Abstract

The catalytic system methylaluminoxane (MAO) and bis( n-butylcyclopentadienyl)zirconium dichloride (( nBuCp) 2ZrCl 2) was immobilized on commercial silica, silica–alumina and aluminophosphate calcined at different temperatures. The properties of the supports were determined by using N 2 adsorption–desorption isotherms at 77 K, FT-IR spectroscopy and SEM. After aluminium and zirconium impregnation, the catalysts were analyzed by ICP-AES, FT-IR and UV–vis spectroscopy. Ethylene polymerizations were carried out in a Schlenk tube at 70 °C and 1.2 bar of ethylene pressure. The polyethylene obtained was characterized by GPC, DSC and SEM. Catalysts supported on silica–alumina exhibited higher polymerization activity than those supported on silica and aluminophosphate. Besides, the activity of MAO/( nBuCp) 2ZrCl 2 catalytic system supported on silica–alumina and aluminophosphate decreased strongly with support calcination temperature, while remained almost constant when silica was employed as support. All these experimental features suggest a role of the support acid properties and hydroxyl group population in the generation of active polymerization species.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.