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:
Feb. 19, 2013
Filed:
May. 31, 2011
Dale Lee Handlin, Jr., Houston, TX (US);
Scott Russell Trenor, Houston, TX (US);
Gregory Paul Dado, Chicago, IL (US);
Dale Lee Handlin, Jr., Houston, TX (US);
Scott Russell Trenor, Houston, TX (US);
Gregory Paul Dado, Chicago, IL (US);
Kraton Polymers US LLC, Houston, TX (US);
Abstract
The present invention relates to an improved method for making sulfonated block copolymers and to methods for making membranes from such block copolymers. In particular, the present invention relates to an improved method for making sulfonated block copolymers having at least two polymer end blocks that are resistant to sulfonation and at least one polymer interior block that is susceptible to sulfonation where the sulfonation agent is Cto Cacyl sulfate. In the improved process the residual carboxylic acid formed from the Cto Cacyl sulfate is converted to Cto Calkyl esters by contacting the residual carboxylic acid with at least a 0.9:1 molar ratio of a Cto Calcohol to residual carboxylic acid, resulting in an improved sulfonated block copolymer solution. The present invention further relates to the use of such sulfonated block copolymer solutions to prepare various membranes and other articles.