METHOD OF CIS-1,4-POLYISOPRENE PREPARATION Russian patent published in 2009 - IPC C08F136/08 

FIELD: chemistry.

SUBSTANCE: cis-1,4-polyesopren is obtained by isoprene polymerisation in a solution of isopentane or in the isopentane-isoamylenes mixture at the temperature 20-60°C with isoprene content 10-20 wt %. The reaction is carried out in a presence of catalytical complex which is prepared beforehand during 2 - 24 hrs. by interreaction of neodymium compound in hydrocarbon solvent with alkylating agent, halogen donor and conjugated diene which can be added in any consequence. Mole ratio of neodymium: alkylating agent: halogen donor: conjugated diene is respectively 1:1.8-20:2-3:8-25. Before the mixing with catalyst components the neodymium compound undergoes interreaction with polyatomic alcohol taken in amount of 10-100% mole in relation to neodymium.

EFFECT: enhancing of polyisoprene yield at 12-36 % while maintaining the cis-1,4-repeating units content in polymer on a high level.

2 cl, 10 ex