| Abstract
| - A series of bis(phenoxyketimine)titanium dichloride complexes were synthesized and evaluatedas catalysts for living, isoselective propylene polymerization upon activation with methylaluminoxane (MAO).Catalysts bearing phenoxyketimine ligands with different substituents at the ortho and para positions ofthe phenolate ring and substituents at the ketimine carbon were investigated. The identity of the ketiminesubstituent had the largest effect on the activity and isoselectivity of propylene polymerization. Complex12/MAO promoted the living, isoselective polymerization of propylene ([m4] = 0.73, α = 0.94). This catalystsystem was used for the synthesis of a number of block copolymers featuring isotactic polypropylenesemicrystalline blocks and poly(ethylene-co-propylene) amorphous blocks. Several triblock samples withvarying block lengths, a pentablock, and a heptablock copolymer were synthesized. Mechanical testinghas revealed that each is elastomeric with elongations at break between ∼790−1000%.
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