Integrated synthesis of metallocene@support catalysts based on glyphosate and its zirconium derivatives

Abstract

Three new kinds of composite metallocene catalyst, Cp₂Zr@Gly, Cp₂Zr@ZrGp and Cp₂Zr@EXZrGP, for ethylene polymerization were synthesized based on matrixes of glyphosate (Gly), layered zirconium glyphosate (ZrGP) and exfoliated zirconium glyphosate (EXZrGP), and their catalytic activity in ethylene polymerization was studied. The catalytic activities of Cp₂Zr@Gly, Cp₂Zr@ZrGp and Cp₂Zr@EXZrGP are 3.8 × 10⁵, 3.3 × 10⁵ and 4.8 × 10⁵ gPE per mol_Zr per h per bar at a temperature of 60 °C and after a time of 1.0 h, higher than that of the catalyst Cp₂ZrCl₂@SiO₂ (2.3 × 10⁵ gPE per mol_Zr per h per bar), which is now used in industry. The catalytic activities of the three new catalysts are also higher than that of the catalyst Cp₂ZrCl₂ (3.0 × 10⁵ gPE per mol_Zr per h per bar) under the same conditions. Exfoliation of the activity centers from the support and reactor fouling phenomena were all found to be avoided during the course of the polymerization.