Pneumatic rubber tire having at least one component of a
polybutadiene-rich rubber composition comprised of a blend of a
continuous phase of a specialized cis 1,4-polybutadiene rubber and a
dispersed phase comprised of a composite of styrene/butadiene elastomer
which contains a dispersion of at least partially exfoliated,
intercalated, clay platelets, wherein said cis 1,4-polybutadiene rubber
and styrene/butadiene elastomer have spatially defined glass transition
temperatures, wherein said blend contains amorphous silica and carbon
black reinforcement. Such tire component may be, for example, a
circumferential tread having a running surface intended to be
ground-contacting or a sidewall insert.