1. Thermal Behavior of Polyethylene Reactor Alloys Polymerized by Ziegler-Natta/Late Transition Metal Hybrid Catalyst.
- Author
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Ahmadjo, Saeid, Dehghani, Samaneh, Zohuri, Gholam Hossein, Nejabat, Gholam Reza, Jafarian, Hamed, Ahmadi, Mostafa, and Mortazavi, Seyed Mohammad Mahdi
- Subjects
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POLYETHYLENE , *POLYMERIZATION , *CHEMICAL reactions , *TRANSITION metals , *THERMAL properties , *MOLECULAR weights - Abstract
Polyethylene reactor alloys are synthesized through heterogeneous ethylene polymerization with a new type of Ziegler-Natta (ZN)/late transition metal (LTM) hybrid catalyst. The effect of various parameters including catalyst composition (LTM/ZN = 0.01, 0.02, 0.04), polymerization temperature (TP = 30, 30-60, 60 °C) and loading temperature (TL = 30, 60 °C) on catalyst activity, chain's vinyl content, viscosity average molecular weight ( Mv) and thermal properties are investigated. Two distinct melting peaks were observed in the ranges of 110-140 °C and 60-90 °C, indicating presence of two different lamellar structures. LTM/ZN ratio shifted melting peaks toward lower values. Rheological properties confirmed homogeneity of polymer blend's microstructure as they follow time temperature superposition. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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