METHOD OF PREPARING ADDITION AGENT FOR LUBRICATING OILS Russian patent published in 2002 - IPC

FIELD: petrochemistry, more particularly preparation of alkylphenol addition agent for lubricating oils. SUBSTANCE: addition agent is prepared by reacting alkylphenol C₈-C₁₈ with elementally sulfur at temperatures from 140 to 180 C in the presence of basic type catalyst. The resulting product is treated with alkane thiol in which R is C₄-C₁₈ alkyl at temperatures from 50 to 170 C and at alkylphenol to alkanethiol molar ratio of 1:0.02-0.3 for 0.5 to 5 h. EFFECT: higher thermal stability and lower corrosion with respect to non- ferrous metals. 2 cl, 7 ex, 1 tbl