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:
Mar. 04, 2003
Filed:
Dec. 13, 2001
Rick L. Adkins, New Martinsville, WV (US);
William E. Miller, St. Clairsville, OH (US);
Bayer Corporation, Pittsburgh, PA (US);
Abstract
This invention relates to a process for forming an allophanate-modified polymethylene poly(phenylisocyanate) comprising the steps of reacting a small amount of epoxide, along with alcohol, to polymethylene poly(phenylisocyanate) (PMDI) to form an intermediate, which is converted to allophanate upon addition of a metal divalent catalyst. This invention also relates to a process for forming an allophanate-modified PMDI comprising the steps of adding a small amount of epoxide, to PMDI to form an intermediate, which is converted to allophanate upon addition of an alcohol and a metal divalent catalyst. Both processes according to the invention of preparing allophanate-modified PMDI use mild conditions and low catalyst levels to yield viscosity stable products.