Engineering of porosity in amorphous materials. Plasma oxidation of hydrocarbon templates in polysilsesquioxanes

Conference · Fri Dec 30 23:00:00 EST 1994

OSTI ID:51653

Loy, D A; Buss, R J; Assink, R A ^[1]; Shea, K J; Oviatt, H ^[2]

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1. Sandia National Labs., Albuquerque, NM (United States)
2. Univ. of California, Irvine, CA (United States)

Arylene- and alkylene-bridged polysilsesquioxanes were prepared by sol-gel processing of bis(triethoxysilyl)-arylene monomers 1--4, and alkylene monomers 5--9. The arylene polysilsesquioxanes were porous materials with surface areas as high as 830 m{sup 2}/g (BET). Treatment with an inductively coupled oxygen plasma resulted in the near quantitative removal of the arylene bridging groups and a coarsening of the pore structure. Solid state {sup 29}Si NMR was used to confirm the conversion of the sesquioxane silicons (T) to silica (Q). The alkylene-bridged polysilsesquioxanes were non-porous. Oxygen plasma treatment afforded silica gels with mesoporosity. The porosity in the silica gels appears to arise entirely from the oxidation of the alkylene spacers.

• OSTI ID: 51653
• Report Number(s): CONF-940411--; ISBN 1-55899-246-4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COLD PLASMA
INFRARED SPECTRA
NUCLEAR MAGNETIC RESONANCE
OXIDATION
PORE STRUCTURE
POROUS MATERIALS
SILICA GEL
SOL-GEL PROCESS
SURFACE AREA