CN102887918A - Preparation and application of dialkyl dithiophosphate hydroxyl derivative and boric acid ester thereof - Google Patents

Abstract

The invention relates to a preparation method of a hydroxyl derivative containing dialkyl dithiophosphate and boric acid ester (II) thereof, wherein the hydroxyl derivative and the boric acid ester (II) can be used as environment-friendly lubricating oil additives, can effectively improve the antifriction performance of environment-friendly base oil and have a certain anti-wear effect. The preparation method comprises the following steps: under certain reaction conditions, alcohol reacts with phosphorus pentasulfide to generate dialkyl dithiophosphate, and then the dialkyl dithiophosphate reacts with propylene oxide to prepare a hydroxyl derivative containing dialkyl dithiophosphate groups; and the latter can be used for generating borate with borate according to proper stoichiometric proportion. The method has simple process and mild conditions, and is suitable for industrial production.

Description

Preparation and Application of Hydroxyl Derivatives of Dialkyl Dithiophosphoric Acid and Its Borate Ester

Technical field:

The present invention relates to the preparation of hydroxyl derivatives containing dialkyl dithiophosphoric acids and their borate esters, and their use as environmentally friendly lubricating oil load additives. It belongs to the field of lubricating oil.

technical background:

In order to meet the requirements of actual working conditions, various additives must be added to lubricating oil. For environmentally friendly lubricants, the performance of additives in base oils and their impact on the ecological environment must be considered. Since the base oil of biodegradable lubricants is very different from traditional mineral oil in terms of chemical structure and interfacial properties, and the biodegradability of the additive itself must be considered, most of the traditionally used lubricating oil additives cannot Directly used in biodegradable lubricants.

According to the requirements of the German "Blue Angel" standard for environmentally friendly lubricating oil additives, the boron-containing compounds that can be used as environmentally friendly lubricating oil additives are mainly ashless borates, which can be regarded as boric acid B(OH) Derivatives in which the hydrogen in ₃ is replaced by an organic group. Because of its non-toxic and odorless, good environmental adaptability, high thermal stability and certain anti-wear and anti-friction properties, borates have attracted more and more people as environmentally friendly lubricant additives and potential ZDDP substitute properties. focus on. The research on organic borates containing only C, H, and O in the molecule as lubricating oil additives started earlier (see U.S. Patents US5759965, US5482591, US4584115 and US5062975, etc.), but this type of borate does not contain other substances except B. Active elements, so their functions are relatively single, and it is difficult to meet the needs of increasingly complex working conditions, which limits their application to a certain extent.

Since the end of the last century, in order to seek higher-performance, multi-effect boron-containing lubricating oil additives, researchers began to introduce active elements such as S, P, and N into borate molecules, which to a certain extent improved borate Anti-friction and anti-wear properties of lubricating oil additives. In recent years, a variety of borate additives with different molecular structures and different tribological properties have been reported one after another. For example, in US004474670, a mixed borate produced by using hindered phenol, hydroxylamine and boronating agent was reported, and passed Its tribological properties were investigated by low-velocity friction tester (LVFA), and it was found that it was an effective friction reducer; thermal oxidation stability experiments showed that it was also an excellent antioxidant. Patents US6001779, US5169547, and USRE032295 also report similar structures.

Additives containing sulfur and phosphorus elements can also be used as environmentally friendly lubricant additives because they can provide nutrients that are beneficial to the growth of microorganisms and can improve the biodegradability of lubricants.

Invention content:

The object of the present invention is to provide two kinds of load additives containing S, P (see formula I) and S, P, B (see formula II) active elements which can be used for environment-friendly lubricating oil.

Another object of the present invention is to provide a preparation method of the above two loading additives, which is suitable for industrial production.

The two compounds containing S, P (see formula I) and S, P, B (see formula II) active elements provided by the present invention have the following structures respectively:

In the two formulas, R ₁ and R ₂ are the same or different, straight-chain or branched alkanes with 4-16 carbon atoms; R ₁ and R ₂ can also be the same or different, with different benzene rings An aromatic ring group branched with fewer than four carbon atoms.

The present invention provides a preparation method of the above two compounds, which is characterized in that the method comprises the following three steps in sequence (step 2 can obtain compound I).

step 1:

Add alcohols or phenols with structural formulas R ₁ OH and R ₂ OH (R ₁ and R ₂ are the same or different straight chains with 4-16 carbon atoms) in a reaction kettle equipped with strong stirring and condensing reflux. or branched alkanes; R ₁ and R ₂ can also be the same or different, with no less than four carbon atom branched aromatic ring groups on the benzene ring), in the presence of solvent toluene or no solvent ( Preferably no solvent is used), and P ₂ S ₅ is added in batches at room temperature to 80°C (preferably room temperature). The molar ratio of alcohol or phenol to P ₂ S ₅ is 4-4.2, and the amount of each input is about 1/4-1/6 of the total weight of P ₂ S ₅ . After feeding, raise the temperature to 90-120°C, stir vigorously for 2-10 hours, filter out excess P ₂ S ₅ , and the first step reaction is completed to obtain intermediate A.

Step 2:

Add intermediate A to the reaction kettle, in the presence of solvent toluene or no solvent (preferably no solvent), add propylene oxide dropwise at room temperature to 50°C (preferably room temperature), the molar ratio of propylene oxide to intermediate A The temperature is 1-1.5, and the temperature is raised to 50-70° C. after dropping, and the second-step reaction is completed after 2-8 hours of reaction, and the hydroxyl derivative (I) of dialkyl dithiophosphoric acid is obtained.

Step 3:

Add boric acid and an appropriate amount of water-carrying agent (water-carrying agent can be benzene, toluene, xylene, n-heptane, etc.) Under reflux state, drop the hydroxyl derivative (I) of dialkyl dithiophosphoric acid, the molar ratio of the hydroxyl derivative (I) of dialkyl dithiophosphoric acid to boric acid is 3～3.1; After the theoretical amount, the reaction is stopped, filtered, and the solvent is evaporated to obtain the boric acid ester (II) of the hydroxyl derivative of dialkyl dithiophosphoric acid.

The two compounds (I) and (II) provided by the present invention can be used alone or together, and added to environment-friendly base oils (diester, PAO or rapeseed oil, etc.) as load additives, which have good oil solubility and hydrolysis stability Non-toxic and less corrosive, and high thermal stability, and has a certain oxidation resistance.

Description of drawings

Fig. 1 is the infrared analysis result of the borate (b) of di-n-butyl dithiophosphoric acid hydroxyl derivative.

Detailed ways

Below by example the present invention will be further described.

Example 1

Add an appropriate amount of C ₄ H ₉ OH into the three-necked flask, add P ₂ S ₅ in batches under strong stirring (the molar ratio of the two is 4:1), continue stirring at room temperature for 0.5 h, then raise the temperature to 90°C and continue the reaction for 3 h , after the reaction solution is thoroughly clarified, the intermediate is obtained; take an appropriate amount of the above intermediate product in a three-necked flask, add an equimolar amount of propylene oxide dropwise at room temperature, keep the temperature for 0.5h, then gradually raise the temperature to 50°C, and continue the reaction for 2h. Obtain di-n-butyl dithiophosphoric acid hydroxyl derivative (a);

Add boric acid and the above product in a molar ratio of 1:3 into a reaction bottle equipped with a water separator, and add an appropriate amount of acidic resin as a catalyst and an appropriate amount of benzene as a water-carrying agent, and react at 70-80°C for 4-6 hours. After the water close to the theoretical amount is separated, the reaction is completed, and the benzene is distilled off after filtration to obtain a colorless viscous liquid, namely the borate (b) of di-n-butyl dithiophosphoric acid hydroxyl derivative.

Elemental analysis results (theoretical value/measured value) of borate (b) of di-n-butyl dithiophosphoric acid hydroxyl derivative: C element (41.75%/42.29%); H element (7.64%/7.92%); S element (21.36%/21.18%); P element (11.50%/11.23%); B element (1.14%/1.19%). Its infrared spectrum analysis result is shown in accompanying drawing 1.

Example 2

Add an appropriate amount of dodecylphenol into a three-neck flask, add an appropriate amount of toluene as a solvent _, add _P2S5 in batches under vigorous stirring (the molar ratio of the two is 4:1), continue stirring at room temperature for 0.5h, and then raise the temperature to Continue to react at 110°C for 5 hours. After the reaction solution is completely clarified, evaporate the toluene to obtain the intermediate; take an appropriate amount of the above intermediate product in a three-necked flask, add an equimolar amount of propylene oxide dropwise at room temperature, and keep the reaction for 0.5 hours, and then Gradually raise the temperature to 50°C and continue the reaction for 3 hours to obtain the hydroxy derivative of docosylphenol dithiophosphoric acid;

Add boric acid and the above product into a reaction bottle equipped with a water separator at a molar ratio of 1:3, and add an appropriate amount of acidic resin as a catalyst and an appropriate amount of toluene as a water-carrying agent, and react at 110°C for 5 to 8 hours. After the water close to the theoretical amount is produced, the reaction is completed, and the toluene is distilled off after filtration to obtain a colorless viscous liquid, that is, a boric acid ester of a behenylphenol dithiophosphoric acid hydroxyl derivative.

Example 3

This example is a tribological performance test.

Get example 1 and make di-n-butyl dithiophosphoric acid hydroxy derivative and the borate ester of di-n-butyl dithiophosphoric acid hydroxy derivative, take Mobil diester A51 as base oil on four-ball friction and wear testing machine to evaluate all The anti-wear and anti-friction performance of synthetic additives, the test conditions are: according to the GB/T 3142-82 standard method, the maximum non-seizing load P _B and sintering load P _D of the sample are measured to evaluate the extreme pressure performance; under the load of 392N, according to The SH/T 0189-92 standard method measures the wear spot diameter (WSD) of the sample to evaluate the anti-wear performance; under the load of 392N, the friction coefficient of the sample under different loads is measured according to the ASTM D5183-95 (1999) standard method ( μ) to evaluate the anti-friction performance. The test results are listed in Table 1 and Table 2.

As can be seen from Table 1, after adding additive (a) or (b), the P _B value of the diester is significantly improved, even only adding 0.5% concentration, the P _B value of A51 has increased by 60%, and (a ) has a certain effect on improving the _PD value of the diester. It can be seen from Table 1 that after adding additive (a) or (b), the wear scar diameter and friction coefficient of the diester are greatly reduced, which shows that the two compounds provided by the present invention have good anti-friction and anti-wear effects.

Table 1 P _B , P _D values of two compounds with different concentrations as additives in diester

Table 2 The wear spot diameter (WSD) and friction coefficient (μ) of two compounds with different concentrations as additives in diester

Claims (9)

1. general formula (I) is the hydroxy derivatives of dialkyl dithiophosphoric acid, it is characterized in that: R in the formula (I) ₁, R ₂For identical or different, carbon atom number are the alkane of the straight or branched of 4-16; Or R ₁, R ₂For on identical or different, the phenyl ring with the aromatic ring group that is no less than the four carbon atom side chain.

2. general formula (II) is the boric ester derivative of formula (I), it is characterized in that: R in the formula (II) ₁, R ₂For identical or different, carbon atom number are the alkane of the straight or branched of 4-16; R ₁, R ₂Also can be on identical or different, the phenyl ring with the aromatic ring group that is no less than the four carbon atom side chain.

3. by the preparation method with dialkyl dithiophosphoric acid hydroxy derivatives of general formula (I) claimed in claim 1, it is characterized in that: it is R that reactor adds structural formula ₁OH and R ₂The alcohol of OH or phenol, R ₁, R ₂For identical or different, carbon atom number are the alkane of the straight or branched of 4-16, or R ₁, R ₂For on identical or different, the phenyl ring with the aromatic ring group that is no less than the four carbon atom side chain, have solvent toluene or solvent-free in the presence of, under room temperature～80 ℃, drop into P in batches ₂S ₅, alcohol or phenol and P ₂S ₅Mol ratio be 4～4.2, feeding intake is warming up to 90～120 ℃ after complete, behind violent stirring 2～10h, filters out excessive P ₂S ₅Obtain intermediate A, intermediate A have solvent toluene or solvent-free in the presence of, ℃ lower propylene oxide reaction that adds in room temperature～50, the mol ratio of propylene oxide and intermediate A is 1～1.5, be warming up to 50～70 ℃ of temperature of reaction, behind time 2～8h, obtain the hydroxy derivatives (I) of dialkyl dithiophosphoric acid.

4. by the preparation method of the hydroxy derivatives of the dialkyl dithiophosphoric acid with general formula (I) claimed in claim 3, it is characterized in that: add P in batches ₂S ₅, each input amount is about P ₂S ₅1/4～1/6 of gross weight.

5. by the preparation method of the hydroxy derivatives of the dialkyl dithiophosphoric acid with general formula (I) claimed in claim 3, it is characterized in that: do not use solvent in the reaction system.

6. by the preparation method of the hydroxy derivatives of the dialkyl dithiophosphoric acid with general formula (I) claimed in claim 3, it is characterized in that: add P ₂S ₅, the charge temperature during propylene oxide is room temperature.

7. by the preparation method with boric ester derivative of general formula (II) claimed in claim 2, it is characterized in that: add boric acid and band aqua in the reactor, and the acidic resins of adding reaction system total amount 1wt% are as catalyzer, under reflux state, the hydroxy derivatives (I) that adds dialkyl dithiophosphoric acid, the hydroxy derivatives of dialkyl dithiophosphoric acid (I) is 3～3.1 with the mol ratio of boric acid; After extremely a minute water yield reached theoretical amount, stopped reaction filtered, and steaming desolventizes, and namely gets the boric acid ester (II) of the hydroxy derivatives of dialkyl dithiophosphoric acid.

8. by the preparation method with boric ester derivative of general formula (II) claimed in claim 7, it is characterized in that: the band aqua is benzene,toluene,xylene, normal heptane.

9. the compound of the compound of general formula (I) and general formula (II) is added in dibasic acid esters or synthetic oil or the Rapeseed separately or together and is used as load carrying additive.

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