The catalyst DADNi(NCS) 2 (DAD ¼ (ArN¼ ¼C(Me)À ÀC(Me)¼ ¼ArN); Ar ¼ 2,6-C 6 H 3 ), activated by methylaluminoxane, was tested in ethylene polymerization at temperatures above 25 8C and variable Al/Ni ratio. The system was shown to be active even at 80 8C and when supported on silica. However, catalyst activity decreased.The catalyst system was also tested in ethylene and 10-undecen-1-ol copolymerization at different ethylene pressures. The best activities were obtained at low polar monomer concentration (0.017 mol/L), using triisopropylaluminum (Al-i-Pr 3 ) to protect the polar monomer. The incorporation of the comonomer increased with the increase of polar monomer concentration. According to 13 C NMR analyses, all the resulting polyethylenes were highly branched and the polar monomer incorporation decreased as ethylene pressure increased. V V C 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5199-5208, 2007

Ethylene‐propylene‐1‐hexene terpolymers were obtained using three metallocenic systems: Cp2ZrCl2, Cp2ZrCl2 directly supported on silica (Cp2ZrCl2/SiO2) and Cp2ZrCl2 supported on MAO (methylaluminoxane)‐modified silica (Cp2ZrCl2/MAO/SiO2). The results were compared with those obtained with rac‐Et[Ind]2ZrCl2. The best activities were obtained with the Cp2ZrCl2 in the homogeneous form, but the system Cp2ZrCl2/MAO/SiO2 afforded also good results. Those systems showed to be able to incorporate enough comonomers, in a randomic way, to give terpolymers with an elastomeric behaviour.

An α‐iminocarboxamide nickel complex was activated by trimethylaluminum (TMA) and used in the polymerization of ethylene and its copolymerization with 10‐undecen‐1‐ol. The best activity was observed upon activation with 9 equiv of TMA at a temperature of 26 °C. NMR spectroscopic studies did not show 10‐undecen‐1‐ol incorporation. However, FTIR analyses suggest the incorporation of a very small amount of comonomer, which affects the glass transition temperature, the degree of branching, and the mechanical properties of the materials. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 54–59, 2008

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