Ferrocene polymers poly

The works of French scientists demonstrate considerable potential in the study of the chemieal aspects of ignition. It has been shown in Ref. that the addition of ferrocene to poly(vinyl chloride) strongly affects the self-ignition behavior of the polymer. Various glow phenomena are then observed which usually do not... 

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. 

In some cases the polymer incorporates the mediator, producing a redox macromolecule, e.g., poly[(ferrocenyl)amidopropyl]pyrrole, ferrocene-modified poly(ethylene oxide), " and highly flexible ferrocene-modified silox-ane. These redox polymers have short chains and low molecular weights (< 20 kDa) they function as a special kind of diffusional mediators and do not alleviate the loss of a mediator to the bulk solution during amperometric detection. 

Using the above strategies many types of ferrocene polymers have been successfully prepared. Thus, vinylferrocene can be polymerized by a variety of ways which include radical, cationic or anionic initiators to afford poly (vinylferrocene) (see Eq. 8.12). 

The presence of at least one alkyl group on the cyclopentadienyl motif is required to induce solubility in these poly(ferrocenylene persulfide)s. These polymers show two reversible oxidations. This type of electrochemical behavior is fairly common in ferrocene polymers where the ferrocene units are separated by short spacers as will be pointed out in the next section. 

Another approach is based on the application of redox polders, e.g. osmium complex-modified poly(vinyl pyridine) (9-11) or ferrocene-modified poly(siloxanes) (12,13X crosslinked together with an enzyme on the top of the electrode. The electron transfer fi-om the active site of the polymer-entrapped enzyme to the electrode surfece occurs to a first polymer-bound mediator which has suflSdently approached the prosthetic group to attain a fast rate constant for the electron-tranrfer reaction. From this first mediator the redox equivalents are transported along the polymer chains by means of electron hopping between adjacent polymer-linked mediator molecules (Fig. 2). Extremely fast amperometric enzyme electrodes have been obtained with si ificantly decreased dependence fi-om the oxygen partial pressure. However, die redox polymer/enzyme/crosslinker mbcture has to applied either manually or by dipcoating procedures onto the electrode surface. 

In 1992, Brandt and Rauchfuss reported the synthesis of polyferrocenylene persulfides via ROP of and desulfurization of [3]-trithiaferrocenes. High MW linear and network poly(ferrocene persulfide)s were produced by reaction of the trithiaferrocenes with These disulfide-linked ferrocene polymers... 

In many classical thermoelectrochemical experiments in open cells, which are directed at modem substances or actual processes, transport properties were of interest [89-93]. In a comprehensive impedance study of a conducting polymer, poly(tetracyanoquinodimethane) (polyTCMQ), Inzelt determined fundamental constants like diffusion coefficient, double-layer capacity and other quantities of the semiconductor layer as a function of temperature [89], Reduction kinetics of buckminsterfullerene Ceo has been studied [90] diffusion coefficients of different systems have been determined [91-93], among them/) of ferrocene/ferricinium in acetonitrile [92] and of vanadium ions [93]. In the latter example, activation energy of diffusion was also of interest. 

J. Xu, Y. Xian, R. Peng, Y. Xian, Q. Ran, and L. Jin. 2009. Ferrocene clicked poly(3,4-ethylenedioxythiophene) conducting polymer Characterization, electrochemical and electrochromic properties. Electrochem Cotntnun 11(10) 1972-1975. 

Zuo F, Luo C, Ding X, Zheng Z, Cheng X, Peng Y (2008) Redox-responsive inclusion complexation between p-cyclodextrin and ferrocene-functionalized poly(N-isopropyla-crylamide) and its effect on the solution properties of this polymer. Supramol Chem 20 559-564... 

Functionalized conducting monomers can be deposited on electrode surfaces aiming for covalent attachment or entrapment of sensor components. Electrically conductive polymers (qv), eg, polypyrrole, polyaniline [25233-30-17, and polythiophene/23 2JJ-J4-j5y, can be formed at the anode by electrochemical polymerization. For integration of bioselective compounds or redox polymers into conductive polymers, functionalization of conductive polymer films, whether before or after polymerization, is essential. In Figure 7, a schematic representation of an amperomethc biosensor where the enzyme is covalendy bound to a functionalized conductive polymer, eg, P-amino (polypyrrole) or poly[A/-(4-aminophenyl)-2,2 -dithienyl]pyrrole, is shown. Entrapment of ferrocene-modified GOD within polypyrrole is shown in Figure 7. 

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