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. 22, 2022
Filed:
Jun. 26, 2020
Kraton Polymers Llc, Houston, TX (US);
John E Flood, Houston, TX (US);
Xavier Muyldermans, Mont St. Guibert, BE;
Kraton Polymers LLC, Houston, TX (US);
Abstract
A selectively hydrogenated block copolymer of general formula S-E-S, (S-E)X, or mixtures thereof is disclosed, where n has a value of 2-6, and X is a coupling agent residue. Before hydrogenation, S is a polystyrene block having a molecular weight of 4,400-5,600 g/mol, and E and E1 are polydiene blocks having molecular weights of 18,000-36,000 g/mol and 9,000 to 18,000 g/mol, respectively, selected from polybutadiene, polyisoprene and mixtures thereof, and having a total vinyl content of 60-85 mol %. After hydrogenation, the block copolymer has 0-10 percent of styrene double bonds reduced and at least 80 percent of conjugated diene double bonds reduced. The block copolymer has a solution viscosity of less than 80 centipoise (cP); a polystyrene content of 25-40 wt. % and up to 50 wt. % of diblock units of general formula S-E or S-E.