We report a facile coagglomeration method for preparing graphene (G)/MgCl2‐supported Ti‐based Ziegler‐Natta catalysts. The effects of graphene feed ratio on catalyst morphology and ethylene polymerization behavior ...We report a facile coagglomeration method for preparing graphene (G)/MgCl2‐supported Ti‐based Ziegler‐Natta catalysts. The effects of graphene feed ratio on catalyst morphology and ethylene polymerization behavior were examined. The synthesized catalyst exhibited very high activity for ethylene polymerization. The resultant polyethylene (PE)/G nanocomposites showed a layered morphology, and the graphene fillers were well dispersed in the PE matrix. In addition, the thermal stability and mechanical properties of PE were significantly enhanced with the introduction of a very small amount of G fillers (0.05 wt%). This work provides a facile approach to the production o fhigh‐performance PE.展开更多
In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an inte...In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an internal donor(ID). The chemical compositions of the activated support and the prepared catalyst were examined in detail. During the dissolution of Mg(OEt) 2 support in ethanol medium with CO 2 bubbling, the structure of support changed to magnesium hydrocarbyl carbonate, (CH 3CH 2O) 2- x Mg(O (C O) OCH 2CH 3) x ( x = 1,2). The content of carbonated CO 2 in the activated support was dependent on the heat treatment in the solidification of support. In the preparation procedure of polymerization catalyst, the activated support was treated with TiCl 4 so that the structure of support was converted to MgCl 2 with the incorporation of ID. The polymerization behavior of the pre-pared catalyst was also studied in the presence of phenyltriethoxysilane as an external donor.展开更多
基金supported by the National Research Foundation of Korea (NRF-2015R1D1A1A0161012)the National Natural Science Foundation of China (U1462124)~~
文摘We report a facile coagglomeration method for preparing graphene (G)/MgCl2‐supported Ti‐based Ziegler‐Natta catalysts. The effects of graphene feed ratio on catalyst morphology and ethylene polymerization behavior were examined. The synthesized catalyst exhibited very high activity for ethylene polymerization. The resultant polyethylene (PE)/G nanocomposites showed a layered morphology, and the graphene fillers were well dispersed in the PE matrix. In addition, the thermal stability and mechanical properties of PE were significantly enhanced with the introduction of a very small amount of G fillers (0.05 wt%). This work provides a facile approach to the production o fhigh‐performance PE.
文摘In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an internal donor(ID). The chemical compositions of the activated support and the prepared catalyst were examined in detail. During the dissolution of Mg(OEt) 2 support in ethanol medium with CO 2 bubbling, the structure of support changed to magnesium hydrocarbyl carbonate, (CH 3CH 2O) 2- x Mg(O (C O) OCH 2CH 3) x ( x = 1,2). The content of carbonated CO 2 in the activated support was dependent on the heat treatment in the solidification of support. In the preparation procedure of polymerization catalyst, the activated support was treated with TiCl 4 so that the structure of support was converted to MgCl 2 with the incorporation of ID. The polymerization behavior of the pre-pared catalyst was also studied in the presence of phenyltriethoxysilane as an external donor.
