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:
Sep. 20, 2005
Filed:
Dec. 28, 2001
Jean-marie Bernard, Mornant, FR;
Damien Bonneau, Saint Clement, FR;
Marc Visseau, Talant, FR;
Rhodia Chimie, Boulogne-Billancourt Cedex, FR;
Abstract
The invention concerns a method for catalytic (cyclo)condensation of monomer isocyanates, characterised in that it comprises: a) reacting starting monomer isocyanates with a catalyst comprising a mineral or organic salt of a compound of formula (I), wherein Yis selected among: a negatively charged oxygen atom, and a carbonaceous radical comprising a negative charge borne by an atom of column VB of the periodic table or by an oxygen atom advantageously by a nitrogen atom and whereof the bond with the silicon of formula (I) is borne by an atom of column VB of the periodic table, advantageously by a nitrogen atom; wherein R, Rand R, identical or different, represent a monovalent hydrocarbon radical having advantageously 1 to 30 carbon atoms, or a precursor of said compound, at a temperature of at least 20° C. and advantageously of at least 40° C. and not more than 200° C., advantageously not more than 150° C.; b) stopping the (cyclo)condensation reaction at the desired transformation rate; and c) optionally eliminating unreacted monomers or the reaction with other reactive compounds with the isocyanate function.