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:
Aug. 07, 2018
Filed:
Sep. 13, 2016
Covestro Llc, Pittsburgh, PA (US);
Covestro Deutschland Ag, Leverkusen, DE;
Rick L. Adkins, Canonsburg, PA (US);
William E. Wood, Hurricane, WV (US);
Edward P. Browne, Cologne, DE;
COVESTRO LLC, Pittsburgh, PA (US);
COVESTRO DEUTSCHLAND AG, Leverkusen, DE;
Abstract
This invention relates to a process for preparing a stable low viscosity polymer polyol having a solids content of at least about 30% by weight. This process comprise free-radically polymerizing one or more base polyols, one or more pre-formed stabilizers, and one or more ethylenically unsaturated monomers in the presence of one or more free-radical polymerization initiators, and one or more polymer control agents; in which the process is restarted after being stopped by (I) restarting the feed of base polyol and the initiator; (II) continuing the base polyol and initiator feed until the total feed amounts to at least 5% of the total reactor volume; and (III) restarting the feed of the ethylenically unsaturated monomers in which the ratio of monomers to total feed is ramped up to its final value over a period of not less than 25% of the reactor residence time. This process is particularly suitable for restarting the process of production after any planned or unplanned reactor shutdown.