Synthesis and phase behaviors of side-chain liquid-crystalline polymers containing azobenzene mesogen with the different length alkyl tail
作者:Sheng Chen、Aihua Ling、Hai-Liang Zhang
DOI:10.1002/pola.26683
日期:2013.7.1
m = 1, 2, 3, 4, 5, and 6, the polymers exhibited a monosmectic A phase in which the smectic layer period was almost identical to the side‐chain length. In addition, for m = 2, 3, 4, and 5, they presented the monosmectic C phase in low temperature; moreover, the tilt angle increased from 23.3 to 40.5°. For m = 8, 10, 14, and 18, the polymers showed a bilayer smectic A phase in which the layer spacing was
一系列侧链液晶聚合物,聚[6- [4-(4'-正烷基苯甲酸酯基)苯氧基]-甲基丙烯酸己酯] s(PMAzoCOOR m,m = 1,2,3,4,5,6 ,8、10、14和18)已通过两种合成方法制备。单体的化学结构通过1 H NMR和质谱确认。用1 H NMR和凝胶渗透色谱仪进行聚合物的分子表征。通过差示扫描量热法,偏振光学显微镜和小角度X射线散射等技术的组合研究了聚合物的相行为。对于米 = 1、2、3、4、5和6时,聚合物表现出单晶A相,其中近晶层周期几乎与侧链长度相同。另外,对于m = 2、3、4和5,它们呈现出低温下的单晶C相。而且,倾斜角从23.3°增加到40.5°。对于m = 8、10、14和18,聚合物显示双层近晶A相,其中层间距大于完全延伸的侧链但小于两个延伸的链。另一方面,对于结算点,随着m的增加,它先减少,然后增加。所有这些表明,烷基尾的长度在这些聚合物的相行为中起重要作用。©2013