Patent · US Expired

Modified polytetrafluoroethylene fine powder and process for preparing the same

US6747108B1 · kind B1 · utility

5Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 12, 2001
Grant dateJun 8, 2004
Priority date
Expiry dateJan 12, 2021

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08F214/262
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

In the preparation of a modified polytetrafluoroethylene fine powder by polymerizing tetrafluoroethylene in an aqueous medium in the presence of a water soluble fluorine-containing dispersant, a fluoroalkyl vinyl ether is added to a reaction system at latest at a start of a reaction and a copolymerization reaction of the fluoroalkyl vinyl ether with tetrafluoroethylene is initiated, and a chain transfer agent is added to the reaction system after at least 80% of tetrafluoroethylene to be polymerized is consumed. The obtained modified polytetrafluoroethylene fine powder has good molding properties, in particular, extrusion properties, and high heat resistance.

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