Study on the Fluorescence Spectra of Macromolecular Complexes of Gadolinium and Polydimethylsiloxane

Study on the Fluorescence Spectra of Poly(dimethylsiloxane) Polymer Complexes Xu Juan, Huang Xiaohua, Zhang Junsong, Zhou Ninglin, Li (College of Chemistry and Environmental Science, Nanjing Normal University, 210097, Nanjing) In the early 1960s, in 1963, Wolf and Pressley studied the fluorescence and laser properties of Eu(TTA)3 (TA*a Thiophene trifluoroacetone) in polymethyl methacrylate (PMMA), creating a rare earth. The new field of polymer research. It is well known that polymers containing luminescent rare earth ions combine the luminescence properties of rare earth ions with the ease of processing of polymers, and have broad application prospects. This article focuses on the fluorescence properties of the polymer complexes of fluorene and polydimethylsiloxane (PDMS). The results showed that the substance emits red and blue light under the excitation of ultraviolet light, and has a large luminous intensity and a long lifetime.

1 Experimental section 1.1 Reagents and instruments Reagents: The purity of Eu2O3 is more than 99.9% The remaining drugs are of analytical grade.

Instrument: The Shimadzu UV-65 UV-Vis spectrophotometer was used to determine the UV spectra of ligands and complexes. Perldn-ElmerLs50B fluorescence spectrophotometer was used to determine the fluorescence spectra of complexes and free ligands at room temperature. Both excitation and emission slits were To 5nm. 1.2 Synthesis Method 1.2 1 Trichloride Preparation of a certain amount of Eu23, heated with concentrated hydrochloric acid dissolved, evaporated to dry hydrochloric acid and then added to acetone EuCb crystals, vacuum drying EuCb crystals. The concentration of Eu3+ in the experiment was calibrated with EDTA standard solution.

1.2 Synthesis of 2Eu3+ Polydimethylsiloxane (PDMS) rare earth macromolecules A certain amount of PDMS was weighed into a round-bottomed flask, and a corresponding amount of EuCb ethanol solution was added to make the mass ratio of Eu3+/PDMA 10T6/L. The thermostatic control was stirred on a magnetic stirrer for 24 h at 24 h. 2 Results and Discussion 2.1 The ultraviolet spectrum was Eu3+ and Eu (UV absorption spectrum of the IDPDMS system. It can be seen from Table 1 that the ligand PDMS ultraviolet absorption spectrum was 201. 5nm There is an absorption band nearby, and it can be considered that the pseudo-double bond formed by dn-jK in PDMS is the Si=O fund project: National Natural Science Foundation of China (29970315), State Planning Commission Special Fund for Rare Earth (GJX01100626), Jiangsu Provincial Department of Science and Technology High Technology Research Fund (BG2001045), Jiangsu Provincial Department of Education University Natural Science Foundation (1KJB15(1)06) Correspondence: Li Ying § 1946-, Ph.D., Professor, School of Chemistry and Environmental Science, Nanjing Normal University, mainly engaged in biological inorganic and catalytic research.

Spectra of Nanjing Normal University (Natural Science Edition) Spectrogram of s Spectral group n*, Transition 14. After the rare earth forms a complex, the ultraviolet absorption light is not just an electrostatic effect, and the density of the electron cloud of the ligand is reduced, and the rare earth is biased. A certain amount of covalent bonding occurs, and the triplet energy level of the ligand is higher than the lowest excited state energy level of the rare earth ion. This is a necessary condition for the intramolecular energy transfer of the ligand rare earth ions. And this difference in energy level can neither be too large nor too small. If the triplet energy level of the ligand is much higher than the excited state energy level of the rare earth ions, energy transfer cannot be effectively performed; conversely, if the difference between the triplet energy level of the ligand and the lowest excited energy level of the rare earth ion is too small The heat deactivation rate of the ligand may be greater than the energy transfer efficiency to the rare earth ions, resulting in a weakened fluorescence emission. The absorption coefficient of Eu3+ in the ultraviolet region is very small, while the Eu(I)*PDMS complex has strong UV absorption, and the complex emits strong blue light. After the ligands absorbed light energy, energy transfer from the ligands to Eu3+ took place, and Eu3+ was excited to produce strong fluorescence emission; this means that there existed between the triplet energy level of the ligand and the lowest excited energy level of the rare earth ions. A good match Liu Li, Zhang Liqun, Jin Sun. Advances in Rare Earth/Polymer Composites Research | J. Chinese Journal of Rare Earths, 2001, 19(3)193*199 Yang Jun, Xu Yizhuang. Synthesis and Spectroscopic Characterization of Complexes of Eu3 +, U3 + and Ofloxacin J. Spectroscopy and Spectral Analysis, 200222 (5) 741 * Huang Chunhui. Rare earth coordination chemistry. Beijing: Science Press, 1997. Xue Weixing, Li Jianyu.镝 (Synthesis and fluorescence properties of UD-BDPPPD complexes. Fine Chemicals, 2002. Zhang Ting, Xu Yizhuang. Energy transfer in the luminescence of rare earth complexes. Chinese Journal of rare earths, 2001,19 (6): 543*