The side chain liquid crystal triblock copolymers (TBCs), which underwent phase transitions below their decomposition temperature, were prepared by copolymerization of poly(n-butyl acrylate) and a comonomer containing the mesogenic azobenzene group. The physical properties of TBCs in the distinctive transition temperature ranges were investigated in terms of the liquid crystal (LC) content in the copolymers. The phase transition temperatures traced optically, thermally and rheologically were well coincided one another and clearly exhibited the phase transition of smectic-nematic-isotropic with increasing temperature. In the smectic phase, increasing temperature made the liquid crystal system more elastic, but viscosity (η′) remained almost constant. In the nematic phase, increasing temperature abruptly decreased η′ andG′, ultimately leading to isotropic phase. Both smectic and nematic phases exhibited Bingham viscosity behavior but the former gave much greater yield stress at the same LC content.

中文翻译：

---

丙烯酸正丁酯与带偶氮苯的共聚单体的热致侧链三嵌段共聚物的物理性质

侧链液晶三嵌段共聚物（TBCs）在低于其分解温度的条件下经历相变，通过聚（n丙烯酸丁酯）和含有介晶的偶氮苯基的共聚单体。根据共聚物中液晶（LC）的含量，研究了独特的转变温度范围内TBC的物理性质。在光学，热学和流变学上追踪的相变温度彼此很好地重合，并且清楚地显示近晶-向列各向同性的相变随温度升高而变化。在近晶相中，温度升高使液晶系统更具弹性，但粘度（η'）几乎保持恒定。在向列相中，温度升高突然降低η'和G′，最终导致各向同性相。近晶相和向列相均显示出宾汉姆粘度行为，但是在相同的LC含量下，前者给出的屈服应力要大得多。