POSSIBILITY OF APPLICATION FOR ETHERS OF ACONITE ACID AS AW/EP ADDITIVE

The possibility of using substances containing only carbon, hydrogen and oxygen as antiwear additives for lubricating oils has been investigated. Studies have been conducted on the example of ethers of aconite acid and hexadecyl alcohol. This compound was chosen as a promising AW/EP additive for biodegradable greases based on vegetable oils. In addition, the anti-wear mechanism of substances that do not contain phosphorus, sulfur, chlorine, metals and other heteroatoms is very interesting. Aconite acid hexadecyl ester was added to rapeseed oil, to petroleum oil without additives, and to standard gear oil. Antiwear properties of the obtained compounds were identified and presented as results. Measurements were carried out both in laboratories of SUSU and at Sofia University at several stands under various friction conditions. It was established that the test additive exhibits anti-wear properties in all three lubricating oils. With the introduction of additives in rapeseed oil, wear is reduced by 25 ... 50% depending on the test conditions. The wear reduction is more significant in steel-bronze contacts than in steel-steel and steel-iron contacts. With the introduction of additives in hydrocarbon oil without additives, anti-wear effect is only slightly lower than with the introduction of ZDDP. Anti-wear effect increases with increasing load (contact pressure), as well as for ZDDP. The most pronounced effect for both vegetable and petroleum oil, obtained by testing the method of four balls according to the technique of ASTM D 4172. When hexadecyl aconite acid is added to gear oil (GL-5 standard) containing ZDDP and EP additives, wear is reduced to the same extent as when it is added to oil without additives. The welding load increases slightly. This suggests that the studied additive does not compete with ZDDP and can be used in mixed composition. The absence of heteroatoms in the studied additive indicates an adsorption mechanism of anti-wear action. The study results indicate the prospects for the use of esters of polyatomic acids as AW/EP additives for biodegradable lubricating oils and oils for food production equipment.