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:
Jan. 27, 1976
Filed:
Aug. 31, 1973
Shotaro Sugiura, Ichihara, JA;
Tetsuro Matsuura, Ichihara, JA;
Haruo Ueno, Ichihara, JA;
Minoru Kono, Ichihara, JA;
Hideo Ishikawa, Ichihara, JA;
Thunehiko Tokutomi, Ichihara, JA;
UBE Industries, Ltd., , JA;
Abstract
A process for producing a polybutadiene is provided wherein, first, 1,3-butadiene is polymerized in the presence of a particular cis-1,4-polymerization catalyst and subsequently, the polymerization is continued in the presence of a particular 1,2-polymerization catalyst. The resulting polybutadiene is characterized as containing 2 to 40% of the 1,2-structure, the melting point of the 1,2-structure portion being 110.degree. to 215.degree.C, and containing 60 to 98% of the cis-1,4-structure and having an intrinsic viscosity [.eta.] of 0.9 to 8 in tetraline at 135.degree.C. A vulcanized product of the polybutadiene is characterized as possessing improved tear strength, flex-crack resistance and tensile strength.