| 摘要 |
A multicomponent preformed catalytic system based at least:
on isoprene,on a rare earth metal salt of an organic phosphoric acid or of a carboxylic acid;on a saturated or unsaturated inert hydrocarbon solvent, the boiling point of which is below 40° C. at atmospheric pressure;on an alkylating agent consisting of a specific trialkylaluminium; andon a halogen donor consisting of an alkylaluminium halide; this catalytic system comprising the rare earth metal in a concentration greater than or equal to 0.005 mol/l.;The catalytic system makes possible polymerizing isoprene, with a good catalytic activity, in solution in a volatile hydrocarbon solvent while benefiting from the economic advantage linked to a volatile solvent process, which is also a subject of the invention. The diene elastomers obtained have a high content of cis-1,4 linkages. |
| 主权项 |
1. A multicomponent catalytic system based at least:
on isoprene, as preforming monomer, on a rare earth metal salt of an organic phosphoric acid, or on a rare earth metal salt of a carboxylic acid; on a saturated or unsaturated inert hydrocarbon solvent, the boiling point of which is below 40° C. at atmospheric pressure; on an alkylating agent consisting of a trialkylaluminium of formula AlR3, in which R represents an alkyl radical preferably having from 1 to 10 carbon atoms, selected from trimethylaluminium, triethylaluminium, tri-n-propylaluminium, triisopropylaluminium, tri-n-butylaluminium, tri-t-butylaluminium, tri-n-pentylaluminium, tri-n-hexylaluminium, tri-n-octylaluminium, tricyclohexylaluminium; and on a halogen donor consisting of an alkylaluminium halide, the alkyl radical preferably having from 1 to 8 atoms; wherein this catalytic system comprises the rare earth metal in a concentration greater than or equal to 0.005 mol/l. |
