What is molybdenum disulfide MoS2?

Molybdenum disulfide is an inorganic substance with the chemical formula MoS2, which is the main component of molybdenite. Black solid powder with metallic luster. The melting point is 2375℃, the density is 4.80g/cm³ (14℃), and the Mohs hardness is 1.0～1.5.

Uses of molybdenum disulfide MoS2

Molybdenum disulfide is an important solid lubricant, especially suitable for high temperature and high pressure. It is also diamagnetic, can be used as a linear photoconductor and a semiconductor showing P-type or N-type conductivity, and has the functions of rectification and energy conversion. Molybdenum disulfide can also be used as a catalyst for the dehydrogenation of complex hydrocarbons.

Molybdenum disulfide is also known as the "king of advanced solid lubricants." Molybdenum disulfide is a solid powder made by chemically purifying natural molybdenum concentrate and changing the molecular structure. The color of this product is black with silvery gray, metallic luster, slippery to the touch, and insoluble in water. The product has the advantages of good dispersibility and non-sticking. It can be added to various greases to form a non-sticky colloidal state, which can increase the lubricity and extreme pressure of the grease. It is also suitable for high-temperature, high-pressure, high-speed and high-load mechanical working conditions to extend the life of the equipment.

The main function of molybdenum disulfide used in friction materials is to reduce friction at low temperatures, increase friction at high temperatures, and have a small loss on ignition. It is volatile in friction materials.

Anti-friction: Molybdenum disulfide processed by supersonic jet pulverization has a particle size of 325-2500 mesh, micro-particle hardness of 1-1.5, and friction coefficient of 0.05-0.1, so it can reduce friction when used in friction materials;

Increase friction: Molybdenum disulfide is not conductive, and there are copolymers of molybdenum disulfide, molybdenum trisulfide and molybdenum trioxide. When the temperature of the friction material rises sharply due to friction, the molybdenum trioxide particles in the copolymer expand with the temperature, which plays a role in increasing friction;

Anti-oxidation: Molybdenum disulfide is obtained through chemical purification and comprehensive reaction. Its PH value is 7-8, which is slightly alkaline. It covers the surface of the friction material to protect other materials from oxidation, especially to make other materials not easy to fall off, and the adhesion force is enhanced;

Parameters of molybdenum disilicide

Fineness: 325 mesh -2500 mesh;

PH value: 7-8;

Density: 4.8-5.0g/cm3;

Hardness: 1-1.5;

Loss on ignition: 18-22%;

Coefficient of friction: 0.05-0.09.

In addition, molybdenum disulfide can also become a new material for making transistors. Compared with graphene, which is also a two-dimensional material, molybdenum disulfide has an energy band gap of 1.8 eV, while graphene does not have an energy band gap. Therefore, molybdenum disulfide may have a very broad application space in the field of nano-transistors. Moreover, the electron mobility of a single-layer molybdenum disulfide transistor can reach up to about 500 cm^2/(V·s), and the current switching rate can reach 1×10^8.

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.

The most obvious feature of molybdenum disulfide grease is that the appearance is black, and it cannot be adjusted to other colors, because it is a lithium-based grease with additives such as molybdenum disulfide MoS2; but it is not a black grease. The grease that contains molybdenum disulfide may also be graphite-containing grease; so many people will confuse molybdenum disulfide grease with graphite grease.

So what is the difference between these two greases?

Molybdenum disulfide grease is a cost-effective high and low temperature synthetic grease made of low-viscosity PAO and molybdenum disulfide. It has the effect of anti-wear and extreme pressure, can carry heavy loads, and also has good thermal stability and lubrication. It has good compatibility with most plastics, effectively reduces the noise from plastic gears, has a long service life, and has low seepage.

Graphite grease is a kind of graphite grease made from synthetic oils thickened by inorganic thickeners and added with ultra-fine graphite powder, anti-oxidation, anti-corrosion and other additives. This ultra-high temperature grease will slowly volatilize the base oil when the temperature is above 200℃, and graphite will adhere to the lubricating surface to form solid lubrication. It is specially used for the lubrication of high temperature friction parts and bearings under heavy load/impact load or humid/polluted environment. Maximum rust and corrosion protection.

As explained above, although molybdenum disulfide and graphite are the same additives as grease, graphite grease mainly has outstanding high temperature performance, while molybdenum disulfide grease has outstanding anti-wear and extreme pressure performance, and graphite grease has two advantages Not as good as molybdenum disulfide grease.

Performance characteristics of molybdenum disulfide high and low temperature grease

Outstanding extreme pressure resistance, anti-vibration performance and wear resistance, strong load-bearing capacity;

Excellent lubricity, adhesion, corrosion resistance, water resistance and moisture resistance;

Good high temperature and low temperature resistance, no dilution or burning-out phenomenon at high temperature;

Excellent oxidation resistance, particularly low evaporation loss and a long service life.

Used for rollers and bearings that work under high temperature, high load or severe cold conditions, hot fan bearings, high temperature conveyor belt bearings, high temperature bearings for textile machines, high pressure roller presses, moving guide grooves, universal joints, spline shafts, screw rods lubricating.

It is used for the lubrication of heavy-duty gears, turbines and vortex rods in clearance operation.

Used for lubrication of high-load friction parts such as automobile chassis, steering system rack and pinion, and slot structure.

Used for the lubrication of high-load parts of industrial equipment (threads, screw caps, bushings, fasteners, couplings, shaft pins of transmission belts).

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.

People who love cars know that the safe operation of the car and the long service life of each component, in addition to the hard enough supporting equipment, the later use habits and car maintenance are also very important. As people change and improve the concept of car maintenance, lubricants are becoming more and more important in car maintenance. Using car lubricants well, or saving more than 10% of the fuel, can extend the life of the machine by 2-3 times, and drive Safer on the road.

How to choose lubricants?

Choosing a good lubricant is like choosing a skin care product that suits you. It is necessary to match and select in strict accordance with the requirements for different vehicle engine types and different vehicle conditions. However, there are many fakes in the market, blind obedience of the public, and low cost performance.

R&D by using graphene and introducing advanced technology

Graphene, known as "black gold", "king of new materials", graphene's unique penetration technology, few-layer graphene sheet friction and excellent thermal conductivity, can effectively solve the problem of automobile engine burning oil, blue smoke, etc. Problem, repair engine wear and tear, steadily increase engine power, reduce engine vibration and noise, save fuel, and reduce vehicle exhaust and other harmful gas emissions.

Graphene can keep the lubricant in good working condition for a longer period of time. In the high temperature and high pressure environment, the penetration phenomenon occurs, and the engine is coated with a layer of graphene film, thereby forming a double film protection of the graphene film and the oil film. Better protect the engine, improve power, reduce fuel consumption by 5%-10%, significantly reduce exhaust emissions and extend engine life.

At the same time, graphene lubricating oil has super anti-wear and self-repairing properties, which effectively solves the wear and tear of parts caused by cold start, and can more effectively solve vehicle failures caused by engine wear.

The development of the automobile industry has a big market prospect

Take the total number of automobiles in China as an example. As of 2020, the total number of automobiles in China has exceeded 320 million, and it will increase at a rate of 10% every year. In the next few decades, it will bring huge lubricants to the automotive lubricant market. Consumption potential, according to the development trend of China's lubricant market, experts predict that China's annual demand for gasoline and engine oil will grow at a rate of 10%. Lubricating oil is a rigid demand, and the market prospect is definitely broad. We can calculate it like this. If a city has a population of 800,000 and a total of 150,000 cars, the average annual maintenance is 2 times, and the maintenance cost is about 50 US dollars. The company’s sales can reach at least US$20 million.

The graphene lubricating oil, which uses advanced technology with new materials, is not only a successful attempt of new graphene materials in the field of lubricating oils, but also a high-profile energy-saving and environmentally friendly product with its outstanding performance.

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.

What is molybdenum disulfide ?

Molybdenum disulfide is the main component of molybdenite. Black solid powder with metallic luster. The chemical formula is MoS2, the melting point is 1185℃, the density is 4.80g/cm (14℃), and the Mohs hardness is 1.0-1.5.

Molybdenum disulfide lubrication mechanism

Molybdenum disulfide can be adsorbed on the metal surface (note that the metal is mentioned here, and PTFE is generally used for plastics) to form a lubricating film, which plays a role in lubricating when the lubricant film is broken.

Molybdenum disulfide adheres to the friction pair with the lubricant and forms a stronger connection (chemical affinity or physical embedding) than the lubricant.

Features of molybdenum disulfide

When used in a humid environment, molybdenum disulfide may cause electrochemical corrosion of the metal. In a low-temperature and humid environment, the performance of molybdenum disulfide will be affected.

Graphite can also be used as a solid additive, but compared with graphite, the friction coefficient of molybdenum disulfide is much smaller than graphite, so the frictional resistance caused is smaller. At high temperatures, molybdenum disulfide will oxidize to form molybdenum trioxide, which does not have lubricity.

Under dry, high temperature and vacuum conditions, the performance of molybdenum disulfide can be fully utilized.

In the presence of a high concentration of oxygen, the oxidation rate of molybdenum disulfide increases and becomes molybdenum trioxide. In the air, below 300℃, the oxidation rate of molybdenum disulfide is very slow and its properties are very stable. Above 400 degrees Celsius, molybdenum disulfide slowly begins to oxidize to form molybdenum trioxide. After that, the higher the temperature, the more serious the degree of oxidation and the rate of oxidation, reaching about 600 degrees Celsius, and the rapid oxidation of molybdenum disulfide in the air. In addition to humidity and temperature, particle size also affects the oxidation rate of molybdenum disulfide. Under the same conditions, the finer the powder, the faster the oxidation rate. Although molybdenum trisulfide does not have lubricity, it will not cause obvious wear on the metal friction surface. Therefore, after molybdenum disulfide is partially oxidized to molybdenum trisulfide, it can still maintain a certain degree of lubricating performance.

Molybdenum disulfide begins to decompose at 1370℃, with a melting point of 1700℃.

In environments with high humidity and water contact, molybdenum disulfide can cause metal corrosion. The use of additives can inhibit corrosion to a certain extent. However, if the lubricating surface is subjected to extremely high pressure, the performance of anti-corrosion additives may also fail.

Although molybdenum disulfide itself is a lubricant, it is a solid after all. Adding to the grease will reduce the smoothness of the grease and increase friction to a certain extent. Therefore, for general load equipment, if it is not necessary or specified to require molybdenum disulfide lubricating oil (extreme pressure lubricating oil/grease), it is not recommended to use it. Molybdenum disulfide is suitable for heavy loads and low speeds, resulting in a large amount of boundary lubrication.

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.

Although oil additives only account for 1% to 20% of lubricating oil ingredients, it is precisely because of the existence of oil additives that the performance of the lubricating oil can be improved in a certain aspect, thereby obtaining the desired effect.

What is oil additives?

Oil additives: Compounds used to improve the performance of lubricating oils by adding a small amount of ingredients.

Common oil additives include: detergents and dispersants, antioxidants, anticorrosives, pour point depressants, antifoams, rust inhibitors, viscosity index improvers, etc.

Viscosity index improvers are the leading products of lubricant additives, accounting for approximately 25.2% of the entire market share in 2020.

Reasons for the emergence of Oil additives:

With the continuous development of the machinery industry and the increasingly stringent environmental requirements, the requirements for the performance of lubricants are also getting higher and higher, which forces the production of additives.

In order to improve the performance of lubricants, in addition to further improving the quality of the base oil, the use and improvement of additives are also indispensable.

The role of oil additives:

1. Give lubricants new properties;

2. Strengthen the performance of base oil;

3. Slow down the speed of bad changes in lubricating oil.

Types of oil additives

1. Additives that improve the physical properties of base oils, such as viscosity index improvers, anti-foaming agents, pour point depressants, etc.;

2. Additives to protect the lubricated surface, such as anti-corrosion agent, anti-rust agent, anti-wear agent, detergent and dispersant, etc.;

3. Additives to protect lubricating oil, such as antioxidants.

In order to improve performance, at least one oil additive is added to the current lubricants, and some lubricants contain more than ten kinds of oil additives. Such as detergents, which can be used to solubilize polar substances, neutralize acidic substances in lubricating oils, and make some lubricating oils have antioxidant properties; dispersants can prevent the formation of sludge, keep the engine clean, and correct the accumulation of soot. .

Global oil additives market

The oil additives market can be divided into four categories:

1. Deposition control additives;

2. Viscosity control additives;

3. Film-forming additives;

4. Other lubricant additives.

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.

Graphite is a traditional solid lubricating material. Due to its special layered crystal structure, graphite material has good lubricating properties. As early as the 1950s, many graphite lubrication products have been developed one after another. For example, the world-famous Leica camera made in Germany used graphite powder as the lubricating material for mechanical parts. In the 1960s, my country also produced bronze oil-impregnated graphite bearings. In recent years, the domestic "Chikai" brand of energy-saving antifriction king additives and "Medron" series lubricants have also come out. Many studies and practices have shown that graphite used in lubricating oil has huge economic benefits and has many advantages of its own. With the development of science and technology and the deepening of scientific research, graphite lubricating materials have been extended to appear in the form of graphite derivatives, such as flake nano graphite, expanded graphite, fluorinated graphite, and elemental or compound intercalated graphite. This article comprehensively discusses the types, dispersion stability and lubricating effect of graphite lubricant additives, and provides references for the development and application of new graphite lubricant materials.

Influencing factors of graphite lubrication effect

Graphite particle size

The lubrication performance of graphite is affected by the particle size. Some scholars have shown that graphite powder with an average particle size of 4~5μm will produce a good lubricating effect, which can minimize the friction and wear of the specimen. However, more scholars have shown that controlling the average particle size below 0.5 µm is the key to the stable suspension of graphite in lubricating oil and also the condition for exerting lubricating performance. Graphite particles are too large to enter between the friction pairs, and cannot isolate and hinder the contact between the two friction surfaces, thus affecting the lubrication performance. However, it is obvious that if the graphite particles are too small to severely damage the graphite layered crystal structure, the friction reduction mechanism of the graphite sheet slip will also be lost, and the graphite lubrication effect is also poor. Therefore, the proper size of graphite particles is the key to graphite's lubricating effect.

The structure of graphite

The structure of graphite is one of the factors affecting the lubricating effect of graphite. Different graphite structures determine different types of graphite. It has not been reported so far that the lubricating effect of expanded graphite, fluorinated graphite, graphite intercalation compound and flake nano-graphite has been compared. It can be seen that under the condition of proper graphite particle size, different graphite types have their own optimal lubricating environment, which is difficult to compare. For example, expanded graphite has a strong absorption capacity and enrichment effect, and it can be mixed with extreme pressure additives to achieve the best effect; when the F/C ratio of fluorinated graphite reaches 1.0, the wear resistance life reaches the best value; and the temperature determines the graphite intercalation The degree of deintercalation of the compound; some scholars have pointed out that as the graphite diameter-to-thickness ratio increases, the specific wear of the lubricated material decreases significantly. It can be seen that the diameter-to-thickness ratio affects the lubricating effect of flake nano-graphite.

External environment

The particle size and structure of graphite are the internal factors that determine the lubricating effect of graphite, and the external environment is the external cause of the lubricating effect of graphite. As early as the 1940s, Robert proposed that humidity is an important factor affecting the lubrication effect of graphite. Water vapor and other small molecules can adsorb on the crystal edges of graphite and invade along the dissociation surface (interlayer), thereby reducing the surface energy of the graphite layer. It makes it easier for graphite to adsorb and form a film on the friction surface, thereby improving the lubricating effect. Bowden et al. also proposed that the friction coefficient of graphite under vacuum conditions increased significantly. Once air was introduced, the friction coefficient decreased rapidly. Therefore, improving the environmental medium of graphite-based lubricating materials is also the key to more effective graphite lubricity. Graphite and graphite derivatives have been widely used in lubricating oil additives and other lubrication fields due to their own good lubrication advantages. However, it is worth noting that the preparation process of ultra-fine and high-purity graphite still requires technological breakthroughs. Graphite nanoization and high-purity industrial production of graphite without sulfur and chlorine will be the future development trend of graphite; at the same time, with the development of technology, the development of new graphite derivative materials such as hollow nanometer will also provide excellent graphite lubrication The agent provides the material basis. It is believed that new graphite lubricating materials will continue to play a more important role for industrial lubrication.

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.

Although additives only account for 1% to 20% of the lubricating oil composition, it is precisely because of the presence of additives that the performance of the lubricating oil in a certain aspect is improved, thereby obtaining the desired effect.

What are lubricant additives?

Additives: Compounds used to improve the performance of lubricating oils by adding a small amount of ingredients.

Common additives are: detergents and dispersants, antioxidants, anticorrosives, pour point depressants, antifoaming agents, rust inhibitors, viscosity index improvers, etc.

Viscosity index improvers are the leading products of lubricant additives, accounting for approximately 23.3% of the entire market share in 2015.

Reasons for the appearance of additives:

With the continuous development of the machinery industry and the increasingly stringent environmental requirements, the requirements for the performance of lubricants are also getting higher and higher, which forces the production of additives.

In order to improve the performance of lubricants, in addition to further improving the quality of the base oil, the use and improvement of additives are also indispensable.

The role of oil additives:

1. Give lubricants new properties;

2. Strengthen the performance of base oil;

3. Slow down the speed of bad changes in lubricating oil.

Types of oil additives

1. Additives that improve the physical properties of base oils, such as viscosity index improvers, anti-foaming agents, pour point depressants, etc.;

2. Additives to protect the lubricated surface, such as anti-corrosion agent, anti-rust agent, anti-wear agent, detergent and dispersant, etc.;

3. Additives to protect lubricating oil, such as antioxidants.

In order to improve performance, at least one additive is added to current lubricants, and some lubricants contain more than ten kinds of additives. Such as detergents, which can be used to solubilize polar substances, neutralize acidic substances in lubricating oils, and make some lubricating oils have antioxidant properties; dispersants can prevent the formation of sludge, keep the engine clean, and correct the accumulation of soot. .

Global lubricant oil additives market

The additive market can be divided into four categories:

1. Deposition control additives;

2. Viscosity control additives;

3. Film-forming additives;

4. Other lubricant additives.

Four major international oil additive companies:

Lubrizol (Lubrizol), Infineum (Infineum), Chevron (Chevron Oronite), Afton (Afton)

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.

What are the ingredients of lubricating oil?

Lubricating oil generally consists of two parts: base oil and additives. Base oil is the main component of lubricating oil and determines the basic properties of lubricating oil. Additives can make up for and improve the performance of base oils and give some new properties. It is an important part of lubricating oil.

Lubricating oil base oil is mainly divided into three categories: mineral base oil, synthetic base oil and biological base oil. Mineral base oils are widely used and used in a large amount (about 95% or more). However, in some applications, synthetic base oils and bio-oil base oils must be used for blending products, so these two base oils have developed rapidly.

Mineral oil base oil is refined from crude oil. The main production processes of lubricating base oil include: atmospheric and vacuum distillation, solvent deasphalting, solvent refining, solvent dewaxing, clay or hydrogenation supplement refining.

The chemical composition of mineral base oils includes high boiling point, high molecular weight hydrocarbons and non-hydrocarbon mixtures. Its composition is generally alkane (straight chain, branched chain, multi-branched chain), cycloalkane (monocyclic, bicyclic, polycyclic), aromatic hydrocarbon (monocyclic aromatic hydrocarbon, polycyclic aromatic hydrocarbon), cycloalkyl aromatic hydrocarbon and oxygen-containing, nitrogen-containing , Sulfur-containing organic compounds and non-hydrocarbon compounds such as gums and asphaltenes. Biological base oil (vegetable oil) is becoming more and more popular, it can be biodegraded and quickly reduce environmental pollution. Synthetic lubricating oil has the characteristics of excellent low temperature performance, good lubrication performance and long service life. It can be suitable for environments such as high load, high speed, high vacuum, high energy radiation and strong oxidizing media. Since all industrial companies in the world are seeking measures to reduce environmental pollution, and this "natural" lubricant has this feature, although the cost of vegetable oil is high, the increased cost is enough to offset the use of other mineral oils and synthetic lubricants Environmental governance costs caused by oil. According to the nature and processing technology of crude oil, it is classified into paraffin base oil, intermediate base oil and naphthenic base oil.

Why do lubricants need additives?

Lubricating oil base oil possesses some basic characteristics and performance of lubricating oil, but only relying on general processing technology to improve lubricating oil cannot produce lubricating oil with various properties that meet the requirements of use. In order to make up for the defects of certain properties of lubricating oil and give lubricating oil some new excellent properties, various additives with different functions are added to the lubricating oil. The addition amount ranges from a few parts per million to tens of percent.

Adding additives to lubricating oil has two main functions: one is to change the physical properties of the lubricating oil, such as viscosity, freezing point, etc.; the other is to increase or enhance the chemical properties of the lubricating oil, such as anti-oxidation and anti-corrosion. The use of additives in lubricating oil not only meets the requirements of various new machinery and engines, but also prolongs the service life of lubricating oil, reducing the demand for lubricating oil in the proportion of petroleum products.

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.