METHOD OF PREPARING 1,2-POLYBUTADIENE Russian patent published in 1999 - IPC

FIELD: chemical industry, more particularly synthetic rubber industry, tire, industrial rubber and abrasive industries. SUBSTANCE: described is method of preparing polybutadiene containing preferably vinyl units in hydrocarbon solvent in the presence of organolithium initiator, modifying additive and divinyl benzene. Additive includes diethylene glycol diethyl ether and/or tetrahydrofurfuryl alcohol ether. Process of polymerization of butadiene- 1,3 is carried out in two stages. In first stage n-butyl lithium is added to blend with 10-20 wt % original monomer concentration in amount 10-60 moles per 1 ton of butadiene-1,3, and modifying additive is added at molar ratio to n-butyl lithium within 0.05 to 1.0. Process is carried out at 20-50 C to attain at least 95% monomer conversion; in second stage divinyl benzene is added at molar ratio to n-butyl lithium within 0.1-0.5, and the whole is maintained for 2-80 minutes, and butadiene-1,3 is further added as blend having the same original monomer concentration at weight ratio to original butadiene-1,3 within 1-15, and modifying additive at molar ratio to n-butyl lithium within 0.01-0.3, and process is carried out at 20-80 C to attain at least 95% conversion. Method makes it possible to obtain polybutadiene containing 40-80% of 1 or 2 units and use new modifying additives. EFFECT: more efficient preparation method. 4 ex, 1 tbl