| 摘要 |
<p>Catalyst for the stereospecific polymerization of alpha-olefins of 3 or more carbon atoms comprising an organoaluminum compound and a component prepared from halogen-containing compound of titanium(IV), organic electron donor, and a pretreatment product of components comprising magnesium alcoholate, Group II or IIIA metal alkyl, and optionally, one or more pretreatment modifiers such as a mineral acid or anhydride of sulfur, organometallic chalcogenide derivative of hydrogen sulfide, organic acid or organic acid ester. Preferably, the product obtained from such materials is contacted with liquid Lewis acid and mechanically activated prior to polymerization use.</p> |
