Membranes surface modification and

Another alternative and less common approach for the membrane surface modification is the introduction of an active additive. The basis of this technique is the idea that those additives can move toward the top film surface during membrane formation and alter membrane surface chemistry, while keeping bulk properties unchanged. According to this method, only a very small quantity of the additives is enough to change the surface chemistry of the membranes [36], Blending is a conventional technique used for membrane surface modification, and recently, much attention... 

Membrane Surface Modification and Fonling Resistance of Hydrophilic and Hydrophobic Membranes.368... 

Khayet, M. 2004. Membrane surface modification and characterization by X-ray photoelectron spectroscopy, atomic force microscopy and contact angle measurements. 

Q Development of Membranes for Pervaporation by Membrane Surface Modification and Incorporation of Inorganic Particles... 

Due to their highly biocompatible nature, dendritic PGs have a broad range of potential applications in medicine and pharmacology. The versatility of the polyglycerol scaffolds for application in the biomedical field has recently been reviewed [131], and a number of examples were described, therein, e.g., smart and stimuli-responsive delivery and release of bioactive molecules, enhanced solubilization of hydrophobic compounds, surface-modification and regenerative therapy, as well as transport of active agents across biological barriers (cell-membranes, tumor tissue, etc.). 

Combined surface modification and management of fluid dynamics at the membrane surface are effective tools for fouling avoidance. 

This type of surface modification, if adequate functional groups are used, can be useful in incorporating silica particles into polymeric matrices (e.g., into rubber for tires) or in increasing the hydrolytic stability of high-surface-area silica (e.g., that used for membranes). Surface modification of silica is a very important principle and is widely commercialized. 

Wavhal DS and Fisher ER, Membrane surface modification by plasma-induced polymerization of acrylamide for improved surface properties and reduced protein fouling, Langmuir 2003,19, 79-85. 

J.E. Kilduff, S. Mattaraj, M. Zhou, G. Belfort, Kinetics of membrane flux decline the role of natural colloids and mitigation via membrane surface modification, J. Nanoparticle Res., 7 (2005) 525-544. 

Polymeric Membranes Surface Modification by Grafting to Method and Fabrication of Multilayered Assemblies... 

Based on the membrane surface properties and the HA properties, various researchers have attempted to change the membrane surface characteristics by surface modification. Different techniques have been performed, such as ion beam irradiation, plasma treatment, redox-initiated graft polymerization, photochemical grafting, and interfacial polymerization (IP). In this chapter, two surface modification techniques, IP and photochemical grafting, are discussed by means of experimental examples. The surface characteristics of the unmodified membrane and the modified membranes are studied and their relationships with irreversible fouling and NF performance are reported. 

Considering the obvious advantages of the membrane surface modification by SMM and the applicability of this principle in manufacturing hydrophobic/hydro-philic membranes for MD, we synthesized four different types of hydrophobic SMMs (nSMMl, nSMM2, nSMM3, and SMM41). These SMMs were then blended into PEI, which is a hydrophilic polymer, to produce novel hydrophobic/hydrophilic composite membranes by the phase inversion method. Finally, these membranes were tested for the desalination of a 0.5 M NaCl solution by DCMD. 

Khayet, M. and Matsuura, T. 2003a. Progress in membrane surface modification by surface modifying macromolecules using polyethersulfone, polyetherimide and polyvinylidene fluoride base polymers Applications in the separation processes ultrafiltration and per-vaporation. Fluid Particle Sep. J. 15(1) 9-21. 

Huang, Y.-C., Huang, C.-C., Huang, Y.-Y. and Chen, K.-S. 2007. Surface modification and characterization of chitosan or PLGA membrane with laminin by chemical and oxygen plasma treatment for neural regeneration. 

Lopez-Perez, P.M., Marques, A.P., da SUva, R.M.P., Pashkuleva, I. and Reis, R.L. 2007. Effect of chitosan membrane surface modification via plasma induced polymerization on the adhesion of osteoblast-like cells. 

Tu, C.-Y, Wang, Y.-C., Li, C.-L., Lee, K.-R., Huan, J. and Lai, J.-Y. 2005. Expanded poly(tetrafluoroethylene) membrane surface modification using acetylene/nitrogen plasma treatment. 

Yao, C., Li, X., Neoh, K.G., Shi, Z. and Kang, E.T. 2008. Surface modification and antibacterial activity of electrospun polyurethane fibrous membranes with quaternary ammoiuum moieties. 

Chapter 7 examines the use of plasma treatment for the modification of polymeric membranes. Plasma treatment is carried out at the manbrane surface so that the beneficial properties of the bulk material remain unchanged. Surface properties such as roughness and functionality can be altered to improve the performance of the membrane. All these processes are very quick and the time taken for modification is usually a few seconds up to a few minutes. The method uses chemicals in the gaseous form and produces very small amounts of wastes. Among all techniques of membrane surface modification, plasma treatment seems to be the most versatile and environment-friendly. The authors of Chapter 7 discuss how these benefits impact on membrane modification strategies. 

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