Ziegler–Natta catalysts for propylene polymerization: Morphology and crystal structure of a fourth-generation catalyst

2006 ◽  
Vol 239 (2) ◽  
pp. 347-353 ◽  
Author(s):  
M CHANG ◽  
X LIU ◽  
P NELSON ◽  
G MUNZING ◽  
T GEGAN ◽  
...  
2017 ◽  
Vol 46 (13) ◽  
pp. 4452-4460 ◽  
Author(s):  
V. H. Nissinen ◽  
I. O. Koshevoy ◽  
T. T. Pakkanen

Chelating oxygen and nitrogen donor ligands (1,2-dimethoxyethane, 1,3-dimethoxypropane, and N,N′-diethylethylenediamine) are found to dictate the crystal structure formation of MgCl2, the important support component of a polymerization catalyst.


2013 ◽  
Vol 31 (4) ◽  
pp. 583-590 ◽  
Author(s):  
Jie Hu ◽  
Bin Han ◽  
Xian-rong Shen ◽  
Zhi-sheng Fu ◽  
Zhi-qiang Fan

2012 ◽  
Vol 43-44 ◽  
pp. 36-41 ◽  
Author(s):  
Harri Heikkinen ◽  
Tiina Liitiä ◽  
Ville Virkkunen ◽  
Timo Leinonen ◽  
Tuulamari Helaja ◽  
...  

1994 ◽  
Vol 51 (6) ◽  
pp. 1029-1034 ◽  
Author(s):  
Fernanda M. B. Coutinho ◽  
Marcos A. S. Costa ◽  
Luiz C. Santa Maria ◽  
José C. Bruno

2000 ◽  
Vol 6 (S2) ◽  
pp. 33-34
Author(s):  
V. Oleshko ◽  
P. Crozier ◽  
R. Cantrell ◽  
A. Westwood

The large-scale commercial production of polyolefins by catalytic Ziegler-Natta polymerization have stimulated the development of the third, fourth and fifth generation heterogeneous catalysts comprising high surface area defective MgCl2 with TiCl4, electron donors, and AlR3-co-catalysts. In spite of intensive research over the years, the present level of understanding of the catalysts is still incomplete because of their complex composition leading to a multitude of local active site environments. The aim of this work is to provide a new insight into the process via in situ video microscopy of gas phase propylene polymerization over MgCl2-supported Ziegler-Natta catalysts combined with ex situ characterization by light and electron microscopy techniques (SEM, TEM, HRTEM, STEM, PEELS and windowless EDX). Procedures for catalyst synthesis are described elsewhere. The catalysts were stored in a dry box under a He atmosphere (<lppm H2O/O2). Samples were transferred to specimen holders in the dry box and then transferred into the microscopes under high purge N2 conditions to prevent poisoning of the catalysts by air and moisture.


Sign in / Sign up

Export Citation Format

Share Document