Multiblock copolymer membrane

AFM observations of the multiblock copolymer membrane supported the formation of a clear hydrophilic/hydrophobic phase-separated structure, which simultaneously had a good proton conductivity and dimensional stability. It should be mentioned here that the obtained copolymers are not complete alternating multiblock copolymers in which each hydrophilic/hydrophobic segment is alternately connected, but are random multiblock copolymers. However, the aforementioned data indicated that the polymer structure of the obtained multiblock copolymers with the chain extender system was highly controlled [36],... 

Ghassemi, H., Ndip, G. and McGrath, J. E. 2004. New multiblock copolymers of sulfonated poly(4 -phenyl-2,5-benzophenone) and polyjarylene ether sulfone) for proton exchange membranes. 11. Polymer 45 5855-5862. 

Title Multiblock Copolymers Containing Hydrophilic and Hydrophobic Segments for Proton Exchange Membrane... 

Table 13.1 Solute flux measured in well-stirred dialysis cells at 25 °C using 0.1 M feed solutions [17]. Reprinted with permission from K. Hirahara, S.-I. Takahashi, M. Iwata, T. Fujimoto and Y. Miyaki, Artificial Membranes from Multiblock Copolymers (5), Ind. Eng. Chem. Prod. Res. Dev. 305, 25. Copyright 1986, American Chemical Society and American Pharmaceutical Association...

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. 

Fig. 2 Membrane conformation of polymersomes formed by diblock (AB), triblock (ABA, BAB, ABC), multiblock copolymers and mtik-to-arm copolymers...

A.S. Badami, O. Lane, H.-S. Lee, A. Roy, J.E. McGrath, Fundamental investigations of the effect of the linkage group on the behavior of hydrophUic-hydrophobic poly(arylene ether sulfone) multiblock copolymers for proton exchange membrane fuel cells. Journal of Membrane Science 2009, 333(1-2), 1-11. 

Jang H, Islam MM, Lim Y, Lee S, Hossain MA, Hong T, et al. Synthesis and characterization of sulfonated cardo based poly(arylene ether sulfone) multiblock copolymers for proton exchange membrane. Solid State Ionics 2013. 

Badami AS, Roy A, Lee HS, Li Y, McGrath JE. Morphological investigations of disulfonated poly(arylene ether sulfone)-fe-naphthalene dianhydride-based polyimide multiblock copolymers as potential high temperature proton exchange membranes. J Membr Sci 2009 328 (l-2) 156-64. 

Chen Y, Guo R, Lee CH, Lee M, McGrath JE. Partly fluorinated poly(arylene ether ketone sulfone) hydrophihc-hydrophobic multiblock copolymers for fuel cell membranes. Int J Hydrogen Energy 2012 37(7) 6132-9. 

Ueda et al. [171] incorporated a chain extender, namely, decafluorobiphenyl, and prepared sulfonated fluorinated multiblock copolymers (Scheme 2.39) with lEC values in the range 1.71-2.08 mEq./g (as per H-NMR spectra). The sulfonated membranes... 

Kins synthesized a series of multiblock copolymers based on sulfonated copolyimides and characterized by NMR. The morphology in terms of orientational order is probed by MAS NMR on absorbed D2O showing preferential alignment in the through-plane direction. In addition, the PFG NMR along the two orthogonal membrane directions revealed water diffusion to be faster in-plane than through-plane hydrophilic channels [126]. 

D.-Y. Park, P.A. Kohl, H.W. Beckham, Anion-conductive multiblock aromatic copolymer membranes structure-property relationships, J. Phys. Chem. C 117 (2013) 15468-15477. 

Abhishek, R., Yu, X., Dunn, S., and McGrath, ).E. (2009) Influence of microstructure and chemical composition on proton exchange membrane properties of sulfonated-fluorinated hydrophilic-hydrophobic multiblock copolymers. J. Membr. Sci., 327 (1-2), 118-124. 

Yokoyama, M., Anazawa. H., Takahashi, A. and Inone, S. (1990a) Synthesis and permeation behavior of membranes from segmented multiblock copolymers containing polv(ethyiene oxide) and poly(/i-benzyl L-aspartate) blocks. Mahomol. Che.m., 191, 301-311. 

Yu X, Roy A, Dunn S, Yang J, McGrath JE (2006) Synthesis and characterization of suUbnated-fluorinated, hydrophilic-hydrophobic multiblock copolymers for proton exchange membranes. Macromol Symp 245/246 439... 

Li Y, Roy A, Badami AS, Hill M, Yang J, Dunn S, McGrath JE (2007) Synthesis and characterization of partially fluorinated hydrophobic-hydrophilic multiblock copolymers containing sulfonate groups for proton exchange membrane. J Power Sources 172 30... 

One of the significant differences between hydrocarbon ionomers and perfluoro-sulfonic acid polymers is add groups. The pKa value of benzenesulfonic acid (PhSOsH) is 2.5 and that of trifluoromethanesulfonic acid (CF3SO3H) is —13. The pKa value was estimated to be ca. 1 for sulfonated polyether ketone and ca. —6 for Nafion membranes [78]. Therefore, the effective proton concentration and proton mobility should be lower in the hydrocarbon ionomer membranes. Without appropriate molecular design such as multiblock copolymer and sulfonic acid clusters as mentioned above, hydrocarbon ionomer membranes lack well-developed ionic channels due to less pronounced hydrophilic and hydrophobic phase separation, which causes the lower proton conductivity at low humidity. 

Lee H-S, Lane O, McGrath JE (2010) Development of multiblock copolymers with novel hydroquinone-based hydrophilic blocks for proton exchange membrane (PEM) applications. J Power Sources 195 1772-1778... 

Lee H-S, Roy A, Lane O, Drum S, McGrath JE (2008) Hydrophilic-hydrophobic multiblock copolymers based on poly(arylene ether sulfone) via low-temperature coupling reactions for proton exchange membrane fuel cells. Polymer 49 715-723... 

Lee M, Park JK, Lee H-S, Lane O, Moore RB, McGrath JE, Baird DG (2009) Effects of block length and solution-casting conditions on the final morphology and properties of disulfonated poly(arylene ether sulfone) multiblock copolymer films for proton exchange membranes. Polymer 50 6129-6138... 

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