| 摘要 |
A polymerization catalyst for butadiene comprises (1) the reaction product of a conjugated diene selected from butadiene and isoprene with lithium aluminium hydrides, or aluminium hydrides or organoaluminium compounds of the formula RmAlHm, where R is a radical selected from saturated aliphatic, cycloaliphatic, and aromatic radicals, n is an integer of 1 to 3, m is an integer of 0 to 2, and n+m=3, and (2) a compound containing iodine and titanium. The ratio of gram atoms of aluminium in the reaction product to total titanium in the catalyst system is in the range of 3:1 to 30:1. Component (1) is generally prepared by reacting the ingredients at a temperature between 50 DEG and 200 DEG C. for 15 to 200 minutes. Component (2) may be TiI4, TiCl4 and TI4, a titanium halid of the formula TiXa, where X is Cl or Br, and a is an integer of 2 to 4, and an iodine constituent selected from elemental iodine, an inorganic iodide, an iodohydrocarbon, or an organoaluminium iodide of the formula RxAlyIz, where R is an aliphatic, saturated cycloaliphatic or aromatic radical, x and z are integers of 1 to 3, y is an integer of 1 to 2, and x plus z equals 3 times y. The catalyst is used to polymerize butadiene by conventional "low-pressure" techniques. The polybutadiene has at least an 85% cis-1,4-addition structure.
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