GB1438718A - Isomerisation of lower polymers of butadiene - Google Patents

Abstract

1438718 Isomerizing butadiene polymers NIPPON OIL CO Ltd 24 Aug 1973 [25 Aug 1972 28 Sept 1972] 40330/73 Heading C3P Lower polymers of butadiene and copolymers of butadiene with other conjugated dienes or vinyl aromatic monomers, said polymers and copolymers being liquid or semi-solid at room temperature and having a M.W. of 300- 10,000, are isomerized to give products containing conjugated double bonds by contact at 0-200‹ C. with a catalyst comprising (1) an organic alkali metal compound and (2) a diamine compound of formula in which n is 2 or 3, and the Rs each represent hydrogen or a C 1-20 organic radical (including substituted radicals) optionally any two of R 1 to R 4 being bonded together to form a cyclic structure. Alternatively, isomerization may be effected at 0-200‹ C. by adding a diamine compound as defined above to a polymerization mixture of monomers defined above, the polymerization having been effected in the presence of an alkali metal or organic alkali metal compound as catalyst. Both procedures are illustrated in the examples, the polymer being polybutadiene or butadiene/styrene copolymer of various stereo structures; the (1) component of the catalyst being, for the first procedure, benzyl sodium, phenyl sodium, amyl sodium, butyl lithium or phenyl potassium, and, for the alternative procedure, benzyl sodium, or orthoterphenyl/sodium complex, butyl lithium or metallic sodium; and the diamine compound (2) being ethylene diamine, tetramethylethylene diamine, tetraethylethylene diamine, diethylene triamine, triethylene diamine, and certain of these amines containing additional methyl substituents. Uses.-Quick-dry paint vehicles, moulded articles, intermediates for further reaction.