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. 09, 2003
Filed:
Oct. 17, 2002
Applicant:
Inventors:
Beth M. Steinmetz, Bryn Mawr, PA (US);
Manish K. Nandi, Malvern, PA (US);
Assignee:
Arco Chemical Technology, L.P., Greenville, DE (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08L 5/500 ;
U.S. Cl.
CPC ...
C08L 5/500 ;
Abstract
A process for making crosslinked polyvinylpyrrolidone (PVP-P) is disclosed. Crosslinker generation, followed by polymerization of NVP, gives a polymer containing up to 4 wt. % of residual NVP. An aqueous mixture of the polymer is then heated in the presence of a protic acid at pH<4 to eliminate NVP. Finally, the PVP-P is neutralized with aqueous alkali metal hydroxide. The process generates a reduced volume of low-toxicity aqueous waste (<20 L/kg PVP-P) and gives PVP-P that meets important product specifications.