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Author Li, Z. ♦ Zhao, W. ♦ Liu, Y. ♦ Rafailovich, M. H. ♦ Sokolov, J. ♦ Khougaz, K. ♦ Eisenberg, A. ♦ Lennox, R. B. ♦ Krausch, G.
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword CHEMISTRY ♦ MATERIALS SCIENCE ♦ COPOLYMERS ♦ TRANSMISSION ELECTRON MICROSCOPY ♦ MICELLAR SYSTEMS ♦ SOLUTIONS ♦ TOLUENE ♦ ELLIPSOMETRY ♦ THIN FILMS ♦ ANNEALING ♦ NUMERICAL DATA
Abstract It is shown experimentally that the formation of two-dimensional micelles on a solid substrate is a reversible equilibrium process in very concentrated polymer solutions. The micelles form rapidly in the dipping process when the equilibrium concentration is reached. As long as the solvent is present, the polymer chains are mobile and can organize into the specific micelle structure that minimizes the total free energy. Once the solvent has completely evaporated, the polymer becomes glassy and the micelle structures are frozen. The lamellar-cylindrical-spherical transition, upon selectively swelling one of the blocks with low molecular weight homopolymer, is quantitatively similar to the results reported by Hashimoto using bulk diblock copolymers and was explained in terms of balancing the gain in conformational free energy with the cose of bending the interface. A similar mechanism seems to be the driving force in the thin films reported here, except that in this case one must also consider the absorption energies acting at the liquid and solid interfaces in order to obtain a quantitative description. 10 refs., 3 figs., 1 tab.
ISSN 00027863
Educational Use Research
Learning Resource Type Article
Publisher Date 1996-11-06
Publisher Place United States
Journal Journal of the American Chemical Society
Volume Number 118
Issue Number 44


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