Morphology and Thermal Characteristics of Polyethylene Nanocomposites Made Using Montmorillonite-Supported Cp2ZrCl2 and Ni-Diimine Precatalysts



Bis(cyclopentadienyl)-zirconium dichloride (Cp2ZrCl2) and (1,4-bis(2,6-diisopropylphenyl)-acenaphthenediimine) dichloronickel (Ni-diimine) were supported on montmorillonite (MMT) pretreated with triisobutylaluminum and 10-undecence-1-ol to produce in situ polyethylene–clay nanocomposites in a gas-phase reactor. The development of the nanocomposite morphology was investigated with transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis. During polymerization, the MMT layers were partially exfoliated by the growing polymer chains, starting from the openings of the clay galleries, but intercalation and exfoliation occurred only to a certain extent. The thermal properties of the nanocomposites we also analyzed by differential scanning calorimetry (DSC).

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