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Phase separation in mixtures of thermotropic liquid crystals and flexible polymers

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Abstract

The spinodal equation and the concentration-induced anisotropic-isotropic transition equation of the mixtures of thermotropic liquid crystals and flexible polymers have been studied by using the molecular field theory. The calculations of the phase diagrams of this system show that, besides the isotropic classic spinodal curve, there exists an anisotropic spinodal curve which has not been reported in literature. These two spinodal curves can be linked up by the concentration-induced anisotropic-isotropic transition line. In the various phase regions, dernixing may take place due to different phase separation mechanisms. The phase equilibrium curve cannot always join the spinodal curve at a critical point. These results are considered very meaningful for the understanding of the special properties of liquid crystal/polymer composites and very useful for controlling the morphology and the performance of PDLC materials.

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Authors and Affiliations

  1. Department of Macromolecular Science, Laboratory of Molecular Engineering of Polymer, Fudan University, 200433, Shanghai, China

    Hongdong Zhang, Zhiqun Lin, Dong Yan & Yuliang Yang

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  1. Hongdong Zhang
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  2. Zhiqun Lin
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  3. Dong Yan
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  4. Yuliang Yang
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Additional information

Project supported by the National Basic Research Project—Macromolecular Condensed State, the National Natural Science Foundation of China, the Trans-Century-Talent Foundation of the State Education Commission of China and the Science and Technology, Foundation of Shanghai.

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Zhang, H., Lin, Z., Yan, D. et al. Phase separation in mixtures of thermotropic liquid crystals and flexible polymers. Sc. China Ser. B-Chem. 40, 128–136 (1997). https://doi.org/10.1007/BF02876403

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  • DOI: https://doi.org/10.1007/BF02876403

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