Photochemical strengthening of silica aerogels modified with coumarin groups

Kevin M. Frederick, Dylan J. Boday, Jaclynn Unangst, Robert J. Stover, Zhe Li, Stephen Budy, Douglas A Loy

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Silica aerogels were silated with coumarin functionalities to allow for strengthening through the photochemical dimerization of the coumarin groups. Coumarin modified silica gels were prepared by either co-polymerizing tetramethoxysilane (TMOS) with small amounts of 7-(3-triethoxysilylpropoxy)coumarin (TEPC) or by surface modifying the silica gel with 7-(3-trimethoxysilylpropoxy)coumarin (TMPC). Aerogels, prepared by supercritical carbon dioxide drying, were irradiated with ultraviolet light (365. nm) for varying lengths of time and the flexural strength of cylindrical samples was measured. Copolymerization of TEPC with TMOS resulted in aerogels that, while initially weaker than pure silica aerogels, showed a 41% increase in flexural strength with 20. min exposure to UV. In contrast, the surface modified aerogels, while stronger than pure silica aerogels, showed no influence on flexural strength with exposure to UV.

Original languageEnglish (US)
JournalJournal of Non-Crystalline Solids
DOIs
StateAccepted/In press - Jul 31 2015

Fingerprint

Aerogels
aerogels
Silicon Dioxide
Silica
silicon dioxide
flexural strength
Bending strength
Silica Gel
Silica gel
silica gel
Dimerization
copolymerization
dimerization
Carbon Dioxide
ultraviolet radiation
Copolymerization
drying
coumarin
carbon dioxide
Carbon dioxide

Keywords

  • Coumarin modified
  • Photochemical strengthening
  • Porous materials
  • Silica aerogel
  • Silsesquioxane

ASJC Scopus subject areas

  • Condensed Matter Physics
  • Ceramics and Composites
  • Electronic, Optical and Magnetic Materials
  • Materials Chemistry

Cite this

Photochemical strengthening of silica aerogels modified with coumarin groups. / Frederick, Kevin M.; Boday, Dylan J.; Unangst, Jaclynn; Stover, Robert J.; Li, Zhe; Budy, Stephen; Loy, Douglas A.

In: Journal of Non-Crystalline Solids, 31.07.2015.

Research output: Contribution to journalArticle

Frederick, Kevin M. ; Boday, Dylan J. ; Unangst, Jaclynn ; Stover, Robert J. ; Li, Zhe ; Budy, Stephen ; Loy, Douglas A. / Photochemical strengthening of silica aerogels modified with coumarin groups. In: Journal of Non-Crystalline Solids. 2015.
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