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:
Oct. 24, 2000
Filed:
Jun. 15, 1999
Roman Loza, Dublin, OH (US);
Laurence G Dammann, Powell, OH (US);
Roger E Hayner, Hebron, KY (US);
Patricia K Doolin, Ashland, KY (US);
Marathon Ashland Petroleum LLC, , US;
Ashland Inc., , US;
Abstract
A method is provided for improving high temperature performance grade properties of unblown asphalt by i) heating an asphalt cement to 200.degree. F. to 500.degree. F. (93.degree. C. to 260.degree. C.), ii) adding 0.1 wt. % to 10 wt. % ethylene-vinyl acetate copolymer based on weight of said asphalt cement to the heated asphalt cement, iii) adding 0.05 wt. % to 1.0 wt. % phosphorus-containing acid, e.g., polyphosphoric acid, based on weight of said asphalt cement and iv) mixing the resulting blend, thereby providing an unblown asphalt composition of greater useful temperature index (UTI). The invention further relates to asphalt compositions thus made and paving compositions containing these asphalt compositions.