High-Silica Glasses from Particulate Gels and Optical fibers from Gels.

This memorandum contains the text of an invited lecture to be given at the Winter School on Glasses and Ceramics from Gels which will be held at the University of Sao Paolo in Sao Carlos, Brazil, in August 1989. The Proceedings of the School will be published by World Scientific Publishing Co. Particulate silica sols and gels are composed of pre-existing silica particles, sometimes stabilized in aqueous media by alkali ions. The paper reviews state-of-the-art preparation of high-silica glasses from these gels and optical fibers from such glasses. Advantages and limitations of particulate gel processes compared to alkoxide processes are discussed.