Lithium soap greases with high drop points - derived from 12-24C fatty acids and 2-12C dicarboxylic acids

摘要

Greases composed of a lubricating oil and a thickener consisting of (A) a Li soao of a 12-24C fatty acid and (B) a Li soap of a 2-12C aliphatic dicarboxylic acid, in molar ratio of 1:0.2-1, are suitable for applicns. requiring greases with high drop points as well as the water-resistance of known Li soap greases, e.g. driving motors of diesel-electric locomotives. Drop points of over 260 degrees C are obtained. Specif., a mixt. of lubricating oil and (A) is produced, the dicarboxylic acid is added and converted into its Li soap under conditions giving a complex of (A) and (B). Complex formation is at 79-115 degrees (88-115 degrees) esp. 99-110 degrees C, and the mixt. contg. (A is substantially dehydrated before neutralisation of (B), and/or neutralisation of (B) is carried out by step-wise addn. of Li(OH). The complete mixt. is dehydrated, quickly heated to 193-205 degrees C and kept for 10 mins. to 1 h. to improve dispersion, followed by rapid cooling.