| 摘要 |
The combination of an oil-soluble polyol ester reaction product having a number average molecular weight (Mn) of from about 1,300 to 8,000, e.g., the reaction product of polybutenyl succinic anhydride with pentaerythritol which reaction product can be borated, if desired, and an oil-soluble acylated nitrogen compound having a (Mn) of from about 1,300 to 8,000, e.g. polybutenyl succinic anhydride reacted with an alkylene polyamine such as tetraethylene pentamine, which nitrogen compound can be borated, if desired, are surprisingly useful as combined additives for lubricating oils to increase the dispersancy and varnish inhibition properties of said oil when one part per weight of said polyol ester reaction product is combined with from 0.2 to 4, preferably 1 to 3, parts by weight of said acylated nitrogen compound. |
