Details

Autor(en) / Beteiligte

• Li, Hongbo
• Li, Liting
• Marks, Tobin J
• Liable-Sands, Louise
• Rheingold, Arnold L

Titel

Catalyst/Cocatalyst Nuclearity Effects in Single-Site Olefin Polymerization. Significantly Enhanced 1-Octene and Isobutene Comonomer Enchainment in Ethylene Polymerizations Mediated by Binuclear Catalysts and Cocatalysts

Ist Teil von

• Journal of the American Chemical Society, 2003-09, Vol.125 (36), p.10788-10789

Ort / Verlag

Washington, DC: American Chemical Society

Erscheinungsjahr

2003

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• This Communication describes the implementation of a new binuclear homometallic organotitanium “constrained geometry catalyst” (CGC), (μ-CH2CH2-3,3‘){ (η5-indenyl )[1-Me2Si ( t BuN)](TiMe2)}2[EBICGC(TiMe2)2; Ti 2 ], together with the bifunctional activators (Ph3C+)2[1,4-(C6F5)3BC6F4B(C6F5)3]2- (B 2 ) and new bisborane 1,4-(C6F5)2BC6F4B(C6F5)2 (BN 2 ) in ethylene + α-olefin copolymerization processes. Specifically examined are the comonomers 1-octene and poorly responsive isobutene. Large increases in comonomer enchainment efficiency into the polyethylene microstructure are observed versus the corresponding mononuclear catalyst [1-Me2Si(3-ethylindenyl)( t BuN)]TiMe2 (Ti 1 ) + Ph3C+B(C6F5)4 - (B 1 ) or B(C6F5)3 (BN) under identical polymerization conditions. In ethylene + 1-octene copolymerization, 11 times more 1-octene incorporation is observed for Ti 2 + B 2 vs Ti 1 + B 1 . In ethylene + isobutene copolymerization, 5 times more isobutene incorporation is observed for Ti 2 + BN 2 vs Ti 1 + BN.