The Important Function of Lubricating Oil Additive and Related Research

- Aug 10, 2020 -

Oil additives

There are many different kinds of Oil additives, different function, according to the role of the additive, it can be divided into viscosity index improver, detergent, dispersant, oily agent (friction modifier), extreme pressure anti-wear agent, antioxidant, rust corrosion inhibitor, emulsifying agent and emulsifier, blood coagulation agent, suspending agent, antifoaming agent, etc. The cleaning agent, oil agent (friction improver), extreme pressure anti-wear agent, rust and corrosion resistant agents mainly protect the metal surface; Viscosity index improvers, dispersants, antioxidants, anti-emulsifiers and emulsifiers, depressants, suspension agents, anti-foam agents, etc. are used to improve the performance of base oils.

The Important Function of Lubricating Oil Additive and Related Research

Friction Modifier

When the load between Friction pairs is small, the Friction Modifier can form a protective film on the surface of Friction pairs to prevent severe wear between metals. When the metal surface bears a large load or when the mechanical equipment runs at a fast speed, due to the local pressure is too large, the metal press welding together, the metal surface will be in direct contact, making the friction more intense, and produce a lot of heat, the anti-wear agent formed on the metal surface lubrication film will be destroyed. Therefore, a more effective additive than the anti-wear agent is needed, which is called extreme pressure additive. Extreme pressure additives can produce a layer of chemical reaction film with low shear strength on the metal surface, avoid abrasion, sintering, sticking and abrasion on the metal surface under high speed and high load or high temperature, and improve the bearing capacity of the metal to meet the lubrication requirements under harsh working conditions.

In the practical application process, the anti-wear agent and extreme pressure additives are not strictly distinguished, generally referred to as absolute pressure anti-wear agents.Traditional perfect pressure anti-wear agent according to the different elements in the main are divided into sulfur, phosphorus, chlorine and nitrogen, boron and metal (such as lead, zinc, molybdenum) compounds and multielement composite element, its representative respectively inorganic borate, organic borate ester, naphthenic acid lead, ZDDP additives, MoS2 and MoDTC, MoDTP compounds containing many kinds of active elements, etc.

In the process of friction, the additives in the active elements such as sulfur, phosphorus, chlorine is released, by physical or chemical adsorption form adsorption film on metal surface, or react with the metal surface, chemical reaction film, to separate the two metal surface, to prevent wear and tear on the surface of the metal and sintering, the effect of anti-wear and extreme pressure. For example, nitrogen-containing additives are mainly adsorbed on the surface of the friction pair to form protective film through chemical action. Borate is a semi-solid protective film with strong adhesive force developed on the friction surface. The extreme pressure anti-wear agent containing metal can produce a layer of protective film containing metal elements by displacement reaction between the surface of the friction pair and the metal of friction pair. This extreme pressure anti-wear effect has the advantage of no loss of friction pair metal, so it is called loss-free lubrication.ZDDP additives is a kind of excessive pressure, anti-wear, anti-friction, antioxidant, corrosion resistance and other excellent properties of grey type multifunctional oil additives, the thermal decomposition of mercaptan, sulfide, disulfide have extreme pressure anti-wear effect generated after polymer membrane, the longer the alkyl chain, the better the performance of anti-friction and anti-wear performance has the advantages of no replacement.

The Important Function of Lubricating Oil Additive

The additives containing sulfur, phosphorus, chlorine, and zinc will pollute the environment and corrode the metal during the preparation and use, which do not meet the requirements of green environmental protection. Nitrogen heterocyclic compounds, borates, and borates have not only excellent extreme pressure wear resistance but also the advantages of non-pollution of the environment and non-corrosion of metal, so they have extensive research and application value in the field of tribology.

Relatively more than the traditional extreme pressure anti-wear additive, rare earth materials, nanoparticles as a new research in recent years, more extreme pressure anti-wear agent, their poor solubility in lubricating oil, but can be used as the intense pressure anti-wear additives of lubricating grease, research shows that most of the rare earth oxides have excellent anti-friction and anti-wear properties at high temperature; The fluoride of lanthanum and cerium can effectively improve the extreme pressure and wear resistance of ester oil. Lanthanum fluoride can effectively prolong the wear life of the adhesive coating and increase the bearing capacity of grease. Thus it can be seen that rare earth materials have development space in the field of tribology.

The Nano oil additives

There are many different kinds of Nano oil additives and metal elemental, Nano non-metal main elemental (such as graphite, diamond, etc.), Nano metal compounds, Nano non-metal compound (such as graphite, graphene, PTFE, etc.), Nano rare earth compounds (LaF3, CeBO, CeO2), and magnetic nanoparticles (Fe3O4), etc. The dispersion and stability of nanoparticles in lubricating oil are the main factors limiting their application. Nano oil additives have anti-friction and anti-wear effect, many researchers think mainly because of the following: nanoparticles can and friction pair surface effect, form a protective film; It can act as a ball on the surface of friction pair and fill the pits on the surface of friction pair. Under the high load and the high heat generated by the friction process, the nanoparticles further penetrate the matrix of the friction pair to repair the damage, so that the friction surface is always in a smooth state.

Oil additives development direction

The combination of different types of additives will affect each other. When several additives are used in conjunction, we must pay attention to the effect of their combined use. In recent years, oil additives with environmental requirements and use requirements gradually improve, showing high performance, multi-function and the development trend of environment-friendly, therefore those who use narrow range, production of the single, chlorine-containing sulfur, phosphorus, and heavy metals additives will gradually be improved or replaced.

Extreme pressure anti-wear agents: heterocyclic nitrogen compounds and their derivatives, borates, rare earth compounds, nanoparticles, and ionic liquids have a broad development prospect. Ionic liquids have become a research hotspot in the field of tribology due to their excellent thermal stability, non-volatilization, and non-inflammability, a wide range of operating temperatures and designability of structure, etc.


Infomak is dedicated to the technology development of special oil additives, combined the Technology of nanomaterials developed dry lubricant and oil additives two series. Our products can significantly improve the performance of lubricating oil, improve energy efficiency, effectively protect the lubrication device and extend the oil change cycle, which can satisfy the lubrication oil constantly upgrading for high-end engine oil additives. Contact us.