High field /sup 1/H NMR studies of sol-gel kinetics. [Tetramethylonthosilicate in methanol and water]

Conference · Tue Dec 31 23:00:00 EST 1985

OSTI ID:5976074

Kay, B D; Assink, R A

High resolution /sup 1/H NMR spectroscopy at high magnetic fields is employed to study the reaction of the Si(OCH/sub 3/)/sub 4/:CH/sub 3/OH:H/sub 2/O sol-gel system. Both the overall extent of reaction as a function of time and the equilibrium distribution of species are measured. In acid catalyzed solution, condensation is the rate limiting step while in base catalyzed solution, hydrolysis becomes rate limiting. A kinetic model in which the rate of hydrolysis is assumed to be independent of the adjacent functional groups is presented. This model correctly predicts the distribution of product species during the initial stages of the sol-gel reaction.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5976074
• Report Number(s): SAND-85-2463C; CONF-860445-2; ON: DE86008774
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALCOHOLS
CHEMICAL REACTIONS
COLLOIDS
DECOMPOSITION
DISPERSIONS
GELS
HYDROGEN COMPOUNDS
HYDROLYSIS
HYDROXY COMPOUNDS
KINETICS
LYSIS
MAGNETIC RESONANCE
METHANOL
MIXTURES
NUCLEAR MAGNETIC RESONANCE
ORGANIC COMPOUNDS
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
RESONANCE
SILICATES
SILICON COMPOUNDS
SOL-GEL PROCESS
SOLS
SOLUTIONS
SOLVOLYSIS
WATER