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. 16, 1994
Filed:
Apr. 21, 1993
Applicant:
Inventors:
Assignee:
ISP Investments Inc., Wilmington, DE (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ; C08F / ;
U.S. Cl.
CPC ...
526210 ; 526209 ; 526264 ;
Abstract
A process for making polyvinylpyrrolidone (PVP) K-90 having a polydispersity of less than 6, preferably less than 5, and most preferably, less than 4, which comprises polymerizing vinylpyrrolidone monomer by free radical solution polymerization, in water, in the presence of polyethylene glycol (PEG) having a molecular weight of about 300 as a chain transfer agent. The product is an aqueous solution of 15-25% PVP K-90, preferably 20%, 15-30% PEG, preferably 25%, and 45-70% water, preferably 55%, by weight of the solution.