A series of monodisperse polynorbornene (PNB) chains bearing different contents of aryloxide ligands at their side chain were synthesized by Grubbs ring-opening metathesis copolymerization between norbornene and 2-aryloxonorbornene. These PNB chains were employed as a soluble support for grafting half-titanocene complexes to afford structurally well-defined supported catalysts, where a pre-defined number of Ti centres was confined in a nano-sized random coil of PNB chains. Extensive investigation in ethylene polymerization revealed unique catalytic features of these soluble polymer-supported catalysts, represented by a synergistic activity enhancement among multiple active centres confined in a random coil. The well-defined nature of these novel polymer-supported catalysts is powerful in studying interactions between active centres and supports as well as among active centres themselves in catalysis.

通过在降冰片烯和2-芳基氧还体降冰片烯之间开环易位共聚反应，合成了一系列在侧链上带有不同含量的芳氧化物配体的单分散聚降冰片烯（PNB）链。这些PNB链用作接枝半钛茂金属配合物的可溶性载体，以提供结构明确的负载型催化剂，其中，预先定义的Ti中心数限制在PNB链的纳米级无规卷曲中。在乙烯聚合反应中的广泛研究表明，这些可溶性聚合物负载的催化剂具有独特的催化特性，以受限于无规卷曲的多个活性中心之间的协同活性增强为代表。