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. 11, 2012
Filed:
Dec. 21, 2010
Alfredo Lopez Carretero, Aljaraque, ES;
David Domingo Fuster, Oviedo, ES;
Gerardo Hidalgo Llinas, Leghorn, ES;
Ignacio Vic Fernandez, Santo Angel, ES;
Miguel Angel Salomon Cheliz, Bajo E., ES;
Alfredo Lopez Carretero, Aljaraque, ES;
David Domingo Fuster, Oviedo, ES;
Gerardo Hidalgo Llinas, Leghorn, ES;
Ignacio Vic Fernandez, Santo Angel, ES;
Miguel Angel Salomon Cheliz, Bajo E., ES;
Abstract
A method of making polycarbonate comprises polymerizing, in a melt polymerization reaction, an aromatic dihydroxy compound and a diaryl carbonate in a presence of a polymerization catalyst and producing a by-product vapor stream comprising the dihydroxy compound, the diaryl carbonate and a diaryl carbonate by-product, adding a low vapor pressure compound to the by-product vapor stream to produce a modified by-product vapor stream, introducing the modified by-product vapor stream to a separation unit, removing the volatile diaryl carbonate by-product from the modified by-product vapor stream in the separation unit to form a treated by-product stream and returning the treated by-product stream to the polymerization reaction. Alternatively, the low vapor pressure compound can be added directly to the separation unit.