High-performance polymers sulfones

Recently, Dutta and Maiti [21] reported nitro displacement polymerization of the bisphenol dianion with the sulfone activated dinitro aromatic compounds. In addition, there have been recent reports of the development of functionalized PEEK [22] and polyether sulfone ketone (PESK) [23] that are comparable to commercially available high performance polymers. 

Sulfonated poly(arylene ether)s have shown promise for durability in fuel cell systems, while poly-(styrene)- and poly(imide)-based systems serve as model systems for studying structure-relationship properties in PEMs because their questionable oxidative or hydrolytic stability limits their potential application in real fuel cell systems. Sulfonated high performance polymer backbones, such as poly(phe-nylquinoxaline), poly(phthalazinone ether ketone)s, polybenzimidazole, and other aromatic or heteroaromatic systems, have many of the advantages of poly-(imides) and poly(arylene ether sulfone)s and may offer another route to advanced PEMs. These high performance backbones would increase the hydrated Tg of PEMs while not being as hydrolytically sensitive as poly(imides). The synthetic schemes for these more exotic macromolecules are not as well-known, but the interest in novel PEMs will surely spur developments in this area. 

Colquhoum, H. M. Lewis, D. E Ben-Haida, A. Hodge, P. Ring-chain interconversion in high-performance polymer system. 2. Ring-opening polmerization-copolyetherification in the synthesis of aromatic poly(ether sulfones). Macromolecules 2003, 36, 3775-3778. 

Poly(p-phenylene sulfone) (PPSU) n. Chemically similar to the polysulfones, this high-performance polymer has better impact resistance. It also has excellent heat resistance, low creep and good electrical properties. It is difficult to process, however, which has limited its commercial acceptance. 

Yang L, Li H, Ai F et al (2013) A new method to prepare high performance fluorinated sulfonic acid ionomer4>orous expanded polytetrafluoroethylene composite membranes based on perfluorinated sulfo-nyl fluoride polymer solution. J Power Sources 243 392-3%... 

Blends of PEEK with other high performance polymers have also been reported for applications like fuel cells. Inan et al. [10] reported the blend of sulfonated PEEK with poly(vinylidene fluoride) (PVDF). Effect of the type and molecular weight of the flu-orinated polymer was investigated for low temperature fuel cell... 

Figure 2.8 Tensile properties of high performance polymers (SPODDPE, sulfonated polyoxadiazole PEEK, polyfether ether ketone) PES, poly(ether sulfone) Vespel , Poly(pjromellitimide-l,4-diphenyl ether) Torlon , poly(amide imide) Ultem , polyfether imide) LaRC, aromatic poly(imide) [34,35],...

Polyarylether sulfones are an important group of high performance polymers the first member, Bakelite polysulfone (Udel 50), may be made by condensation of a bisphenol (as the disodium salt, 51) with 4,4 -dichlorodiphenyl sulfone 52 (Equation 6). 

A promising alternative to the direct functionalization (sulfonation phospho-nation) of high performance polymers is offered by the chemical grafting... 

Table 3.1 shows continuous use temperatures for engineering and high performance polymers. For comparative purposes, 30% glass fibre-reinforced grades have been selected. PEEK has the highest continuous use temperature of up to 260 C, followed closely by liquid crystal polymers. Other high performance polymers are polyphthalamide (PPA), polyamideimide (PAI), polyarylimide, polyphenylene sulfone (PPSU), polyphenylene sulfide (PPS), polyetherimide (PEI), polysulfone (PSU), polyethersulfone (PES). 

Yin, Y., Chen, S., Guo, X., Fang, J., Tanaka, K., Kita, H., Okamoto, K.I. (2006) Structure-property relationship of polyimides derived from sulfonated diamine isomers. High Performance Polymers, 18, 617-635. 

Nakagawa, T., Nakabayashi, K., Higashihara, T., and Ueda, M. 2010. A high performance polymer electrolyte membrane based on sulfonated poly(ether sulfone) with binaphthyl units. / Mater. Chem. 20 6662-6667. 

An ultra class of high performing polymers (CUT > 240 °C) including polybenzimidazole (PBI), polyetheretherketone (PEEK), polyimide, polyamide-imide, polyether-imide (PI, PAI, PEI), high temperature sulfone (HTS), self-reinforced polyphenylene ether (SRP),etc. 

The aromatic sulfone polymers are a group of high performance plastics, many of which have relatively closely related stmctures and similar properties (see Polymers containing sulfur, polysulfones). Chemically, all are polyethersulfones, ie, they have both aryl ether (ArOAr) and aryl sulfone (ArS02Ar) linkages in the polymer backbone. The simplest polyethersulfone (5) consists of aromatic rings linked alternately by ether and sulfone groups. 

Solvent for Displacement Reactions. As the most polar of the common aprotic solvents, DMSO is a favored solvent for displacement reactions because of its high dielectric constant and because anions are less solvated in it (87). Rates for these reactions are sometimes a thousand times faster in DMSO than in alcohols. Suitable nucleophiles include acetyUde ion, alkoxide ion, hydroxide ion, azide ion, carbanions, carboxylate ions, cyanide ion, hahde ions, mercaptide ions, phenoxide ions, nitrite ions, and thiocyanate ions (31). Rates of displacement by amides or amines are also greater in DMSO than in alcohol or aqueous solutions. Dimethyl sulfoxide is used as the reaction solvent in the manufacture of high performance, polyaryl ether polymers by reaction of bis(4,4 -chlorophenyl) sulfone with the disodium salts of dihydroxyphenols, eg, bisphenol A or 4,4 -sulfonylbisphenol (88). These and related reactions are made more economical by efficient recycling of DMSO (89). Nucleophilic displacement of activated aromatic nitro groups with aryloxy anion in DMSO is a versatile and useful reaction for the synthesis of aromatic ethers and polyethers (90). 

Wholly aromatic polymers are thought to be one of the more promising routes to high performance PEMs because of their availability, processability, wide variety of chemical compositions, and anticipated stability in the fuel cell environment. Specifically, poly(arylene ether) materials such as poly-(arylene ether ether ketone) (PEEK), poly(arylene ether sulfone), and their derivatives are the focus of many investigations, and the synthesis of these materials has been widely reported.This family of copolymers is attractive for use in PEMs because of their well-known oxidative and hydrolytic stability under harsh conditions and because many different chemical structures, including partially fluorinated materials, are possible, as shown in Figure 8. Introduction of active proton exchange sites to poly-(arylene ether) s has been accomplished by both a polymer postmodification approach and direct co-... 

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