A side-chain liquid crystal polymer(3) containing modifiable bromo groups at the terminal site of side chains was prepared by radical polymerization. Thiocyanic liquid crystal polymer(6Ⅰ ) was synthesized successfully by post-polymerization functionalization of 3(the brominated precursor) to give liquid crystal polymer(5) containing modifiable bromo groups, then substituted Br in 5 with thiocyanic salt. Another thiocyanic liquid crystal polymer(6Ⅱ ) was also synthesized by radical polymerization of a thiocyanic monomer (4) containing a mesogenic unit which was obtained from 3 by front-polymerization functionalization with thiocyanic salt. The structures were characterized by 1H NMR and IR. The chemical structures of 6Ⅰ and 6Ⅱwere identical. However, molecular weight of 6Ⅰ was higher than 6Ⅱ . 6Ⅰ and 6Ⅱ exhibited bi-layered Smectic A phase over a broad temperature range by polarized optical microscopy, differential scanning calorimeter and XRD.%采用自由基聚合制备了侧链末端含溴的可修饰性液晶高分子(3),以3为前体用硫氰酸盐进行聚合后功能化成功地合成了硫氰液晶高分子(6Ⅰ)；以3为前体采用聚合前功能化先制得含液晶基元的硫氰单体(4)；再通过自由基聚合反应合成硫氰液晶高分子(6Ⅲ).其结构经1H NMR和IR表征,6Ⅰ和6Ⅲ具有相同的化学结构,6Ⅰ的分子量更高.偏光显微镜、差示扫描量热和X-射线衍射分析结果表明,6Ⅰ和6Ⅲ在较宽温度范围内均表现出双分子层的近晶A相.
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