| 摘要 |
TECHNIQUE FOR REDUCING THE MOLECULAR WEIGHT AND BROADENING THE MOLECULAR WEIGHT DISTRIBUTION OF HIGH CIS-1,4-POLYBUTADIENE High cis-1,4-polybutadiene can be synthesized by polymerizing 1,3-butadiene monomer with a three component nickel catalyst system containing (a) an organonickel compound, (b) an organoaluminum compound, and (c) a fluorine containing compound. However, the molecular weight of the high cis-1,4-polybutadiene prepared is typically too high to be utilized as a non-oil extended rubber. This invention is based upon the discovery that halogenated phenols act to reduce the molecular weight and to increase the molecular weight distribution of high cis-1,4-polybutadiene prepared with such nickel based catalyst systems. The use of halogenated phenols as modifiers in such polymerizations does not change the microstructure of the high cis-1,4-polybutadiene produced. Accordingly, the present invention specifically discloses a process for producing high cis-1,4-polybutadiene having a reduced molecular weight and broad molecular weight distribution which comprises polymerizing 1,3-butadiene in the presence of (a) an organonickel compound, (b) an organoaluminum compound, (c) a fluorine containing compound, and (d) a halogenated phenol.
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