Polypropylenes had been obtained with racemic ethylenebis(indenyl)zirconium dichloride/ methyl aluminoxane (MAO) catalyst from -55 to +80 °C and Al/Zr ratios between 103 and 1.6 X 104. As the polymerization temperature increases, the polymers produced have progressively lower melting transition temperature, lower homosteric pentad sequence population, and higher solubility in low-boiling solvents, indicating frequent stereochemical inversion in monomer enchainment. Polymer fractions separated by solvent extraction are relatively crystalline (crystallinity > 50%) favoring a thermally stable 7-modification. The 13C NMR spectra also showed the presence of tetramethylene unit in acetone-and ether-soluble fractions. In addition, there is tail-to-tail enchainment in PP obtained at a low MAO to Zr ratio. The results indicate variations of degrees of stereochemical and regiochemical control by the rac-Et[Ind]2ZrCl2/MAO catalyst with polymerization temperature and catalyst composition.

Five styrene derivatives with annular substituents (SAs), called CPBE, CHBE, THNE, THBE and META, were successfully synthesized and living anionic polymerization was conducted.

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Perfect syndiospecific polymerization of carbazole-substituted styrene derivatives was achieved using a rare-earth metal catalyst. Also copolymerization of FSt with styrene afforded copolymers with gradient sequence distributions and easily tunable incorporation rate.