Patent · US Expired

Perfluoropolyoxyalkylene endowed with a high viscosity and a low peroxide oxygen content, and process for preparing them

US5354922A · kind A · utility

20Cited by
10References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 22, 1992
Grant dateOct 11, 1994
Priority date
Expiry dateApr 22, 2012

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC08G63/682
  • WIPO fieldMacromolecular chemistry, polymers
  • WIPO sectorChemistry

Abstract

Peroxy perfluoropolyoxyalkylenes are prepared with high yields by carrying out the photo-oxidation of tetrafluoroethylene with molecular oxygen, by means of ultraviolet radiations, operating in the presence of pentafluorochloroethane as a solvent for tetrafluoroethylene. Thus, it is possible to obtain peroxy perfluoropolyoxyalkylenes having a viscosity at 20.degree. C. ranging from 300,000 to 8,000,000 cSt and endowed with a peroxide content not higher than 4. Such perfluoropolyoxyalkylenes provide, through chemical reduction, perfluoropolyoxyalkylenes endowed with a functionality higher than 1.9 and at the same time with a high molecular weight.

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