Reactive silica in epoxidized polybutadiener

A rubber composition that is based upon a cross-linkable elastomer composition, the cross-linkable elastomer composition comprising, per 100 parts by weight of rubber (phr):

• between 70 phr and 100 phr of an epoxidized rubber component selected from an epoxidized polybutadiene rubber (eBR), an epoxidized styrene-butadiene rubber (eSBR), or combinations thereof, wherein the epoxidized rubber component has a Tg of between −80° C. and −110° C. and an epoxy-function content of between 1 mol % and 25 mol %;
• between 30 phr and 150 phr of a plasticizing resin;
• a quickly reactive silica that provides a macro dispersion Z-value of at least 50 in a defined rubber composition;
• and
• a coupling agent corresponding to
• Z-A-Sz-A-Z
• wherein x is an integer between 2 and 8, A is a divalent hydrocarbon radical and Z corresponds to one of the following:
• wherein R1 radicals are the same or different and are a C1-C18 alkyl, C5-C18 cycloalkyl or C6-C18 aryl group, R2 radicals are the same or different and are C1-C18 alkoxyl or C5-C18 cycloalkoxyl group and wherein R2 radicals are not a hydroxyl radical.