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:
Jan. 14, 2003
Filed:
Mar. 02, 2001
Clemens Casper, Krefeld, DE;
Jörgen Weinschenck, Krefeld, DE;
Klemens Kohlgrüber, Kürten, DE;
Jürgen Heuser, Krefeld, DE;
Christian Kords, Krefeld, DE;
Thomas Elsner, Düsseldorf, DE;
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
A process of evaporating a viscous polymer solution is described. The process includes: (a) providing a viscous polymer solution including at least 30 wt. % of solvents and monomers; (b) introducing the viscous polymer solution into a heated helix ( ), the heated helix having a vapor exit velocity of 200 to 300 m/s, (a film flow including a two-phase mixture of polymer melt, and solvent vapors and monomer vapors being formed within the helix); (c) forwarding the film flow from helix ( ) into a heated vapor separator ( ); (d) expanding the two-phase mixture of polymer melt, and solvent vapors and monomer vapors of the film flow within vapor separator ( ) at an absolute pressure of 10 mbar to 800 mbar, (a bottom product including a concentrated melt of the polymer is formed within the vapor separator); and (e) withdrawing the bottom product from vapor separator ( ). Each of the helix ( ) and vapor separator ( ) have a separate heating device, and each of heating device independently provides a temperature that is above the softening point of the polymer.