Metallocene/Borate-Catalyzed Polymerization of Amino-Functionalized α-Olefins

• Published in: Macromolecules 1998-04, Vol.31 (7), p.2019-2027
• Main Authors: Stehling, Udo M, Stein, Kevin M, Kesti, Michael R, Waymouth, Robert M
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Polymerization; Preparation, kinetics, thermodynamics, mechanism and catalysts
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma971053c

Cationic metallocene/borate catalysts, generated from zirconocene dimethyl compounds, L n ZrMe2, and anilinium borate, [HNMe2Ph]+[B(C6F5)4]-, were used to polymerize 5-amino-1-pentenes and one 4-amino-1-butene with dimethyl, diethyl, diisopropyl, or diphenyl substitution patterns on nitrogen. The monomer 5-(N,N-diisopropylamino)-1-pentene showed the highest activity with Cp*2ZrMe2/borate and was used for all further investigations. The catalytic system Cp*2ZrMe2/borate was 4 times more active than the corresponding methylaluminoxane-based system and 180 times more active than the heterogeneous system, TiCl3/Al(i-Bu)3. 1-Hexene and 5-(N,N-diisopropylamino)-1-pentene were polymerized with Cp*2ZrMe2 and rac-ethylenebis(tetrahydroindenyl) zirconium dimethyl, rac-EB(THI)ZrMe2. Polymerization of both monomers with Cp*2ZrMe2 displayed similar activities. Hexene polymerizations with rac-EB(THI)ZrMe2 were 30 times more active than those with aminopentene. 5-(N,N-Diisopropylamino)-1-pentene polymerizations gave rise to isotactic poly(aminopentene) with C 2 symmetric catalysts, syndiotactic polymer with a C s symmetric catalyst, and atactic polymer with achiral catalyst precursors.