【摘 要】
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A semiperfluorinated chain has been introduced into three series of lactate-based molecules,and their mesomorphic properities have been studied by DSC and opti
【机 构】
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Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences ,Shanghai 200032 , China,Shangh
【出 处】
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Chinese Journal of Chemistry
论文部分内容阅读
A semiperfluorinated chain has been introduced into three series of lactate-based molecules,and their mesomorphic properities have been studied by DSC and optical polarized microscope.An abnormal phenomenon has been found that the introduction of a triple bond in the core of the molecule,which lengthened the molecule,gave rise to a decrease in the thermal stability of chiral smectic C phase and smectic A phase.2,3-Difluoro substituents of the phenylenic structure hinder the formation of the chiral smectic C phase because of the steric effect.
A semiperfluorinated chain has been introduced into three series of lactate-based molecules, and their mesomorphic properities have been studied by DSC and optical polarized microscope. An anomalous phenomenon has been found that the introduction of a triple bond in the core of the molecule, which lengthened the molecule, gave rise to a decrease in the thermal stability of chiral smectic C phase and smectic A phase. 2, 3-Difluoro substituents of the phenylenic structure hinder the formation of the chiral smectic C phase because of the steric effect.
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