| 摘要 |
Rubbery polybutadiene containing at least 85% cis 1,4 addition is obtained by contacting 1,3-butadiene under polymerization conditions with a catalytic amount of a catalyst selected from the group consisting of (1) a catalyst which is formed on mixing an organometallic compound having the formula RnM where R is an aryl, aralkyl, alkaryl, cycloalkyl, alkylcycloalkyl or cycloalkylalkyl radical, M is zinc, mercury or aluminium and n is an integer equal to the valence of M, and titanium tetraiodide, (2) a catalyst which is formed on mixing an organometallic compound having the formula R3Al where R is as above, p titanium tetraiodide and titanium tetrachloride, and (3) a catalyst which is formed on mixing an organometallic compound of formula R3Al where R is as above, a compound TiXm where X is chlorine or bromine and m is an integer from 2 to 4 inclusive, and iodine. Lists of specific catalyst systems are given. The polymerization is usually carried out in the presence of a diluent, e.g. paraffins, aromatic hydrocarbons and cycloparaffins, and the polymerization temperature may vary, for example, from -100 DEG to 250 DEG F. The polymerization process may be carried out batchwise or continuously and in the former process on completion of the polymerization reaction, the total reaction mixture is treated to inactivate the catalyst and recover the polymer, e.g. the polymer can be recovered by steam-stripping the diluent from the polymer or an alcohol can be added to the polymer mixture. An antioxidant, e.g. phenyl-beta-naphthylamine, may be added to the polymer solution prior to the recovery of the polymer. In Example 1, the catalyst is formed by mixing triphenyl aluminium and titanium tetraiodide and in Example 2, diphenyl zinc is mixed with titanium tetraiodide.
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