Living Ziegler-Natta Polymerization
Several reported methods exist that introduce livingness in Ziegler-Natta polymerization. The monomer in this type of polymerization (a subset of coordination polymerization) is an alpha-olefin and the active site contains an alkyl to metal bond. Chain growth is based on the Cossee-Arlman mechanism. An early method (Doi, 1979) describes propene polymerization in toluene at −50°C using diethylaluminium chloride and a vanadium catalyst for example V(acac)3 to syndiotactic polypropylene with a polydispersity index of 1.05 to 1.4. Another living system as described by McConville in 1996 is based on titanium using 1-hexene, TiMe2 and tris(pentafluorophenyl)boron
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