Structure and growth of silica condensation polymers. [Inorganic silica polymers]

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6978635

Keefer, K D

Inorganic silicate polymers are prepared by the hydrolysis of silicon alkoxides and subsequent condensation of the resulting silanols. The structures can be described only in a statistical fashion by means of fractal geometry. The structures are controlled by the relative rates of the hydrolysis reactions which generate reactive silanol groups and the condensation reactions of those groups. Under alkaline conditions, hydrolysis tends to be slow with respect to condensation, and non-fractal colloidal structures form by a nucleation and reaction limited growth process. Under acidic condition, hydrolysis tends to be fast with respect to condensation, and ''polymeric'' fractal structures with D/sub f/ = 2.1 are formed by reaction limited cluster aggregation. The exact structure in real systems may only approach these idealized cases. 20 refs., 4 figs.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6978635
• Report Number(s): SAND-87-2313C; CONF-8711207-1; ON: DE88012959
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360601* -- Other Materials-- Preparation & Manufacture
ALKOXIDES
CHALCOGENIDES
CHEMICAL PREPARATION
CHEMICAL REACTIONS
DECOMPOSITION
HYDROLYSIS
LYSIS
MINERALS
MONOMERS
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
POLYMERIZATION
POLYMERS
SILICA
SILICATES
SILICON COMPOUNDS
SILICON OXIDES
SILOXANES
SOLVOLYSIS
SYNTHESIS