The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 01, 1978
Filed:
Jul. 23, 1976
Ceskoslovenska akademie ved, Prague, CS;
Abstract
The invention relates to a method for preparation of perfectly spherical particles of silicagel with controlled particle size and controlled pore diameter, which are suitable as packings for high-speed liquid chromatography and gel permeation chromatography. Free liquid silicic acid is obtained by acidifying of solutions of alkaline metal silicates in organic solvents by organic acids miscible with water in the presence of higher amine as an emulsifier and polymerized to hydrogel in the form of spherical particles. These are isolated and partially hardened by heating above 100.degree. C in a neutral organic medium, e.g. amyl acetate or dibutyl sebacate, to remove a part of water by distillation, then subjected to hydrothermal processing with water under pressure at a temperature above 150.degree. C and eventually stabilized. Chromatographic beds of silicagel particles prepared in this way may be used both with aqueous and organic eluants and exhibit very low spreading of zones and high separation efficiency comparable with commercial styrene-divinyl-benzene gels.