Gel structures in leached alkali silicate glass

Conference · Sun Jan 01 04:00:00 EST 1984

OSTI ID:5041455

Bunker, B C; Headley, T J; Douglas, S C

Transmission electron microscopy of leached Na/sub 2/O.3SiO/sub 2/ and K/sub 2/O.3SiO/sub 2/ glasses showed that the hydrated glass surface is a silica rich gel which phase separates during leaching. Phase separation is initiated when pockets of an aqueous phase nucleate and grow in the hydrated silica matrix. The aqueous pockets eventually become a network of interconnected pores with a pore diameter of approx. 30 nm. In advanced stages of leaching, the remaining interconnected silica rich phase resembles an aggregation of colloidal silica particles. The observed phase separation is consistent with literature models concerning the chemistry of silica in aqueous solutions and in leached glass.

• Research Organization: Sandia National Labs., Albuquerque, NM (USA)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5041455
• Report Number(s): SAND-83-1976C; CONF-840258-4; ON: DE84009928
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALKALI METAL COMPOUNDS
CHALCOGENIDES
COLLOIDS
DISPERSIONS
DISSOLUTION
ELECTRON MICROSCOPY
GELS
GLASS
LEACHING
MICROSCOPY
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
POROSITY
POTASSIUM COMPOUNDS
POTASSIUM SILICATES
SEPARATION PROCESSES
SILICA
SILICATES
SILICON COMPOUNDS
SILICON OXIDES
SODIUM COMPOUNDS
SODIUM SILICATES
SURFACES
TRANSMISSION ELECTRON MICROSCOPY