Preparation of 2,5-diphenyloxazole doped sol-gel glasses and their application to radio-analytical chemistry

Abstract

Transparent, colourless, monolithic sol-gel glasses doped with 2,5-diphenyloxazole (PPO) at different concentrations were prepared via the polymerisation of tetraethyl orthosilicate (TEOS) in a H₂O-AcOH-EtOH-PPO solution. The gel samples were aged at room temperature, and dried in two stages: first at room temperature, then at 70°C to reduce possible fracture. They have pore diameters in the range 1.8-2.1 nm. The leaching of PPO from the sol-gel glass was monitored using ultraviolet (UV) and X-ray photoelectron spectroscopy (XPS). The results show that the sol-gel glasses dried at the higher temperature leach less than those dried at room temperature. These sol-gel glasses, either in monolith or powder form, are effective in detecting β^– radioactivity.

References

1. Isotopes: Essential Chemistry and Applications II, ed. J. R. Jones, The Royal Society of Chemistry, London, 1988.
2. E. A. Evans, Tritium and Its Compounds, 2nd edn., Butterworths, London, 1974.
3. A. Dyer, An Introduction to Liquid Scintillation Counting, Heyden, London, 1974.
4. C. T. Peng, Sample Preparation in Liquid Scintillation Counting, The Radiochemical Centre, Amersham, 1977.
5. P. E. Ballance, A. G. Richards and R. N. Thomas, Tritium: Radiation Protection in the Laboratory, HHSC Handbook NO 11, H and H Scientific Consultants Ltd., Leeds, 1992.
6. (a) C. J. Brinker and G. W. Scherer, Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing, Academic Press, San Diego, 1989; (b) D. A. Loy and J. K. Shea, Chem. Rev., 1995, 95, 1431; (c) D. Avnir, Acc. Chem. Res., 1995, 28, 328.
7. P. W. Wong and J. D. Mackenzie, in Better Ceramics Through Chemistry, ed. C. Sanchez, M. L. Mecartney, C. J. Brinker and A. Cheetman, Mater. Res. Soc. Symp. Proc., MRS, Pittsburgh, 1994, vol. 346, p. 329.
8. B. I. Kuyavskaya, I. Gigozin, M. Ottlenghi, D. Avnir and O. Lev, J. Non-Cryst. Solids, 1992, 147–148, 808.
9. S. Braun, S. Shtelzer, S. Rappoport, D. Avnir, M. Ottolenghi and O. Lev, Anal. Chim. Acta., 1992, 256, 65.
10. L. Yang and S. S. Saavedra, Anal. Chem., 1995, 67, 1307.
11. N. Aharonson, M. Altstein, G. Avidan, D. Avnir, A. Bronshtein, A. Lewis, K. Liberman, M. Ottolenghi, Y. Polevaya, C. Pottman, J. Sammuel, S. Shalom, A. Strinkovski and A. Turniasky, in ref. 7, p. 519.
12. J. E. Lee and S. S. Saavedra, Anal. Chim. Acta, 1994, 285, 265.
13. B. D. MacCraith, V. Ruddy, C. Potter, B. O'Kelly and J. F. McGilp, Electron Lett., 1991, 27, 1247.
14. B. C. Dave, B. Dunn, J. S. Valentine and J. I. Zink, Anal. Chem., 1994, 66, 1120A.
15. D. D. Dunuwilla, B. A. Torgerson, C. K. Chang and K. A. Berglund, Anal. Chem., 1994, 66, 2739.
16. A. S. Yamanaka, F. Nishida, L. S. Ellerby, C. R. Nishida, B. Dunn, J. S. Valentine and J. I. Zink, Chem. Mater., 1992, 4, 495.
17. L. S. Ellerby, C. R. Nishida, F. Nishida, A. S. Yamanaka, B. Dunn, J. S. Valentine and J. I. Zink, Science, 1992, 25, 1113.
18. D. N. Simon, R. Czolk and H. J. Ache, Thin Solid Films, 1995, 260, 107.
19. U. Narang, P. N. Prasad, F. V. Bright, A. Kumar, N. D. Kumar, B. D. Malhotra, M. N. Kamalasanan and S. Chandra, Chem. Mater., 1994, 6, 1596.
20. K. E. Chung, E. H. Lan, M. S. Davidson, B. Dunn, J. S. Valentine and J. I. Zink, Anal. Chem., 1995, 67, 1505.
21. O. Lev, Analysis, 1992, 20, 543.
22. J. I. Dulebohn, S. C. Haefner, K. A. Berglund and K. R. Dunbar, Chem. Mater., 1992, 4, 506.
23. Coulter SA3100 Series Surface Area and Pore Size Analyser Product Manual, Coulter Corporation,, Miami, Florida, 1996.
24. A. T. Balaban, L. Birladeanu, I. Bally, P. T. Frangopol, M. Mocanu and Z. Simon, Tetrahedron, 1963, 16, 2199.
25. R. D. Braun, Introduction to Instrumental Analysis, McGraw-Hill, New York, 1987.
26. I. Hamerton, J. N. Hay, B. J. Howlin, J. R. Jones, S. Y. Lu, G. A. Webb and M. G. Bader, High Perform. Polym., 1997, 9, 281.