侧链液晶聚硅氧烷的合成及性能

Synthesis and properties of side-chain polysiloxanes

介绍了带有刚性侧链液晶基团的聚硅氧烷的合成， 系统论述了其链结构、取代度和相对分子质量与液晶相变温度、液晶相态温度范围、液晶相态结构等之间的关系。侧链液晶聚硅氧烷具有显著而稳定的热致液晶性， 其液晶相态温度范围可宽至３０７ ℃， 且可获得少见的柱状相液晶， 其广角 Ｘ 射线衍射谱图在０ ．４３ ～０ ．４７ ｎ ｍ 和１ ．９６ ～３ ．３１ ｎ ｍ 处出现２ 个特征峰。

The synthesis of the side-chain liquid crystalline polysiloxanes were introduced.The relationships between the chain structure,degree of substitution,relative molecular mass and liquid crystalline transition temperature,liquid crystalline phase temperature range,phase state texture were systematically reviewed with 33 references. The polysiloxanes exhibited an obvious and stable thermotropic liquid crystallinity and wide liquid crystalline temperature range up to 307 ℃,especially an unique columnar liquid crystalline phase.There were two characteristic diffraction peaks at 0.43～0.47 nm and 1.96～3.31 nm on the wide angle X-ray diffractograms of thermotropic liquid crystalline polysiloxanes.