Thin reinforced membranes

Thin Reinforced Membrane for Improved Mechanical Properties... 

For industrial applications, where the membrane sizes are larger, reinforcement of the thin skin membrane by an appropriate support is required to maintain dimensional stability. This type of membrane consisting of a skin layer (perm-selective layer) supported by a suitable support is called a composite membrane. 

The main driving force for the development of reinforced composite membranes has been the possibility of increasing both mechanical strength and dimensional stability, leading to the feasible production of very thin membranes. As mentioned in Section 10.2.2, as the cell resistance increases proportionally to the thickness, an improvement in PEMFC performance could easily be achieved by using thin, reinforced composite membranes. From a cost perspective, such thin reinforced composites would contain much less of the expensive ionomer resin than conventional membranes. 

Very recently, Xia et al.43 reported microstructural investigations on MWCNTs which had been formed within the regular and well-aligned pores of an alumina membrane. The material was too thin (20-90 pm) to permit mechanical measurements, but different possible reinforcement mechanisms induced by the CNTs were evidenced on stressed and damaged materials,... 

US Patent 6,183,542 was issued in 2001 for a palladium membrane process. This process provides an apparatus that can handle high flow rates of gas, per unit area of membrane, while using a minimal amount of hydrogen-permeable material. This is accomplished by using stainless steel mesh elements to reinforce the thin-walled, palladium or palladium alloy membranes. This process also provides the ability to withstand large pressure gradients in opposite directions and thus will make it easier to clean membranes that have been clogged with contaminants. 

Uranous nitrate [U(N03)4] solution is used for the quantitative reduction of plutonium from loaded tributyl phosphate (TBP) phase [8]. Membrane cell technology was investigated for the production of 100% uranous nitrate solution [9], which is to be used in the partition cycle of the PUREX process in the fuel reprocessing plant. The membranes used hitherto have suffered from mechanical instability. A study was carried out at the BARC to obtain 100% uranous nitrate solution using a membrane-based electrolytic cell. The membrane used in this study was a thin polymer film reinforced with a Teflon fabric. The film was used as a separator between the anolyte and catholyte chambers, which are made of perfluorinated polymers, thus offering high thermal and chemical stability. 

The waterproofing body underneath the mat may be a plastic membrane, a thin aluminium sheet, or a bituminous/ concrete bed. These mats may be loosely placed or may be glued at certain points on the sub-layer. When placed on the concrete or on the asphalt, point forces may be exerted by the underlying aggregate. In addition, during construction activities, falling of reinforcements and other objects may induce local damage in the mat and in the... 

A novel, thin, three-layer reinforced and self-humidifying composite membrane,... 

Membrane Fabrication, Lamination and Reinforcement. The thermoplastic copolymer of TFE and PVEX monomer can be extruded or molded into a thin film by conventional methods. Extrusion is most appropriate for continuous production of large membranes because it facilitates control of film thickness. Lamination can be performed with a roll press to obtain multilayer membrane. To improve their mechanical properties, membranes are generally reinforced with an inert material such as fabric made of PTFE (67, 68), fibriled PTFE (69), or wire netting (70). 

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