Abstract
Abstract The homopolymerization of ethylene was investigated using the catalysts of (nBuCp)2ZrCl2 supported on PMHS-modified silicas (PMHS=polymethylhydrosiloxane). The effect of the amount of the organosilane polymer on the metallocene grafted content was studied in loadings of PMHS from 0.0 to 3.0 wt.% Si/SiO2, in which the grafted Zr content was from 0.9 to 0.3 wt.% Si/SiO2. The metal contents were determined by Rutherford backscattering spectrometry (RBS), while the catalyst stepwise preparation was monitored by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The chemical environment of the zirconocene surface species were further probed by X-ray spectroscopy (XPS) and the metal distribution was studied by Electron probe microanalysis (EPMA). These catalyst systems produced polyethylenes with a narrow molecular weight distribution using methylaluminoxane as co-catalyst, and their catalyst activities were three times greater than the one obtained with (nBuCp)2ZrCl2 supported on the bare SiO2. Effects of the support structure and the chemical modification on the catalyst performance are presented and discussed.
Sign-in/Register to access full text options 
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 callDisclaimer: 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.
