MgCl₂‐supported Ziegler–Natta catalyst containing dibenzoyl sulfide donor for propylene polymerization

Abstract

Polypropylene (PP) was synthesized in the presence of Ziegler-Natta catalysts composed of MgCl 2 -TiCl 4 -internal donor/ AlR 3 -external donor. Diisobutyl phthalate is a well-known internal donor in current PP production. Nevertheless, phthalates are often blamed as endocrine disruptors. The objective is to find an ecofriendly internal donor producing PP with maintaining its physical properties. When using dibenzoyl sulfide, synthesized PP shows the superiority to diisobutyl phthalate in the activity of catalyst (40 vs. 22 kg PP/g catalyst), the isotacticity of polymer (99.5 vs. 98.0 wt % of heptane insolubles), and the molecular weight distribution of PP product (M w /M n 5 4.8 vs. 4).

Modeling Coadsorption of Titanium Tetrachloride and Bidentate Electron Donors on Magnesium Dichloride Support Surfaces

“…The two surfaces differ in coordination of the surface magnesium atoms; the (104) surface features five-coordinate magnesium atoms, whereas the (110) surface features four-coordinate magnesium atoms (Figure ). , The unsaturated magnesium atoms generate adsorption sites for titanium tetrachloride and electron donors . Adsorbed titanium tetrachloride transforms into polymerization active sites through activation by the cocatalyst. − Electron donors, which are added during the catalyst preparation, have an influence on the morphology of the catalyst support − as well as on the distribution and stereoselectivity of the active sites. − …”

The role of organoaluminum and electron donors in propene insertion on the Ziegler–Natta catalyst

“…9–11 Cooperation between internal and external donors contributes to the catalyst's activity and the isotacticity of polypropylene. 12–14…”

Understanding the Role of Sulfonyl Amine Donors in Propylene Polymerization Using MgCl2-Supported Ziegler–Natta Catalyst

“…Compared to the fourth-generation catalyst containing diisobutyl phthalate (D i BP, the commercial internal donor), the bioderived diesters have reasonable activity and stereospecificity in propylene polymerization . The dibenzoyl sulfide donor and the eco-friendly salicylate donor were reported to show superiority to D i BP in terms of catalytic activity and isotacticity of polypropylene. , Nissinen et al first reported the multidentate donor polyethylenimine, an amino-functional polymer, was used as an internal donor in the copolymerization of ethylene/1-butene and showed high catalytic activity. DFT results showed that branched polyethylenimines could stabilize the MgCl 2 (104) surface through primary amino groups .…”