Sulfonated hyperbranched

Figure 2.14 Self-doped mechanism of hyperbranched sulfonated polydipheny-lamine. (Reprinted with permission from Macromolecules 38, 888. Copyright (2005) American Chemical Society.)...

F. J. Hua, E. Ruckenstein, Hyperbranched sulfonated polydiphenylamine as a novel self-doped conducting polymer and its pH response, Macromolecules 2005, 38, 888. 

Fig. 25 Synthetic route towards a hyperbranched sulfonated poly(ether sulfone)...

Although low-molar-mass aliphatic polyesters and unsaturated polyesters can be synthesized without added catalyst (see Sections 2.4.1.1.1 and 2.4.2.1), the presence of a catalyst is generally required for the preparation of high-molar-mass polyesters. Strong acids are very efficient polyesterification catalysts but also catalyze a number of side reactions at elevated temperature (>160°C), leading to polymers of inferior quality. Acid catalysts are, therefore, not much used. An exception is the bulk synthesis of hyperbranched polyesters reported in Section 2.4.5.1, which is carried out at moderate temperature (140°C) under vacuum in the presence of p-toluene sulfonic acid catalyst. The use of strongly acidic oil-soluble catalysts has also been reported for the low-temperature synthesis of polyester oligomers in water-in-oil emulsions.216... 

Frey and Van Koten et al. [40-42] reported on the noncovalent encapsulation of sulfonated pincer-platinum(II) complexes in readily available amphiphilic nanocapsules based on hyperbranched polyglycerol, possessing a reverse micelle-type architecture. The incorporated platinum(II) complexes showed catalytic activity in a double Michael addition, albeit with decreased activities compared to the free pincer complex. Due to the size of... 

A hyperbranched polymer 47 containing Re(bipyridine)(CO)3Cl chromophores (the Re(CO)3Cl+ moiety is denoted as [Re]) linked by bipyridineethylene bridges was deposited with a sulfonated polythiophene to yield a solar energy conversion material. This displayed open-circuit voltages of 1.2 V and photocurrents of 27 iA cm 2 under solar illumination [94]. 

In general, hyperbranched polymers are obtained by the polymerization of an AB2 monomer. Thus, in the first step, the hyperbranched PES must be manufactured. For example, the synthesis of 3,5-difluoro-4 -hydroxydi-phenyl sulfone can be accomplished by the reaction of 3,5-difluorophenyl-magnesium bromide with 4-methoxyphenylsulfonyl chloride, followed by deprotection of the phenol group with HBr in acetic acid." ... 

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. ... 

P. Himmelberg and E. Possum. Development of an efficient route to hyperbranched poly(arylene ether sulfone)s. J. Polym. ScL, Part A Polym. Chem., 43 3178-3187,2005. 

Y. Chang, Y. C. Kwon, K. Paik, and C. Kim. Hyperbranched poly(ether sulfone) with 1,3,5-i-triazine moiety. Korea Polym. J., 8 142-146,2000. 

K. Matsumoto and M. Ueda. Synthesis of hyperbranched aromatic poly-(ether sulfone) with sulfonyl chloride terminal groups. Chem. Lett., 35 1196-1197,2006. 

Catalytic production of levulinic acid from cellulose and other biomass-dtaived carbohydrates with sulfonated hyperbranched poly(arylene oxindole)s. Energ Environ Sci 4(9) 3601-3610... 

Van de Vyver S, Thomas J, Geboers J, Keyzer S, Smet M, Dehaen W, Jacobs PA, Sels BF (2011) Catalytic production of levulinic acid from cellulose and other biomass-derived carbohydrates with sulfonated hyperbranched poly(arylene oxindole)s. Eneigy Environ Sci 4(9) 3601-3610... 

Sulfonated hyperbranched PEEK was synthesized by the sulfonation of fluoro-terminated hyperbranched poly(aryl ether ketone) [86], These materials were used in combination with sulfonated linear PEEK for proton exchange membranes. 

Matsumoto K, Ueda M. Synthesis of hyperbranched aromahc poly(ether sulfone) with... 

A variety of high-temperature-resistant PBIs were synthesized and reported in the Uterature. The most widely used PBI is poly[2,2 -(l,3-phenylene)-5,5-benzimidazole] (known as m-PBI) [22]. The other variations are poly[2,2 -( 1,4- phenylene)-5,5 -benzimidazole] (known as p-PBI) [13], poly(4,4 -diphenylether-5,5 -bibenzimidazole) (OPBI) [23], poly(2,5-benzimidazole) (AB-PBI) [24], pyridine-based PBI [25], sulfonated PBI [26], hyperbranched polybenzimidazole (HPBI) [27], naphthalene-based PBI [28], fluorinated PBI [29], PBI block copolymer [30], sulfonated PBI copolymer with sulfone or sulfonic acid groups in the backbone [31,32], PBFnano-composite [33], cross-linked PBI [34], and many others. Different approaches have been taken by the researchers to modify the structure and properties of the fluorinated PBI. A detailed summary of these works is discussed below. 

T. Suda, K. Yamazaki, H. Kawakami, Syntheses of sulfonated star-hyperbranched poly-imides and their proton exchange membrane properties, J. Power Sources 195 (15) (2010) 4641-4646. 

Das, G., Kalita, R.D., Deka, H., Buragohain, A.K., Karak, N., 2013. Biodegradation, c)4o-compatability and performance studies of vegetable oil based hyperbranched pol3mrethane modified biocompatible sulfonated epoxy resin/clay nanocomposites. Progress in Organic Coatings 76, 1103-1111. 

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