The grafting of syndiotactic polystyrene with branched oligoethene was achieved with [Ni(π‐methallyl)(Br)]2/AlCl3 as a catalyst. The molar ratio of AlCl3 to Ni(II) is important, and an efficient reaction occurs only with a large excess of AlCl3. The grafted polymers were characterized by NMR, wide‐angle X‐ray diffraction, and differential scanning calorimetry. The predominant grafts were sec‐butyl groups. No melting point was observed for highly grafted polymers, and X‐ray diffraction studies indicated that these materials were completely amorphous. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 446–451, 2001