| 摘要 |
PURPOSE:The two-staged polymerization of a conjugated diolefin is carried out in hydrocarbon using an organolithium as an initiator, then the polymers terminated with Li atoms are coupled with a coupling agent to give the titled polymer having a specific molecular weight distribution and good processability. CONSTITUTION:In the polymerization of a conjugated diolefin or a mixture thereof with a vinyl aromatic hydrocarbon using an organolithium compound as an initiator in a hydrocarbon solvent, in the first step, 10-70wt% of the total monomers are polymerized at the maximum temperature of 30-80 deg.C, then the rest of the monomers are added continuously or batchwise to effect the following polymerization at -20-150 deg.C. The resulting polymer having Li atom terminals are coupled to give the objective polymer containing less than 40wt% of bound vinyl aromatic hydrocarbon, 30-90wt% of vinyl bonds in the conjugated olefin parts and less than 30wt% of coupled polymers and having 5-20wt% of the part of less than 100,000 molecular weight according to the measurement of molecular weight distribution by gel-permeation chromatography.
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