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. 09, 1999
Filed:
Sep. 23, 1998
Heinz Auer, Neulusseim, DE;
Klaus Beiser, Eppelsheim, DE;
Jurgen Ciprian, Ludwigshafen, DE;
Lothar Franz, Mutterstadt, DE;
Wolfgang Franzischka, Frankenthal, DE;
Ulrich-Dieter Pessel, Heidelberg, DE;
Werner Weinle, Friedelsheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
A process for preparing hydroxyl-containing polymers and, in particular, a process for preparing polytetrahydrofuran with terminal hydroxyl groups from the corresponding acyloxy-containing polymers by transesterification with alcohols is carried out continuously in at least one stirred vessel, with the foam produced in the transesterification being fed tangentially to a cylindrical container, preferably a cyclone separator, at an adequate velocity to destroy the foam. The liquid phase which separates out is recycled through a line to the at least one stirred vessel. This continuous process is preferably carried out in a cascade of stirred vessels, in which each stirred vessel or a subunit of at least two stirred vessels can in each case be coupled to a cylindrical container, preferably in the form of a cyclone separator.