Modification effect of spherical zirconia with SiCl4 as a support of methylaluminoxane for heterogeneous single-site catalyst

• Published in: European polymer journal 2013-12, Vol.49 (12), p.4195-4200
• Main Authors: Jantasee, Sasiradee, Jongsomjit, Bunjerd, Yano, Haruki, Shiono, Takeshi
• Format: Article
• Language: English
• Subjects: Applied sciences; Copolymerization; Exact sciences and technology; Living polymerization; Methylaluminoxane; Organic polymers; Physicochemistry of polymers; Polymerization; Preparation, kinetics, thermodynamics, mechanism and catalysts; SiCl4; Single-site catalyst; Supported catalyst; Zirconia
• ISSN: 0014-3057; 1873-1945
• DOI: 10.1016/j.eurpolymj.2013.09.030

[Display omitted] . •Methylaluminoxane was supported on ZrO2 unmodified and modified with SiCl4.•The supported cocatalysts were applied for living polymerization of propylene.•The modification effect with SiCl4 was clarified by using the living character.•The catalysts also conducted controlled copolymerization of ethylene and 1-hexene. Unmodified and SiCl4-modified spherical zirconia-supported methylaluminoxane were used as cocatalyst for propylene polymerization as well as ethylene/1-hexene copolymerization in combined with Me2Si(η3-C13H8)(η1-NtBu)TiMe2 (1) at 0°C. The modification with SiCl4 improved the catalytic activity. The improvement was clearer in ethylene/1-hexene copolymerization than in propylene polymerization. The number average molecular weight (Mn) of polypropylenes increased linearly against the polymerization time regardless the cocatalyst used to give polymers with narrow molecular weight distribution (Mw/Mn