RUBBER COMPOUND FOR TIRE TREAD AND METHOD FOR THE PREPARATION THEREOF

摘要

The invention relates to a rubber cross-linked or crosslinkable compound which contains a diene elastomer having more than 15 % by weight of cyclic vinyl units higher than 15 % and is used for producing a tire tread. Said tire tread and tire casing incorporating it are also disclosed. The inventive compound comprises a diene linear or branched elastomer made of at least one type of conjugated diene and a reinforcing filler and having more than 15 % by weight of cyclic vinyl groups and a mean molecular mass up to 30 000-350 000 g/mol. Said elastomer is produced by anionic polymerisation of one or several conjugated diene-containing monomers, including a reaction of one or several monomers in a hydrocarbon solvent with a catalytic system containing an organolithic initiator and a polar agent having a plurality of hetero-atoms. Said reaction is carried out either in step-wise manner at a molar ratio (molar agent/initiator) higher than 8 or continuously at a molar ratio (molar agent/initiator) equal to or higher than 3.