Accessing Siloxane Functionalized Polynorbornenes via Vinyl-Addition Polymerization for CO2 Separation Membranes

The vinyl addition polymerization of norbornyl-based monomers bearing polar functional groups is often problematic, leading to low molecular weight polymers in poor yield. Herein, we provide proof-of-principle evidence that addition-type homopolymers of siloxane substituted norbornyl-based monomers may be readily synthesized using the catalyst trans-[Ni(C6F5)(2)(SbPh3)(2)]. Polymerizations using this catalyst reached moderate to high conversion in just 5 min of polymerization and produced siloxane-substituted polymers with molecular weights exceeding 100 kg/mol. These polymers showed excellent thermal stability (T-d >= 362 degrees C) and were cast into membranes that displayed high CO2 permeability and enhanced CO2/N-2 selectivity as compared to related materials.