Polyetheretherketone membranes

De Bartolo, L., MoreUi, S., Rende, M., Gordano, A., and Drioh, E., New modified polyetheretherketone membrane for liver cell culture in biohybrid systems Adhesion and specific functions of isolated hepatocytes. Biomaterials, 25, 3621, 2004. 

B.Lakshmanan,W.Huang,D.01mei)er,andJ.W.Weidner. "Polyetheretherketone membranes for elevated temp>erature PEMFCs." Electrochemical and Solid-State Letters, pp. A282-A285,2003. 

Nafion membranes have also been used as porous supports to modify and improve the electrochemical properties of the membrane for fuel cell applications. Examples for such membranes are PDDA/phosphotungstic add (PWA)-Nafion composite membranes, PDDA-PSS-PAZO-Nafion membranes (PAZO poly(l-(4-(3-carboxy-4-hydroxyphenylazo) benzene sulfonamido)-l,2-ethanediyl soditrm salt), and Nafion and sulfonated polyetheretherketone membranes. ... 

Do, K. N. T. and Kim, D. 2008. Comparison of homogeneously and heterogeneously sulfonated polyetheretherketone membranes in preparation, properties and cell performance. J. Power Sources 185(l) 63-69. 

PTA dissolved in a solution containing polyetheretherketone sulfonic acid (SPEEK.) in EtOH/DMF, cast as a solid membrane, and treated with CS2CO3 and H2SO4 as above. 

Among the various materials are crosslinked PAN, polyphosphazenes, polyphe-nylenesulfide, polyetheretherketone, and various polymer blends [28-31]. Particularly interesting is the use of zeolites as filler in organic polymers, which aims at improving the performance of (silicone-based) membranes for separations in nonpolar solvents, by adding more cross-links to the membrane material [32, 33]. 

More recently cation-exchange membranes with good mechanical and chemical stability and well-controlled ion-exchange capacity are prepared by dissolving and casting a functionalized polymer such as sulfonated polysulfone, or sulfonated polyetheretherketone in an appropriate solvent, followed by casting the mixture into a film and then evaporation of the solvent [12]. 

To obtain membranes with different ion-exchange capacity the sulfonated polyetheretherketone or polysulfone can be mixed with unsulfonated polymer in a solvent such as N-methylpyrrolidone. By changing the ratio of the sulfonated to unsulfonated polymer the fixed-charge density can easily be adjusted to a desired value. 

The sulfonated polysulfone as well as polyetheretherketone can be cast as a film on a screen. After the evaporation of the solvent a reinforced membrane with excellent chemical and mechanical stabilities and good electrochemical properties is obtained. 

Figoli et al. [96,97] reported the preparation of polymeric capsules combining the phase-inversion technique with the membrane process. Polyetheretherketone (PEEKWC) capsules of different size (300-800 micrometer) and morphology (asymmetric with a porous or dense layer) have been prepared. The SEM pictures of the prepared PEEKWC capsules are shown in Figure 21.16. The capsules can find application both in chemical and in food packaging fields [98],... 

A recent study has shown that membranes made of a modified polyetheretherketone (PEEK-WC) are interesting materials for biomedical applications [23,24]. The cytocompatibility of PEEK-WC membranes was evaluated by culturing hepatocytes isolated from rat liver (Figure 43.6). The properties of PEEK-WC membranes were compared to polyurethane membranes prepared using the same technique, and commercial membranes (made of Nylon, polyethersulphone, and polyester). The results have shown that PEEK-WC membranes promoted hepatocyte adhesion most effectively and metabolic activities of cells cultured on these membranes improved significantly. 

Typical UF membrane materials are polysulfone (PS), poly ether sulfone (PES), polyetheretherketone (PEEK), cellulose acetate (CA), polyacrylonitrile (PAN), polyvinylidene fluoride (PVDF), polyimide (PI), and polyetherimide (PEI) ... 

PEMFCs have a solid ion exchange membrane made of sulfonated fluoropolymer, or a sulfonated polyetheretherketone (SPEEK) which is the electrolyte, and for the most part uses platinum catalysts. There are other materials in use for combination type membranes. It should be mentioned that currently SPEEK membranes do not hold up as well as the fluoropolymers such as Nafion , but research is ongoing to produce a more reliable and longer lasting membrane. 

Luo H, Vaivars G, Mathe M (2010) Covalent-ionically cross-linked polyetheretherketone proton exchange membrane for direct methanol fuel cell. J Power Sources 19 5197-5200... 

E. Drioli, H.-C Zhang, A study of polyetheretherketone and polyarylsulfone ultra-filtration membranes, Chimica Oggi, 11 (1989) 59-63... 

Salerno et al. cocultured human hepatocytes with human umbilical vein ECs (HUVECs) on a polyetheretherketone PU membrane to promote vascularization of an in vitro engineered liver tissue [102]. There was improved hepatocyte function and the formation of luminal structures occurred within 3 days of coculture on the PU versus hepatocyte-only samples [102]. Another study demonstrated that coculturing bone marrow-derived mesenchymal stromal cells with hepatocytes greatly reduced the secretion of stress enzymes by the hepatocytes and that the cells attached better to nanoflber PU versus unstructured PU [103]. 

Manea, C. and Mulder, M. (2002) Characterization of polymer blends of polyethersulfone/sulfonated polysulfone and polyethersulfone/sulfonated polyetheretherketone for direct methanol fuel cell applications. Journal of Membrane Science, 206 (1-2), 443-453. 

Licoccia, S., Di Vona, M.L., D Epifanio, A., Marani, D., VittadeUo, M., Jayakody, J.R., Greenbaum, S.G. (2006) Ormosil/sulfonated polyetheretherketone-based hybrid composite proton conducting membranes. Journal of the Electrochemical Society, 153, A1226-A1231. 

Chen, J., Li, D., Koshikawa, H., Asano, M., Maekawa, Y. (2010) CrossUnking and grafting of polyetheretherketone film by radiation techniques for application in fuel cells. Journal of Membrane Science, 362, 488-494. 

Espro et al. reported the oxidation of propane to the corresponding oxygenated products (n-propanol, isopropanol, propionic aldehyde and acetone) mediated by the Fe " -H202 Fenton system in a distributor/ contactor-type membrane reactor, under mild conditions. A composite Nafion/PEEKWC (a modified polyetheretherketone) catalytic membrane separates the gas (propane/helium) and liquid (Fe -H202) phases. The flat and hollow fibre multi-tubular membrane reactor configurations were compared, being the best performances achieved with the hollow fibre multi-tubular configuration. 

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