手性液晶的研究  Ⅳ.光活性(+)-对-(对"-烷氧基苯甲酰氧基)-苯甲酸-对′-(2-甲基丁氧基)-苯酚酯液晶的合成和性能

摘要: 合成了文题所述苯酚酯系列的十个化合物。代号(d)AmPABOB:分子式: R=CH_3、C_2H_5、n-C_3H_7—n-C_(10)H_(21)测定了它们的相变温度,确定了液晶相类型。其中R为C_1—C_3时,具有较宽的胆甾相;C_4—C_7有近晶A相;C_3—C_(10)存在手性近晶C相,且显示电滞回线,说明其具有铁电性。

Abstract: Ten compounds of the title series represented by (d) AmPABOB and the followingmolecular formula:where R=CH_3, C_2H_5, n-C_3H_7-n-C_(10)H_(21) have been synthesized. Phase transition tem-peratures as well as liquid crystal phase states of these compounds have been determined.The C_1-C_3 members are cholesteric liquid crystals with rather wide phate ranges whilethe C_4-C_7 ones are of the smectic A phase. It has been found through further examina-tion that there is the existence of chiral smectic C phases of C_3-C_(10) together with theirhysteresis loops, a fact quite indicative of the presence of ferroelectricity.