Figure 1 Photograph of the mPAO based polyurea grease A pycnometer method was used to measure the density of the grease. The pycnometer method uses a cup or bottle that holds a known volume. The sample weight is determined by filling the cup to the appropriate volume, weighing it, and subtracting the known weight of the cup or bottle. Results: Table 3 shows some interesting results. First of all, the ratio of blended components did achieve an NLGI grade 2 grease. The cone penetration results show minor changes between worked and unworked penetration results. The oil separation results are good as well as the copper corrosion. Polyurea greases are known for having high dropping points, and this grease also exhibits a high dropping point in excess of 260°C, indicating suitability for applications at high temperatures. This is interesting since the grease was formulated without additives, antioxidants in particular. The Four Ball wear scar shows reasonably good performance especially considering the absence of antiwear additives
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