Abstract
The rheology of solutions of a series of styrene–butadiene diblock copolymers dissolved in a highly selective solvent, n-tetradecane, was examined in relation to the molecular dimension of the block copolymers. Micelles with precipitated S cores and dissolved B cilia are formed in the solution. Above a certain concentration and below a certain temperature, micelles in the solution are spontaneously arranged to form a regular three-dimensional array referred to as a macrolattice. Solutions having macrolattice structures exhibit nonlinear viscoelastoplastic flow, and those having no macrolattices exhibit linear viscoelastic flow. The critical concentration, at which transitions in rheology and morphology occur, may be predicted from the structural characteristics of the micelles, i.e., their size and number of molecules making up a micelle. The relationship of dynamic moduli and the molecular dimensions was examined in detail. The shorter the length of dissolved B blocks, the larger the storage modulus and the smaller the loss modulus. Two mechanisms, being the delayed relaxational motions of the dissolved B blocks and deformation of the macrolattice itself, seem responsible for the stress in the solution. The mechanism of the lattice disordering caused by heat is also discussed. A diffuse interphase between the S core and B cilia seems to play a key role in the lattice disordering.
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T. Kotaka and J. L. White, Trans. Soc. Rheol., 17, 587 (1973).
T. Masuda, Y. Matsumoto, T. Matsumoto, and S. Onogi, Nihon Reoroji Gakkaishi, 5, 135 (1977).
T. Masuda, Y. Matsumoto, and S. Onogi, J. Macromol. Sci., Phys., B17, 256 (1980).
K. Osaki, B. S. Kim, and M. Kurata, Bull. Inst. Chem. Res., Kyoto Univ., 56, 56 (1978).
T. Kotaka, T. Tanaka, and H. Inagaki, Polym. J., 3, 327 (1972).
T. Kotaka, T. Tanaka, M. Hattori, and H. Inagaki, Macromolecules, 11, 138 (1978).
H. Watanabe and T. Kotaka, Nihon Reoroji Gakkaishi, 8, 26 (1980).
H. Watanabe, T. Kotaka, T. Hashimoto, M. Shibayama, and H. Kawai, J. Rheol., 26, 153 (1982).
T. Kotaka and H. Watanabe, Nihon Reoroji Gakkaishi, 10, 24 (1982).
M. Shibayama, T. Hashimoto, and H. Kawai, Macromolecules, submitted (1982).
D. J. Meier, J. Polym. Sci., C, 26, 81 (1969).
D. J. Meier, Prep. Polym. Colloq., Soc. Polym. Jpn., 1, 83 (1977).
E. Helfand and Z. R. Wasserman, Macromolecules, 9, 879 (1976).
E. Helfand and Z. R. Wasserman, Macromolecules, 11, 960 (1978).
H. Watanabe and T. Kotaka, J. Rheol., submitted (1982).
M. Shibayama, T. Hashimoto, H. Kawai, H. Watanabe, and T. Kotaka, Macromolecules, submitted (1982).
C. Sadron and B. Gallot, Macromol. Chem., 164, 301 (1973).
M. Fujimura, T. Hashimoto, and H. Kawai, Mem. Fac. Eng., Kyoto Univ., 43(2), 224 (1981).
T. Hashimoto, S. Suehiro, M. Shibayama, K. Saijo, and H. Kawai, Polym. J., 13, 501 (1981).
see, for example, P. G. de Gennes, “Scaling Concepts in Polymer Physics,” Cornell University Press, London, 1979, Chapter 3.
M. Kurata, Y. Tsunashima, M. Iwama, and K. Kamada, “Viscosity-Molecular Weight Relationships and Unperturbed Dimensions of Linear Chain Molecules,” in J. Brandrup and E. H. Immergut, Ed., “Polymer Handbook,” 2nd ed, Wiley-Interscience, New York, 1975.
see, for example, P. J. Flory, “Statistical Mechanics of Chain Molecules,” John Wiley & Sons, New York, 1968.
J. des Cloizeaux, J. Phys. (Paris), 36, 281 (1975).
I. Noda, N. Kato, T. Kitano, and M. Nagasawa, Macromolecules, 14, 668 (1981).
see, for example, J. D. Ferry, “Viscoelastic Properties of Polymers,” John Wiley & Sons, New York, 1969.
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Watanabe, H., Kotaka, T. Rheology of Styrene–Butadiene Diblock Copolymers Dissolved in Selective Solvent: Dependence on Molecular Dimension. Polym J 14, 739–747 (1982). https://doi.org/10.1295/polymj.14.739
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DOI: https://doi.org/10.1295/polymj.14.739