新型含酰胺键的噻二唑类液晶的合成

Synthesis and Properties of New Thiadiazole Liquid CrystallineCompounds with Amide Central Linkages

合成了以酰胺键为中心桥键的１,３,４－噻二唑衍生物３个系列共１６个新化合物．液晶性质测试表明,它们均为具有高相变温度和宽相变范围的稳定液晶化合物．说明极性的酰胺键有利于介晶性能．比较了端某碳原子数目的多寡对Ｓｃ相相变温度的影响．

Sixteen 2, 5-bisphenyl-1, 3, 4-thiadiazoles with amide central linkages were synthesized. Theirchemical structures were analyzed by IR and 1H NMR spectrometry. The liquid crystalline properties weredetermined by POM and DSC. The results show that they are all thermally stability liquid crystals andhave higher phase transition temperatures and wide phase transition temperature ranges. The paper indi-cated that the amide central linkages are more conductive to smectic phase. The effect of the carbon atomnumber of terminal group on mesomorphic properties was discussed.