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:
Oct. 01, 1991
Filed:
Jan. 19, 1990
Harry R Allcock, State College, PA (US);
Sukky Kwon, Elkhart, IN (US);
The Pennsylvania Research Corporation, University Park, PA (US);
Abstract
Hexachlorocyclotriphosphazene and poly(dichlorophosphazene) react with the sodium salt of ethyl p-hydroxybenzoate to give small molecule cyclic and high polymeric phosphazenes with aryloxy ester side groups; reaction of these compounds with potassium tert-butoxide brings about complete hydrolysis of the ester groups to yielding aqueous media-soluble, carboxylic acid bearing cyclic and high polymeric phosphazenes; the carboxylic acid bearing high polymer formed ionic cross-links when treated in aqueous media with salts of di- or trivalent cations yield hydrogels and membranes. The cross-linked gels were stable in neutral or strongly acidic aqueous media, but the cross-linking process was reversed in basic aqueous solutions of excess monovalent cations.