Preparation of linear low‐density polyethylene by in situ copolymerization of ethylene with Zr supported on montmorillonite/Fe/methylaluminoxane catalyst system
作者： Zhicheng Zhang , Cunyue Guo , Nannan Cui , Yucai Ke , Youliang Hu
DOI: 10.1002/APP.21066
关键词:
摘要: Linear low-density polyethylene (LLDPE) was prepared by in situ copolymerization of ethylene with dual-functional catalysts that were composed rac-Et(lnd) 2 ZrCl supported on montmorillonite (MMT) and {[(2-ArN=C(Me)) C 5 H 3 N]FeCl } [Ar = 2,4-C 6 4 (Me) ] oligomerization catalyst. A series polyethylenes different degrees branching obtained adjusting the ratio Fe Zr (Fe/Zr). DSC, NMR, GPC, SEM, density-gradient method used to characterize polymers. With increasing Fe/Zr ratio, densities melting points polymers decreased, whereas molecular weights increased. When increased, activities decreased at atmospheric pressure increased 0.7 MPa pressure. SEM micrographs revealed morphology branched polyethylene, produced catalyst MMT, is better than a homogeneous system.
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