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:
Dec. 01, 1998
Filed:
May. 16, 1997
John E Hayes, Gouvieux, FR;
Leah J Langsdorf, West Chester, PA (US);
Bruce H Isaacs, Media, PA (US);
Fred J Armellini, Willow Grove, PA (US);
Arco Chemical Technology, L.P., Greenville, DE (US);
Abstract
A process for activating double metal cyanide catalysts is disclosed. A polyol starter or starter/catalyst mixture is heated under vacuum under conditions effective to achieve improved stripping compared with that which can be achieved through conventional vacuum stripping. Coupling vacuum stripping with inert gas sparging or stripping in the presence of an organic solvent gives a starter/catalyst mixture that activates rapidly in an epoxide polymerization process. Rapid activation makes process start-ups reliable and reduces cycle time. The process gives polyols with lower viscosity, lower polydispersity, and lower unsaturation for better polyurethanes.