Thermotropic Chiral Nematic Side-chain Polymers
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چکیده
LLE Review, Volume 66 103 Low-Molar-Mass Liquid Crystals Liquid crystals (LC’s) represent a state-of-matter intermediate between a solid crystal and an isotropic liquid. A liquid crystal flows like an ordinary liquid, while other properties, such as optical and dielectric anisotropies, resemble those of a crystalline solid.1 In general, a somewhat rigid and anisomeric molecular shape (e.g., cylindrical, lath-like, or disc-like) is conducive to the realization of an LC state.2 Depending on whether temperature or concentration is the dominant factor in inducing mesomorphism, liquid crystals are generally classified into thermotropics and lyotropics.1,3 Numerous mesophases have been discovered, and they are roughly categorized as follows:
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