New Conducting Polymers for User as Active Layers in Light Emitting Diodes

UNIAX开发了一系列酯取代的可溶性聚（对苯）PPP，用于蓝色和紫色发光二极管（led）的有源层。合成路线简单，有利于大规模生产，并允许各种各样的衍生物-使其他路线进入蓝色发光导电聚合物看起来笨拙或过时。衍生物已被定制为在非极性溶剂如己烷或极性溶剂如乙醇中具有溶解度。直接从溶液中纺制而成的薄膜无针孔且透明，但在反射的阳光下呈现紫色或蓝色色调。报道了所制备的所有衍生物的光致发光光谱（一些衍生物的发光能量超过3.0 eV），并利用这些稳定的室温可处理的PPP衍生物之一制造了一个原型LED器件。将这项初步研究发展为具有商业吸引力的便携式显示器的目标包括净化导电聚合物活性层以优化效率，并系统地研究二极管特性（效率或“亮度”）。以及发光导通电压)与有源层厚度、透明电极接触性质和金属电子注入接触性质的函数关系。研究还将包括合成绿色发光的PPP，利用电子释放基团红移发光的发现。

UNIAX has developed a series of ester-substituted soluble poly(para-phenylenes) PPP for use as active layers in blue and violet light emitting diodes (LEDs). The synthetic route is simple, conducive to large scale, and allows for a wide variety of derivatives - making other routes into blue luminescent conducting polymers seem awkward or obsolete. Derivatives have been tailored to have solubility in non-polar solvents such as hexane or in polar solvents such as ethanol. Films spun-cast directly from solution are pinhole-free and transparent, but take on a violet or blue hue in reflected sunlight. Photoluminescent spectra for all derivatives prepared are reported (luminescence energies for some derivates exceed 3.0 eV), and the fabrication of a prototypes LED device using one of these stable room-temperature processible PPP derivatives has been achieved. The goal in developing this preliminary research into a commercially attractive portable display involves purification of the conducting polymer active layers to optimize the efficiency, and to systematically investigate diode characteristics (efficiency, or "brightness," and light emission turn-on voltage) as a function of active layer thickness, nature of the transparent electrode contact, and nature of the metal electron-injecting contact. The research will also include research into synthesizing a green luminescent PPP, making use of the finding that electron- releasing groups red-shift the luminescence.