Vanadium catalyst systems (SIL1–3A(B)/V) for ethylene polymerization were obtained by immobilization of the Cp2VCl2 precursor (V) in the ionic liquid 1‐[3‐(triethoxysilyl)propyl]pyridinium chloride (IL), modified by AlCl3 and AlEtCl2 (A) or AlEt2Cl (B), and supported on three types of silica carrier S1–3. The properties of the ionic liquid supports were determined using Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller measurements, scanning electron microscopy and elemental analysis. The best results (above 2 tons PE (mol V)−1 (0.5 h)−1) were obtained using the catalyst system SIL3B/V. Addition of ethyl trichloroacetate is possible in the ionic liquid medium and it further increases the activity up to 7 tons PE (mol V)−1 (0.5 h)−1. In contrast, application of the imidazolium ionic liquid to the SIL system or application the analogous catalyst system without the ionic liquid results in lower activities. The obtained polyethylene (PE) is a linear polymer, with molecular weight (Mw) of over 106 g mol−1 and molecular weight distribution (Mw/Mn) in the range 1.6–1.9, and has a characteristic fluffy or fibrous shape. In contrast, the PE samples obtained using the systems without ionic liquid reveal broader Mw/Mn (2.5–3.7) and replicate the support morphology. © 2016 Society of Chemical Industry

Molecules of the title compound, C15H16O5S, are composed of a 3,5-dimethoxyphenyl moiety substituted with a toluene-4-sulfonate group. The dihedral angle between two aromatic rings is 57.23 (4)°. In the crystal, molecules are connected by weak C—H...O hydrogen bonds and S...O van der Waals interactions.

Molecules of the title compound, C15H10F6O3S, are composed of 3,5-bis(trifluoromethyl)phenyl substituted with a toluene-4-sulfonate group. The dihedral angle between two aromatic moieties is 45.10 (5)°. In the crystal, molecules are connected by weak C—H...O and C—H...F contacts. One of the trifluoromethyl groups is disordered.

Molecules of the title compound, C19H16O3S, are composed of a biphenyl moiety substituted with a toluene-4-sulfonate group. The dihedral angle between the two coplanar biphenyl rings and the toluene ring is 52.72 (6)°.