Issue 10, 2011

Catalyst behaviour for 1-pentene and 4-methyl-1-pentene polymerisation for C2-, Cs- and C1-symmetric zirconocenes

Abstract

1-Pentene and 4-methyl-1-pentene (4M1P) have been polymerised using several C2-symmetric ansa-zirconocene catalysts rac-X(2-R1,4-R2-Ind)2ZrCl2 [X = C2H4, R1 = R2 = H (1); X = SiMe2, R1 = R2 = H (2); X = SiMe2, R1 = Me, R2 = H (3); X = SiMe2, R1 = H, R2 = Ph (4); X = SiMe2, R1 = Me, R2 = Ph (5)] with MAO as cocatalyst. The effects of polymerisation conditions as well as substituents on the indenyl ligand were studied. Except for the poly-1-pentenes synthesized with 3 and 5 at low temperatures, low molecular weight isotactic polymers were generally obtained. Compared to their behaviour in propylene polymerisation, the relative activity and selectivity of catalysts 1–5 are considerably different for 1-pentene and 4M1P polymerisation. Of the five catalysts, 1 and 4 showed the highest activities for both 1-pentene and 4M1P polymerisation, while 5 resulted in the lowest activities, especially for 4M1P polymerisation. Subsequently, a Cs- and several C1-symmetric zirconocenes, (R1)2C(3-R2-Cp)(2,7,-R3-Flu)ZrCl2 (R1 = Me, R2 = R3 = H (6); R1 = R2 = Me, R3 = H (7); R1 = Me, R2 = t-Bu, R3 = H (8); R1 = Me, R2 = R3 = t-Bu (9); R1 = Ph, R2 = t-Bu, R3 = H (10); R1 = Ph, R2 = R3 = t-Bu (11), were tested in 1-pentene and 4M1P polymerisation with MAO as cocatalyst. The effect of substituents on the bridge, the cyclopentadienyl (Cp) and fluorenyl (Flu) ligand, was studied relative to the polymerisation temperature and type of monomer. The molecular weights of the polymers were considerably higher than those of the poly-1-pentenes and P4M1Ps obtained with C2-symmetric zirconocenes (1–5). The catalytic activities and polymer molecular weights strongly depend on the fluorenyl substituent and the bridge, while the type of substituent on the Cp ligand has a strong influence on the tacticity of the polymers.

Graphical abstract: Catalyst behaviour for 1-pentene and 4-methyl-1-pentene polymerisation for C2-, Cs- and C1-symmetric zirconocenes

Article information

Article type
Paper
Submitted
03 Jun 2011
Accepted
04 Jul 2011
First published
15 Aug 2011

Polym. Chem., 2011,2, 2261-2272

Catalyst behaviour for 1-pentene and 4-methyl-1-pentene polymerisation for C2-, Cs- and C1-symmetric zirconocenes

C. Descour, R. Duchateau, M. R. Mosia, G. M. Gruter, J. R. Severn and S. Rastogi, Polym. Chem., 2011, 2, 2261 DOI: 10.1039/C1PY00257K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements