Photografting-Membranes

Piletsky SA, Matuschewski H, Schedler U, Wilpert A, Piletska EV, Thiele TA, Ulbricht M. Surface functionalization of porous polypropylene membranes with molecularly imprinted polymers by photograft copolymerization in water. Macromolecules 2000 33 3092-3098. 

Wang HY, Kobayashi T, Fujii N. Surface molecular imprinting on photosensitive dithiocar-bamoyl polyacrylonitrile membranes using photograft polymerization. J Chem Technol Biotechnol 1997 70 355-362. 

Photografting technologies, that is, the control of chemical surface functionalization by highly selective excitation with UV light, can be used for grafting to and grafting from and has been intensively explored for controlled functionalization of polymeric membranes [29]. 

An interesting pore-filled composite membrane, made by photograft copolymerization onto a solvent-stable PAN UF membrane, has been established [47]. High flux and selectivity for PV separation of organic-organic mixtures were achieved by a very thin selective barrier and prevention of swelling of the selective polymer in the pores of the barrier. 

J. -M. Clifton, M. Aptel, P. From ultrafiltration to nanofiltration hollow fiber membranes a continuous UV-photografting process. Desalination 2002, 144 (1-3), 9-14. 

From another point of view, surface photografting techniques can be categorized as liquid-phase (immersion) photografting and vapor-phase photografting. The applicability of these approaches can be extended to modification of unable-to-be-irradiated surfaces, lamination of films, patterning, membrane modification, and so on. 

Membranes Photografting is a fashionable method in the modification of polymer membranes. [ 100] Polymeric membranes play an important role in various membrane... 

A novel route to the preparation of proton-conducting membranes has been proposed by Chen et al. [127] The method consists of UV-induced photografting of styrene into polytetrafluoroethylene (PTFE) films and subsequent sulfonation (Scheme 13.21). 

Recently, Ulbricht and coworkers [131] have reported the preparation of low-fouling ultrafiltration membranes by simultaneous photograft copolymerization of hydrophilic poly(ethylene glycol) methacrylate onto a polyethersulfone (PES) membrane. A broad characterization using flux measurement and sieving curve... 

SCHEME 13.21 Preparation of proton-conducting membranes via photografting method. 

TABLE 13.4 Modification of Polymer Membranes via Photografting Method... 

Theophilline Photosensitive poly(acrylonitrile-co-diethylaminodithio-carbamoylmethylstyrene Surface imprinting membrane photograft polymerization [81]... 

Another report on the sequential photografting method deals with the grafting of poly(acrylic acid) on polypropylene membranes [16]. A linear relationship between irradiation time and average... 

Photografting has also been reported as a strategy to prepare membranes for affinity separation [145]. Functionalization of PAN has been reported for the manufacture of molecular imprinted membranes for molecular recognition. The membranes are prepared in the presence of selected templates, which are then removed leading to the formation of complementary imprinted sites [146, 147]. 

Permeation behavior of dextrans by charged ultrafiltration membranes of polyacrylonitrile photografted with ionic monomers. /, Appl. Polym. Sci, Vol.43, pp. 1037-1043. 

The photoinitiator may be loaded on the membrane surface by adsorption or may be dissolved in the monomer solution. For example, PET nucleopore membranes were modified using BP dissolved in the monomer solution following UV irradiation of the solution and the immersed membrane (Yang and Yang 2003). It was shown that photografting occurred mainly on the top membrane surface rather than in the membrane pores. This approach is relatively simple however, its main drawback is a low local concentration of BP on the membrane surface because BP moves to the membrane surface only by diffusion. This results in a low grafting efficiency. High bulk BP concentration may cause a side reaction, such as homopolymerization. In addition, the use of monomers that do not have a common solvent with BP is limited BP is almost insoluble in water. 

Bequet, S., Remigy, J.C., Rouch, J.C., Espenan, J.M., Chfton, M. and Aptel, M. 2002. From ultrafiltration to nanofiltration hollow fiber membranes A continuous UV-photografting process. Qesalinali 144 9-14. 

Susanto, H., Balakrishnan, M. and Ulbricht, M. 2007. Via surface functionalization by photograft copolymerization to low-fouling polyethersulfone-based ultrafiltration membranes.. /. Memh Sci. 288 157-167. 

Ulbricht, M. 1996. Photograft-polymer-modified microporous membranes with environment-... 

Yang, B. and Yang, W. 2003. Photografting modification of PET nucleopore membranes. ... 

C Development of Antifouling Properties and Performance of Nanofiltration Membranes by Interfacial Polymerization and Photografting Techniques... 

Akbari, A., Desclaux, S., Rouch, J.C., Aptel, P. and Remigy, J.C. 2006. New UV-photografted nanofiltration membranes for the treatment of colored textile dye effluents. J. Memb. 

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