含T-型和棒型两种液晶基元的主链型液晶共聚酯的合成和表征

SYNTHESIS AND CHARACTERIZATION OF MAIN CHAIN LIQUID CRYSTAL AROMATIC COPOLYESTERS WITH T SHAPED AND ROD SHAPED MESOGENIC UNITS

以４，４′（α，ω癸二酰氧）二苯甲酰氯，２（４′乙氧基苯基）对苯二酚和联苯酚为单体，通过溶液缩聚反应，合成了一系列含Ｔ型和棒型两种液晶基元的主链型芳族共聚酯．采用ＤＳＣ、偏光显微镜和Ｘ射线衍射方法研究了共聚物的液晶行为，发现所有聚合物均有很好的热致液晶性且随聚合物中联苯酚用量的改变，共聚物的熔点（Ｔｍ）和液晶态清亮点（Ｔｉ）呈规律性变化．

A series of main chain liquid crystal line aromatic copolyesters with T shaped and rod shaped mesogenic units were synthesized via solution condensation polymerizations from 4,4′ ( α,ω decanedioyloxy) dibenzoyl dichlorides with 2 (4′ ethoxy phenyl) hydroquinone and diphenol.All of the copolyesters showed thermotropic liquid crystalline behaviors as detected by using DSC,polarized microscopy and X ray diffraction.Their melting points (T m ) and isotropization temperatures ( T i ) change regularly with varying the diphenol unit content in the copolymer.