Surface modifying macromolecules

Jahangir AR, McClung WG, Cornelius RM, McCloskey CB, Brash JL, Santerre JP. Fluorinated surface-modifying macromolecules modulating adhesive protein and platelet interactions on a polyether-urethane. Journal of Biomedical Materials Research 2002, 60, 135-147. 

Chemical surface modification methods of gas-separation membranes include treatment with fluorine, chlorine, bromine, or ozone. These treatments result in an increase in membrane selectivity with a decrease in flux. Cross-linking of polymers is often applied to improve the chemical stability and selectivity of membranes for reverse osmosis, pervaporation, and gas-separation applications (41). Mosqueda-Jimenez and co-workers studied the addition of surface modifying macromolecules, and the use of the additive... 

It is known that, in a polymer blend, thermodynamic incompatibility between polymers usually causes demixing of polymers. If the polymer is equilibrated in air, the polymer with the lowest surface energy (hydrophobic polymer) will concentrate at the air interface and reduce the system s interfacial tension as a consequence. The preferential adsorption of a polymer of lower surface tension at the surface was confirmed by a number of researchers for a miscible blend of two different polymers. Based on this concept, surface modifying macromolecules (SMMs) as surface-active additives were synthesized and blended into polymer solutions of polyethersulfone (PES). Depending on the hydro-phobic or hydrophilic nature of the SMM, the membrane surface becomes either more hydrophobic or more hydrophilic than the base polymeric material. ... 

Deslandes, Y. Study on the kinetics of surface migration of surface modifying macromolecules in membrane preparation. Macromolecules 2002, 35, 3017-3021. 

Khayet, M. Suk, D.E. Narbaitz, R.M. Santerre, J.P. Matsuura, T. Study on surface modification by surface-modifying macromolecules and its applications in membrane-separation processes. J. Appl. Polym. Sci. 2003, 89, 2902-2916. 

Surface modification in order to improve the hydrophilicity of membrane surface can be achieved by blending surface modifying macromolecules to the base material. Blends of phenolphthalein poly(ether sulfone) and poly(acrylonitrile-co-acrylamido methylpropane sulfonic acid), a material that contains charged groups, have been prepared. It was found... 

Pluronic FI 27 = poly (ethylene oxide)-h-poly(propylene oxide)-h-poly(ethylene oxide) (PEO-PPO-PEO). SMM, surface modifying macromolecule. Type of SMM used = L2MM. 

Abu Tarboush, B. J., Rana, D., Matsuura, T, Arafat, H. A., and Narbaitz, R. M. 2008. Preparation of thin film composite polyamide membranes for desalination using novel hydrophilic surface modifying macromolecules. Journal of Membrane Science 325 166-175. 

Rana D, Matsuura T, Narbaitz RM, Feng C. Development and characterization of novel hydrophilic surface modifying macromolecule for polymeric membranes. J. Membr. Sci. 2005 249 103. 

Khayet et al. [13] prepared flat sheet UF membranes from poly(etherimide) and correlated their UF performance with the roughness parameter and the pore size obtained by AFM. The preparation of those membranes and their mean pore sizes and roughness parameters were discussed in Chaps. 4 and 5. Table 8.4 shows the results of UF experiments together with the mean pore size and the mean roughness parameter of the membranes. From Table 8.4, it is clear that the pure water flux increases and the solute separation decreases as the pore size and the roughness parameter increase. This conclusion corroborates that of Chung et al. [11]. Similar results were obtained for asymmetric poly(etherimide )UF membranes, the surfaces of which were fluorinated by surface-modifying macromolecules [13]. 

Belong, N., Ismail, A.F., Salim, M.R., Rana, D. and Matsuura, T. 2009. Charged surface modifying macromolecule influence to polyethersulfone hollow fiber membrane with polyvinylpyrrolidone and water.Memh. Sci. 331 40-49. 

Integrating Hydrophobic Surface-Modifying Macromolecules into Hydrophilic Polymers to Produce Membranes for Membrane Distillation... 

The objectives of this chapter are to describe the fabrication of novel composite hydrophobic/hydrophilic membranes for DCMD using different surface-modifying macromolecules (SMMs) and a hydrophilic polymer polyetherimide (PEI). The membrane characteristics are related to the DCMD performance. 

FIGURE 6.1 The chemical structure of the prepared surface-modifying macromolecules. (From Qtaishat, M., Rana, D., Khayet, M., and Matsuura, T., J. Memb. ScL, 327, 264-273, 2009a. With permission.)... 

Fang, Y., Pham, V.A., Matsuura, T., Santerre, J.P. and Narbaitz, R.M. 1994. Effect of surface-modifying macromolecules and solvent evaporation time on the performance of polyethersulfone membranes for the separation of chloroform/water mixtures by per-vaporation.. 7. Ami. Polvm. ScL 54 1937-1943. 

Ho, J.Y. 1997. The effect of surface modifying macromolecules on the blood compatibility of polyethersulfone membrane intended for biomedical applications. MSc dissertation. 

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. 

Qtaishat, M., Rana, D., Matsuura, T. and Khayet, M. 2009b. Effect of surface modifying macromolecules stoichiometric ratio on composite hydrophobic/hydrophilic membranes characteristics and performance in direct contact membrane distillation. A10iE. 55(12) 3145-3151. 

Suk, D., Chowdhury, G., Matsuura, T., Narbaitz, R.M., Santerre, P., Pleizier, G. and Deslandes, Y. 2002. Study on the kinetics of surface migration of surface modifying macromolecules in membrane preparation. Q mmolead 35 3017-3021. 

Suk, D.E., Matsuura, T., Park, H.B. and Lee, Y.M. 2006. Synthesis of a new type of surface modifying macromolecules (nSMM) and characterization and testing of nSMM blended membranes for membrane distillation. 277 177-185. 

Tang, Y.W., Santerre, J.P., Labow, R.S. and Taylor, D.G. 1997b. Use of surface-modifying macromolecules to enhance the biostability of segmented polyurethanes,... 

Zhang, L., Chowdhury, G., Chaoyang, F., Matsuura, T. and Narbaitz, R. 2003. Effect of surface-modifying macromolecules and membrane morphology on fouling of polyethersulfone ultrafiltration membranes. /. Ami Pobm. Sci. 88 3132-3138. 

Mahmud et al. (2001) studied the PV performance of PES membranes prepared by incorporating surface-modifying macromolecules (SMMs). The experimental data showed that the PES-SMMs membrane appeared to be water-selective as a significant depletion of chloroform was achieved in the permeate. 

Mahmud, H., Minnery, J., Fang, Y. et al. 2001. Evaluation of membranes containing surface modifying macromolecules Determination of the chloroform separation from aqueous mixtures via pervaporation. J. Annl. Polvm. Sci. 79 183-189. 

Even though there have been various methods of SPEEK modification, there is no reported study on the surface-modifying macromolecule (SMM) approach. The next section looks at surface modification in a simpler way that is, by the addition of SMMs so that the monbrane surfaces can be modified via a single casting step. 

Mohd-Norddin, M.N.A., Ismail, A.F., Rana, D., Matsuura, T., Mustafa, A. and Tabe, A. M., 2008. Characterization and performance of proton exchange membrane for direct methanol fuel cell Blending of SPEEK with charged surface modifying macromolecules. 

Pham, V.A. 1995. Surface modifying macromolecules for enhancement of polyethersulfone pervaporation membrane performance. M.A.Sc. Thesis, University of Ottawa. 

---