How can pH value during catalyst preparation affect the performance of vanadium-modified (SiO2/MgO/ MgCl2)•TiClx Ziegler-Natta polyethylene catalysts

نویسندگان

  • Boping Liu State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China
  • Ruihua Cheng State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China
  • Ting Fu State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China
  • Xuelian He State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China
  • Zhen Liu State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China
  • Zhou Tian State Key Laboratory of Chemical Engineering,East China University of Science and Technology, Meilong Road 130, Shanghai 200237, China
چکیده مقاله:

Vanadium-modified (SiO2/MgO/MgCl2)•TiClx Ziegler-Natta catalysts were prepared through co-impregnation of water-soluble magnesium and vanadium salts under different pH values. Several key factors such as pH value of co-impregnation solution during catalyst preparation, catalyst performances including catalytic activity, ethylene/1-hexene copolymerization and hydrogen response were investigated. It is found that the components, structures and performance of the catalysts are obviously affected by changing the pH value (pH=5, 7 and 9) of co-impregnation solution. An appropriate pH value (pH=7) can maximize catalytic activity and hydrogen response, while lower pH value (pH=5) is beneficial to the 1-hexene incorporation. The GPC results show that the polymers obtained have high average molecular weight.

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عنوان ژورنال

دوره 5  شماره 1

صفحات  31- 45

تاریخ انتشار 2018-01-01

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