POLYISOPRENE HAVING A HIGH CONTENT OF 1,2 AND 3,4 STRUCTURAL UNITS, PROCESS FOR PREPARING THEM AND THEIR USE

摘要

1. A process for the preparation of optionally functionalized polyisoprene containing more than 70% of 1,2- and 3,4-structural units by anionic polymerization of isoprene in an inert organic solvent in the presence of an organolithium compound as catalyst and in the presence of an ether as cocatalyst, characterized in that, as catalyst, a monofunctional or bifunctional alkyllithium compound containing alkyl radicals having 1 to 10 C atoms and, as cocatalyst, an ethylene glycol dialkyl ether of the formula R1 -O-CH2 -CH2 -O-R2 , where R1 and R2 are alkyl radicals having different numbers of C atoms, from the group comprising methyl, ethyl, n- and iso-propyl and n-, iso-, sec.- and tert.-butyl, are employed in the ratio 2:1 to 15:1, relative to the number of moles of catalyst, at temperatures of from 0 to 100 degrees C.