Organic-Inorganic Composite Membranes

Jones, D.J. and Roziere, L, Inorganic/organic composite membranes, in Handbook of Fuel Cells Fundamentals, Technology, and Applications, 1st ed., Vielstich, W., Lamm, A., and Gasteiger, H. A., Eds., John Wiley Sons, West Sussex, England, 2003, p. 447. 

Jones DJ, Roziere J (2003) Inorganic/organic composite membranes for PEM fuel cells . In 3fielstich W, Lamm A, Gasteiger H (eds) Handbook of Fuel Cells - Fundamentals, Technology and Applications, 3. John Wiley and Sons, Chichester, UK p 447. 

J. Roziere, D. J. Jones, Inorganic-organic Composite Membranes for PEM Fuel Cells, Handbook of Fuel Cell Technology, W. Vielstich, A. Lamm, H. Gasteiger, Eds., Wiley, Vol. 3, pp. 447 55 (2003)... 

Lakshminarayana, G Nogami, M., and Kityk, I.V. (2010) Anhydrous proton conducting inorganic-organic composite membranes based on tetraethoxysilane/ ethyl-triethoxysilane/trimethylphosphate and l-butyl-3-methylimidazolium-bis (trifluoromethylsulfonyl)imide. /, Electrochem. Soc 157, B892-B899. 

Hygroscopic inorganic/organic composite membranes, in which the ionomer or polymer is blended with hydroscopic inorganic particles so that the membranes will remain hydrated at higher operating temperatures. 

Another class of inorganic/organic composite membranes, called self-humidifying polymer electrolyte membranes, have been developed, " ... 

Inorganic-organic composite membranes. (X.F. li et at. Ion exchange membranes for vanadium redox flow battery (VRB) applications. Energy Environ. Sci. 4,2011,1147-1160. Copyright 2011. Reprinted with permission from Royal Society of Chemistry.)... 

Inorganic-organic composite membrane and the MMM was developed in the initial article of te Hennepe et al. in the Journal of Membrane Science in 1987 for the separation of alcohol and water by PV (te Hennepe et al. 1987). They incorporated silicate-1 in the membrane made of rubbery PDMS to enhance the sorption of alcohols in the membrane over water, thus attempting to improve PV performance for the concentration of alcohols in the permeate from feed alcohol-water mixtures. The idea woiked successfully, as shown by Table 17.5. From the table, it is obvious that both the separation factor and total volumetric flux inaeased with an inaease in silicate content in the membrane. 

Finally functional groups can be introduced also in a membrane system with inorganic-organic composites. Care should be taken in this case to select combinations which add advantages of both components and avoid too many of the disadvantages. 

Another approach was the synthesis of inorganic/organic composite materials to influence the properties of the membrane. An overview on the state of the art of composite perflourinated membranes is given in [15]. Infiltration of a polymer carrier material with various inorganic proton conductors is subject of a patent [16]. For operation at elevated temperature, several materials have been considered, hi an early work, Nafion /Fl3P04 showed better conductivity at temperatures above 100°C compared with blank Nation and also reduced methanol permeabihty [17]. New types of polymers are also under development for better temperature stabihty one of the most advanced examples is the high-temperature material polybenzimidazole, which usually is doped with phosphoric acid [18]. 

Inorganic/PVA composites have been also considered, including sulfonic or phosphonic modified silica, titania, hydroxyapatite, heteropoly acids, zirconium phosphate, and montmorillonite. Hybrid organic-inorganic PVA composite membranes, like PVA/Ti02/PSSA, PVA/SiOa/SSA/, PVA/PWA/sPEEK/PWA, PVA/Si02/PPA, etc., have been reported. 

Inorganic-organic composites are the focus of recent attempts to develop proton exchange membranes [10-12]. Addition of a hygroscopic moiety (e.g., SiOa) to an ionomer, for example, wiU increase the water retention and also make the materials... 

Yet another unique class of inorganic membrane materials called pillared clay and carbon composite membranes has been studied for gas separation [Zhu et al., 1994]. The permeation rates of benzene, chlorobenzene and 1,3-dichlorobenzene vapors through these membranes can be different by orders of magnitude as indicated earlier. This may open the door for these types of membranes for separating organic mixtures. 

Membrane prepared my plasma polymerization Various organic and inorganic membranes Polyacrylonitrile composite membrane Plasma polymerized PERVAP 1137... 

Inorganic/Organic (Fluorinated) Composite lonomer Membranes.801... 

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