Due to chain transfer events being competitive with chain growth, ethylene polymerization by P,O-chelated Ni(II) complexes usually affords low molecular weight polymers or oligomers. We now show that appropriately bulky substituted phosphinophenolato Ni(II) can polymerize in a living fashion, virtually devoid of chain transfer. Aqueous polymerizations with microemulsions of [κ²-P,O-2-(2-(2′,6′-(MeO)₂C₆H₃)C₆H₄)(Ph)P-6-(3′,5′-(CF₃)₂C₆H₃)C₆H₃O-NiMe(pyridine)] (3) at 30 °C yield polyethylenes with narrow molecular weight distributions (M_w/M_n 1.02 to 1.34) and ultrahigh molecular weights (up to 2 × 10⁶) in the form of aqueous nanoparticle dispersions. Catalyst stability and activity are maintained up to 70 °C in water.

中文翻译：

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Ni(II) Phosphinophenolato 催化剂对乙烯的活性水微乳液聚合

由于链转移事件与链增长竞争，通过 P,O 螯合的 Ni(II) 配合物进行的乙烯聚合通常提供低分子量聚合物或低聚物。我们现在表明，适当庞大的取代的膦酰苯酚 Ni(II) 可以以活性方式聚合，几乎没有链转移。[κ ² - P,O -2-(2-(2',6'-(MeO) ₂ C ₆ H ₃ )C ₆ H ₄ )(Ph)P-6-(3', 5'-(CF ₃ ) ₂ C ₆ H ₃ )C ₆ H ₃ O-NiMe(吡啶)] ( 3) 在 30 °C下以水性纳米粒子分散体的形式生产具有窄分子量分布 ( M _w / M _n 1.02 至 1.34) 和超高分子量 (高达 2 × 10 ^{6 ) 的聚乙烯。}催化剂的稳定性和活性在水中可保持高达 70 °C。