FIELD: 1,2-syndiotactic polybutadiene production.
SUBSTANCE: inventions group relates to a method for producing 1,2-syndiotactic polybutadiene in the presence of a catalytic system containing at least one cobalt complex, including a phosphine ligand selected from highly sterically hindered aromatic phosphines, and to a cobalt complex, including a phosphine ligand. The method for producing 1,2-syndiotactic polybutadiene includes the polymerization of 1,3-butadiene in the presence of a catalytic system containing at least one cobalt complex, including a phosphine ligand and described by the general formula (I)
,
where each R1 is a tert-butyl or neomentyl group, each R2 and R3 is a phenyl group, X1 and X2 are halogen atoms and methylalumoxane, the alumoxane and the cobalt complex being in such a ratio that the molar ratio between the aluminum present in the alumoxane , and cobalt present in the cobalt complex comprising a phosphine ligand and described by the general formula (I) was in the range from 10 to 100, while the method is carried out at a temperature in the range from 0°C to +20°C.
EFFECT: enabling the production of 1,2-syndiotactic polybutadiene having the following characteristics: a 1,2-elemental content of 80% or more, a syndiotactic triad content [(rr)%] of 76% or more, and a melting point of 139°C or more; due to these characteristics, the 1,2-syndiotactic polybutadiene obtained can be used advantageously in various fields such as, for example, the shoe industry, in particular in the production of shoe soles.
5 cl, 22 dwg, 3 tbl, 11 ex
