Addition polymerization of 5-vinyl-2-norbornene and 5-ethylidene-2-norbornene

Herein we described addition polymerization of 5-ethylidene-2-norbornene and 5-vinyl-2-norbornene in the presence of N-heterocyclic carbene Pd-complexes. After activation with B- or/and Al-organic compounds, these complexes were found to be selective and highly active catalysts for polymerization of these bifunctional norbornenes. The studied catalytic systems were active even at very high monomer/Pd ratios (up to 250 000/1) and their catalytic activity was in the range of 5·106-3·107 gpolymer/(molPd·h). Some interesting relationships between the structure of Pd-complexes and the catalyst activity in polymerization were found. In the presence of these complexes, amorphous, glassy and soluble polynorbronenes containing side alkenyl groups were prepared and characterized by means of IR and NMR spectroscopy.Herein we described addition polymerization of 5-ethylidene-2-norbornene and 5-vinyl-2-norbornene in the presence of N-heterocyclic carbene Pd-complexes. After activation with B- or/and Al-organic compounds, these complexes were found to be selective and highly active catalysts for polymerization of these bifunctional norbornenes. The studied catalytic systems were active even at very high monomer/Pd ratios (up to 250 000/1) and their catalytic activity was in the range of 5·106-3·107 gpolymer/(molPd·h). Some interesting relationships between the structure of Pd-complexes and the catalyst activity in polymerization were found. In the presence of these complexes, amorphous, glassy and soluble polynorbronenes containing side alkenyl groups were prepared and characterized by means of IR and NMR spectroscopy.