| 摘要 |
PURPOSE: A method for controlling branches of polybutadiene having high cis-1,4 content is provided to prevent big changes in molecular weight and physical properties including processability of rubber, flowability at a low temperature and tensile strength. CONSTITUTION: In order to control branches of polybutadiene having a high cis-1,4 content, 1,3-butadiene and Ziegler-Natta catalyst are reacted first to prepare the polybutadiene having a high cis-1,4 content, using organic nickel compounds, boron fluoride complex compounds, alkyl aluminum and aluminoc acid as the Ziegler-Natta catalyst. Then, the reaction takes place between alkyl aluminum and aluminoc acid to control branches in polybutadiene, alkyl aluminum having formula 1 (wherein, R1, R2 and R3 are C1-C10 alkyl, cyclo alkyl, aryl, arylalkyl, alkoxy, or hydrogen, respectively) and aluminoc acid having formula 2 (wherein R4 is methyl and n is an integer from 10 to 20). |
