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. 29, 2016
Filed:
Dec. 21, 2010
Joseph Petronella Friederichs, Wessem, NL;
Jacobus Adriaan Antonius Vermeulen, Born, NL;
Marco Marcus Matheus Driessen, Maasbracht, NL;
Joseph Petronella Friederichs, Wessem, NL;
Jacobus Adriaan Antonius Vermeulen, Born, NL;
Marco Marcus Matheus Driessen, Maasbracht, NL;
DSM ASSETS B.V., Heerlen, NL;
Abstract
There is described a process for producing a gel free hyperbranched polyamide polymer having primary amino groups (useful as a crosslinker). The process comprises the step of reacting at least one diamine and at least one unsaturated diester in a molar ratio of diamine to diester greater than 1 but less than 3 (preferably 2.1 to 2.9); to form the polyamide in a two stage reaction Michael addition and then amidation. The diamine in kept in excess with at least 5% of water by total weight of the diamine and diester, a reaction temperature less than the boiling point of the diamine; and is held under reduced pressure (30 mbar to 1 atms). Gelation does not occur even after substantially all ethylenic (—C═C—) double bonds; and >95% ester [—C(O)═O] groups have reacted. This violates the Flory rules which predict a gel would form based on the number of functional groups present and their degree of conversion.