Lubricants that are based on renewable raw materials have drawn increased attention in various applications, especially those related to the food industry. Due to the high requirements of environmental protection, there is a need to develop biodegradable base oils that are environmentally friendly and do not contain harmful components. The objective of the research was to obtain a base oil with a certain viscosity and certain desired lubricating properties. Base oils were obtained from Crambe abyssinica oil by means of blending with synthetic oil and oxidation. The oxidation processes were carried out in the presence of N-hydroxyphthalimide with or without CO2 as a solvent. As a final result of this study, oil bases meeting the viscosity requirements and showing suitable lubricating properties were obtained. The Raman spectra of the obtained oils were evaluated.

Raw vegetable oil from Crambe abyssinica was subjected to oxidative treatment to enhance its viscosity. The oxidation processes were carried out in the presence of N-hydroxyphthalimide with or without supercritical CO2 as a solvent. Four spectroscopic techniques (Raman, UV-VIS, FT-IR, NMR) were applied to assess the chemical changes taking place during the oxidation. Raman and NMR spectroscopy proved best in the assessment of the chemical transformations leading to increased viscosity of the modified vegetable oil.

Studies on the synthesis of esters of natural origin fatty acids (oleic acid) and a branched synthetic isostearic acid derived from oleic acid with commercially available selected higher polyols in the presence of homogeneous metallic catalysts have been carried out. The effects of the synthesis temperature, molar ratio and the catalysts amount have also been studied. It was shown that higher fatty acid conversion and selectivity to tri- and tetraesters were obtained for organotin catalyst Fascat 2003, which was used as the esterification catalyst. Anti-wear test confirmed good tribological properties of the obtained esters.

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In this paper, we present the study on the synthesis, physico‐chemical, and tribological characterisation of selected plant‐derived fatty acids esters of higher polyols. We described here more effective method synthesis of desired esters with high yields and high selectivities. In our novel and improved synthesis protocol, we applied homogeneous Sn catalysts. Physico‐chemical characterisation and lubricating properties of synthesised esters have been determined and discussed. Our results showed that the synthesised esters are characterised by excellent viscosity, good low temperature, and lubrication properties. High thermal resistance is the main benefit of synthesised esters. For fatty acid esters of trimethylolpropane dimer, onset temperatures are around 400°C and decomposition temperatures above 460°C, which makes these esters applicable in higher temperature.