Abstract
AbstractTo investigate the Phillips catalyst for ethylene polymerization, a family of silsesquioxane‐supported chromium catalysts with a bipodal structure have been synthesized from trivalent or hexavalent chromium precursor and fully characterized by 1H/13C/29Si NMR, FT‐IR, and UV–vis spectroscopies. Upon activation with tri‐n‐octylaluminum or butylated hydroxytoluene (BHT) modified TIBA following the “TIBA‐BHT”, all the silsesquioxane‐supported chromium catalysts display moderate activities (50–523 g‐PE•g‐cat−1·h−1) for ethylene polymerization, producing polyethylene (PE) with high methyl branching level (0.1–1.3/1000C) and a clear bimodal molecular weight distribution (MWD). Catalysts with hexavalent chromium precursor exhibit higher activities than trivalent ones. The type of activator and coordination environments of the active site play a key role in the MWD of obtained PE.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.