Molecules, Год журнала: 2025, Номер 30(8), С. 1847 - 1847

Опубликована: Апрель 20, 2025

The catalytic performance of α-diiminonickel complexes is highly sensitive to structural modifications in their ligand frameworks. In this study, a series unsymmetrical 2,3-bis(arylimino)butane-nickel featuring ortho-2,6-dibenzhydryl groups as sterically demanding motifs and para-methyl electron-donating enhancers were proposed synthesized. These nickel thoroughly characterized using FTIR, elemental analysis, single-crystal X-ray diffraction (for Ni4 Ni5), revealing deviations from ideal tetrahedral geometry. Upon activation with Et2AlCl, these demonstrated exceptional ethylene polymerization activity, achieving remarkable value 13.67 × 106 g PE mol-1 (Ni) h-1 at 20 °C. Notably, even 80 °C, the maintained high activity 1.97 h-1, showcasing superiority compared previously reported complexes. resulting polyethylenes exhibited ultra-high molecular weights (Mw: 3.33-19.47 105 mol-1) tunable branching densities (84-217/1000C), which effectively controlled by temperature. Moreover, mechanical properties polyethylenes, including tensile strength (σb = 0.74-16.83 MPa), elongation break (εb 271-475%), elastic recovery (SR 42-74%), finely tailored optimizing weight, crystallinity, degree. prepared displayed outstanding recovery, hallmark high-performance thermoplastic elastomers, making them promising candidates for advanced material applications.

Язык: Английский