(Co)polymerising conjugated dienes, esp. butadiene with styrene - with reaction prod. of organometallic cpds. of alkali, alkaline earth and gp. IIIA metal as catalyst

摘要

In the parent patent conjugated dienes are polymerised or are copolymerised with other conjugated dienes or with vinyl-aromatic cpds. in an inert solvent, using as catalyst a reaction prod. from (a) acpd. of formula Me'MR'R2R3R4 Me2(MR'R2R3R4)2, MR'R2R or Me'OMR'R2, (where Me' is an alkali metal, Me2 is an alkaline earth metal M is a metal gp. IIIA, R', R2 and R3 are (ar)alkyl gps. and R4 is an (ar)alkyl gp. or XB, in which X is O, S or N; and B is an (ar)alkyl gp. or MR5R6 in which R5 and R6 are an (ar) alk 1 gp). and (b) is not 1 electron donor contg. is not 1 heteroatom formed among others by reaction prods. of alcohols with an alkali metal. The improvement is that (co) polymerisation is at 50-100 degrees C opt in an inert solvent, using as catalyst a reaction prod. from (a) Me2(MR'R2R3R4)2, with (b) an electron donor of formula R(OCH2CH2)nOMe' or R2NCH2CH2OMe' (where R is an alkyl gp. and n is an integer). The (co)polymers have a high content (up to 92%) of 1,4-trans chains and 4% of 1,2- or 3,4-chains. The inherent viscosity and the 1,4-trans content of the polymers and the rate of polymerisation can be regulated by varying the molar ratio of (a) (b). Tyres and tyre treads produced from the (co)polymers are claimed.