液晶分子在受限条件下的液晶相行为(Ⅱ)某些化学受限环境对液晶相行为的影响

Phase behaviors of liquid crystals under confined conditions(Ⅱ) Effects of some chemical confinements

综述了液晶分子在与聚合物嵌段、碳纳米管(CNT)和多面低聚倍半硅氧烷(POSS)等通过共价键形成的化学受限环境下的液晶相行为。聚合物嵌段微区的受限作用使侧链液晶嵌段共聚物的液晶有序度减小,相变温度降低。由于碳纳米管的受限作用,液晶聚合物接枝CNTs的有序结构被破坏,液晶性丧失。POSS以共价键的方式引入到液晶分子中,明显提高了液晶相的稳定性。但是当POSS含量高于某临界值后使液晶分子表现出单向性液晶相行为,甚至使其丧失液晶性。

The review summarized the researching progress on phase behaviors of LCs under chemical confinements such as polymer blocks,carbon nanotubes（CNTs） and polyhedral oligomeric silsesquioxanes（POSS） which are covalently linked with LCs.The researching results showed that the confinements of polymer blocks decrease the order degree and phases transition temperature of liquid crystalline phases in the blocking copolymers.For liquid crystalline polymer grafted CNTs,the confinements of CNTs destroy the LC ordering,and there exists no liquid crystalline phase in them.The incorporation of POSS in LCs via covalent bonds enhance the thermal stability of LC phases.However,as the content of POSS is higher the critical value,the LC molecules exhibit the monotropic liquid crystallinity,and their liquid crystallinity disappears.