Reducing the friction and wear of the main friction pairs of mechanical equipment, reducing energy consumption and reducing environmental pollution are the three major issues facing the design, manufacturing, and use of modern machinery. Lubricants are the key factors. Extreme pressure additive and anti-wear additive are the most commonly used lubricant additives. Under the action of pressure, adding intense pressure anti-wear agents to the lubricant can reduce the friction, wear, and sintering of mechanical parts, make the machine lubricate, thereby improving the working efficiency of the engine and extending the service life of the device. Traditional extreme pressure anti-wear additives usually contain sulfur, phosphorus, and organometallic salts, while new intense pressure anti-wear additives are developing towards ashless, low phosphorus, and low sulfur.

Research and application status of various extreme pressure additive and anti-wear additive

1. Phosphorous extreme pressure additive

Phosphorus-containing organic compound additives have been used as extreme pressure anti-wear additives for a long time, and have obtained a wide range of industrial applications. They are currently one of the most widely used additives with the best anti-wear effects. There are many types of phosphorus extreme pressure additive and anti-wear additive. According to their active elements, they can be divided into phosphorus type, phosphorus nitrogen type, sulfur phosphorus type, sulfur phosphorus nitrogen type, and sulfur phosphorus nitrogen boron type. Phosphorus anti-wear agents have been around for a long time, mainly in phosphate and phosphite series.

2. Nitrogen-containing heterocyclic extreme pressure additive and anti-wear additive

Nitrogen-containing heterocyclic compounds and their derivatives have excellent anti-wear properties, anti-oxidation properties, dispersive properties, rust-proof properties, and anti-corrosive properties. They have been the focus of research in the field of tribology in recent years. Nitrogen heterocyclic additives are divided into: thiazole derivatives, thiadiazole derivatives, oxazolines, benzotriazole derivatives, imidazoline derivatives, pyridine and imidazoline derivatives, diazine derivatives, and triazine derivatives, etc.

3. Boron-containing extreme pressure additive and anti-wear additive

As a new type of non-reactive extreme-pressure anti-wear additive, boron-based additives are receiving more and more attention due to their unique chemical stability. From chemical structure, boron-based additives can be divided into organic borate and inorganic borate. The boron-containing additives not only have excellent thermal oxidation stability and sealing adaptability, have no corrosion effect on copper at high temperature, and have a good impact on steel. Excellent anti-rust performance, at the same time it is conducive to improving the operating environment, has the excellent load-carrying capacity, and anti-friction and anti-wear performance are superior to sulfur and phosphorus additives, has been used in industrial gear oil, two-stroke oil.

The boron-based additives with broad development prospects are organic borate esters. A large number of studies have found that almost all of the organic borate esters have friction reduction and oxidation resistance, and some have anti-wear effects. Besides, its thermal stability is excellent, and it does not corrode copper at high temperatures, has excellent rust resistance to steel, and also has good sealing adaptability, non-toxic and odorless, and conducive to environmental protection. These advantages are incomparable with traditional phosphorus and sulfur extreme pressure anti-wear additives.

4. Organometallic salts extreme pressure additive and anti-wear additive

Organometallic salts are an essential class of lubricating oil additives, which are widely used. According to the structural characteristics of the compounds, the organometallic salts extreme pressure anti-wear additives can be divided into the following categories: 1) metal dialkyl dithiocarbamates, 2) dialkyl dithiophosphate, 3) Polymers containing active metal elements (mainly EDTA water-soluble metal complexes). However, in recent years, environmental regulations have become increasingly stringent, and the demand for ashless lubricant additives has been increasing. Therefore, lubricant additives containing metal elements are increasingly challenged.

ZDDP oil additive has many functions such as anti-oxidation, anti-corrosion, extreme pressure, anti-wear, and so on. Since the middle of the 20th century, it has been an indispensable additive component in oils such as internal combustion engine oils and widely used in petroleum.

Organic molybdenum has excellent tribological properties and occupies a significant position in lubricating materials. Organic molybdenum-based additives have various functions such as anti-wear, anti-friction, extreme pressure, and anti-oxidation, which have attracted full attention from academia and industry. Experiments show that MoDTC has good intense pressure anti-wear performance, especially ZDDP shows a perfect anti-wear synergy effect.

5. Nano oil additive

With the rapid development of nanotechnology and surface analysis technology, many scholars expect to use nanoparticles as a breakthrough in the event of new lubricant additives. Nanomaterials used as additives for lubricants are mainly of the following categories: (1) layered inorganic substances such as graphite, MoS2, etc .; (2) nano soft metals such as Cu, Al, Ni, etc .; (3) nano Oxides, such as Al2O3, ZnO, etc .; (4) compounds containing active element S, such as PbS, ZnS, etc .; (5) inorganic borate salts, such as Cu3 (BO3) 2, Ni3 (BO3) 2, etc .; (6) Rare earth compounds, such as rare earth fluoride LaF3, rare earth oxide La2O3, CeO2, and rare earth hydroxide La (OH) 3. Unique earth compounds have great potential for development as lubricant additives. They have the advantages of high-temperature resistance, good oil solubility, and low pollution. Therefore, new multifunctional rare earth organic sophisticated additives have been continuously developed.

With the increase of people's awareness of environmental protection and the increasingly stringent environmental regulations, the development trend of new extreme pressure anti-wear additives in the future is as follows: 

(1) Without reducing the excessive pressure anti-wear performance, improve its thermal oxidation stability and reduce Phosphorus consumption to extend its service life is the development direction of extreme phosphorus pressure anti-wear agents;

(2) To find out the compounding rule and mechanism of other absolute pressure anti-wear agents, and to develop a boron-containing agent with hydrolytic stability is the development direction of intense boron pressure anti-wear agents;

 (3) Application of green synthesis method to obtain multifunctional nitrogen-containing heterocyclic derivative lubricant additives with high yield, low cost, and ideal effects; meanwhile, in-depth research on its friction mechanism using new characterization methods is nitrogen-containing heterocyclic The development direction of ring lubricant additives;

(4) As an emerging technology, the nano oil additive solves its agglomeration and cost problems, and research on the compounding rule with conventional additives in lubricating oil is the development direction of nanoparticle extreme pressure anti-wear agents.

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.