端羟基齐聚物的合成与表征

合成具有确定端基的液晶性和非液晶性齐聚物对进一步合成液晶嵌段共聚物具有十分重要的意义。该文通过熔融缩聚的方法，合成了两种端基为羟基的齐聚物：非液晶性的聚碳酸酯和液晶性的共聚酯酰胺。采用双酚Ａ过量和控制酯交换聚合过程，可以得到具有一定分子量的聚碳酸酯齐聚物；通过在熔融酯交换反应中加入乙酰化的对苯二酚，可以提高反应体系中的羟基的浓度，以控制最终得到端羟基的共聚酯酰胺。利用傅利叶变换红外光谱仪可以证明所得到的聚合物端基的羟基结构。通过１Ｈ核磁共振谱验证了所得到的齐聚物结构，并通过偏光显微镜证明所得到的共聚酯酰胺具有向列型液晶织构。

Synthesis and characterization of hydroxy terminated oligomer

It is important for synthesis of liquid crystalline block copolymer to synthesize hydroxy terminated liquid crystalline and non liquid crystalline oligomer. Two kinds of hydroxy terminated oligomer: liquid crystalline (LC) copolyesteramide and polycarbonate were synthesized by the melt polycondensation. The polycarbonate oligomer was prepared by esterexchange reaction through adding exceeding amount of bi phenol to the reaction system. The LC copolyesteramide oligomer was synthesized by melt transesterification reaction through adding 1, 4 biacetaoxy benzene. The end groups of these oligomers were analyzed by FT IR, and the structure of copolyesteramide was approved by NMR. The conclusion is that the LC texture of the copolyesteramide is nematic by polaroid optical microscope (POM).