Abstract: The influence of the preparation conditions on the basic properties of tetraurea grease using prefabrication method was investigated, the mechanism of the preparation process was discussed from the perspective of the structure-activity relationship, and the relationship between the macro-properties and the micro-structure was understood. The optimized preparation conditions and basic steps were as follows: reacting at 50-70 ℃ for 30 min, a tetrauret thickener was obtained, which was added to the base oil, stirred and heated to 170-180 ℃, and refined at constant temperature for 1.5 h, the tetrapolyurea grease was obtained after cooling and grinding. The results of performance analysis of lubricating grease showed that the tetrapolyurea grease was prepared from the lightly refined naphthenic base oil, 20% tetrapolyurea thickener by mass and 0.8% extreme pressure antiwear agent by mass. The drop point, working cone penetration and oil separation rate of the prepared tetrapolyurea grease were 318 ℃, 281(0.1 mm) and 0.83%, respectively, and the other properties, such as water resistance, similar viscosity, oxidation stability, extreme pressure and wear resistance, met the quality standard SH/T0789―2007.

Key words: prefabrication method, tetraurea lubricating grease, preparation process, properties