Polymeric Membrane Preparation

Lipophilic ion exchangers traditionally used for polymeric membrane preparation are the anionic tetraphenylborate derivatives and the cationic tetraalkylammonium salts. The charges on both lipophilic ions are localized on a single (boron or nitrogen) atom, but the steric inaccessibility of the charged center, due to bulky substituents, may inhibit ion-pair formation in the membrane and provide, when necessary, non-specific interactions between ionic sites and sample ions. 

S. S. Ozdemir, M. G. Buonomenna. E. Drioli. Catalytic Polymeric Membranes Preparation and Application,General3Ql (2006) 167—183. 

Disadvantages of the known porous polymeric membrane preparation processes are that they involve additional process steps after the formation of the fiber to come to a final product. It is therefore desirable to have a more efficient preparation process. A new method to prepare structures of any geometry (Figure 3.11c through 3.1 If) and large variety of functionality... 

We can conclude the following from an Inspection of Figures 20, 21 and 22. Equation 32 gives an accurate pore size distribution function for the porous polymeric membrane prepared by the microphase separation method. The mean radius Increases and the pore size distribution broadens with S. and Pr. The reduced pore distribution N(r)S vs. r/S curve is Independent of S. but dependent on Pr. The effect of Pr on N(r) Is more remarkable than that of S. The reduced pore size distribution curves widen with an Increase In Pr. 

Ultraflltraiion membranes are commonly asymmetric (skinned) polymeric membranes prepared by the phase inversion process. Materials commercially made into membranes include cellulose nitrate, cellulose acetate, polysulfone. aramids, polyvinylidene fluoride, and nctylonitrile polymers and copolymers. Inorganic meni-braues of hydrous zirconium oxide deposited on a tubular carbon backing are also commercially available. 

Disadvantages of the known porous polymeric membrane preparation processes are that they involve additional process steps after the formation of the fiber to come to a final product. It is therefore desirable to have a more efficient preparation process. A new method to prepare structures of any geometry (Figure 6.13c through f) and large variety of functionality was recently proposed [61]. The authors proposed to incorporate the functionality by dispersion of particles in a polymeric porous structure formed by phase inversion. A slurry of dissolved polymer and particulate material can be cast as a flat film or spun into a fiber and then solidified by a phase inversion process. This concept is nowadays commercialized by Mosaic Systems. The adsorber membranes prepared via this route contain particles tightly held together within a polymeric matrix of different shapes, which can be operated either in stack of microporous flat membranes or as a bundle of solid or hollow-fiber membranes. 

Ozdemir, S.S., Buonomenna, M.G. and Drioli, E., 2006. Catalytic Polymeric Membranes Preparation and Application. Applied Catalysis a-General, 307(2) 167-183. 

Ozdemir S S, Buonomenna M G and Drioli E (2006), Catalytic polymeric membranes Preparation and application , Appl Catal A-Gen, 307, 167-183. 

Nunes SP et al. Switchable pH-responsive polymeric membranes prepared via block copolymer micelle assembly. ACS Nano 2011 5(5) 3516-3522. 

FIGURE 1.3 (a) Binary and (b) ternary phase diagrams describing TIPS and DIPS processes. (Reprinted from H. Strathmann et al., Basic Aspects in Polymeric Membrane Preparation, In E. Drioli and L. Giorno, eds., Comprehensive Membrane Science and Engineering, vol. 1 Basic Aspects of Membrane Science and Engineering, Elsevier, Amsterdam, the Netherlands, 2010, pp. 91-112, Copyright 2010, with permission from Elsevier.)... 

Zhao, Y., Qiu, C., Li, X., Vararattanavech, A., Shen, W., Torres, J., Helix-Nielsen et al. 2012, Synthesis of robust and high-performance aquaporin-based biomimetic membranes by interfacial polymerization-membrane preparation and RO performance characterization, J Memb Sci 423-424 422-428. 

Key words catalytic/inert polymeric membranes, polymeric membranes preparation, membrane reactors, extractor-type, distributor/contactor-type, forced-flow-type, polymeric inert membrane reactors (PIMRs), polymeric catalytic membrane reactors (PCMRs), modelling. 

Strathmann H, Giorno L and Drioli E (2010), Basic aspects in polymeric membrane preparation , in Drioh E and Giorno L, Comprehensive Membrane Science and Engineering, Vol. 1, Basic Aspects of Membrane Science and Engineering, Kidlington, Elsevier, 91-111. 

De Luca G, Donato L, Del Blanco S G.TasseUi F and DrioU E (2011), On the cause of controlling affinity to small molecules of imprinted polymeric membranes prepared by noncovalent approach a compntational and experimental investigation , J. Phys. Chem. B, 115,9345-9351. 

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