English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Iron(II) and cobalt(II) complexes consisting of bis(imino)pyridine ligands having various substituents were investigated as catalysts for the polymerization of ethylene1)~5). Although these complexes combined with methylaluminoxane (MAO) polymerize ethylene with an extremely high activity, no significant activities were observed for the propylene polymerization and ethylene/α-olefin copolymerization. Moreover, competitive chain-transfer reactions that occurred on multiple active species results in the formation of low molecular-weight polyethylene having a high polydispersity (PDI). From the viewpoint of the industrial production of polyethylene, catalysts must be able to produce high molecular weight polyethylene and promote the copolymerization of ethylene and α-olefin. Among the transition metal complexes having a bis(imino) pyridine backbone, the bis(imino)pyridinevanadium(III) complexes have been investigated, because these combined with MAO show a significant activity for the polymerization or oligomerization of ethylene6)~16). Moreover, as remarkable properties, these complexes promoted the copolymerization of ethylene and α-olefin6), and the supported catalysts using a modified magnesium chloride can produce high-molecular weight polyethylene13). When metal complexes are used for most of the industrial polymerization processes, they must be immobilized on carriers. Recently, we developed supported catalysts consisting of a bis(imino)pyridineiron (II) complex and a cation-exchanged clay mineral as the carrier17). These catalysts are readily activated by conventional alkyl aluminum compounds and showed a high activity for the polymerization of ethylene. Additionally, well-controlled polyethylene particles obtained using those catalysts were able to be used in a slurry process. In the present study, we prepared the bis(imino)pyridinevanadium(III) complexes (Fig. 1) and the supported catalyst consist ing of Mg2+exchanged clay minerals and the complexes. Moreover, the copolymerization of ethylene and 1-hexene was carried out using these supported catalysts combined 108 Journal of the Japan Petroleum Institute, 54, (2), 108-113 (2011)

journal of the japan petroleum institute

Homo- and Co-polymerization of Ethylene with 1-Hexene Using Heterogeneous Catalysts Consisting of Bis(imino)pyridinevanadium Complex Supported on Clay Minerals and Alkyl Aluminum Compounds