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:
Mar. 19, 1991
Filed:
Nov. 20, 1989
Reinhard Stober, Hasselroth, DE;
Dietmar Bischoff, Alzenau-Michelbach, DE;
Ellen Kohn, Grossaitigen, DE;
Degussa Aktiengesellschaft, Frankfurt, DE;
Abstract
A process for the dry cationization of polyvinyl alcohol (PVA) by reaction of alkylidene epoxides with PVA in alkaline medium in the presence of water, in which the reaction mixture contains 11 to 30 weight % of water, based on its total amount, and 1 to 4 weight % of an alkali metal or alkaline earth metal hydroxide or alkaline earth metal oxide, based on the quantity of PVA. As the cationizing agent there are used alkylidene epoxides or their mixtures having the general formula: ##STR1## wherein n=1, 2 or, 3, R.sup.1, R.sup.2 and R.sup.3 represent the same or different alkyl residues having 1 to 18 carbon atoms or R.sup.1 represents the benzyl or --C.sub.2 H.sub.4 OH, and X.sup.- denotes chloride, bromide, sulfate or acetate. Instead of alkylidene epoxides, the corresponding halohydrins, e.g. chlorohydrin or bromohydrin, can be used.