Poly- + FeCl

Molecular weights of poly(propylene oxide) polymers of greater than 100,000 are prepared from catalysts containing FeCl (40,41). The molecular weight of these polymers is gready increased by the addition of small amounts of organic isocyanates (42). Homopolymers of propylene oxide are also prepared by catalysis using diethylzinc—water (43), diphenylzinc—water (44), and trialkyl aluminum (45,46) systems. 

M TBAP in methylene chloride. After six hours controlled potential oxidation at 1.2 V, the blue color of filter paper on the side facing the anode turned to reddish brown. Complete oxidation of Poly B-411 in aqueous solution by TDCSPP FeCl and mCPBA gave the same color. The filter paper was not decolorized in a control experiment lacking veratryl alcohol. As Poly B-411 was not able to make direct contact with the electrode (since... 

Suspensions of polypyrrole were prepared by the FeCls oxidation of pyrrole in an aqueous solution of methylcellulose (49). The product was dried and yielded films with conductivities of 0.2 S/cm. Scanning electron microscopy revealed globular polypyrrole embedded in the methylcellulose matrix. After several months, these suspensions remained stable with no detectable precipitation. Similarly, the electropolymerization of 3-methyl-thiophene in solutions of poly(methyl methacrylate) and poly(vinyl chloride) was reported (50, 51). 

In relation to enzymic cytochrome P-450 oxidations, catalysis by iron porphyrins has inspired many recent studies. The use of CgFslO as oxidant and Fe(TDCPP)Cl as catalyst has resulted in a major improvement in both the yields and the turnover numbers of the epoxidation of alkenes. The Michaelis-Menten kinetic rate, the higher reactivity of alkyl-substituted alkenes compared to that of aryl-substituted alkenes, and the strong inhibition by norbornene in competitive epoxidations suggested that the mechanism shown in Scheme 13 is heterolytic and presumably involves the reversible formation of a four-mernbered Fe -oxametallacyclobutane intermediate. Picket-fence porphyrin (TPiVPP)FeCl-imidazole, O2 and [H2+colloidal Pt supported on poly(vinylpyrrolidone)] act as an artificial P-450 system in the epoxidation of alkenes. ... 

Polymeric tubes for clad lead-acid battery plates have been made from intrinsically conductive polymers [19] by weaving fibres of polypyrrole, poly(phenylene vinylene), or polythiophene of several hundred microns in thickness. Polyaniline [20] as well as polypyrrole, polyparaphenylene, and polyacetylene doped with anions (C104, FeCl, AsFj, sol", and HSO4) have also been added as 1.15pm powders or fibres to positive pastes to improve capacity [21]. 

Three groups of poly(3-alkylthiophene) have also been studied. The comparison of results between poly(3-octylthiophene) (POT) and poly(3-butylthio-phene) synthesised by FeCls oxidation (PBT(FeCl3)) will reveal the consequence of an increasing length of the alkyl chain on the substituted thiophene monomer. 

The first synthesis of a soluble and processible poly(2,7-fluorene) was reported by Yoshino and coworkers in 1989 [44,45]. Their approach involved coupling fluorene monomers with substituents at the C9 position by chemical oxidation with FeCls (see P3 in Scheme 1.2). However, the polymerization process was not regiospecific and the polymer backbone contained structural defects that influence the electronic delocalization. Thus, the synthesis of defect-free poly(fluorene)s became a major challenge and advances in carbon-carbon bond forming reactions promoted by organometallic catalysts provided the... 

Nanocomposites based on aluminum oxide, poly(pyrrole) (PPY), and PVK can be prepared by precipitating PVK in a suspension of PPY-coated aluminum oxide particles.A PPY/AI2O3 composite is added to an aqueous slurry of aluminum oxide powder, p5nrole, and anhydrous FeCls. 

The actual formation of hyperbranched material proceeds during the polymerization of 3,5-difluoro-4 -hydroxydiphenyl sulfone in the presence of 3,4,5-trifluorophenylsulfonyl benzene or tris(3,4,5-trifluorophenyl)phos-phine oxide as a core molecule. Cyclic oUgomers formed dining this polymerization contribute to a low-molecular-weight polymer ranging from 3400 to 8400 Dalton. A triazin-based AB2 monomer has also been described. This monomer is shown in Figure 7.8. A hyperbranched aromatic poly(ether sulfone) with sulfonyl chloride terminal groups has been prepared by the polycondensation of 4,4 -(m-phenylenedioxy)-bis-(benz-enesulfonyl chloride). The polymerization was carried out in nitrobenzene at 120°C for 3 h in the presence of a catalytic amount of FeCls. ... 

Fig. 3. Room temperature electrical conductivity of FeCl doped poly(p phenylene) as a function of the wt % Fe...

A number of studies on the related polymer, poly (thieno[3,4-fo]pyrazine) (2), and its derivatives have also been reported since the second edition of this handbook. The first example of a poly(thieno[3,4-b] pyrazine) was reported by Pomerantz and coworkers [16,17] in 1992 with the FeCls polymerization of 2,3-dihexylthieno[3,4-l ]pyrazine to give 2c (Scheme 12.7) exhibiting an g of 0.95 + 0.10 eV. 

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