Due to the many risks of using chlorinated alkylaluminum cocatalysts (CACs), reducing or omitting their amount in methods used for synthesizing Ziegler–Natta catalysts (ZNCs) has always been a dream of polymer chemists. CACs play a crucial role in the chlorination of Mg­(OR)2 supports, which are the most industrially favorable precursors in ZNCs’ recipes. In this article, using a systematic investigation, an initiative approach has been suggested to chlorinate the supports using halocarbons and chlorine-free alkylaluminum cocatalysts (CFACs). It was evidenced that the successive addition of a CFAC and a halocarbon to a suspension of Mg­(OR)2 is a reliable method for chlorine atom exchange between the halocarbon and Mg­(OR)2. Doing so, a highly active ZNC was produced and characterized mainly by inductively coupled plasma, X-ray diffraction, and X-ray photoelectron spectroscopy techniques. In the next step, the catalyst’s performance in monomodal and bimodal copolymerization reactions of ethylene and 1-butene was investigated, and the produced copolymers were fully characterized. The characterizations were carried out using numerous techniques such as rheometric mechanical spectroscopy (RMS), self-nucleation and annealing, differential scanning calorimetry, mechanical tests, and so forth, and their results were compared with a famous ZNC whose support was chlorinated with a CAC. Finally, a possible mechanistic pathway for the reaction between Mg­(OR)2 and halocarbons using CFACs as a chlorine transporter was described. All in all, it was revealed that the new approach could be relied upon as a promising way to chlorinate Mg­(OR)2 supports without using dangerous and corrosive CACs. The produced copolymers using the new formulation had the same physical and mechanical properties as those made by industrial counterparts.

Inorganic halide additives can act as dopants and/or chlorine-donating species in Ziegler–Natta recipes.

In this paper, two Zigler‐Natta catalysts (ZNCs) were used to synthesize a commercially available linear low‐density polyethylene (LLDPE), widely used in the packaging industry, on an industrial scale. The catalysts differ only in their ability to distribute comonomers between short and long chains. Both catalysts were fully characterized in the first section, and two similar ethylene/1‐butene copolymers were made using them. Afterward, the produced copolymers were fully characterized using different techniques; namely, differential scanning calorimetry (DSC), successive self‐nucleation and annealing (SSA), oxygen induction time (OIT), melt flow index (MFI), rheometric mechanical spectroscopy (RMS), and a wide range of mechanical experiments. It was revealed that while the presence of comonomers in short chains can reduce their resistance against oxidation (by more than 30%) and can cause a dramatic change in friction coefficients (by more than 20%), some of the other main mechanical properties of the made copolymers were independent of comonomer distribution between long and short chains. In addition, it was shown that ethylenic copolymers' strain hardening modulus (SHM) takes advantage of the homogenous distribution.

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The relationship between career resin of carbon black (CB) masterbatch and the performance of bimodal polyethylene pipes (PE100) under ultraviolet (UV) irradiation and the long-term stability of black PE100 with different comonomer content have been investigated. For this purpose, two different CB masterbatches varying in carrier resin were selected and added to two PE100 pipes.Samples were exposed to UV irradiation, and then thermal, mechanical, and rheological properties were explored using differential scanning coloriemetry (DSC), tensile, and rheometry analyses. Additionally, Fourier transformed-infrared spectroscopy (FTIR) has been performed to characterize the structural changes of PE100 samples under UV irradiation. According to rheological results, the PE100 sample containing more comonomer underwent a higher degree of degradation. Thermal and mechanical results reveal that the masterbatch composed of highdensity polyethylene (HDPE) as carrier resin has a better influence on PE pipes' UV stability with less comonomer content.