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This work reports the preparation of a hydroxyl terminated polystyrene-<i>b</i>-polybutadiene-<i>b</i>-polystyrene triblock copolymer (SBS) with high cis-1, 4 content via a novel nickel catalyst, [&#951;³-Ni(CH₂CHCHCH₂OOCH₃)][BPh^F₄]. FT-IR, ¹H-NMR, and ¹³C NMR indicated that the polybutadiene segment of the copolymer contains greater than 90% cis-1, 4 structure, indicating achievement of the objective. Toward the functionalization goal, a hydroxyl group was successfully introduced at the end of the triblock copolymer (HO&#8211;SBS&#8211;OH). The results of gel permeation chromatography (GPC) revealed that the polymer is indeed a triblock copolymer, with no traces of homopolymer. Differential scanning calorimetry (DSC) showed that HO&#8211;SBS&#8211;OH synthesized using the novel catalyst had a lower glass transition temperature (<i>T_g</i>) than HO&#8211;SBS&#8211;OH synthesized with an alkyl lithium catalyst. Therefore, the polymer synthesized via the novel catalyst contains high cis-1,4 content and displays excellent low-temperature mechanical properties.