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According to the basic structural characteristics of the organic light emitting material, and the poor thermal stability of existing, prone molecular association and affect the defects such as luminescent, this article to the nitrogen-containing heterocycle as the main body, through structural modification of the introduction of the means of the polymer and the like designed and synthesized three types of nine kinds of the nitrogenous heterocyclic organic light-emitting material, the system has to study the optical properties, thermal stability and other properties of the target compounds to achieve optimization of the overall performance. The specific contents are as follows: a heterocyclic imidazole as the main body, designed and synthesized by the organic light emitting material of the three imidazoles M1-3 by synthetic means on the one hand effectively replaces the the NH hydrogen on imidazol heterocyclic, thereby effectively avoiding the through hydrogen bonds between molecules of molecular association and; the other hand, the modified imidazole heterocyclic effectively grafted to the polyorganosiloxane, the steric hindrance between the molecular chains is increased, thereby hindering intermolecular aggregation, π-π stuffing reduction of the luminescent material as well as large-size crystals. The structure of the target compounds was confirmed by NMR and elemental analysis. The TGA results show that the pyrolysis temperature of M1-3 were 367.0 ° C, 426.5 ° C and 242.0 ° C, UV - visible spectroscopy, and fluorescence spectroscopy, M1-3 in DMF maximum UV absorption wavelength to 298.5 nm, respectively, 323 nm, 290 nm, maximum fluorescence emission wavelength of 375 nm, 385 nm and 408 nm. Reference method for the determination of the fluorescence quantum yield of the target compounds M1-3, respectively 0.15,0.22,0.46. 2. Nitrogen-containing heterocyclic phenanthroline as the main body, were designed and synthesized three containing phenanthroline miscellaneous organic light emitting material of the ring, L1-3, use of o-phenanthroline heterocyclic rigid planar structure and having the characteristics of a larger conjugated system, imidazole heterocycle of the luminescent material further extended on the basis of a conjugate length of the molecular system, thereby conducive to the improvement of the fluorescence properties. The structure of the target compounds was confirmed by NMR and elemental analysis. Thermogravimetric analysis results show that the pyrolysis temperature of the compound L1-3 were 337.0 ° C, 343.5 ° C and 215.0 ° C, L1-3, the thermal stability than the M1-3 is slightly lower. By UV - Vis and fluorescence spectroscopy, found that these compounds in DMF maximum UV absorption wavelength of 315 nm, 316 nm, 328 nm, its maximum fluorescence emission wavelength of 403 nm, 407 nm and 427 nm. Measured by a reference method, the fluorescence quantum yield of the target compound L1-3, the intensity of fluorescence quantum respectively 0.14,0.22,0.40 3. Designed and synthesized three imidazole, fluorenyl arm star compound S1- 3, on the one hand use of the imidazole having a good thermal stability of the characteristics, and polyfluorene have good luminescence properties, in order to optimize the comprehensive performance of the target compound; the other hand, use of the spatial three-dimensional structure of the star compound and highly branched structure, reducing the intermolecular The associative, thereby improving the luminescence properties of the compound. The structure of the target compounds was confirmed by NMR and elemental analysis. Thermogravimetric analysis results show that the S1-cleavage temperature were 239 ° C, 296 ° C, and 360 ° C, the target compounds have good thermal stability. Compounds S1-3 ethyl acetate maximum UV absorption wavelength is 308 nm, 333 nm and 348 nm, the maximum fluorescence emission wavelengths were 359 nm, 373 nm and 397 nm, and the fluorescence quantum intensity were 0.49,0.54,0.59 has good photoluminescence properties. Compounds S1-3 solid-state fluorescence emission wavelengths of 365 nm, 375 nm and 421 nm. The target compound as a solid-state fluorescence emission wavelength with the liquid when compared to the wavelength, and almost no much change, to achieve the intended purpose.
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