The synthesis of an alternating ethylene-p-chlorostyrene copolymer is perfo
rmed in the presence of a homogeneous Ziegler-Natta catalytic system consti
tuted of rac-(isopropylidene)bis( l-indenyl)zirconium bis(dimethylamide) an
d methylaluminoxane. An isotactic arrangement of the p-chlorostyrene units
is observed.