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. 07, 1999
Filed:
Oct. 26, 1998
Joseph P Haar, Jr, Wheaton, IL (US);
Robert J Ross, Elmhurst, IL (US);
Donlar Corporation, Bedford Park, IL (US);
Abstract
Disclosed are methods of producing super-absorbing polymeric networks of polyaspartates from crosslinked polysuccinimide. In one preferred aspect, polysuccinimide is first reacted with an organic crosslinking agent, preferably an organic base containing at least two primary amine groups, to form a gelled crosslinked polysuccinimide. The gelled crosslinked polysuccinimide is then base hydrolyzed to a gelled polymeric network of polyaspartate and deswollen with at least one liquid alcohol to a polymeric network of polyaspartate which demonstrates super-absorbing capability in water and in electrolyte solution. Super-absorbing polymeric networks of polyaspartates can also be produced in a single reaction vessel by sequentially crosslinking a polysuccinimide with an organic crosslinking agent in an aqueous reaction medium, optionally containing a mineral acid, and then hydrolyzing the crosslinked polysuccinimide to produce a polymeric network of polyaspartate.