CN113388434B - Extreme pressure antiwear agent composition, extreme pressure antiwear agent and space lubricant - Google Patents

Abstract

The present invention provides an extreme pressure antiwear agent composition, an extreme pressure antiwear agent and a space lubricant using the extreme pressure antiwear agent, wherein the extreme pressure antiwear agent composition comprises a naphthenate and a diluent, wherein The diluent is polyalkylcyclopentane, and the general formula of polyalkylcyclopentane is shown in formula I; wherein, R ¹ is a normal or isomeric alkyl group of C ₅ to C ₂₄ , and n is a group of 2 to 4 Positive integer; naphthenic acid salt is prepared by reacting naphthenic acid and metal salt, and the average relative molecular mass of naphthenic acid is 170-300. The extreme pressure antiwear agent provided by the invention has excellent solubility and low temperature stability in the space lubricant base oil polyalkylcyclopentane, has excellent low volatility characteristics, can meet the low volatility requirements of space lubricants, and has Good prospects for space lubrication applications.

Description

Extreme pressure antiwear composition, extreme pressure antiwear and space lubricant

technical field

The invention relates to the field of lubricants, in particular to an extreme pressure antiwear agent composition and a preparation method thereof.

Background technique

Space lubricants are mainly used for the lubrication of moving parts of space devices. Due to the high vacuum space environment, they need to have excellent low volatility characteristics and lubricating properties to ensure long-term stable operation of lubricated parts. Polyalkylcyclopentane has extremely low volatility and saturated vapor pressure, good viscosity-temperature properties and lubricating properties, and is an ideal base oil for space lubricants. The volatility of lead naphthenate is less than that of phosphate ester type extreme pressure antiwear agent, and it has good extreme pressure antiwear performance under long-term boundary lubrication conditions. It can be used as extreme pressure antiwear agent for space lubricants, but it requires excellent good solubility, low temperature stability and low volatility.

The synthesis method of lead naphthenate has been disclosed, mainly including metathesis method, direct reaction method, microwave in-situ synthesis method, etc. The preparation of lead naphthenate by metathesis method is to saponify naphthenic acid with sodium hydroxide solution, add lead acetate solution to carry out metathesis reaction, add solvent oil and then process to obtain lead naphthenate. The "Research on Direct Synthesis of Lead Naphthenate" published in the fourth issue of "Fine Chemical Industry" in 1991 disclosed that under the catalysis of carboxylic acid and its derivatives, naphthenic acid and lead oxide were directly reacted, and 200# solvent gasoline was used as the dilution. Preparation of lead naphthenate additives. In August 2011, "Microwave in-situ synthesis of lead naphthenate and lead alkyl salicylate and their tribological properties" published in "Acta Chemical Physics" disclosed the synthesis of lead naphthenate liquid paraffin solution by microwave in-situ synthesis. .

However, due to the lack of selection of naphthenic acid raw materials, lead naphthenate currently used in conventional lubricating greases has poor solubility in polyalkylcyclopentane, is easy to separate out at low temperature, and is not refined in naphthenic acid. Oil and solvent gasoline are diluents, which are volatile and cannot meet the requirements of space lubricants.

It should be noted that the information disclosed in the preceding Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.

SUMMARY OF THE INVENTION

A main purpose of the present invention is to overcome at least one of the above-mentioned defects of the prior art, to provide an extreme pressure anti-wear agent composition, an extreme pressure anti-wear agent comprising the extreme pressure anti-wear agent composition, and application of the extreme pressure anti-wear agent composition The space lubricant of the antiwear agent is used to solve the problems of poor solubility and low stability of the existing extreme pressure antiwear agent in the space lubricant based on polyalkylcyclopentane, and it is difficult to meet the low volatility requirements of the space lubricant .

In order to achieve the above object, the present invention adopts the following technical solutions:

A first aspect of the present invention provides an extreme pressure antiwear agent composition comprising naphthenate and a diluent, wherein the diluent is polyalkylcyclopentane, and the general formula of polyalkylcyclopentane is as follows: I show:

wherein, R ¹ is a normal or isomeric alkyl group of C ₅ -C ₂₄ , and n is a positive integer of 2-4;

The naphthenic acid salt is prepared by reacting naphthenic acid with a metal salt, and the average relative molecular mass of the naphthenic acid is 170-300.

According to one embodiment of the present invention, the ratio of naphthenate to diluent is 100:(10-100).

According to an embodiment of the present invention, the naphthenic acid is a segmented naphthenic acid with a distillation temperature of 130° C. to 145° C. after vacuum distillation under a vacuum degree of 1 torr to 3 torr.

According to one embodiment of the present invention, the naphthenic acid is a neutral oil-removed refined naphthenic acid.

According to one embodiment of the present invention, the naphthenic acid is a fractionated naphthenic acid with a distillation temperature of 130°C to 145°C.

According to one embodiment of the present invention, R ¹ is a C ₁₀ -C ₂₄ n- or iso-alkyl group, and n is 2-3.

According to one embodiment of the present invention, the naphthenate is lead naphthenate.

According to an embodiment of the present invention, the metal content in the extreme pressure antiwear agent composition is 20wt% to 40wt%.

A second aspect of the present invention provides an extreme pressure antiwear agent comprising the above extreme pressure antiwear agent composition.

A third aspect of the present invention provides a space lubricant, comprising a base oil and the above extreme pressure antiwear agent, wherein the base oil is the polyalkylcyclopentane.

According to an embodiment of the present invention, the mass ratio of the base oil to the extreme pressure antiwear agent is 100:(1-15).

As can be seen from the above technical solutions, the beneficial effects of the present invention are:

The extreme pressure anti-wear agent composition proposed by the present invention, by selecting naphthenic acid with a specific molecular weight range as a raw material, and subjecting it to refining treatment, so that the obtained naphthenate salt has good properties in the polyalkylcyclopentane diluent. Solubility, excellent low temperature stability and low volatility; in addition, by using polyalkylcyclopentane as a diluent to replace the original mineral oil or solvent gasoline, etc., the volatilization of extreme pressure antiwear agents can be further reduced sex. The prepared extreme pressure antiwear agent is suitable for space lubricants and has good industrial application prospects.

Detailed ways

The following contents provide different embodiments or examples, so that those skilled in the art can implement according to the description text. Of course, these are merely examples and are not intended to limit the invention. The endpoints of ranges and any values disclosed herein are not limited to the precise ranges or values, which are to be understood to encompass values proximate to those ranges or values. For ranges of values, the endpoints of each range, the endpoints of each range and the individual point values, and the individual point values can be combined with each other to yield one or more new ranges of values that Ranges should be considered as specifically disclosed herein.

A first aspect of the present invention provides an extreme pressure antiwear agent composition comprising naphthenate and a diluent, wherein the diluent is polyalkylcyclopentane, and the general formula of polyalkylcyclopentane is as follows: I show:

wherein, R ¹ is a normal or isomeric alkyl group of C ₅ -C ₂₄ , and n is a positive integer of 2-4;

The naphthenic acid salt is prepared by reacting naphthenic acid with a metal salt, and the average relative molecular mass of the naphthenic acid is 170-300. Wherein, the "average relative molecular mass" is measured by SH/T 0583 method.

Those skilled in the art know that naphthenic acid, also known as petroleum acid, is a complex mixture of carboxylic acids separated during crude oil processing, including cyclopentyl, cyclohexyl carboxylic acid, etc. The molecular weight is generally 120 to 700, and its main part is Cycloalkyl organic carboxylic acids of 9 to 20 carbon atoms. The inventors of the present invention have found that the naphthenate salt obtained by cutting a specific fraction of naphthenic acid under reduced pressure distillation and refining the naphthenic acid with a specific molecular weight range is used as an extreme pressure antiwear agent. It has excellent solubility and low temperature stability in cyclopentane. Specifically, the average relative molecular mass of the selected naphthenic acid in the present invention is 170-300, preferably 180-280, for example, 180, 220, 250, 280 and the like. Wherein, the naphthenic acid contains at least one five-membered ring or six-membered ring, on which is connected a straight-chain or branched-chain alkyl group, and contains a carboxyl group. Optionally, for example, the naphthenic acid includes, but is not limited to, a mixture of monocyclic and polycyclic organic carboxylic acids containing five-membered and/or six-membered rings, the simpler structures are methylcyclopentane, methyl ring Caproic acid etc.

In some embodiments, the above-mentioned naphthenic acid of the specific distillation section is the naphthenic acid of the distillation section with a distillation temperature of 130 ° C to 145 ° C under vacuum degree of 1 torr to 3 torr, such as 130 ° C, 132 ° C, and 132 ° C after vacuum distillation. °C, 135 °C, 141 °C, 145 °C, etc.

In addition, according to the present invention, polyalkylcyclopentane has extremely low volatility and saturated vapor pressure, good viscosity-temperature properties and lubricating properties, and is an ideal space lubricant base oil. Naphthenates, especially lead naphthenates, have low volatility, but they still need to have excellent solubility, low temperature stability and low volatility as extreme pressure antiwear agents. The inventors of the present invention have found that by using polyalkylcyclopentane as a diluent to replace the original mineral oil or solvent gasoline, etc., the volatility of extreme pressure antiwear agent can be reduced, and it can be further combined with polyalkylcyclopentane. Alkane as a base oil space lubricant has good compatibility.

In some embodiments, it also includes refining the aforementioned naphthenic acid to remove neutral oil to obtain refined naphthenic acid. Neutral oil is often mixed with naphthenic acid, and the neutral oil has an adverse effect on the low volatility of the extreme pressure antiwear agent, and must be removed before it can be used to synthesize naphthenate. To remove the neutral oil from the naphthenic acid, the naphthenic acid can be neutralized to alkaline with an alkaline solution, the neutral oil is repeatedly extracted with petroleum ether, and then the lye is acidified with a strong acid, washed, dried, filtered and distilled. After a series of operations, the purified naphthenic acid from which neutral oil has been removed is obtained. By refining the naphthenic acid, the volatility of the antiwear agent composition can be greatly reduced, and at the same time, subsequent unnecessary side reactions can be avoided, which is beneficial to improve the performance of the obtained extreme pressure antiwear agent composition.

In some embodiments, the ratio of naphthenate to diluent is 100:(10-100), eg, 100:20, 100:35, 100:50, 100:55, 100:60, and the like. If the concentration of naphthenate is too high, the viscosity will be very large, which is inconvenient to use, and may also cause precipitation, which is not suitable for stable storage. Preferably, the aforementioned ratio is 100:(20-60). The aforementioned metal salt can generally be acetate or the like, and the naphthenate is preferably lead naphthenate. In some embodiments, the metal content in the extreme pressure antiwear agent composition is 20wt%-40wt%, preferably 25wt%-35wt%, such as 25wt%, 28wt%, 30wt%, 32wt%, etc. Taking lead acetate as an example, the preparation process of the specific extreme pressure antiwear agent composition is mainly as follows:

The above-mentioned purified naphthenic acid with a specific molecular weight is completely saponified by using sodium hydroxide solution with a mass fraction of 10% to 20%. The reaction temperature is 80 ° C ~ 100 ° C, the reaction time is 1 h ~ 3 h, and organic solvents such as toluene are added to make it fully dissolved. . Under the conditions of stirring and refluxing the organic solvent, lead acetate solution with a mass fraction of 15% to 20% is added to react to generate lead naphthenate. The reaction time is 1h to 3h, and the lead acetate is slightly excessive. After the reaction, the system was allowed to stand, the aqueous layer was discarded, and the organic layer was washed 3-6 times with hot water. After dehydration, the aforementioned polyalkylcyclopentane is added as a diluent, and the extreme pressure antiwear agent composition of the present invention is obtained by distillation under reduced pressure, which is a brown viscous liquid.

The present invention also provides an extreme pressure antiwear agent, comprising the aforementioned extreme pressure antiwear agent composition. According to actual needs, other auxiliary agents may also be added thereto, and the present invention is not limited thereto.

According to the present invention, polyalkylcyclopentanes have very low volatility. The naphthenate after the aforementioned treatment can have good compatibility with the diluent polyalkylcyclopentane. Optionally, the aforementioned R ¹ is a normal or isomeric alkyl group of C ₁₀ to C ₂₄ , and n is 2 to 3, that is, the polyalkylcyclopentane contains 2 or 3 normal or isomeric C ₁₀ ~ _C24 alkyl chain polyalkylcyclopentane. It should be noted that, the preparation method of the polyalkylcyclopentane of the present invention can be prepared by conventional methods in the art or commercially available, and the present invention is not limited thereto.

The present invention also provides a space lubricant, comprising the above-mentioned extreme pressure antiwear agent and a base oil, wherein the base oil is polyalkylcyclopentane. In some embodiments, the mass ratio of the base oil to the extreme pressure antiwear agent is 100:(1-15), preferably 100:(3-10). By selecting the raw material of naphthenic acid with specific molecular weight and refining it, the obtained naphthenate can use low-volatility polyalkylcyclopentane as a diluent, so that the obtained extreme pressure antiwear agent can be used in space lubricants. The base oil polyalkylcyclopentane has excellent solubility and low temperature stability, and has good low volatility characteristics, meeting the low volatility requirements of space lubricants.

The present invention will be further illustrated by the following examples, but the present invention is not limited thereby.

Preparation Example 1

This preparation example is used to illustrate the preparation method of polyalkylcyclopentane used in the following examples.

After mixing n-decanol, solid potassium hydroxide and dicyclopentadiene, add it into a flask equipped with a stirrer, a separatory funnel, a condenser, a water separator, and a thermometer for heating reaction. When the water separator no longer has water to generate, The reaction was stopped, and the reaction product was washed with water, dried and filtered to obtain poly-n-decylcyclopentadiene. Poly-n-decylcyclopentadiene and n-heptane are made into a solution with a dilution of 10%, 200g of this solution is added with 3.6g of amorphous nickel catalyst and mixed, put into an autoclave, and the hydrogen is fed until the hydrogen pressure reaches 5MPa, The mixture was heated to 155°C under good stirring, and reacted for 20 h. The reaction product was cooled and filtered to obtain poly-n-decylcyclopentane.

Example 1

Taking naphthenic acid with an average relative molecular mass of 203 (decompression distillation of naphthenic acid, vacuum degree of 3 torr, to obtain a distillation segment with a distillation temperature of 130 ° C ~ 135 ° C) as a raw material, the neutral oil therein is removed. Then add 10% sodium hydroxide solution for complete saponification, saponification temperature is 85 ℃, saponification time is 1h, then toluene is added to make it fully dissolved, and 15% lead acetate solution is added under the conditions of stirring and toluene reflux to react for 2h Generate lead naphthenate. After the reaction, the water layer was discarded, and the organic layer was washed with hot water at 80° C. 4 times. After dehydration, the polyalkylcyclopentane of Preparation Example 1 was added as a diluent, and the mass ratio of the diluent to lead naphthenate was 20:100. The extreme pressure antiwear agent is obtained by distillation under reduced pressure.

Example 2

Taking naphthenic acid with an average relative molecular mass of 203 (decompression distillation of naphthenic acid, vacuum degree of 3 torr, to obtain a distillation segment with a distillation temperature of 130 ° C ~ 135 ° C) as a raw material, the neutral oil therein is removed. Then add 20% sodium hydroxide solution for complete saponification, the saponification temperature is 90℃, the saponification time is 1.5h, then toluene is added to make it fully dissolved, and 15% lead acetate solution is added under the conditions of stirring and toluene reflux to react 3h generate lead naphthenate. After the reaction, the water layer was discarded, and the organic layer was washed with hot water at 80°C for 6 times. After dehydration, the polyalkylcyclopentane of Preparation Example 1 was added as a diluent, and the mass ratio of the diluent to lead naphthenate was 50:100. The extreme pressure antiwear agent is obtained by distillation under reduced pressure.

Example 3

Taking naphthenic acid with an average relative molecular mass of 262 (decompression distillation of naphthenic acid, vacuum degree of 3 torr, obtaining distillation temperature of 135 ℃～145 ℃ distillation section) as raw material, it is purified by freezing filtration method, Remove fatty acids and neutral oils from it. Then add 20% sodium hydroxide solution for complete saponification, the saponification temperature is 90℃, the saponification time is 1.5h, then toluene is added to make it fully dissolved, and 15% lead acetate solution is added under the conditions of stirring and toluene reflux to react 3h generate lead naphthenate. After the reaction, the water layer was discarded, and the organic layer was washed with hot water at 80°C for 6 times. After dehydration, the polyalkylcyclopentane of Preparation Example 1 was added as a diluent, and the mass ratio of the diluent to lead naphthenate was 50:100. The extreme pressure antiwear agent is obtained by distillation under reduced pressure.

Comparative Example 1

The method of Example 3 was used to prepare the extreme pressure antiwear agent. The difference was that with naphthenic acid with an average relative molecular mass of 346 (p-naphthenic acid was distilled under reduced pressure, and the vacuum degree was 3 torr, the distillation temperature was 150° C. to 155° C.) °C fractionation) as the raw material.

Comparative Example 2

The method of Example 3 was used to prepare the extreme pressure antiwear agent, except that the diluent was 150SN neutral oil, and the proportion of the diluent was unchanged.

Test Example 1

The extreme pressure antiwear agents of Examples 1 to 3 and Comparative Examples 1 and 2 were tested, and the test methods and results are shown in Table 1.

Table 1

As can be seen from Table 1 above, the extreme pressure antiwear agent of the present invention exhibits excellent performance in polyalkylcyclopentane base oil, compared with the raw material of naphthenic acid of non-specific molecular weight or the use of neutral oil as Diluent extreme pressure antiwear agents, all of which have better solubility, low temperature stability and low volatility, suitable for space lubricants.

It should be noted by those skilled in the art that the described embodiments of the present invention are merely exemplary, and various other substitutions, changes and improvements may be made within the scope of the present invention. Therefore, the present invention is not limited to the above-described embodiments, but only by the claims.

Claims (9)

1. The extreme pressure antiwear agent composition comprises naphthenate and a diluent, wherein the diluent is polyalkylcyclopentane with a general formula shown in a formula I:

wherein R is¹Is C₅～C₂₄N is a positive integer of 2-4;

the naphthenate is prepared by reacting naphthenic acid with metal salt, and the average relative molecular mass of the naphthenic acid is 170-300;

the naphthenic acid is refined naphthenic acid without neutral oil.

2. The extreme pressure antiwear agent composition of claim 1, wherein a mass ratio of the naphthenate to the diluent is 100: (10-100).

3. The extreme pressure antiwear agent composition according to claim 1, wherein the naphthenic acid is a naphthenic acid which is distilled under a vacuum degree of 1torr to 3torr and has a distillation temperature of 130 ℃ to 145 ℃.

4. The extreme pressure antiwear agent composition of claim 1, wherein R is¹Is C₁₀～C₂₄N is 2-3.

5. The extreme pressure antiwear agent composition of claim 1, wherein the naphthenate is lead naphthenate.

6. The extreme pressure anti-wear additive composition of claim 1, wherein the metal content in the extreme pressure anti-wear additive composition is 20-40 wt%.

7. An extreme pressure anti-wear additive, comprising the extreme pressure anti-wear additive composition as defined in any one of claims 1to 6.

8. A space lubricant comprising a base oil and the extreme pressure antiwear agent of claim 7, wherein the base oil is a polyalkyl cyclopentane.

9. The space lubricant as recited in claim 8, characterized in that the mass ratio of the base oil to the extreme pressure antiwear agent is 100: (1-15).