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:
Sep. 04, 1995
Filed:
Nov. 29, 1993
Applicant:
Inventor:
James H Collins, Houston, TX (US);
Assignee:
Shell Oil Company, Houston, TX (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C08L / ;
U.S. Cl.
CPC ...
524 59 ; 524 68 ; 524 71 ; 1062811 ;
Abstract
The present invention is an improvement in a process for producing a blend of bitumen and a block copolymer of a vinyl aromatic hydrocarbon and a conjugated diene comprising mixing from 88 to 99.5 weight percent of bitumen with 0.5 to 12 weight percent copolymer at 135.degree. to 250.degree. C., agitating the mixture for at least 30 minutes, adding 0.01 to 2 weight percent sulfur and maintaining the mixture under agitation for at least 30 minutes. The improvement comprises utilizing high shear mixing at a shear rate of at least 10,000 second.sup.-1 to provide said agitation.