Modified mesoporous magnesium ethoxide with spherical morphology for polypropylene Ziegler-Natta catalyst: preparation and characterization

摘要

Magnesium ethoxide (MGE) was modified by addition of co-solvent (2-propanol) and manganese chloride (MnCl2) together and as a spherical support it was used to obtain Ziegler-Natta (Z-N) catalyst in the polymerization of propylene. The effect of 2-propanol and MnCl2 on nanostructure and morphology of MGE was investigated. The spherical and mesoporous MGE samples were characterized by specific surface area (BET), X-ray diffraction technique (XRD) and scanning electron microscopy (SEM). The relation between the synthetic procedure of MGE support and its structure was discussed. The modification of MGE by 2-propanol and MnCl2 showed a drastic change in the shape of plate-like building blocks of the support. The mean pore size of the modified MGE support was in the range of 4.6-5.2 nm and its surface area was in the range of 31.3-45.4 m(2) g(-1). The synthesized catalyst with modified MGE showed good activity in propylene polymerization with more than 99% isotacticity. The results showed that the fabricated spherical MGE would be a good condidaite support for Z-N catalysis application.