Dispersant and Detergent Additives for Lubricants

Antioxidant additives can not totally prevent the oxidation phenomenon, especially with the modern trend in oil-change intervals at the end of the interval, oil contains a significant quantity of insoluble oxidized material. 

It is necessary to keep these materials suspended in the oil to avoid the formation of varnishes on the engine walls and deposits in the crankcase. 

Two types of compounds having different functions are used detergents and dispersants. 

Dispersants and detergents are surfactants in organic media and contain an oleophilic hydrocarbon part and a hydrophilic polar part. 

In the case of lubricant detergents, the hydrophilic or polar part is a metallic salt (calcium, magnesium) and at the center of the micelle it is possible to store a reserve of a metal base (lime or magnesia) the detergent will be able therefore to neutralize the acids produced by oxidation of the oil as soon as they are created. 

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