Structural Control of Liquid Crystalline Polymers Having Non-Linear Optical Property.

以五氟苯酚和氯仿为混合溶液，采用溶液铸造法制备了4-羟基苯甲酸（HBA）和2-羟基-6-环烷酸（HNA）液晶共聚酯薄膜。研究了这些薄膜的相变和结构。在本研究中，研究了这些共聚物薄膜在拉伸过程中的精细结构变化与共聚物组成的关系。在室温和150℃（>Tg）条件下，以2mm/min的速度拉伸薄膜。尽管含有共聚物，但薄膜表现为透明。胶片在绘图后保持了透明度。当HBA=55 mol%时，薄膜的拉伸伸长率高于其他薄膜。经150℃拉伸后的薄膜伸长率约为600%。共聚物在向列态表现出磁性取向，共聚物链与磁场方向平行。在整个温度范围内，含丰富HBA的共聚物的取向系数都高于其他共聚物。共聚物的磁性取向优先取决于凝固结构的大小、它们的粘度和熔体中的热波动。在3T的磁场下进行了共聚物的成膜过程。不同的共聚物组成均可制备取向膜。富海航共聚物的双折射率高于其他共聚物。海航的高磁化率对共聚物在溶液浇注体系中的取向有影响。此外，还研究了液晶枝状大分子和液晶杯芳烃的结构控制。结果表明，在2.7 t的磁场作用下，液晶枝状大分子在近晶a中自发形成了同向取向，表现出高度取向的近晶结构，表明这些取向方法对液晶高分子材料的结构控制是有效的。少

Thin films of liquid crystalline copolyesters composed of 4-hydroxy benzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA) were prepared by solution-casting method using a mixed solution of pentafluorophenol and chloroform. The phase transitions and structures of these films has been investigated. In this study, the fine structural changes of these copolymer films during drawing process were examined in relation to copolymer composition. The films were drawn at 2mm/min at room temperature and 150℃(>Tg). The films exhibited transparent in spite of copolymer composition. The transparency of films was kept after drawing. The tensile elongation of the film with HBA=55 mol% was higher as compared with other films. The elongation of the film drawn at 150℃ was approximately 600%. The copolymer exhibited a magnetic orientation at the nematic state, and the copolymer chain was parallel to the direction of the magnetic field. The orientation coefficients of the copolymer with rich HBA were high … More er than others in the whole temperature range. The magnetic orientation of the copolymers preferentially depend on the size of coagulate structures, their viscosity, and thermal fluctuation in the melts. The film-casting procedure of the copolymers was carried out under a magnetic fields of 3T.The oriented films could be prepared in spite of different copolymer compositions. The birefringence of the copolyner with rich HNA is higher than others. The high magnetic susceptibility of HNA was effective on the orientation of the copolymers in the solution-casting system. Moreover, the structural control of liquid crystalline dendrimers and liquid crystalline calixarenes was examined. It was found that the liquid crystalline dendrimer spontaneously formed a homeotropic orientation in the smectic A.They exhibited highly oriented smectic structures under the magnetic field of 2.7 T.As a result, these orientation methods are effective on the structural control of liquid crystalline polymer materials. Less