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The optical and electrical properties of the organic electroluminescent light emitting device (OLED) depends largely on the performance of the luminescent material, the luminescent material choice is very important. In full-color display, red development of materials with the blue light, the green material compared relatively backward, mainly because of the red material in the solid film state, the concentration quenching serious, can only be used as a guest material, so that cause the device fabrication repeatability bad, hard to regulate. Bandgap suitable, high-performance solid-state fluorescence quantum efficiency red material synthesized design, can be largely resolved the red material existence. In white light illumination, the the polymer electroluminescent light-emitting device (PLED) has a very broad application prospects, single white polymer electroluminescent devices in white lighting applications can become more prominent polymer processing simple, potentially competitively priced features fewer types of single white polymer materials, the color quality of the material and the luminous efficiency is a major problem, so synthesized with good luminescent properties of a single polymer white material, the current problems to be solved. In this paper, the design and synthesis of a new donor (D: donor) Suzuki coupling reaction - receptor (A: the acceptor) main red light of the linear structure of the dual dipole small molecule organic electroluminescent materials -2,7 - bithiophene-9 - the fluorenone (DTFO :2,7-di (2-thienyl) fluoren-9-one), molecular geometry optimization using density functional theory (DFT: Density Functional Theory) and predict its optical properties; characterization of its chemical structure; conducted a detailed characterization and their photophysical properties, thermal stability, and film-forming properties. The results showed that: DTFO molecular structure having a pair of anti-parallel dipole near planar structure, having a dual fluorescence phenomenon in very dilute polar solution, as the concentration increases, the aggregation induced luminescence phenomenon; DTFO solid powder having excellent the thermal stability and film-forming properties, the glass transition temperature of up to 145 ℃, the maximum emission peak at 614nm, emit red light, the color coordinates (0.66,0.34), very close to the standard red color coordinate (0.67, 0.33 ); DTFO fluorescence quantum efficiency as high as 68%, it is an ideal red organic light-emitting materials. This article in the Synthesis red material DTFO of the basis, the first fluorene DTFO copolymerization, by adjusting the molar ratio of the light emitting group to achieve a white light emission. By the synthesis of the molecular structure of the polymer, the molecular weight and molecular weight distribution, thermal properties, the photophysical properties, and electroluminescent properties of the test results show that: the ratio of the polymer, the molecular weight of the synthesized three are up to 10,000 or more, and narrow distribution; polymers have good thermal stability; as the device of ITO / the PEDOT-PSS / polymer / CA / Al of the light-emitting layer when the polymer ratio of 1000 to 1, the obtained polymer, 14.2V voltage driving, the device emitted a white light to cover the entire visible range of 400nm-700nm, color coordinates of (0.33, 0.34).
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