Kinetic study of the reactions of chlorosilanes with porous vycor glass

Journal Article · Mon Nov 01 00:00:00 EST 1993 · Journal of Colloid and Interface Science; (United States)

DOI:https://doi.org/10.1006/jcis.1993.1433· OSTI ID:5714786

Kim, Soojin; Gavalas, G R ^[1]

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1. California Inst. of Tech., Pasadena, CA (United States). Div. of Chemistry and Chemical Engineering

The alternating reactions of SiCl[sub 4] and H[sub 2]O with the surface of Vycor glass have been studied by thermogravimetric analysis at 400--600 C. The results are interpreted by postulating two types of silanol groups (Si-OH) on the Vycor surface, paired and isolated. Reaction of SiCl[sub 4] with paired silanols proceeds by competing steps which control the total extent of silylation. Upon reaction with H[sub 2]O, all surface Si-Cl groups are hydrolyzed, reproducing Si-OH. Simultaneous silanol-silanol and silanol-surface chloride condensations eliminate H[sub 2]O or HCl to form new Si-O-Si bridges with final product silica. A kinetic model incorporating the silylation, hydrolysis, and condensation steps describes well the TGA data.

• DOE Contract Number: FG22-92PC92525
• OSTI ID: 5714786
• Journal Information: Journal of Colloid and Interface Science; (United States), Vol. 161:1; ISSN 0021-9797
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
GLASS
CHEMICAL REACTIONS
SILICON CHLORIDES
CHEMICAL REACTION KINETICS
DEHYDROCYCLIZATION
HYDROLYSIS
SILICA
SYNTHESIS
THERMAL GRAVIMETRIC ANALYSIS
CHALCOGENIDES
CHEMICAL ANALYSIS
CHLORIDES
CHLORINE COMPOUNDS
DECOMPOSITION
GRAVIMETRIC ANALYSIS
HALIDES
HALOGEN COMPOUNDS
KINETICS
LYSIS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
QUANTITATIVE CHEMICAL ANALYSIS
REACTION KINETICS
SILICON COMPOUNDS
SILICON HALIDES
SILICON OXIDES
SOLVOLYSIS
THERMAL ANALYSIS
400201* - Chemical & Physicochemical Properties