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:
Sep. 23, 2003
Filed:
Nov. 26, 2002
Yoon Tae Kwak, Woodcliff, NJ (US);
Stephen L. Kopolow, Plainsboro, NJ (US);
Alan J. Carlin, Wayne, NJ (US);
ISP Investments Inc., Wilmington, DE (US);
Abstract
A process for making a solution of a copolymer of maleic anhydride (MA) and methyl vinyl ether (MVE) monomers the specific viscosity (SV) of the product being about 2.5-6, preferably 3-5, indicating a weight average molecular weight of substantially above one million, preferably above 1.5 million and a solids content of about 20-45%, preferably 30-40, in isopropyl acetate (IPAc), solvent includes the steps of (a) precharging part of MVE in IPAc into a reactor heated to about 50-90° C., and then (b) feeding (i) a solution of MA in IPAc, (ii) the rest of MVE, at a mole ratio of MA:MVE of 1:≧1.5 to 1:<3, preferably 1:2.4, and (iii) a free radical initiator dissolved in IPAc, in an amount of 0.02-0.3%, preferably 0.05-0.2%, based on total monomers, into the reactor over time. Powders of such MA/MVE copolymers are made by removing the solvent from the solution.