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:
Apr. 11, 1995
Filed:
Jul. 29, 1993
Applicant:
Inventor:
Miguel Prado, Sugarland, TX (US);
Assignee:
Shell Oil Company, Houston, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08F / ;
U.S. Cl.
CPC ...
525285 ; 525301 ; 525338 ;
Abstract
A process for improving the color of selectively hydrogenated block copolymers modified with acid compound or derivatives thereof which comprises: (a) anionically polymerizing at least one conjugated diene, and, optionally, at least one vinyl aromatic hydrocarbon, to produce a block copolymer, (b) selectively hydrogenating the block copolymer, (c) subjecting the block copolymer to an acid wash, (d) subjecting the acid washed block copolymer to high efficiency water washing at a residence time of not less than 50 minutes and a water to polymer cement weight ratio of more than 0.2, and (e) grafting an acid compound or a derivative thereof onto the block copolymer.