稀土专外-PreparationandPropertiesofEu3+RareEarthComplexandFluorescentFiber

1、Preparation and Properties of Eu3+ Rare Earth Complex and Fluorescent FiberA novel Eu3+ rare earth complex，composed of 4-hydroxybenzol ate acid and 1，10-phenanthroline ligands was synthesizedThe ap parent morphology，composition，thermal stability and fluorescent property of the rare earth complex wer

2、e measured by TEM, Element analysis，IR，TG and Fluorescence spectrometer Based on the composition analysis，the complex structure formu la was：Eu(HOC6H4COO)3(phen) Eu(HOC6H4COO)3(phen)Eu2O3+6HCl=2EuCl3+3H2OEuCl3+phen+3HOC6H4COOH乙醇乙醇+ +浓氨水浓氨水50 50 Eu(HOC6H4COO)3(phen) H2O+3HClFig.1 TEM picture of rare

3、earth complexElements content of the complexCHNOEumeasured52.193.153.7721.5119.02calculated50.643.203.5820.4619.44 Fig.2 shows absorption IR spectra of Eu(HOC6H4COO)3(phen)H2O,DPA and phe n. The peak in the spectra of DPA at about 3391 cm-1 reveals the stretch vibration of OH in DPA，and the peaks at

4、 about 2983, 2872，2834，1608，1510，1447 and 1423 cm-1 assign to C-H stretching vibration of phenyl of DPAMoreover，2666, 2549 cm-1are the combined peaks of-COOH from DPA. In the rare earth complex, the combined peaks at about 2660，2549 and 1690 cm-1 di sappear and occur two new peaks at about 1548and 1

5、409 cm-1, assigning to asymmetric stretching vibrations and the symmetric str etching vibrations of carboxylate group sep aratelywhich shows that the chemical bonds are formed between oxygen atoms in carbox ylic group and the rare earth ions.Meanwhile，the characteristic vibration peaks of c-c(854cm-

6、1) and c-H(738cm-1 )in phen at high frequency region shift to 847 and 729 cm-1 respectivelyThis fact also reveals that the phen has also take part in coordination with the rare earthIons. In the complex，the peak at about 3418 cm-1 can be attributed to the vibrat ion of-OH from coordinated water.Thro

7、 ugh the IR analysis of both ligands andcomplex，the results of the compositions of the rare earth complex are consistent with the element analysis . The structure of the rare earth complex is illustrated in Fig.32.3 Thermal capability of rare earth complex Fig.4 shows TG curve of the rare earth com

8、plex. From the curve, it can be seen that there exist five weight loss courses，corresponding to the thermal decomposed temperature ranges as 156-186，187-243，245-309, 327-482 and 494770 In the first course,the coordinated water is lost, the third is phen, and the 4-hydroxybenzol ate acids is lost in

9、the second course and the fou- rth ranges. At last the scrap is Eu2O3. According to the thermo gravimetric analysis，it can be concluded that the structure of the rare earth complex is consistent with Fig.3, and can be det-ermined of the blending temperature and the spinning temperature range3 Fluore

10、scence spectra of rare earth complex Fig.5 displays the excitation and emission spectra of the rare earth complex. The excitat ion spectra demonstrate that the rare earth co mplex can be well excited in a relatively broad wavelength range.The optimum excitation wa velength is 310nm.It can be seen fr

11、om Fig.5(b) that there are four emission peaks of different intensities at 536.4, 592.4, 616.3 and 694.6 nm, which belong to the transition of 5D07Fj(j= 0, 1,2,4) of Eu3+ The highest intensity fluorescence peak is at 617 nm，corresponding to the transition of 5D07F2 , which indicated that the Eu3+is

12、not in the center of the rare earth complex and the complex is unsymmetrical. The fluorescent intensity of the highest emission peak was 988. 6, which reveals the complex had excellent lum inescent performance.The rare earth complex5D0 7F0 nm I5D0 7F1 nm I5D0 7F2 nm I5D0 7F4 nm IPeak positionand int

13、ensity535.5 39.5592.4 95.4616.3 988.6694.6 49.4Table 2 Fluorescence spectra peak position and intensities of the rare earth complex Table 2 shows the emission peak position,the assigned ion leveltransitions and the relative emission intensity of the complex excited by 310 nm UV-light4 FIuorescence s

14、pectra of fiber The fluorescent fiber was prepared by spinning the mixture of the rare earth complex and polypropylene resin at the weight ratio of 2.5. Fig.6 shows the fluorescent spectra of the fiber，the measured results are similar to the complex. From the spectra, the fluorescence peak positions

15、 of the fiber are at 593, 618, 652 and 701nm，which are corresponding to the transition of Among these peaks, the relative intensity of the peak at 618nm is strongest and can reach to 698，which is the characteristic emission peak of Eu3+.All of these indicate that the rare earth complex has well disp

16、ersed in polypropylene fiber and its structure and character do not change after blending spinning under high temperature, thus the fiber exhibits high fluorescence.5 Mechanical performance of fibet The rupture intensity and rupture-stretching rate are listed in Table 3 . As seen from Table 3，the av

17、erage rupture intensity is 1.75 cN / dtex, which is lower than common polypropylene fiber. This attributes to thefluorescent fiber was prepared by the small stimulated spinning machin e with low winding speed and the fiber draw ratio was low. If the spinn ing and drawing techniques were improved,the

18、 tenacity of the fluoresce nt fiber will be improved (1) A novel rare earth complex with Eu3+ and 4 -hydroxybenzolate acid and 1, 10-phenanthroline was synthesized. Through element analysis and thermo-gravimetric analysis，the structure formula of the rare earth complex was: Eu(HOOC6H4COO)3(phen)H20And it was further conformed by IR spectra(2) Research on the appearance of the complex was taken by TEM, which showed tha