Synthesis of novel fluorinated bis(biphenyl)diacetylene derivatives as highly birefringent nematic liquid crystalline materials
Synthesis of novel fluorinated bis(biphenyl)diacetylene derivatives as highly birefringent nematic liquid crystalline materials
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DOI：
10.1080/01411594.2015.1041952
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发表时间：
2015-06
影响因子：
1.6
通讯作者：
Y. Arakawa;Sungmin Kang;J. Watanabe;G. Konishi
中科院分区：
文献类型：
--
作者：
Y. Arakawa;Sungmin Kang;J. Watanabe;G. Konishi
合成了三种新型含氟双（联苯）丁二炔（1，4-双（联苯-4-基）丁-1，3-二炔）衍生物，它们的末端都带有烷氧基尾，可用作高双折射液晶材料。为了降低热转变温度和确定这些化合物的α相的起源，在横向位置引入氟原子。用差示扫描量热法和偏光显微镜研究了其热转变温度和介晶性质。此外，使用基于干涉法的显微镜法测量双折射率。其光学性能和光学性能不仅与氟取代基的数目有关，还与取代基的位置有关。氟含量最高的化合物表现出最低的双折射率，而仅在联苯核的内苯环上带有氟原子的化合物表现出各向异性向列相，在550 nm和140 °C下最大双折射值为0.48。
Three novel fluorinated bis(biphenyl)diacetylene (1,4-bis(biphenyl-4-yl)buta-1,3-diyne) derivatives, with alkoxy tails at the terminal positions, were prepared for use as high-birefringent nematic materials. To lower the thermal transition temperatures and determine the origin of the nematic phase of these compounds, fluorine atoms were introduced at lateral positions. Thermal transition temperatures and mesomorphic properties were investigated by differential scanning calorimetry and polarized optical microscopy. In addition, birefringence was measured using a microscopic method based on the interference method. Both the nematogenic properties and optical performances depended not only on the number of fluorine substituents, but also on the position of the substituents. The compound having the highest fluorine content exhibited the lowest birefringence, and the compound bearing fluorine atoms only on the inner benzene rings of the biphenyl cores exhibited an enantiotropic nematic phase with a maximum birefringence value of 0.48 at 550 nm and 140 °C.