Polybenzimidazoles sulfonation

C. Hasiotis, L. Qingfeng, V Deimede, J.K. Kallitsis, C.G. Kontoyannis and N.J. Bjerrum, Development and characterization of acid doped polybenzimidazole/ sulfonated polysulfone bend polymer electrolytes for fuel cells, J. Electmchem. Soc., 2001, 148, A513-A519. 

Deimede V, Voyiatzis GA, Kallitsis JK et ai (2000) Miscibility behavior of polybenzimidazole/sulfonated polysulfone blends for use in fuel cell applications. Macromoiecuies 33 7609-7617... 

Suryani, Liu Y-L (2009) Preparation and properties of nanocomposite membranes of polybenzimidazole/ sulfonated silica nanoparticles for proton exchange membranes. J Membr Sci 332 121-128... 

Polymerization Solvent. Sulfolane can be used alone or in combination with a cosolvent as a polymerization solvent for polyureas, polysulfones, polysUoxanes, polyether polyols, polybenzimidazoles, polyphenylene ethers, poly(l,4-benzamide) (poly(imino-l,4-phenylenecarbonyl)), sUylated poly(amides), poly(arylene ether ketones), polythioamides, and poly(vinylnaphthalene/fumaronitrile) initiated by laser (134—144). Advantages of using sulfolane as a polymerization solvent include increased polymerization rate, ease of polymer purification, better solubilizing characteristics, and improved thermal stabUity. The increased polymerization rate has been attributed not only to an increase in the reaction temperature because of the higher boiling point of sulfolane, but also to a decrease in the activation energy of polymerization as a result of the contribution from the sulfonic group of the solvent. 

Poly(arylene thioether)s, 363-364 Poly(arylene thioether sulfone)s, 364 Poly(aryl sulfone) derivatives, 354 Poly(p-benzamide), synthesis of, 188-189 Polybenzimidazoles (PBIs), 265 ferrocene-containing, 315 synthesis of, 313... 

Kosmala, B. and Schauer, J. 2002. Ion-exchange membranes prepared by blending sulfonated poly(2,6-dimethyl-l,4-phenylene oxide) with polybenzimidazole. Journal of Applied Polymer Science 85 1118-1127. 

Brian Einsla was born in Wilkes-Barre, PA, in 1978. He earned his Bachelor of Science degree in 2000 in Chemistry at Virginia Polytechnic Institute and State University. He is currently a fourth-year Ph.D. candidate in the Macromolecular Science and Engineering program at VPI SU. His research interests have centered around sulfonated heterocyclic copolymers for fuel cell applications, including polyimides, polybenzoxazoles, and polybenzimidazoles. 

Sulfonation of polybenzimidazole was also accomplished by proton abstraction with an alkali metal hydride followed by reaction with sodium (4-bromomethyl)benzenesulfonate. The degree of sulfonation in this synthesis can be controlled by the... 

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. 

Considerable efforts have centered on carrying out the synthesis of polybenzimidazoles at more moderate temperatures. Polymerization of the isophthalic acid or its diphenyl ester have been successfully carried out in polyphosphoric acid or methanesulfonic acid-phosphorous pentoxide at 140-180°C, but the reaction is limited by the very low solubilities (<5%) of the reactants in that solvent. The lower reaction temperature is a consequence of activation of the carboxyl reactant via phosphorylation. Lower reaction temperatures are also achieved in hot molten nonsolvents such as sulfolane and diphenyl sulfone, but the need to remove such solvents by a filtration or solvent extraction is a disadvantage. 

MC MDI MEKP MF MMA MPEG MPF NBR NDI NR OPET OPP OSA PA PAEK PAI PAN PB PBAN PBI PBN PBS PBT PC PCD PCT PCTFE PE PEC PEG PEI PEK PEN PES PET PF PFA PI PIBI PMDI PMMA PMP PO PP PPA PPC PPO PPS PPSU Methyl cellulose Methylene diphenylene diisocyanate Methyl ethyl ketone peroxide Melamine formaldehyde Methyl methacrylate Polyethylene glycol monomethyl ether Melamine-phenol-formaldehyde Nitrile butyl rubber Naphthalene diisocyanate Natural rubber Oriented polyethylene terephthalate Oriented polypropylene Olefin-modified styrene-acrylonitrile Polyamide Poly(aryl ether-ketone) Poly(amide-imide) Polyacrylonitrile Polybutylene Poly(butadiene-acrylonitrile) Polybenzimidazole Polybutylene naphthalate Poly(butadiene-styrene) Poly(butylene terephthalate) Polycarbonate Polycarbodiimide Poly(cyclohexylene-dimethylene terephthalate) Polychlorotrifluoroethylene Polyethylene Chlorinated polyethylene Poly(ethylene glycol) Poly(ether-imide) Poly(ether-ketone) Polyethylene naphthalate Polyether sulfone Polyethylene terephthalate Phenol-formaldehyde copolymer Perfluoroalkoxy resin Polyimide Poly(isobutylene), Butyl rubber Polymeric methylene diphenylene diisocyanate Poly(methyl methacrylate) Poly(methylpentene) Polyolefins Polypropylene Polyphthalamide Chlorinated polypropylene Poly(phenylene oxide) Poly(phenylene sulfide) Poly(phenylene sulfone)... 

Microcellular foaming, bimodal cell size distributions, and high open-celled contents of molecular composites of HT-polymers were reported by Sun et al. [33], investigating blends of a rod-like polymer polybenzimidazole with an aminated PSU and poly(phenyl sulfone) by using carbon dioxide as a blowing agent. The complex foaming behavior was related to phase separation within the otherwise... 

Figure 3 shows some polymer structures of other sulfonic-acid-based materials and Fig. 4 shows the conductivity of propanesulfonated polybenzimidazole, showing the strong decrease in conductivity of PFSA above 80 °C and the much more thermally stable PBI derivative. 

Glipa, X. et al.. Synthesis and characterisation of sulfonated polybenzimidazole a highly conducting proton exchange polymer. Solid State Ionics, 97, 323, 1997. 

Rozifere, J. et al.. On the doping of sulfonated polybenzimidazole with strong bases. Solid State Ionics, 145, 61, 2001. 

Fig. 7 Chemical structures of some sulfonated polymers and a polyimide (A) sulfonated polyetheretherketone, PEEK, PSE (B) sulfonated polyphenylenesulfide, PPS (C) sulfonated polysulfone (D) poly(4,4 -biphenol) (4,4 -dichlorodiphenyl sulfone), BPSH-XX (XX is mol% of disulfdonated units) (E) sulfonated polybenzimidazole, PBI (F) polyimide.

To prepare new and inexpensive membranes, various trials have been made 196 sulfonated aromatic polyether membrane such as polyether ketones (PEEK),197 sulfonated polysulfone198 and membranes from sulfonated polyphenylene sulfide,199 phosphoric acid-doped polybenzimidazole, (PBI),200 polybenzimidazole having sulfonic acid groups,201 polybenzimidazole with phosphonic acid groups,202 a blend membrane of polybenzimidazole and sulfonated polysulfone,203 sulfonated phosphazene polymer.204... 

Polymer blends leading to high-end polymers, e.g. from sulfonated polymers (sPEEK - sulfonated polyether-etherketone, sPPSU - sulfonated polyphenyl-sulfone) combined with alkaline components (amine, imidazole, polybenzimidazole) The combination results in ionic cross-linked phases. Commercially available polymers can be modified by different sulfonation reagents. Another possibility is to combine different monomers based on block co-polymers. The conductivity can be controlled by the number of S03H groups due to the dependence of the water uptake from the number of groups ([23] and references cited therein). 

Wanga Y, Chnng TS, Gruender M. 2012. Sulfonated polybenzimidazole membranes for pervaporation dehydration of acetic acid. J. Membr. Sci. 415-416 486-495. 

Sulfonated aromatic polymers have been widely studied as alternatives to Nafion due to potentially attractive mechanical properties, thermal and chemical stability, and commercial availability of the base aromatic polymers. Aromatic polymers studied in fuel cell apphcations include sulfonated poly(p-phenylene)s, sulfonated polysulfones, sulfonated poly(ether ether ke-tone)s (SPEEKs), sulfonated polyimides (SPIs), sulfonated polyphosphazenes, and sulfonated polybenzimidazoles. Representative chemical structures of sulfonated aromatic polymers are shown in Scheme 3. Aromatic polymers are readily sulfonated using concentrated sulfuric acid, fuming sulfuric acid, chlorosulfonic acid, or sulfur trioxide. Post-sulfonation reactions suffer from a lack of control over the degree and location of functionalization, and the... 

The simplest and the most widely-used method for the synthesis of sulfonated ACPs involves sulfonation of different classes of polymers, such as substituted poly-(l,4-phenylenes) [34,35], poly-(p-xylylene [36,37]), poly-(l,4-oxyphenylenes) [38-44], poly(ether ether ketones) (PEEK) [46- 59], polyary-lenefether sulfones) [3,60-74], poly(phenylene sulfides) [75], polyphenyl-quinoxalines [76-79], polybenzimidazoles [80], polyperyleneimides [81] and some other ACPs. 

Sulfonated polybenzimidazoles have been prepared by polycondensation of sulfoterephthalic acid and disulfoisophthalic acid with 3,3 -diaminoben-zidine using high temperature solution polycondensation in PPA [150-153]. 

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