论文部分内容阅读
盘状液晶分子中引入氟代烃链并利用疏氟效应(fluorophobic effect)能有效稳定分子的柱状堆积;低对称性的盘状分子有较低的熔点和宽的介晶相温度范围.基于此,本文设计并合成了一系列半氟酯链的不对称苯并菲化合物C18H6(OCnH2n+1)4(OCH3)(O2CC2H4C6F13)(1),及相对应的不含氟化合物C18H6(OCnH2n+1)4(OCH3)(O2CC8H17)(2),n=4～8.化合物结构通过核磁和质谱表征.介晶性通过差示扫描量热法和偏光显微镜进行了研究.结果显示:化合物均为柱状互变热致液晶.含氟链化合物1a～1e与相对应的化合物2a～2e比较,有更高的熔点和清亮点.合成的多数化合物为室温液晶.
The introduction of fluorinated hydrocarbon chains into the discotic liquid crystal molecules and the use of the fluorophobic effect can effectively stabilize the columnar packing of the molecules; the low-symmetry discotic molecules have a lower melting point and a broader mesophase temperature range. In this paper, we designed and synthesized a series of asymmetric benzophenanthrene compounds C18H6 (OCnH2n + 1) 4 (OCH3) (O2CC2H4C6F13) (1) and corresponding non-fluorinated compounds C18H6 (OCnH2n + 1) 4 (OCH3) (O2CC8H17) (2), n = 4 ~ 8. The structures of the compounds were characterized by NMR and MS.The mesomorphism was studied by differential scanning calorimetry and polarized light microscope.The results showed that all the compounds were columnar Become thermotropic liquid crystal.The fluorine-containing chain compounds 1a ~ 1e have higher melting point and clearing point than the corresponding compounds 2a ~ 2e.Most compounds synthesized are room-temperature liquid crystal.