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Novel phase change materials based on paraffin and alumina-filled polyethylene (FPE) were prepared using a two-step process. In the first step, PE is synthesized using metallocene catalyst system. The synthesized PE is subsequently purified, whereas hydrated alumina-PE composites will be formed by the hydrolysis of aluminum organic cocatalyst and dispersion of hydrated alumina in the PE matrix. In the second step, paraffin-alumina-FPE composites were prepared by using the ex situ technique. Scanning electron microscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry were used to evaluate the structure and thermal properties of the composites. The results show that the incorporation of a suitable amount of alumina into the composites changes their thermal stability. It is also possible to improve the thermophysical properties of the thermal energy storage materials by altering the paraffin ratio to the FPE.

A review of the scientific and patent literature on oligomerization of ethylene to linear olefins in the presence of homogenous or heterogeneous zirconium complexes and various aluminum organic compounds has been fulfilled for last twenty‐five years. Over these years, a wide range of studies had been conducted for selective oligomerization of ethylene into a narrow fraction of linear α‐olefins such as C4‐C8 and C6‐C10 fractions. During the discussion of these catalytic systems, exceptional attention is also paid to feature works such as the activity of the catalysts and the acquisition of clear liquid product without any trace of polymer, all of which play important roles in the selection of the best technology.

The article is dedicated to the development of processes for (oligo)alkylation of petroleum fractions rich in aromatic hydrocarbons, with α-olefins (hexene-1, octene-1, decene-1) in the presence of ionic-liquid catalytic systems and the study of the properties of the products obtained. Alkylation reactions were carried out in the presence of chloroaluminate ionic liquids; for the first time a (nano)metal-polymer composite (NMPC) was used in the catalytic system as a modifier, and zinc chloride (ZnCl2) was used in the catalytic system as a component and the results were compared. It has been shown that these ionic liquid catalytic systems (ILCS) are suitable for (oligo)alkylation reactions and the use of these additives in their composition will lead to efficient alkylation. The products obtained were analyzed by IR-, NMR- spectroscopy, fluorescent indicator adsorption methods, and size exclusion chromatography. It was shown that these petroleum fractions rich in aromatic hydrocarbons can be used as alkylation components, and depending on the composition of the ILCS, it is possible to regulate the molecular, thermophysical and other characteristics of the products obtained based on them. The alkylated products obtained have been tested as plasticizing additives in polyolefin composites.

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