Polyelectrolyte complexes membranes

Polyelectrolyte complex membranes are phase-inversion membranes where polymeric anions and cations react during the gelation. The reaction is suppressed before gelation by incorporating low molecular weight electrolytes or counterions in the solvent system. Both neutral and charged membranes are formed in this manner (14,15). These membranes have not been exploited commercially because of then lack of resistance to chemicals. 

Another approach to reach delayed release from chitosan matrices are ionic interactions with polyanions. The formation of a polyelectrolyte complex membrane prevents early drug release. Via this method microcapsules can be formed between chitosan and alignate or even nanoparticles can be derived upon the complexation of chitosan with the polyanion tripolyphosphate. 

Fleming, S. The Reverse Osmosis Performance of a Polyelectrolyte Complex Membrane, Academic Press, New York (1970)... 

El-Gibaly I, Anwar MM. Development, characterization and in vivo evaluation of polyelectrolyte complex membrane gel microcapsules containing melatonin-resin complex for oral use. Bull Pharm Sci Assiut XJniv 1998 21(2) 117-139. 

The in vivo stability of a natural polyelectrolyte complex membrane, such as is formed between alginate and polylysine, (or even between synthetic polyelectrolytes) must never be assumed due to slow site-by-site displacement reactions which may occur with high molecular weight polymers (proteins, etc.) present in body fluids, and to processes of hydrolysis, enzymatically promoted or otherwise which may disrupt the membrane. 

Sato, H., Maeda, M., Nakajima, A. Mechanochemistry and permeability of polyelectrolyte complex membranes composed of poly (vinyl alcohol) derivatives. J. Appl. Polym. Sci. 1979, 23 (6), 1759-1767. 

Zhaoa Q, Quanfu FA, Yanh JB, Qiana J, Gaob C. 2011. Polyelectrolyte complex membranes for pervaporation, nanofiltration and fuel cell applications. J. Membr. Sci. 379 19—45. 

Blending is the other technique for the preparation of CS-based pervaporation membranes. Nam and Lee [29] prepared polyelectrolyte complex membranes by mixing CS and PAA (Figure 16.15) in different weight ratios. 

Schwarz HH, Apostel R, Richau K, Paul D (1992), Separation of water-alcohol mixtures through High Flux Polyelectrolyte Complex Membranes, Proc. of 6th internat. Conferences on Pervaporation Processes Ottawa, Canada (R. Bakish, ed.) Englewood, N) 223. 

Bemabe P, Peniche C., Argiielles-Monal W., Swelling behavior of chitosan/pectin polyelectrolyte complex membranes. Effect of thermal cross-linking, Polym. Bull, 55(5), 2005, 367-375. 

Barroso F., Argtielles W., Peniche C., SweUing and permeabUity of chitosan/carboxymethyl cellulose polyelectrolyte complex membranes Effect of pH and ions, Adv. Chitin ScL, 2, 1997, 573-579. 

Jiang, H., Zuo, Y, Cheng, L., Wang, H., Gu, A., Li, Y, 2011. A homogenous CS/NaCMC/n-HA polyelectrolyte complex membrane prepared by gradual electrostatic assembling. Journal of Materials Science Materials in Medicine 22 (2), 289-297. 

Interpenetrating Polymer Network IPN usually constructed within polyelectrolyte complex membranes leads to an enhanced compatibility between the two polymers and thus a synergistic effect to suppress methanol crossover [11,12,18,19]. Manbranes with an IPN structure formed by a cationic polyelectrolyte and an anionic polyelectrolyte may offer a feasible solution to obtain both low methanol crossover and high proton conductivity. For example, the incorporation of PAM with cross-linking agent provides a... 

Solvent-resistant NF (SRNF) represents a fairly new and interesting application of NF in different industrial fields (e.g., food, chemical, and pharmaceutical) for purification, recovery, or recycling of oligomers, catalysts, and solvents. This process requires membranes to be able to withstand aggressive environments, with high chemical resistance, coupled with desired permeability and selectivity. Not only TFC but also integrally skinned asymmetric membranes can be used for SRNF. The most widely used polymers for the preparation of SRNF membranes are polyimide, PAN, polyelectrolyte complex membranes (PECMs), and polydimethylsiloxane (PDMS). 

Jin, H., An, Q., Zhao, Q., Qian, J., and Zhu, M. 2010. Pervaporation dehydration of ethanol by using polyelectrolyte complex membranes based on poly (N-ethyl4-vinylpyridinium bromide) and sodium carboxymethyl cellulose. J. Memb. Sci. 347 183-192. 

Li, Y. R, Jia, H. R, Cheng, Q. L., Pan, R S., and Jiang, Z. Y. 2011. Sodium alginate-gelatin polyelectrolyte complex membranes with both high water vapor permeation and high permselectivity. J. Memb. Sci. 375 304-312. 

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