Synthesis Characterization of Polyamide Metallodendrimers and their Catalytic Activities in Ethylene Oligomerization

摘要

Abstract Nickel complexes with aromatic amine terminated first generation (G1) and second generation (G2) polyamide dendrimers {POA-(NH₂)_n (n = 6 or 12, POM = Polyamide)} were synthesized. All the synthesized dendrimers and metallodendrimers were characterized by elemental and spectral analysis. These novel dendritic complexes were evaluated as catalyst precursors in the oligomerization of ethylene, using methylaluminoxane (MAO) as an activator at two different pressure and different Al/M (M = Zn) ratio. In the case of 1 atm pressure of ethylene, and 500:1 and 1,000:1 Al/Ni molar ratio, for C ₁ and C ₂ respectively display higher catalytic activity towards ethylene polymerization. Oligomerization using the generation 1 dendrimer complex, C ₁ yields short chain oligomers whereas those obtained from the generation 2 dendrimer catalyst, C ₂ resulted in longer chain products with molecular weights up to 9.54 × 104 and 9.86 × 104 g/mol at 1 and 5 atm respectively.