Butadiene polymerization with a cobalt salt-diisobutylaluminum chloride-water catalytic system at low temperature

The solubility of polybutadiene formed in a cobalt naphthenate-diisobutylaluminum chloride-water catalytic system was studied as a function of the temperature of storage of the water-toluene mixture, which was varied in a +20... -78°C interval. It is demonstrated that stereoregular polybutadiene, containing 95-97% 1,4-cis-units and virtually completely soluble in toluene, can be obtained in the absence of organic electron-donating compounds. l H NMR spectra show that the intensity of the signal from water protons dissolved in deuterated toluene changes with decreasing temperature. It is suggested that water associates may form that affect secondary processes of the cationic type in the polymer chains. Conditions were selected for the gel-free polybutadiene synthesis, and the effect of the process parameters on the activity of cobalt naphthenate-diisobutylaluminum chloride-water catalytic system was studied.