Charge-mosaic membranes

Membranes classified under (c) in the introductory section are of considerable importance. Most natural membranes are macroscopically non-homogeneous. In artificial membranes non-homogeneity may be introduced either deliberately (laminates, asymmetric membranes) or spuriously (e.g. skin layers on films made by extrusion). Variation of S and Dx across the membrane, i.e. in the X direction, is of particular interest non-homogeneity along the plane of the membrane is important in certain special cases, e.g. charged mosaic membranes, which are not of immediate interest here. Also asymmetric membranes prepared for the sole purpose of producing an ultrathin active layer to maximize permeation flux are outside the scope of the present discussion. 

Figure 13.5 Charge mosaic membranes, consisting of finely dispersed domains containing fixed negatively and fixed positively charged groups, are salt permeable [15]...

Figure 13.7 Piezodialysis of 0.02 M potassium chloride solution with block copolymer charge mosaic membranes [14]. Enrichment is calculated using the expression ...

C.R. Gardner, J.N. Weinstein and S.R. Caplan, Transport Properties of Charge-mosaic Membranes, Desalination 12, 19 (1973). 

R. Kiyono, Y. Asai, Y. Yamada, A. Kishihara and M. Tasaka, Anomalous water transport across cation-exchange membranes under an osmotic pressure difference in mixed aqueous solutions of hydrochloric acid and alkali metallic halide, Seni Gakkaishi, 2000, 56, 298-301 M. Tasaka, T. Okano and T. Fujimoto, Mass transport through charge-mosaic membranes, J. Membrane Sci., 1984,19, 273-288. 

G.H. Ma and T. Fukutomi, Preparation and chemical fixation of poly(4-vinylpyridine) microgel film with ordered structure, Macromolecules, 1992, 25, 1870-1875 M. Takizawa, Y. Sugimoto, S. Doi, Y. Isono, M. Nakamura, S. Horiguchi and T. Fukutomi, Fabrication of novel charge-mosaic membranes using microsphere and their application, Curr. Trends Polym. Sci., 2001, 6, 59-66. 

L.K. Platt and A. Schindler, Ionic membranes for water desalination. I. Charge mosaic membranes from blends of random copolymers, Angew. Makromol. Chem., 1971, 19, 135. 

Y. Miyaki, H. Nagamatsu, M. Iwata, K. Ohkoshi, K. Se and T. Fujimoto, Artificial membranes from multiblock copolymers. 3. Preparation and characterization of charge-mosaic membranes, Macromolecules, 1984, 17, 2231-2236 H. Itou, M. Toda, K. Ohkoshi, M. Iwata, T. Fujimoto, Y. Miyaki and T. Kataoka, Artificial membranes from multiblock copolymers. 6. Water and salt transport through a charge-mosaic membrane. Ind. Eng. Chem. Chem. Res., 1988, 27, 983-987 Y. Miyamoto, Fabrication of charge-mosaic membranes and their performance, Maku (Membrane), 1991, 16, 233-238. 

L. Liang and S. Ying, Charge-mosaic membrane from gamma-irradiated poly(styrene-butadiene-4-vinylpyridine) triblock copolymer, J. Polym. Sci., Polym. Phys., 1993, 31, 1075-1081. 

T. Fukutomi, M. Takizawa, M. Nakamura, Charge mosaic membrane and production process thereof, USP 5,543,045, Aug, 1996 A. Yamauchi, J. Tateyama, B. Itoh,... 

M. Takizawa, Y. Sugito and S. Doi, Charged mosaic membrane prepared from microsphere gel and its characterization, J. Membr. Sci., 2000, 173, 275-280. 

K. Sato, T. Sakairi, T. Yonemoto and T. Tadaki, The desalination of a mixed solution of an amino acid and an inorganic salt by means of electrodialysis with charge-mosaic membranes, J. Membr. Sci., 1995,100, 209-216. 

T. Fukuda and A. Yamauchi, Electrolyte transport through charged mosaic membranes under the presence of non-electrolytes, Kaisui Gakkaishi (Bull. Soc. Sea Water Sci.), 2002, 36, 41-46. 

T. Fukuda and A. Yamauchi, Transport behavior of amino acid across charged mosaic membrane, Bull. Chem. Soc. Jpn., 2000, 73, 2729-2732. 

Figure 9.8. The reflection coefficient a for a charge-mosaic membrane measured at a series of 2 1 concentration ratios.

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