White light-emitting diodes (LEDs) have recently attracted particular research interest due to their possible use in full color displays combined with a color filter, such as backlights for liquid crystal displays or other lighting applications.
Particularly, white LEDs based on semiconductor polymers (PLEDs) are of interest because they can be fabricated by wet processes of the luminescent materials from solution, i.e., by a simpler and, therefore, potentially less expensive, manufacturing process in mass production, especially in the production of large-area panel displays than those fabrication techniques requiring high-vacuum deposition of small molecules. So far, a variety of strategies have been reported to realize white light-emitting based on polymer. Most of these strategies can be sought in polymer blend systems, such as polymer/polymer blend systems or polymer/small-molecule blend systems. Recently, studies in white-light emission from a single polymer incorporating a small amount of green and red-emissive component into the main chain of the macromolecule, which itself have a blue emission, have attracted research interest.
We report here the synthesis and luminescence properties of white light-emitting polymers. Though various strategies have been utilized to fabricate white polymer light-emitting diodes, two methods were used. One approach is to use a single polymer chain containing blue, green, and red (RGB) light-emitting unit, which will be dealt to chapter II, III, and IV. The other approach is to blend a red light-emitting polymer with a bluish green host polymer, which will be dealt to chapter III.
Firstly, the fabrication and characterization of single component polymeric white light-emitting diodes are reported. We have succeeded in obtaining white light emission from a single polymer chain containing RGB light-emitting units. By using Ni(0) mediated polymerization, we have systematically synthesized a series of fluorene-based copolym...