Synthesis of ultra‐low‐molecular‐weight polyethylene wax using a bulky Ti(IV) aryloxide–alkyl aluminum catalytic system

Abstract

Complexes of titanium(IV) with bulky phenolic ligands such as 2-tert-butyl-4 methylphenol, 2, 4-di-tert-butyl phenol and 3,5-di-tert-butyl phenol were prepared and characterized. These catalyst precursors, formulated as [Ti(OPh * ) n (OPr i ) 4−n ] (OPh * = substituted phenol), were found to be active in polymerization of ethylene at higher temperatures in combination with ethylaluminum sesquichloride (Et 3 Al 2 Cl 3 ) as co-catalyst. It was observed that the reaction temperature and ethylene pressure had a pronounced effect on polymerization and the molecular weight of polyethylene obtained. In addition, this catalytic system predominantly produced linear, crystalline ultra-lowmolecular-weight polyethylenes narrow dispersities. The polyethylene waxes obtained with this catalytic system exhibit unique properties that have potential applications in surface coating and adhesive formulations.

New bis(aryloxy)–Ti(iv) complexes and their use for the selective dimerization of ethylene to 1-butene

“…The other signals were consistent with the formation of the mono-aryloxy complex 2e. Interestingly, when two equivalents of phenol 1d having a tert-butyl group at only one ortho position were used, the 1 H NMR spectrum was consistent with the presence of the di-substituted complex 2d 2 as reported by Umare et al 21 The 13 C NMR spectrum presented a doubling of the signals in the aromatic region. The same feature was observed when phenol 1c was used.…”

Metallocene Polyethylene Wax Synthesis

“…Polyethylene waxes (PE-waxes) are polymers with molecular weights ( M n ) less than 10 kg mol –1 . , PE-waxes can be made directly from the polymerization of ethylene under controlled conditions or by the thermal degradation of higher molecular weight polymers. , Because of their hydrophobicity and chemical and heat stability, , PE-waxes are used in plastic processing applications to improve product physical appearance and thermal properties. PE-waxes are also commonly used as additives to impart mark, slip, rub, and scratch resistance in printing inks and paints, improve the fusing properties in toner formulations, improve the mechanical properties of surface coatings, and act as lubricating agents in plastic processing. ,,− PE-wax dispersions, obtained by the redispersion of low-density polyethylene (LDPE) in water, − are targeted for use in coating applications in the paper industry .…”

“…Polyethylene waxes (PE-waxes) are polymers with molecular weights ( M n ) less than 10 kg mol –1 . , PE-waxes can be made directly from the polymerization of ethylene under controlled conditions or by the thermal degradation of higher molecular weight polymers. , Because of their hydrophobicity and chemical and heat stability, , PE-waxes are used in plastic processing applications to improve product physical appearance and thermal properties. PE-waxes are also commonly used as additives to impart mark, slip, rub, and scratch resistance in printing inks and paints, improve the fusing properties in toner formulations, improve the mechanical properties of surface coatings, and act as lubricating agents in plastic processing. ,,− PE-wax dispersions, obtained by the redispersion of low-density polyethylene (LDPE) in water, − are targeted for use in coating applications in the paper industry . They are also used as surface modifiers for primers, paints, inks, coatings, and lubricants .…”

Obtaining and evaluation of polyethylene nanocomposites with graphene nanoplatelets through in‐situ ethylene polymerization

“…[39] On the other hand, PE/G3 material showed the lowest T c and T m , which can be mainly due to their very low M w (1802 g/mol), more than to its high concentration of GNP (12.5 wt.%) since its T c and T m are comparable to those of lineal PE oligomers. [40] Figure 3 displays TGA curves for neat polyethylene (PEB) and nanocomposites (PE/G1 and PE/G2). It can be seen that, when compared to the corresponding TGA curve of PEB, PE/G1 maintains a degradation temperature similar to that of HDPE.…”