Characterization of polypropylenes prepared with bis‐indenyl type metallocene and MgCl2‐supported TiCl4 catalyst systems

The homo‐polypropylene: m‐PP, prepared with rac‐Me₂Si[2‐n‐Pr‐4‐(9‐Phenanthryl)‐Ind]₂ZrCl₂, showed 99.6% of [mmmm] and 162.8°C of melting temperature (Tm). This polymer was compared by TREF analysis with the homo‐polypropylene: Ti‐PP, which was produced by our latest MgCl₂‐supported TiCl₄ catalyst system and showed 99.0% of [mmmm] and 165.7°C of Tm. It was indicated that m‐PP has narrower stereoregurality distribution than Ti‐PP and Tm of the fraction eluted from m‐PP at the highest temperature range is 163.6°C, while that from Ti‐PP reaches to 167.3°C. The characters and advantages of each polymer are discussed on the basis of these results. In addition, an advantage of this metallocene was made clear by characterization of polypropylenes copolymerized with ethylene.