CN1966509A - Organic molybdenum complex and its preparation method - Google Patents

Abstract

The invention relates to an organic molybdenum coordination compound and a preparation method thereof. The chemical name of the compound is tris(two-9-octadecene-1,6-adipamide) molybdenum, and the molecular weight is 1950. Good oil solubility as a lubricant additive and low tendency to discolor finished crankcase and engine oils. At the same time, as an additive, the compound of the invention has the characteristics of good bearing capacity, lubricating performance and high and low temperature performance. It has excellent anti-friction and anti-wear properties no matter at room temperature or high temperature, high or low load. The lubricating oil additive is suitable for the lubrication of various friction pairs, such as steel/steel, steel/copper, steel/aluminum, steel/ceramic, ceramic/ceramic, etc.

Description

A kind of organic molybdenum coordination compound and preparation method thereof

technical field

The invention relates to an organic molybdenum coordination compound and a preparation method thereof, which can be used as a lubricating oil additive.

technical background

With the development of the automobile industry and the aerospace industry, people have higher and higher requirements for lubricating oil. Simply improving the quality of oil products from the refining process can no longer meet the harsh conditions of high speed, high load, high vacuum and high and low temperature. Lubrication requirements for friction partners. Various additives must be added to the lubricating oil to improve the quality of the oil to meet the needs of the friction pair operation, so the quality of the lubricating oil depends on the quality and dosage of the additives.

It is known that molybdenum-containing additives can significantly improve various properties of lubricating oils. As an excellent solid lubricant and anti-extreme pressure additive, molybdenum disulfide (MoS ₂ ) has been used in oil for more than 50 years. Unfortunately, it is insoluble in oil and can only be used as a colloidal suspension, which greatly Limit the use of MoS ₂ in the field of lubrication. Therefore, in the late 1980s, some countries and regions such as the United States, Japan, the former Soviet Union and Western Europe increased their research on oil-soluble organic molybdenum compounds. These organic molybdenum compounds can form a stable phase system with base lubricating oils and greases, including molybdenum molybdenum molybdenum, molybdenum dimercaptothiazole, molybdenum alkylamine, molybdenum dialkylthiophosphate, molybdenum dialkylthiocarbamate, etc. Examples of lubricants that benefit from the addition of molybdenum are passenger car motor oils, heavy duty diesel engine oils, natural gas engine oils and locomotive oils. The use of molybdenum-containing additives for many years has proved that the correct use of molybdenum-containing lubricating oil additives can reduce the wear of friction partners, improve the anti-oxidation ability of lubricating oil, reduce the precipitation of additives in lubricating oil and save fuel. Numerous examples in the patent literature show the use of molybdenum-containing additives as antioxidants, precipitants, antiwear agents and friction modifiers. The following is a list of patents on molybdenum-containing lubricants:

USP4889647 USP4692256 USP5137647 USP5840672

USP5814587 USP5143633 USP4812246 USP5658862

USP5458807 USP5665684 USP4360438 USP4705641

USP4832867 USP5412130 EP1138752 EP0447916

Various oil-soluble molybdenum compounds and methods for their preparation are described in the aforementioned patents. For example, the molybdenum compound that Roman et al described in USP4889647 fatty oil, diethanolamine and molybdenum source reaction preparation; Aminoethanol prepares molybdenum-containing compounds, molybdenum trioxide-3,3-dioxacycloalkanes substituted with 2,4-heteroatoms in USP5412130; Alkylated amines, diols, and polyols to produce overbased molybdenum compounds.

At the same time, the existing organic molybdenum technology is plagued by many problems, which limits the wide application of organic molybdenum additives in the lubrication field. These issues include oil solubility, corrosion, color and cost.

Oil solubility: The compatibility of additives and base lubricating oil directly affects the range of use of additives. Although the compatibility of organic molybdenum compounds with base oil is greatly improved compared with MoS ₂ , from the current patent literature and use, many commercially available organic molybdenum additives used in lubricants have Limited solubility. In order to make molybdenum products more widely used in the lubricant field, the present invention is soluble in the amount of anti-wear and friction reducer in finished lubricants.

Corrosiveness: Molybdenum technology that appears in many patent documents contains elements such as sulfur and phosphorus. As we all know, long-term use of additives containing elements such as sulfur and phosphorus will corrode the friction pair, and the waste oil after use will also cause great pollution to the environment; at the same time, the phosphorus element in the additive will also cause The catalyst is poisoned and fails. Therefore, the development trend of high-quality lubricating oil additives is to reduce the sulfur and phosphorus content in finished oils, crankcase lubricants and engine lubricants as much as possible. Since these trends have already become a reality, there will be less need for lubricating oil additives containing sulfur and phosphorus in the future. It can be seen from the structural formula that the present invention does not contain sulfur and phosphorus elements.

Color: Molybdenum technology, which appears in many patent documents, can produce heavy color in crankcase lubricating oil even at moderate dosage, and this phenomenon can also appear in automobile engine lubricating oil. Therefore, a molybdenum source that does not change color is very important, because heavy color means that the oil is "used" to the intended user, and thus cannot provide maximum protection for the engine. Traditionally, the ASTM D 1500 color scale is used to determine the color of fully formulated crankcase and engine oils. There may be two types of unacceptable color, the first type of color change results in blackness on the D1500 color scale, the degree of blackening of acceptable finished lubricants depends on the user and field of use; generally speaking, a D 1500 equal to and greater than 5.0 Grades are not acceptable for finished crankcase and engine oils. The second type of discoloration has no "match" on the D 1500, these finished lubes are also very dark in addition to no match. Certain users will find these black crankcase and engine oils to be a difficult sell. The present invention itself is light black wax, if it is added in the base oil at 1wt%, the color of the base oil will not change much.

Cost: For a long time, molybdenum has been regarded as an expensive additive used in the crankcase and engine fields, and its high cost also limits its wide use in the automotive industry. Part of the reason for the high cost is that many commercially available molybdenum products have only a small amount of greater than 3 wt% molybdenum in the additive. There is a need to produce products with higher molybdenum content from lower cost raw materials.

The emergence of the above problems means that the molybdenum additives needed now must have high molybdenum content, no sulfur, phosphorus and other elements, good oil solubility, try not to change the color of the base oil, and have low cost. The sulfur-free, phosphorus-organic molybdenum complexes of the present invention have the above advantages without the problems associated with traditional molybdenum additives.

In one aspect the invention relates to sulfur, phosphorus free organomolybdenum complexes having good oil solubility and low tendency to discolor finished crankcase oils and engine oils. Such molybdenum additives include the reaction products of long chain diamides and molybdenum sources.

On the other hand, the present invention relates to a method for improving the oxidation resistance and tribological performance of base oil by adding the novel organic molybdenum complex additive without sulfur and phosphorus to the base lubricating oil.

Contents of the invention

The object of the present invention is to provide an organomolybdenum coordination compound, and at the same time investigate its tribological properties when added to liquid paraffin as a lubricating additive.

Another object of the present invention is to provide a method for preparing an organomolybdenum coordination compound.

The organomolybdenum complexes of the present invention include the reaction product of a long chain diamide and a molybdenum source. As a lubricating oil additive, it is used in the lubrication of automobile engines, the lubrication of various crankcase fields and the lubrication of various friction partners under harsh conditions.

An organic molybdenum coordination compound is characterized in that the molecular formula of the compound is such as formula (I),

(I)

The chemical name is tris(two-9-octadecene-1,6-adipamide) molybdenum, and the molecular weight is 1950.

A preparation method of an organic molybdenum coordination compound [three (two-9-octadecene-1,6-adipamide) molybdenum] is characterized in that the method comprises the following steps in sequence:

A. With 9-cis-18-alkenoic acid and 6-hexamethylenediamine, the friction ratio is 1:2, in a nitrogen atmosphere, 150 ± 5 ° C, dehydration reaction under stirring for 8-10 hours;

B, take toluene or water as water-carrying agent, be 1: 3～5 with the mol ratio of the reaction product of step A and molybdenum trioxide, nitrogen atmosphere, 160 ± 5 ℃, carry out dehydration reaction 6-8 hour under stirring, obtain The final target product is tris(di-9-octadecene-1,6-adipamide) molybdenum.

The specific equation of the preparation method of the present invention is as follows,

The preparation method of the compound involved in the present invention has a yield of 65-80%. Table 1 lists the physical properties of final product-three (two-9-octadecene-1,6-adipamide) molybdenum:

Table 1 Physical properties of tris(di-9-octadecene-1,6-adipamide) molybdenum physical state Kinematic viscosity (cSt) viscosity index Pour point (℃) Flash point (°C) Evaporation loss (wt%) ² 100°C 40℃ light black waxy 3.35 20.09 169 28 435 0.3

Compounds used as lubricating oil additives, the base oil can be selected from any synthetic oil, natural oil or mixture thereof, these oils are usually used in ignition or compression ignition internal combustion engines, such as natural gas engines, automobile, truck engines, ships and railway diesel engines crankcase lubricating oil. Synthetic base oils include dicarboxylic acids, polyglycols, polybutenes, alkyl esters of polyalphaolefins, and silicone oils. Natural base oils include paraffinic, naphthenic and unsaturated fatty acids.

When the present invention studies the tribological properties of the novel organic molybdenum coordination compound without sulfur and phosphorus, the selected base oil is paraffin, and the added amount of the lubricating additive of the present invention is 1 wt%.

The tribological performance of the lubricant of the present invention is evaluated by an Optimol SRV friction and wear testing machine, and the lubricating medium is paraffin and 1%MCC+paraffin respectively. The contact form of the friction pair is spherical-surface contact, the selected frequency is 25Hz, the amplitude is 1mm, the test time is 60min, and the test temperature is room temperature. The upper sample is a GCr15 (SAE52100) steel ball with a diameter of 10mm, and the lower sample is a 45# steel disc.

Table 2. Comparison of friction coefficients of steel/steel friction pairs lubricated by paraffin wax and the novel organic molybdenum complex without sulfur and phosphorus of the present invention 1wt%+paraffin wax 100N 150N 200N 300N Paraffin 1wt%MCC+paraffin 0.200.07 0.45 >10.15 0.11

Note: SRV is a fretting friction and wear testing machine. Test conditions: frequency 25Hz, amplitude 1mm, room temperature.

The results in Table 2 clearly show the good lubricating effect of the sulfur-free, phosphorus-organomolybdenum complexes of the present invention in steel/steel friction partners. Evidence is the dramatic drop in the coefficient of friction compared to lubricants without molybdenum.

The results in Table 3 clearly show the good anti-friction effect of the sulfur-free, phosphorus-organomolybdenum complex of the present invention in steel/steel friction partners. Evidence is the drastic decrease in the wear volume of the friction partners compared to lubricants without molybdenum.

Table 3. Comparison of wear of steel/steel friction pairs lubricated by paraffin wax and the new organic molybdenum complex without sulfur and phosphorus of the present invention 1wt%+paraffin wax 100N 150N 200N 300N Wear Volume (×10 ^-3 mm ³ ) (Paraffin) Wear Volume (×10 ^-3 mm ³ ) (1%MCC+Paraffin) 47.52.67 >100 5.80 9.74

In addition, the present invention investigates the tribological properties of the lubricating additive (MCC) that does not contain sulfur and phosphorus organic molybdenum coordination compounds at different temperatures on SRV. The contact form of the friction pair is spherical-surface contact, and the selected frequency is 25Hz, and the amplitude 1mm, the test time is 60min, and the test load is 100N. The upper sample is a GCr15 (SAE52100) steel ball with a diameter of 10 mm, and the lower sample is a GCr15 (SAE52100) steel disc.

Table 4. Comparison of friction coefficients of steel/steel friction pairs at different temperatures when lubricated by paraffin wax and the new type organic molybdenum complex without sulfur and phosphorus of the present invention 1wt% + paraffin wax 20°C 50℃ 100°C Paraffin (load is 100N) 1wt%MCC+paraffin (load is 100N) 0.120.09 0.140.09 0.180.09

The results in Table 4 clearly show the good temperature adaptability of the sulfur-free, phosphorus-organomolybdenum complexes of the present invention in steel/steel friction partners. The evidence is that the coefficient of friction of the friction partner remains essentially constant with temperature and is smaller than that of the lubricant without molybdenum.

Table 5 Comparison of friction coefficients of several friction pairs lubricated by paraffin wax and the new type organic molybdenum complex without sulfur and phosphorus of the present invention 1wt% + paraffin wax Friction pair ball/disk coefficient of friction 1wt%MCC+paraffin paraffin Steel/steel steel/aluminum steel/copper steel/ceramic ceramic/ceramic 0.0780.050.050.0800.073 0.150.1830.1620.1000.105

Note: SRV is a fretting friction and wear testing machine. Test conditions: frequency 25Hz, amplitude 1mm, load 50N, room temperature.

The results in Table 5 clearly show that the sulfur-free, phosphorus-organomolybdenum complex of the present invention has good adaptability to friction partners in steel/steel friction partners. The evidence is that the coefficient of friction of the friction partners shows a lower coefficient of friction in different kinds of friction partners compared to the lubricant without molybdenum.

The lubricant described in the invention has excellent bearing capacity, lubricating performance and high and low temperature performance. Suitable for lubrication of various friction pairs, such as steel/steel, steel/copper, steel/aluminum, steel/ceramic, ceramic/ceramic, etc.

Detailed ways:

Example 1

Add 1 mol of 1,6-hexamethylenediamine and 2 mol of cis-9-octadecenoic acid to a three-neck flask equipped with an intercalated thermometer, water separator, reflux condenser, nitrogen gas conduit and electromagnetic stirring, and pass nitrogen gas Stir for 10 minutes, heat up to 150°C (about 20 minutes), use toluene as water carrier, and reflux for 8-10 hours. Then add 0.5mol molybdenum trioxide to it, raise the temperature to 160°C, and reflux the reaction for 6-8h under the protection of _N2 . After the reaction mixture is cooled, filter, and then distill under reduced pressure to obtain organic molybdenum complex without sulfur and phosphorus. Compound - Molybdenum tris(di-9-octadecene-1,6-adipamide) (MCC). Yield 72wt%.

Example 2

The three-necked reaction flask was equipped with a magnetic stirrer, thermometer, reflux condenser and nitrogen inlet. Dry nitrogen flowed into the reactor through the inlet and out through the condensing reflux. Add 1mol of 1,6-hexamethylenediamine to the three-necked reaction flask, stir and heat to about 100°C with nitrogen gas, keep the reaction temperature at 100°C, and slowly add 2mol of cis-9-octadecenoic acid to the flask, and raise the temperature Heat to 150°C for 2h, add toluene within 2h, and remove the generated water by azeotropic distillation using a water separator. The reactant was cooled to 85±3°C, and 0.5mol molybdenum trioxide was added. The reaction was stirred vigorously to bring it to reflux temperature. Water was removed azeotropically over a period of 2 hours. After the reaction mixture was cooled, it was filtered and then distilled under reduced pressure to obtain an organomolybdenum coordination compound-tris(di-9-octadecene-1,6-hexanediamide) molybdenum (MCC) without sulfur and phosphorus. Yield 65wt%.

Claims (2)

1, a kind of organic molybdenum complex, the molecular formula that it is characterized in that compound be suc as formula (I),

Chemical name is three (two-9-vaccenic acid-1,6-adipamide) molybdenum, and molecular weight is 1950.

2, the preparation method of a kind of organic molybdenum complex [three (two-9-vaccenic acid-1,6-adipamide) molybdenum] is characterized in that this method may further comprise the steps successively:

A, with 9-cis-18-carbon enoic acid and 6-hexanediamine, friction ratio is 1: 2, in nitrogen atmosphere, 150 ± 5 ℃, carries out dehydration reaction 8-10 hour under stirring;

B, with toluene or water serve as the band aqua, with the reaction product of A step and the mol ratio of molybdic oxide is 1: 3～5, nitrogen atmosphere, 160 ± 5 ℃ carried out dehydration reaction 6-8 hour under stirring, and obtained final purpose product three (two-9-vaccenic acid-1,6-adipamide) molybdenum.