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21.
以9,9-双[4-4-氨基苯氧基苯基]芴(BAOFL)作为固化剂,采用非等温DSC技术,研究了BAOFL/环氧树脂(E-51、TDE-85和芴基环氧树脂)体系的固化反应动力学,利用动态热机械分析仪(DMA)和热重分析仪(TGA)测试了固化树脂的力学性能和热稳定性。结果表明,固化反应活化能与环氧树脂和固化剂的结构密切相关,芳醚的引入提高了氨基与环氧基的反应性,固化树脂呈现出优良的热性能和力学性能,其玻璃化转变温度(T)达到206~248℃,贮能模量为2.54~2.94 GPa,初始热分解温度312~375℃,700℃g时的残炭率达到15.2%~31.7%。()  相似文献   
22.
本文研究了双胺芴合成方法以及不同条件对反应的影响,探讨了不同酸盐的催化效果、催化剂用量、苯胺用量、反应温度、反应时间等因素对双胺芴产率的影响。实验结果表明,当n(苯胺):n(PhNH2?HCl):n(芴酮)=10:1.5:1时,控制反应温度在130 ℃,反应6小时,双胺芴的产率最高为88.3%。  相似文献   
23.
A novel polyamide has been successfully prepared through the reaction of 2,7‐dibromo‐9,9‐dioctylfluorene with 2,5‐dipiperazinedione in the presence of CuI, N,N′‐dimethylethylene diamine (DMEDA) and K2CO3 as base mixture and as catalyst. The structures of the monomer and the resulting model compound, as well as the structure, solution viscosity, solubility, molecular weights, thermal behavior, thermal stability, and light absorption and emission spectra of the resulting polyamide were characterized by means of FTIR, elemental analysis, 1H‐NMR, 13C‐NMR, DSC, TGA, GPC and UV–visible absorption, and fluorescence emission spectrophotometers. The polyamide possesses excellent solubility in organic solvents such as tetrahydrofuran (THF), N‐methyl‐2‐pyrrolidone (NMP), N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide (DMF), ethylacetate, acetone, ethanol, pyridine, chloroform, and toluene at room temperature. The polyamide had inherent viscosity of 0.65 dL/g, and molecular weights of Mn= 4.25 × 104 and Mw= 5.99 × 104 g/mol. The polyamide had glass transition temperature (Tg) of 138°C, and 10% weight loss at 350°C in nitrogen. The polyamide showed strong UV absorption and blue emission in solution and in solid state. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
24.
Synthesis of 9,9-bis(buthoxycarbonylethyl)fluorine(C27H34O4, Mr=422.54) with butyl acrylate as alkylation reagent and fluorene as starting material has been performed. The crystal structure was measured by using the X-ray diffraction method.The crystal belongs to monoclinic, space group P2(1)/c with parameters as: a=1.2912(1)nm, b=1.0974(1)nm, c=1.7468(1)nm, β=90.252(2), V=2.4752(4)nm3, Z=4, Dcacl=1.134 g·cm-3, λ=0.071 073 nm, μ(MoKα)=0.075mm-1, F(000)=912, R=0.0651 and wR=0.1475. X-ray analysis reveals tha...  相似文献   
25.
采用Suzuki反应合成了一系列9,9-二辛基芴、芴酮(FO)、2,7-二-(2-噻吩)-9-芴酮(DTFO)、4,7-二-(2-噻吩)-2,1,3-苯并噻二唑(DBT)的二元和三元共聚物。结果表明,通过测试聚合物的光致发光光谱(λ=365 nm),发现薄膜状态下相同配比的共聚物比稀的氯仿溶液中的能量传递更加有效。在二元共聚物中,聚芴向DBT的能量传递比FO和DTFO有效;三元共聚物中,相同配比下芴酮的发射虽然完全淬灭,但是芴酮的引入使得宽窄带隙基团间的能量传递更加有效。  相似文献   
26.
通过"Click"反应合成了几种含芴单元的共轭聚合物。以芴为起始原料,合成了N3-Ar-N3和C≡C-Ar-C≡C类单体,分别以N,N-二甲基甲酰胺(DMF)和四氢呋喃(THF)为反应溶剂,通过Cu+催化得到聚合物。芴单元具有良好的溶解性和发光效率。"Click"反应合成的含芴单元共轭聚合物在溶液中发射蓝光,在薄膜中也有一定的荧光发射。文中以不同浓度的聚合物和聚苯乙烯(PS)共混甩膜,研究聚集对发光性能的影响。新合成的聚合物具有良好的热稳定性,热分解温度在300℃以上;差示扫描量热分析(DSC)结果显示,线性聚合物在300℃以内没有明显的相转变,保持一种稳定的无定型态,对于提高材料的发光效率是有利的。  相似文献   
27.
Two novel side‐chain polymeric metal complexes (PF1 and PF2) containing 8‐hydroxyquinoline and fluorene units with Zn(II) and Cd(II) having donor‐acceptor π‐conjugated structure have been synthesized and characterized using Fourier transform infrared, 1H NMR, UV‐visible and photoluminescence spectroscopies, thermogravimetric analysis, differential scanning calorimetry, elemental analysis and cyclic voltammetry. Dye‐sensitized solar cells (DSSCs) based on PF1 and PF2 as the dye sensitizers exhibit good device performance with solar‐to‐electricity conversion efficiency up to 0.32% (Jsc = 0.83 mA cm?2, Voc = 0.62 mV and FF = 0.62) and 0.24% (Jsc = 0.69 mA cm?2, Voc = 0.59 mV and FF = 0.60), respectively, under simulated AM 1.5 G solar irradiation (100 mW cm?2). The data show that these novel polymeric metal complexes are suitable for DSSCs. Copyright © 2012 Society of Chemical Industry  相似文献   
28.
Highly thermostable low-k polymer films with potential applications as dielectric materials in microelectronic industry were synthesized starting from 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorene dianhydride and various diamines. A polyetherimide/silica nanocomposite film was obtained using methyltriethoxysilane as precursor of inorganic phase. The chemical structure was confirmed by FTIR and 1H NMR spectroscopy. Water vapor's sorption capacity, thermal stability, glass transition temperature, thermal diffusivity, specific heat, thermal conductivity, and dielectric characteristics of the films were determined. All the films exhibited excellent thermal stability, with an initial decomposition temperature in the range of 500–530°C. They showed low dielectric constant of 1.98–2.86 and low dielectric loss of 0.0037–0.011, at a frequency of 1 Hz and room temperature. The subglass γ- and β-relaxations, primary α-relaxation, and conductivity relaxation processes were discussed according to the chemical structure of the samples. Quantitative structure–property relationship (QSPR) study was conducted, and linear regression models were formulated to describe the causal relationships between different parameters and polyetherimide properties.  相似文献   
29.
本文以高效液相色谱(HPLC)作为分离手段,以偏振同步荧光法为检测手段,实现了环境样品中芴、苊的在线同时测定。本方法对芴、苊检测限分别为0.039mg/L 和0.046mg/L。将该方法用于大气、海洋沉积物样品中芴、苊的在线同时测定、结果满意。  相似文献   
30.
Novel blue‐light‐emitting fluorene derivatives 5a–c and 7a–c containing bulky and highly emissive groups, namely pyrene, 10‐phenylanthracene‐9‐yl and 10‐(4′‐diphenylaminophenyl)anthracene‐9‐yl groups, as well as hole‐injecting/transporting triarylamines were synthesized. Single crystals of compounds 5a , 5c , 7a , and 7c were grown and their crystal structures were determined by X‐ray diffraction. The four fluorene derivatives have nonplanar molecular structures, which reduce the intermolecular interaction and the likelihood of molecular aggregation or excimer formation. No unwanted long‐wavelength emission was observed in the photoluminescence (PL) spectra of the 5a–c and 7a–c thin films. Their PL spectra reveal excellent thermal stability after annealing treatment under air and ambient light. All of the six compounds show high fluorescence quantum yields and outstanding thermal stabilities. The 2‐aryl and 2,7‐diaryl substituents at the fluorene molecule have a significant effect on the photophysical properties and the thermal characteristics. The six compounds show almost the same energy levels for the highest occupied molecular orbitals (HOMOs) of about ?5.20 eV, which allows effective hole injection. The C2‐ and C7‐aryl substituents play a relatively less‐important role in the HOMO energy levels, which depend mainly on the triphenylamino groups at the C9 position. The molecular orbitals, excitation energy, and emission energy were calculated to explain the real origin of their photophysical characteristics. The HOMOs are mainly localized on the triphenylamino groups at the C9 position, while the lowest unoccupied molecular orbitals (LUMOs) have a significant orbital density at the C2‐ and/or C7‐aryl substituents. Pure‐blue‐light‐emitting diodes based on 2,7‐diaryl‐9,9‐di(triarylamino)fluorenes were fabricated.  相似文献   
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