SYNTHESIS OF COPOLYMERS OF STEARYL METHACRYLATE WITH N-VINYLPYRROLIDONE AND THEIR USE AS ADDITIVES FOR DIESEL FUEL

The features of radical polymerization of stearyl methacrylate and its copolymerization with N-vinylpyrrolidone by the reversible chain transfer (RAFT) mechanism using 2-cyano-2-propyldodecyltritiocarbonate as a RAFT agent were studied. It has been established that the polymerization process proceeds in a controlled manner without a gel effect up to high conversions and is characterized by a linear increase in the molecular weight of homo- and copolymers with increasing conversion. The molecular weight distribution curves are unimodal; the mode of the synthesized samples consistently shifts to the high-molecular region with increasing conversion. The dispersion of the synthesized images has values of 1.4-1.6. The experimentally determined values of the number-average molecular weight of polymer samples correlate well with the theoretically calculated values. The composition of the copolymers was determined using nuclear magnetic resonance spectroscopy. The dependences of the composition of the copolymer on the composition of the monomer mixture were studied and, based on them, the relative activities of stearyl methacrylate and N-vinylpyrrolidone during their copolymerization in the presence of a RAFT agent were determined using the Fayneman-Ross and Kelen-Tudes methods. It was revealed that the product of the relative activities of the monomers is significantly less than unity, which indicates the formation of a statistical copolymer with an azeotropy point. The resulting polymer samples were tested as depressant additives for hydrotreated diesel fuel. It has been shown that the developed polymer additives are capable of having a significant impact on the low-temperature properties and characteristics of hydrotreated diesel fuel, while simultaneously lowering its pour point, cloud point and ultimate filterability. At the same time, copolymers of stearyl methacrylate with N-vinylpyrrolidone are more effective as depressants than homopolymers of stearyl methacrylate. It has been established that the synthesized copolymers have the most significant effect on the pour point of diesel fuel, in which case the depressant effect exceeds 20 degrees. In terms of their effectiveness in influencing the low-temperature characteristics of diesel fuel, the proposed additives are not inferior to imported analogues currently used in industry and may be of interest in terms of practical use and application. For citation: Pavlovskaya M.V., Dolganov E.D., Belikov A.A., Grishin D.F. Synthesis of copolymers of stearyl methacrylate with N-vinylpyrrolidone and their use as additives for diesel fuel. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2025. V. 68. N 1. P. 63-71. DOI: 10.6060/ivkkt.20256801.7110.