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:
Nov. 17, 1992
Filed:
Jan. 29, 1991
Giuseppe Marchionni, Milan, IT;
Guglielmo Gregorio, Milan, IT;
Ugo De Patto, Milan, IT;
Mario Padovan, Milan, IT;
Ausimont S.p.A., Milan, IT;
Abstract
This invention relates to a process for preparing fluoropolyethers and perfluoropolyethers having neutral and/or functional end groups and a lower molecular weight by a selective catalytic cleavage of the corresponding higher molecular weight fluoropolyethers and perfluoropolyethers, characterized in that said cleavage is carried out by operating in the presence of a catalyst system consisting of a combination of silicon dioxide with at least an oxide, a fluoride or an oxyfluoride of a metal selected from Al, Ti, V, Cr, Co. Fe, Ni, Mo, Zn, Cu, Cd, Mn, Sb, Sn, Zr, Sc, Y, La and homologs thereof, Pb, Mg, W.