Patent · US Expired

Expandable graphite and method

US6406612B1 · kind B1 · utility

16Cited by
9References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 18, 2000
Grant dateJun 18, 2002
Priority date
Expiry dateAug 18, 2020

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC01B32/225
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Intercalated graphite flake is prepared having enhanced exfoliation characteristics in terms of at least one of reduced exfoliation temperature and increased expanded volume (also referred to as “worm volume”). The method entails contacting graphite flake with an organic expansion aid either before immersing in an aqueous intercalant solution or by dissolving the expansion aid in the aqueous intercalant solution prior to subjecting graphite flake to an electrolytic oxidation treatment therein. The graphite flake is subjected to electrolytic oxidation to provide intercalated graphite flake. Then, the intercalated graphite flake is recovered from the bulk of the intercalant solution and is preferably washed and further treated with a suitable surfactant in order to reduce the exposed gallery acids on the subsequently dried flake.

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