Hostname: page-component-586b7cd67f-rdxmf Total loading time: 0 Render date: 2024-11-25T12:42:03.905Z Has data issue: false hasContentIssue false
  • English
  • Français

Origin of Porosity in Arylene-Bridged Polysilsesquioxanes

Published online by Cambridge University Press:  10 February 2011

Dale W. Schaefer ,
Greg B. Beaucage ,
Douglas A. Loy ,
Tamara A. Ulibarri ,
Eric Black ,
Kenneth J. Shea  and
Richard J. Buss
Dale W. Schaefer
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–0340, [email protected]
Greg B. Beaucage
Affiliation:
Materials Science and Engineering, University of Cincinnati, Cincinnati, OH 45221–0012
Douglas A. Loy
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–0340, [email protected]
Tamara A. Ulibarri
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–0340, [email protected]
Eric Black
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–0340, [email protected]
Kenneth J. Shea
Affiliation:
Department of Chemistry, University of California Irvine, Irvine, CA 92717
Richard J. Buss
Affiliation:
Sandia National Laboratories, Albuquerque, NM 87185–0340, [email protected]
Get access

Abstract

We investigate the porosity of a series of xerogels prepared from arylene-bridged silsesquioxane xerogels as a function of organic bridging group, condensation catalyst and post-synthesis plasma treatment to remove the organic functionalities. We conclude that porosity is controlled by polymer-solvent phase separation in the solution with no evidence of organic-inorganic phase separation. As the polymer grows and crosslinks, it becomes increasingly incompatible with the solvent and eventually microphase separates. The domain structure is controlled by a balance of network elasticity and non-bonding polymer-solvent interactions. The bridging organic groups serve to ameliorate polymer-solvent incompatibility. As a result, when the polymer does eventually phase separate, the rather tightly crosslinked network limits domain size to tens of angstroms, substantially smaller than that observed in xerogels obtained from purely inorganic precursors where incompatibility drives phase separation earlier in the gelation sequence.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 435: Symposium V – Better Ceramics Through Chemistry VII , 1996 , 301
Copyright
Copyright © Materials Research Society 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Shea, K. J., Loy, D. A. and Webster, O. W., Chem. Mater. 1, 572–4 (1989).Google Scholar
2. Shea, K. J., Loy, D. A. and Webster, O. W., Polym. Mater. Sci. Eng. 63, 281–5 (1990).Google Scholar
3. Shea, K. J., Webster, O. and Loy, D. A., in Better Ceramics Through Chemistry IV, edited by (Mat. Res. Soc. Symp. Proc., 180, 1990) pp. 975–80.Google Scholar
4. Shea, K. J., Loy, D. A. and Webster, O. W., J. Am. Chem. Soc. 114, 6700–10 (1992).Google Scholar
5. Small, J. H., Shea, K. J. and Loy, D. A., J. Non Cryst. Solids 160, 234–46 (1993).Google Scholar
6. Loy, D. A., Schaefer, D. W., Beaucage, G. and Shea, K. J., Inorg, J. and Orgometallic Pol. submitted, (1996).Google Scholar
7. Loy, D. A., Shea, K. J. and Russick, E. M., in Better Ceramics Through Chemistry V, edited by pden-Smith, M. J. Ham, Klemperer, W. G. and Brinker, C. J. (Mat. Res. Soc. Symp. Proc., 271, Materials Research Society, Pittsburg, PA, 1992) pp. 699.Google Scholar
8. Voronkov, M. G. and Lavrent'yev, V. I., Top. Curr. Chem. 102, 199–236 (1982).Google Scholar
9. Wignall, G. D., Encyclopedia of Polymer Science and Engineering 10, 112–184 (1987).Google Scholar
10. Hendricks, R. W., J. Appl. Cryst. 11, 15–3 (1978).Google Scholar
11. Schaefer, D. W., Science 243, 1023 (1989).Google Scholar
12. Schmidt, P. W., in The Fractal Approach to Heterogeneous Chemistry, edited by Avnir, D. (John Wiley & Sons, New York, 1989) pp. 67–78.Google Scholar
13. Schaefer, D. W., MRS Bulletin 24 (4), 49–53 (1994).Google Scholar
14. Loy, D. A., Shea, K. J., Buss, R. J. and Assink, R. A., ACS Symposium Series 572, 122 (1994).Google Scholar
15. Keefer, K. D., in Better Ceramics Through Chemistry I1, edited by Brinker, C. J., Clark, D. E. and Ulrich, D. R. (Mat. Res. Soc. Syrup. Proc., 73, Mat. Res. Soc., Pittsburgh, PA, 1984) pp. 15–24.Google Scholar
16. Schaefer, D. W. and Keefer, K. D., in Better Ceramics Through Chemistry II, edited by Brinker, C. J. (Mat. Res. Soc. Syrup. Proc., 32, Pittsburgh, PA, 1984) pp. 1–14.Google Scholar
17. Schaefer, D. W., Pekala, R. and Beaucage, G. B., Journal of Noncrystalline Solids 186, 159–167 (1995).Google Scholar
18. Ulibarri, T. A., Beaucage, G. B., Schaefer, D. W., Olivier, B. J. and Assink, R. A., in Submicron Multiphase Materials, edited by Baney, R. H., Gilliom, L. R., Hirano, S.- I. and Schmidt, H. K. (Mat. Res. Soc. Symp. Proc., 274, Mat. Res. Soc., Pittsburgh, 1992) pp. 85–90.Google Scholar
19. Myers, S. A., Assink, R, A., Loy, D. A. and Shea, K. I., J. Am. Chem. Soc. submitted, (1996).Google Scholar
20. Shea, K. J. and Loy, D. A., J. Am. Chem. Soc. submitted, (1996).Google Scholar