Preparation And Tribological Properties Of Ionic Liquid Lubricating Oil Additives Containing Nitrogen And Boron

In the lubricating oil industry,lubricating oil additives are an important part of lubricating oils,which can effectively improve the tribological properties of lubricating oils,and reduce mechanical friction and wear,extend the service life of equipment.Previous lubricating oil additives usually contain sulfur,phosphorus,and halogens,they will cause serious environmental pollution and fail to meet environmental protection requirements.Therefore,it is imminent to develop environmentally friendly lubricant additives that meet environmental protection requirements and have excellent anti-wear and anti-friction properties.Firstly,five kinds of salicylic acid borate ionic liquid lubricant additives containing no sulfur,phosphorus,chlorine and other elements were synthesized.They are 1,3-dibutylbenzimidazole-bis(salicylato)-borate,1,3-dihexylbenzimidazole-bis(salicylato)-borate,1,3-dioctylbenzimidazole-bis(salicylato)-borate,1-(3-methoxypropyl)-3-butylbenzimidazole-bis(salicylato)-borate,1-(3-methoxypropyl)-3-butylimidazole-bis(salicylato)-borate,and their tribological properties were tested in 500 N and GTL430 lubricants by a four-ball friction testing machine.The test standard is GB/T 3142-1982,and the concentrations of ionic liquid lubricant additives are 0.0%,0.5%,1.0%,1.5%,2.0%,2.5% and 3.0% respectively.Test conditions: temperature is 75?,load pressure is 147 N,the time is 3600 s,and the speed is 1200 r/min.At last,the average wear scar diameter and average friction coefficient of the additives with different mass concentrations in the two lubricating oils are obtained,and the anti-wear and anti-friction properties of the additives are evaluated with this result.The kinematic viscosity of lubricating oil containing ionic liquid lubricating oil additives at 40? and 100? was tested to obtain its viscosity index and evaluate its viscosity-temperature properties.The corrosion resistance of lubricants containing ionic liquid lubricant additives was tested.Test conditions:temperature is 120?,time is 3 h.In order to measure the corrosion resistance of the lubricating oil after adding additives,the corrosion level of the copper sheet is determined by comparing with the corrosion standard color plate.Secondly,five kinds of mandelic acid borate ionic liquid lubricant additives containing no sulfur,phosphorus,chlorine and other elements were synthesized.They are 1,3-dibutylimidazole-bis(mandelato)-borate,1-octyl-3-butylimidazole-bis(mandelato)-borate,1-methylacetate-3-butylimidazole-bis(mandelato)-borate,1-(3-methoxypropyl)-3-butylimidazole-bis(mandelato)-borate,1,3-dioctylbenzimidazole-bis(mandelato)-borate,and their tribological properties were tested in 500 N and GTL430 lubricants by a four-ball friction testing machine.At last,the average wear scar diameter and average friction coefficient of the additives with different mass concentrations in the two lubricating oils are obtained,and the anti-wear and anti-friction properties of the additives are evaluated with this result.The kinematic viscosity of lubricating oil containing ionic liquid lubricating oil additives at 40? and 100? was tested to obtain its viscosity index and evaluate its viscosity-temperature properties.In addition,the corrosion resistance of lubricants containing ionic liquid lubricant additives was tested.This article mainly compares the tribological properties of additives containing different carbon chain lengths,additives containing ester functional groups and additives containing ether functional groups in 500 N and GTL430 lubricants.Among the five salicylic acid borate ionic liquid lubricant additives,1,3-dioctylbenzimidazole-bis(salicylato)-borate shows better anti-wear and anti-friction properties.Among the five mandelic acid borate ionic liquid lubricant additives,1-methylacetate-3-butylimidazole-bis(mandelato)-borate shows excellent anti-wear and anti-friction properties.In short,additives containing long carbon chains and additives containing ester functional groups have good anti-wear and anti-friction effects in lubricating oils.