Poly arylene Ether Sulfone s

Poly(arylene ether sulfone)s (PAES)s have been known since the 1970 s. They are tough linear polymers and possess a number of attractive features, such as excellent high-temperature resistance, good electrical properties, and good hydrolytic stability. The topic has been reviewed previously in the hterature.  

In this text, we prefer the term arylene ether over aryl ether, in the sense that the aryl group is situated in the backbone of the polymer for example, recall the meaning of the term methylene. There are variants of this t) e of polymer, for example, poly(ether ketone sulfone)s, or poly(ether ether ketone sulfone)s. Basically, a poly(ether ketone sulfone) can be understood as a copol5mier bearing both the poly(ether ketone) moiety, and the poly(ether ketone) moiety in the backbone. This type of polymer could be dealt with either in the poly(ether ketone) chapter or in this chapter it is a matter of taste that we include this type here. Still other variants are summarized in Table 7.1. 

The nomenclature is not unique. Sometimes, PAESs are simply addressed as poly(sulfone) resins. When collecting the literature to this text, more then 100 acronyms referring to polymers that containing sulfone groups were encountered. A few acronyms are compiled in Table 7.1. 

In ordinary organic chemistry, thioether is a synonym for sulfide. A thioether or sulfide is a compound that contains the R—S—R link. This is in contrast to the nomenclature of polymer chemistry. A polysulfide is a polymer that contains the —S—S— group in the backbone. However, a poly (sulfide), with sulfide in brackets, such as poly(phenylene sulfide) or 

Poly(arylene thioether ketone ketone sulfone) PATKKS 

The incorporation of SO2 groups into the main chain of poly(phenylene ether)s leads to poly(phenylene ether sulfone)s. The preferential synthetic routes are  

The nucleophilic polycondensation has the advantage that the chemical structure and thus the properties of the poly(ether sulfone)s can be varied in a relatively simple way through the selection of the bisphenol components. 

The technically most important poly(arylene ether sulfone) is obtained from bisphenol A and 4,4 -dichlorodiphenyl sulfone by nucleophilic aromatic polysubstitution. 

The reaction is carried out in dimethyl sulfoxide at 130-160°C under an inert atmosphere. High purity of the starting materials is of prime importance in order to obtain high molecular weights. The water, which results from the neutralization of the bisphenols, can be removed via an azeotropic distillation with toluene. 

Because of the angled structure of poly(arylene ether sulfone)s, they generally do not crystallize. They are thus amorphous and optically transparent with glass transition temperatures between 150-200°C. They are soluble in some polar solvents, hydrolysis resistant, and inherently flame resistant. Fields of application for these materials are foxmd particularly in the area of electronics and membrane technology. 

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The general approaches for the synthesis of poly(arylene ether)s include electrophilic aromatic substitution, nucleophilic aromatic substitution, and metal-catalyzed coupling reactions. Poly(arylene ether sulfone)s and poly(arylene ether ketone)s have quite similar structures and properties, and the synthesis approaches are quite similar in many respects. However, most of the poly(arylene ether sul-fone)s are amorphous while some of the poly(arylene ether)s are semicrystalline, which requires different reaction conditions and approaches to the synthesis of these two polymer families in many cases. In the following sections, the methods for the synthesis of these two families will be reviewed. 

Poly(arylene ether sulfone)s can be synthesized by two different polysulfonyla-tion reaction routes condensation of AA and BB monomers or self-condensation of AB monomer.26,27 Scheme 6.5 shows two approaches. 

Sulfonic acid catalysts can also be used to prepare poly(arylene ether sulfone)s, such as (CF3C0)20, polyphosphoric acid (PPA),26 MeS03H-P205 mixture,33 and CF3SO3H.34... 

Scheme 6.13 Synthesis of poly(arylene ether sulfone)s via silyl ether displacement.

Polyether-PA segmented copolymers, synthesizing, 191-192 Polyether polyols, 200, 205, 211-212 synthesis of, 223, 224 Poly(ether sulfone) (PES), 327. See also Poly(arylene ether sulfone)s Poly(phenylene ether sulfone) chains Sulfonated poly (ary lene ether sulfone)... 

Schonberger, R, Hein, M. and Kerres, J. 2007. Preparation and characterization of sulfonated partially fluorinated statistical poly(arylene ether sulfone)s and their blends with PBl. Solid State Ionics 178 547-554. 

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. 

The chemical modification of poly(arylene ether sulfone)s has already been described in numerous papers. They relate to sulfonation, fluorination, and halomethylation. These derivatives are particularly suitable for the preparation of hydrolysis- and temperature-resistant separation membranes. They are used already for sea water desalination, and also for the separation of gas mixtures. 

The synthesis of poly(arylene ether sulfone)s with other bisphenols, e.g., 4,4-bis(4-hy-droxyphenyl)pentanoic acid, can be carried out in a similar way. 

In analogy to poly(arylene ether sulfone)s, there are two different polycondensation methods for the technical synthesis of poly(arylene ether ke-tone)s ... 

Lyle G, Hedrick JC, Lewis DA, Senger JS, Chen DH, Wu SD, McGrath JE (1989) Synthesis and characterization of maleimide terminated poly(arylene ether sulfone)s. In Feger C, Khojasteh MM, McGrath JE (eds) Polyimides materials, chemistry and characterization. Elsevier, Amsterdam, p 213... 

The incorporation of engineering thermoplastics, such as poly(arylene ether sulfone)s, polysulfone. 

Figure 10.7 Structures of sulfonated poly(arylene ether sulfone)s possess different sulfonic acid positions.

Poly(arylene ether sulfone)s 271 Table 7.7 Tradenames in References... 

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. 

H. A. Every, M. A. Hickner, J. E. McGrath, and T. A. Zawodzinski, Jr. Nafion versus sulfonated poly(arylene ether sulfone)s. A comparison of the methanol diffusion behavior. In Fuel Cells from Materials to Systems, The Electrochemical Society, Pennington, New Jersey 08534-2839, USA, 2003. 203rd Meeting of the The Electrochemical Society, Paris. 

J.-W. Kang, J.-P. Kim, J.-S. Lee, and J.-J. Kim. Structure-property relationship of fluorinated co-poly(arylene ether sulflde)s and co-poly(arylene ether sulfone)s for low-loss and low-birefringence waveguide devices. J. Lightwave Tech., 23 364-373, 2005. 

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