【作者】 赵坤；

【导师】 郑世军；

【作者基本信息】 郑州大学 ， 材料学， 2012， 硕士

【摘要】 单一聚合物线偏振白光电致发光器件主动发光,可以取代传统液晶显示器的背景光源、偏振片以及液晶盒,从而大大降低光能损耗、简化器件结构、提高显示器的亮度和视角。本文结合液晶和共轭高分子特性,设计并合成了两个系列五种共轭液晶高分子,并对聚合物的结构、相对分子量、液晶性能、光学性能等进行了表征。1.根据光学理论,蓝、黄互补色光以不同比例混合后可以得到白光。但不同发光颜色的电致发光材料结构差异大,利用蓝、黄互补色混合发光器件易发生相分离影响器件稳定性。若将蓝、黄色发光材料连接在同一高分子链上,可以得到单一聚合物白光发光材料从而解决相分离的难题。如果该聚合物能在外力作用下取向就可以制备单一聚合物线偏振白光发光材料。聚苯是典型的蓝光发光材料,聚苯撑乙烯是优良的黄光发光材料,本文将三联苯衍生物接入聚苯撑乙烯主链形成交叉共轭结构,并通过Gilch反应制备单一聚合物线偏振白光发光材料。P1侧链液晶基元在聚酰亚胺取向板表面沟槽下诱导取向,迫使高分子主链取向,进而使聚合物的交叉全共轭结构遭到破坏。结合高分子主链的黄光发射、侧链液晶基元的蓝光发射,可以得到线偏振白光,二色比为3。2.在固态下,有机小分子很容易形成各种聚集形态(激基缔合物、激基复合物或聚集体)。如果发蓝光的有机小分子聚集程度很大时,会发出长波段的互补光黄光,将蓝、黄光复合就可以得到白光。用相同的蓝光材料实现黄色发光,可以简化合成步骤,并减少因不同结构材料老化速度不同而造成的色度变化等问题,提高器件的使用寿命。本论文尝试将此种方法引入到共轭液晶高分子体系中,达到制备单一聚合物线偏振白光发光材料的目的。聚芴是一种平面性好、量子效率高、易形成聚集形态的蓝光材料。通过Yamamoto和Suzuki金属偶联催化反应制备了含不同侧基取代基密度的聚芴衍生物。P5在聚酰亚胺取向板上的退火膜,部分高分子主链形成扭转螺旋结构发射蓝光,同时另一部分高分子主链形成激基缔合物发射黄光,复合后可以得到线偏振白光,二色比为2.4。更多还原

【Abstract】 Single polymer linearly polarized white-light-emitting diodes are self-luminous, which can replace the background light source, polarizers, as well as liquid crystal cell of traditional liquid crystal displays, but also to greatly reduce the light loss, simplify the device structure, improve the brightness and viewing angle of display. Based on characteristics of liquid crystals and conjugated polymer, two series of five liquid crystalline conjugated polymers had been designed and synthesised. The polymer structure, relative molecular weight, liquid crystal properties and optical properties were characterized.1. According to optical theory, blue and yellow complementary colors can give white light when mixed with various compositions. However, different colors light-emitting materials is a large difference, and the device prepared by this way is prone to phase separation to affect the device stability. This problem can be solved by using a single polymer with white-light-emitting which synthesized by connecting the blue, yellow chromophore to the same polymer. The polymer with linearly polarized white light-emitting can be obtained if the polymer is in the orientation of the external force. Poly(p-phenylene)s is a good blue light-emitting materials, and poly(p-phenylene vinylene)s is a fine yellow light-emitting materials. In this paper, The novel liquid crystalline cross-conjugated (p-phenylene)s-poly-(p-phenylenevinylene)s hybrids were synthesized through Gilch polymerization in order to develop a kind of the polymer available for linearly polarized white-light-emitting from single chain. The P1main chain had been aligned by the virtue of orientation of side chain on the surface of rubbed polyimide and the cross-conjugated structure between mesogenic units of side chain and the polymer main chain also been destroyed. The alignment of the polymer main chain with yellow light emission was accompanied with orientation of the LC side chains with blue light emission and gave rise to a notable linearly polarized white fluorescence. The dichroic ratio (R) is3.2. Small organic molecules can easily form aggregation morphology (excimers, exciplexes, or aggregates) in the solid state. The blue emission materials with yellow emission of aggregation morphology can give white emission when the aggregation extent is large. Yellow emission come from the same blue emission materials can be simplified synthetic steps and can reduce the problem of the color changes caused by aging at different speeds due to the different structure of the materials, improve the life of the device. Such a method is introduced into the system of liquid crystal conjugated polymer, in order to achieve the goal of the preparation of a single polymer with linearly polarized white light emitting. Polyfluorenes have good planarity and high quantum efficiency, which are easy to form the aggregation morphology and blue emission materials. In this paper, the polyfluorene derivatives with different carapace densities of side group have been synthesized by Yamamoto and Suzuki metal coupling reaction. To drop the P5into the orientation microgroove of aligned polyimide annealed film, some part of the polymer main chain reverses to form spiral structure, showing blue emission, meanwhile, the other part of the polymer main chain form excimers, showing yellow emission, which was given rise to a notable linearly polarized white fluorescence. The dichroic ratio is2.4.更多还原