Journal of Polymer Science Part A: Polymer Chemistry, Vol.37, No.14, 2471-2480, 1999
Polymerization with TMA-protected polar vinyl comonomers. II. Catalyzed by nickel complexes containing alpha-diimine-type ligands
alpha-Diimine Ni complexes (7, 8) were used as catalyst precursors with MAO in co- and terpolymerization of ethylene/propylene/alpha-olefins with OH and COOH functional groups. Trimethylaluminium was used to protect the functional group of polar monomers. The presence of 5-hexen-1-ol seems to have no effect on the polymerization rate at all for the N,N'-bis(2,6-diisopropylphenyl) derivative 8 but caused activity decreases of about fivefold in copolymerization and around two times in terpolymerization for the N,N-dimesityl derivative 7. The effect levels off at higher polar comonomer concentration. This system, (7)/MAO, also incorporates well both 10-undecen-1-ol and 10-undecen-1-oic acid. The activities obtained with these alpha-diimine Ni complexes in co- and terpolymerization are three to twenty times higher than those obtained with group 4 Cp based complexes especially at concentrations of polar monomer in the feed higher than 80 mM.
Keywords:co- and terpolymerization;alpha-diimine Ni complexes;hydroxy-and carboxy- co- and termonomers