Synthesis and Properties of Urea Greases Based on Aminoamides of Plant Oil Phosphatides

Abstract

The possibility of using the wastes of the oil and fat industry – phosphatide concentrates as components of lubricating materials was demonstrated in this paper. At the first stage, amidation of phosphatide concentrate from the purification of rapeseed oil by ethylene diamine was carried out using two procedures: without a catalyst and with the use of reagent-catalyst CaO. The samples of urea greases were subsequently synthesized by interaction of amidated phosphatide concentrates with polyisocyanate in the oil media. Aminoamides of fatty acids with polyisocyanate form urea dispersion phase of thixotropic systems, and glycerolphosphatides and calcium glycerolrophosphatides perform the function of tribological additives. The method of infrared spectroscopy proved that the full interaction between polyisocyanate and amidated phosphatide concentrate takes place at the molar ratio of 1:3. Physicochemical properties of the developed urea greases were studied and comparative analysis of their quality indicators with the Maspol brand lubricant was performed. The synthesized urea greases are characterized by high mechanical (a change in penetrations after moving of 100,000 double cycles of 42–45 mm·10 -1 ), colloidal stability (5.2–5.6 % of extracted oil) and high-temperature properties (dropping point above 230 °C). In addition, these thixotropic systems are resistant to oxidation, do not cause corrosion of non-ferrous metals, and are able to operate in contact with water. Phosphorous residues improve the lubricating properties of synthesized compositions without any additional introduction of tribological modifiers (critical load is 980–1,039 N, welding load – 1,568–1,744 N). Due to the use of raw materials of plant origin in the composition of lubricating compositions, their biodegradation is enhanced by 6–7 %