手性近晶C(Sc)相串型液晶共聚酯的合成与表征

SYNTHESIS AND CHARACTERIZATION OF CHIRAL SMETIC C PHASE SHISH KEBAB TYPE LIQUID CRYSTALLINE COPOLYESTERS

以 2 ,5 -二 [4- ((S) - 2 -甲基丁氧基 )苯甲酰氧基 ]对苯二酚 ,4,4′-二羟基 - ,α,ω-二苯氧丁烷和对苯二甲酰氯为单体 ,采用溶液共缩聚的方法 ,合成了一系列新的手性近晶 C(Sc* )相串型液晶共聚酯。单体的结构通过元素分析、IR、1 H- NMR和 MS等方法确证。共聚物通过 GPC、DSC、TG、WAXD、偏光显微镜和旋光仪等方法表征。发现所有共聚物加热至各自的熔点以上都能形成液晶态 ,在液晶态可以观察到纹影织构或破扇形织构。通过变温 X射线衍射证明它们为手性近晶 C相。所有共聚物的熔点 (Tm)和液晶态清亮点 (Ti)随共聚物中 2 ,5 -二 [4- ((S) - 2 -甲基丁氧基 )苯甲酰氧基 ]对苯二酚用量改变呈规律性变化 ,液晶态温度范围较宽。共聚物均有很高的旋光性 。

A new series of chiral smectic C phase shish kebab type liquid crystalline copolyesters was synthesized via solution polycondensation from terephthaloyl chlorid with 2,5 bis[4 (s) 2 methylbutoxyl)benzoyloxy]hydroquinone and 4,4′ dihydroxy α,ω diphenoxybutane. The copolyesters were characterized by GPC, DSC, TG, WAXD, polarizing macroscope with heating stage and rotational analysis instrument. It was found that all the copolyesters went to liquid crystal phase when heated to their T m. The schlieren texture (or broken fan shaped texture) can be observed. Temperature variable X ray diffraction realized that they are chiral smetic C phase. Both melting temperature( T m) and isotropization temperature( T i) change regularly with varing the 2,5 bis[4 ((s) 2 methylbutoxy) benzoyoxy] hydroquinone unit content in the copolymer. It was found that the rotation was maintatined during the synthesis process and all the chiral copolymers were optically highly active.