphoroic acid dichlorides to yield two series of ferrocene-containing polymers, i.e., poly (amide-phosphate ester)s 38a and poly(ester-phosphate ester)s 38b respectively, as shown in Scheme 10-17. 

A classical approach to improving the sensitivity of ECP-based sensors consists of the immobilization of catalytic moieties, such as metallic particles [136-142], Prussian blue [143], ferrocene [144], metalloporphyrins [145-148], and oxometalates [149-152], within ECP films. Compared to polymers without a catalyst, these materials exhibited more pronounced electrocatalytic effects and were suitable for the detection of numerous molecules of biological interest, e.g., carbohydrates [136, 141], catecholamines [144], and NO [145,150-152]. 

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