Method of preparing greases

A grease product comprising a lubricating base oil and from about 10-15 wt % thickener, wherein the grease has a dropping point of greater than 500° F. (260° C.), a positive change in penetration value from P(60) to P(100,000) of less than 100 penetration points, and no particles seen at 200× magnification under an optical microscope.

A grease product comprising a lubricating base oil and a thickener, the grease product having a dropping point of greater than 500° F. (260° C.), a positive change in penetration value from P(60) to P(100,000) of less than 100 penetration points, wherein the grease product is made by a method comprising:

• a) preparing a first mixture comprised of a lubricating base oil and at least one amine, and a second mixture comprised of a lubricating base oil and at least one isocyanate,
• b) mixing the two mixtures together in a mixing zone under high pressure in the range of from about 1000 to 8000 psi and high flow rate impingement conditions to thereby have the at least one amine and at least one isocyanate react and have the reaction product dispersed throughout the lubricating base oil, with the reaction and dispersion occurring nearly simultaneously to create a grease product, and
• c) recovering the grease product directly from the mixing zone.