The addition of two-dimensional inorganic nanomaterials can effectively enhance the properties of polyethylene (PE). In the present study, a series of high-performance PE/oleic acid (OA)–siloxene nanocomposites were prepared by in situ polymerization using OA–siloxene-supported Ziegler–Natta catalysts. Compared with the conventional Ziegler–Natta catalyst, the polymerization activity of the OA–siloxene-supported Ziegler–Natta catalyst was enhanced to 100 kg/mol-Ti•h, an increase of 56%. The OA–siloxene fillers exhibited excellent dispersion within the PE matrix through the in situ polymerization technique. Compared to pure PE, PE/OA–siloxene nanocomposites containing 1.13 wt% content of OA–siloxene showed 68.3 °C, 126%, 37%, and 46% enhancements in Tdmax, breaking strength, modulus, and elongation at break, respectively.
