Patent · US Expired

Method for making hydrophobic non-aggregated colloidal silica

US6051672A · kind A · utility

38Cited by
7References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 24, 1998
Grant dateApr 18, 2000
Priority date
Expiry dateAug 24, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01P2006/90
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

A method for making hydrophobic non-aggregated colloidal silica comprising reacting an aqueous suspension of a hydrophilic non-aggregated colloidal silica having an average particle diameter greater than about 4 nm with a silicon compound at a pH less than about pH 4 in the presence of a sufficient quantity of a water-miscible organic solvent to facilitate contact of the hydrophilic non-aggregated colloidal silica with the silicon compound. The method is conducted at a temperature within a range of about 20.degree. C. to 250.degree. C. for a period of time sufficient to form a hydrophobic non-aggregated colloidal silica. The hydrophobic non-aggregated colloidal silicas prepared by the present method are particularly useful as fillers in silicone compositions such as adhesives, rubbers, and sealants.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.