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A brief discussion on the cleaning agent of lubricating oil additive

With the development of industrial technology, modern equipment requirements of high speed, high performance, high automation, high efficiency and long life, in terms of lubrication simply with mineral oil lubrication materials has been difficult to meet. Adding a small amount of other substances to a lubricating material can improve its performance, give it new characteristics, to meet the increasingly harsh use environment, these substances are called lubricating oil additives.

Main function and classification of dispersant lubricant additive （2）

The oil soluble group provided by the dispersant is larger than the purifier, which can effectively prevent the accumulation of carbon and colloidal material together.

Main function and classification of dispersant lubricant additive   （1）

In the early stage, the widely used detergent dispersants in internal combustion engine oil are metallic sulfonates, alkyl phenols, phosphonates and alkyl salicylate, which are called metal detergent dispersants. Subsequently developed a metal-free additive, it has excellent dispersion properties, in order to distinguish from the former, people called it ash-free powder.

viscosity index improver

The effect of viscosity index improver on the fuel economy of gasoline engine oil. The high frequency reciprocating tester was used to simulate the friction of the engine, and the lubrication performance of gasoline engine oil was investigated by measuring the friction factor. The smaller the friction factor of gasoline engine oil, the better the lubricating performance and the more conducive to improving fuel economy. The friction torque of gasoline engine oil was measured by engine drag test and compared with the friction torque of reference oil. The greater the torque difference (torque difference = the average value of the friction torque of the reference oil - the friction torque of the gasoline engine oil), the better the fuel economy of the gasoline engine oil. The friction coefficient of gasoline engine oil of 0W-20 viscosity grade prepared with polymethacrylate with smaller kinematic viscosity (kinematic viscosity at 100 ℃ of 890 mm2/s) and better shear stability (shear stability index 5) is higher than that of gasoline engine oil. Small, large torque difference, with better fuel economy. According to NEDC (New European Driving Cycle) simulation cycle test fuel consumption calculation, it can improve fuel economy by 0.28%. According to the "Passenger Vehicle Fuel Consumption Limits" issued by the Ministry of Industry and Information Technology: GB16578-2014 and "Passenger Vehicle Fuel Consumption Evaluation Methods and Indicators": GB27999-2014 mandatory standards, by 2020, all passenger vehicles will be The average fuel consumption of 100km must be reduced to 5.0L, so saving fuel and reducing fuel consumption is the general trend of the current automobile industry development. In order to reduce fuel consumption and improve fuel economy, in addition to improving the design of the engine, it is also an effective way to improve the lubrication state between the friction parts of the engine. Generally speaking, during the operation of the engine, the bearing parts are mainly in the state of elastic fluid lubrication, while the parts such as the valve train, piston and cylinder liner are mainly in the state of boundary lubrication and mixed lubrication. For fluid lubrication state, choosing low-viscosity gasoline engine oil can reduce friction loss; for boundary lubrication state, adding friction modifier to engine oil is a more effective method to reduce friction loss. For the mixed lubrication state, it is necessary to comprehensively consider the optimization of the viscosity characteristics and friction characteristics of gasoline engine oil. In order to improve the fuel economy of passenger cars, it is necessary to study the effect of gasoline engine oil components on fuel economy. As an additive that can improve the viscosity-temperature properties of lubricating oils, viscosity index improvers have been widely used in engine oils. Commonly used viscosity index improvers are hydrogenated styrene diene copolymer (HSD for short), olefin copolymer (OCP for short), polymethacrylate (PMA for short), hydrogenated styrene-isoprene copolymer (SDC) And polyisobutylene (PIB) etc. The overall performance of OCP and HSD is better, but HSD has better shear resistance than OCP, and is more commonly used in high-grade gasoline engine oil. PMA has the characteristics of improving the low temperature performance of gasoline engine oil and increasing the viscosity index, and is also widely used in high performance gasoline engine oil. Some studies have reported that gasoline oil formulated with PMA viscosity index improver helps to form a boundary oil film on the metal surface under high temperature and low speed conditions, thereby significantly reducing friction and improving the fuel economy of gasoline oil.

Propylene chemical properties

The chemical properties of propylene are determined by its double bond and the hydrogen atom on the allyl group. In the molecular structure of propylene, only the projection on the main plane shows a low degree of symmetry, making it the smallest stable-state unsaturated hydrocarbon. This asymmetry is also manifested in the dipole moment of propylene is only 0.35D, which is prone to various types of chemical reactions. The carbon atoms at position 1 and 2 are the same as the molecular structure of ethylene. On the same triangular plane, they cannot rotate freely due to the existence of double bonds. The carbon atom at position 3 is in a tetrahedron like methane and can rotate freely. The hydrogen atom on it is attracted by the carbon atom. The hydrogen atom on the allyl group is the main reason that makes its chemical properties different from ethylene. Propylene molecules can undergo self-addition reactions. When phosphoric acid, boron fluoride or sulfuric acid are used as catalysts on solids, the reaction proceeds according to the carbanion mechanism. At low temperatures, the main product of propylene dimerization is 4-methyl- 2-pentene. For example, alkyl alkali metal and certain alkali metal compounds are used as catalysts to dimerize propylene. The reaction proceeds in the direction of carbanion, and the product is mainly 4-methyl-1-pentene. Due to the asymmetry of the propylene molecule, the displacement of the double bond and the conversion of the cis-trans structure at the same time, the product composition may include various hexene isomers and olefins above C6. C6 olefins can be used as raw materials for synthetic polymers, gasoline blending agents, etc. [4]. Propylene is oligomerized on an acid catalyst to produce nonene and dodecene. When propylene is co-oligomerized with a mixture of butene, the polymer contains a large amount of heptene. Using aluminum alkyl and titanium trichloride as catalysts or metallocene and methylaluminoxane as catalysts, propylene polymerization is carried out in bulk, emulsion or gas phase at a certain temperature and pressure to obtain polypropylene.

Key points of methanol fire fighting

Mainly include: alcohol-resistant foam, dry powder, carbon dioxide, sand and so on. Fire fighting method: Move the container from the fire scene to an open place as much as possible. Spray water to keep the fire container cool until the end of the fire extinguishing. If the container in the fire scene has changed color or produces sound from the safety relief device, it must be evacuated immediately.