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:
Nov. 16, 1999
Filed:
Jul. 08, 1998
Jean Steininger Clites, North Canton, OH (US);
Howard Allen Colvin, Tallmadge, OH (US);
Daniel Frederick Klemmensen, Tallmadge, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
This invention discloses a process for synthesizing a styrene-butadiene polymer, which is particularly useful for modifying asphalt to improve force ductility, elastic recovery, toughness and tenacity, by a process which comprises the steps of: (1) continuously charging 1,3-butadiene monomer, an organo lithium compound, a polar modifier and an organic solvent into a first polymerization zone, (2) allowing the 1,3-butadiene monomer to polymerize in said first polymerization zone to a conversion of at least about 90 percent to produce a living polymer solution which is comprised of said organic solvent and living polybutadiene chains having a number average molecular weight which is within the range of about 20,000 to about 60,000, (3) continuously withdrawing said living polymer solution from said first reaction zone, (4) continuously charging styrene monomer, divinyl benzene and the living polymer solution being withdrawn from the first polymerization zone into a second polymerization zone, (5) allowing the styrene monomer and divinyl benzene monomer to polymerize in said second polymerization zone to produce a solution of styrene-butadiene polymer having a number average molecular weight which is within the range of about 30,000 to about 85,000 and (6) continuously withdrawing the solution of said styrene-butadiene polymer from the second polymerization zone.