Process for polymerizing butadiene with cobalt complex, AlR.sub.3 and CS.sub.2
AssigneeThe Firestone Tire & Rubber Company
InventorAdel Farhan Halasa
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Abstract
1,3-Butadiene is polymerized in the liquid phase in the presence of a catalyst composition comprising: A. A complex of a cobalt salt; B. AlR.sub.3 wherein R is hydrocarbon, and C. CS.sub.2. The complex comprises one of a cobalt salt, preferably CoCl.sub.2, with an organic compound containing nitrogen and oxygen or sulfur, preferably with no more than 2 carbon atoms separating the nitrogen and oxygen or sulfur, and the organometal reducing agent AlR.sub.3, wherein R is a hydrocarbon radical, preferably of no more than 10 carbon atoms. The polybutadiene has a microstructure of at least 80% and generally more than 90% 1,2, is also syndiotactic in character, has a melting point of 190.degree.-227.degree. C, and may be obtained in approximately quantitative yields.
Claims14
A process for the preparation of polybutadiene high in syndiotactic 1,2 structure range of 190.degree.-227.degree. C., which comprises polymerizing 1,3-butadiene in the liquid phase in the presence of a catalyst composition consisting essentially of:
- a. a complex of a cobalt salt selected from the class consisting of halides, carboxylates, carbonate and thiocarboxylates, said complex being formed with a cyclic compound having an amino nitrogen and a keto or thioketo group therein selected from the class consisting of N-methyl-pyrrolidone, pyrrolidone, caprolactam, p-aminoacetophenone, N,N-dimethyl-p-aminoacetophenone, N-methyl-2-aminocyclohexanone, N-methyl-thiopyrrolidone and thiocaprolactam;
- b. a reducing agent having the formula AIR.sub.3, wherein R is a hydrocarbon radical of 1-8 carbon atoms;
- and
- c. CS.sub.2.
Dependencies are inferred from the claim text.