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:
Nov. 02, 1993
Filed:
Mar. 01, 1991
Manfred Niessner, Schifferstadt, DE;
Stefan Wickel, Ludwigshafen, DE;
Walter Schneider, Ludwigshafen, DE;
Juergen Beck, Viernheim, DE;
Heinrich Hartmann, Limburgerhof, DE;
Thomas Meyer, Boehl-Iggelheim, DE;
BASF Aktiengesellschaft, Ludwigshafen, DE;
Abstract
Finely divided, water-soluble polymers are prepared by polymerization of water-soluble, monoethylenically unsaturated monomers in not less than 20% strength by weight aqueous solution in the presence of a polymerization initiator in a kneader by a process in which from 0.1 to 10% by weight, based on the total monomers, of a surfactant are used in the polymerization, the polymerization initially being carried out to a conversion of the monomers of not less than 60% in the absence of the surfactant or in the presence of not more than 50% of the amount of surfactant, and the remaining amount of surfactant then being added to the reaction mixture and the polymerization completed. The addition of surfactant causes the polymer gel to disintegrate with formation of fine particles.