为了满足液晶母体在各种情况下的参数要求,合成了6种新型的具有2个或2个以上的2,3-二氟苯基的有较大负介电各向异性的化合物.以2,3-二氟丙基苯或2,3-二氟苯乙醚为原料,通过一系列反应合成了目标液晶单体.经过核磁共振、元素分析和质谱等方法确定了分子结构;利用示差扫描量热仪、阿贝折射仪和电容电抗测试仪等测试手段对其进行测定.实验表明,这类多氟化合物有着较大的光学各向异性(Δn=0.22~0.33)和较大负值的介电各向异性(Δε=-7.63~-12.02).该类型的多氟化合物可以用于液晶母体的调配并且改善其部分性能.这类多氟化合物原料易得、收率较高(总收率50%),极易实现工业量产.

In order to meet the different demands of the LCD,six novel polyflurinated dielectric anisotropy liquid crystalline compounds were synthesized.These compounds were synthesized from 2,3-difluoro-propylbenzene or 2,3-difluoro-1-ethoxybenzene by several steps.Their constructions were confirmed by NMR,elemental analysis and GC-MS.The parameters and the performances of these products were measured by DSC,Abbe refractometer and capacitance inductance tester.These polyfluorinated compounds have large optical anisotropy(Δn=0.22~0.33)and large negative dielectric anisotropy(Δε=-7.63~-12.02).These compounds can be used in the LCD matrix to improve partial performance of the LCD.The preparation method is of simple operation and low cost (totle yield:50%),which can also realize industrialization easily.