Process for producing conjugated diolefin polymer with reduced cold flow
Abstract
Abstract A process for producing a homopolymer or copolymer of a conjugated diolefin by polymerizing a conjugated diolefin alone or copolymerizing a conjugated diolefin with a vinyl aromatic hydrocarbon in the presence of a lithium-type initiator in a hydrocarbon solvent, characterized in that the quantity of said initiator required for the polymerization is divided into two portions, A and B, in a molar ratio of A : B 1 : 3 to 15, and said portion A is added at the outset to initiate the polymerization, and when the conversion to polymer has reached 20 to 60 percent by weight said portion B is added to the polymerization system to carry out the polymerization until it is substantially completed. The polymer obtained by the present process retains the desirable properties which a conventional conjugated diolefin polymer has, and is, in addition, characterized by reduced cold flow.
Inventors
- 👤 Koei Komatsu
- 👤 Eitaro Okuya
- 👤 Katsuyoshi Tomioka
- 👤 Masato Sakai
- 👤 Shigeki Hayashi
- 👤 Hidetoshi Yasunaga
- 👤 Akira Kogure
Bibliographic Details
Claims Analysis
Total Claims: 12References Cited (Backward Citations)
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| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
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