DE2107577A1 - New lubricant composition - Google Patents

Description

The invention relates to the use of thio-organometallic Complexes as additives for the production of lubricant compositions, hydraulic fluids, transformer oils, Greases and elastomers.

The invention relates in particular to lubricant compositions which contain at least one lubricating oil and at least one of the aforesaid contain thio-metal! organic complexes.

These lubricant compositions have a surprisingly better stability to oxidation.

It is known that to improve the oxidation stability of certain lubricants, in particular lubricating oils for engines, suggested the addition of antioxidant additives, which mostly consist of zinc dithiophosphates and in certain cases of dithiocarbamates, phenols or amines.

These connections usually have one or more of the following disadvantages:

They have limited antioxidant effects, especially in the presence of certain metals such as iron and copper. - You are sensitive to increases in temperature.

109838/1530

- They cause precipitates to form.

- They cause certain engine parts to corrode (such as the S over-stock).

It has now surprisingly been found that certain organic thiometallic Complexes have the advantage of having an increased antioxidant effect, even at high temperatures and in the presence of strong metal contents. These compounds are both in the case of oils based on petroleum as a starting point, as well effective against oils with a synthetic base. They also give the lubricating oils to which they are added good "anti-wear" properties. and "extreme pressure" properties.

The lubricant compositions according to the invention are characterized in that they contain at least one thioorganic complex of the following formula:

These thio-metal-organic complexes form around one Element M, which is tin, antimony. Lead, bismuth, zinc, cadmium or a transition metal such as chromium, manganese, iron, cobalt, nickel or copper, the element M in the η oxidation state being surrounded by η identical or different ligands.

In the above formula, the substituents have the following meanings:

R ^ and R "each mean a monovalent radical, namely an aliphatic, alicyclic or aromatic hydrocarbon radical, which can also be halogenated or nitrated, or 1-3 Heteroatoms such as oxygen, sulfur and nitrogen can contain, in general, these radicals contain 1-20 carbon atoms.

109038/1530

Y denotes hydrogen or a radical R ¹ , R'-O, R ¹ -S or R ¹ -CO, where R ^{1 is} a monovalent hydrocarbon radical with 1-20 carbon atoms.

Y and R-, or R ^ can also together form a divalent hydrocarbon Form a substance residue with 1-20 carbon atoms and 0-3 oxygen, sulfur or nitrogen atoms.

Each atom Z can be an oxygen or sulfur atom, among the prerequisite that at least one atom Z represents a sulfur atom in at least one of the η ligands.

Each ligand can be represented by two mesomeric formulas with a negative charge:

C »Z> X - Z

YC * - ^C

This is represented by a single formula of the following kind:

Y -

As examples of radicals as defined by R and R "are cited the following monovalent radicals: ^ä

Methyl, ethyl, propyl, isopropyl »butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, nonyl, Decyl, undecyl, dodecyl, heptadecyl, methoxy, xthoxy, propoxy, Butoxy, cyclopentyl, cyclohexyl, cycloheptyl, phenyl, benzyl, Phenethyl, cumyl, p-iodophenyl, p-nitrobenzyl, methoxyphenyl, vinyl

109838/1530

propenyl, butenyl-2, pentenyl-3, ethynyl, propynyl, furyl-2, Thienyl-2 and trifluoromethyl.

The following monovalent radicals are cited as radicals Y:

Methyl, ethyl, isopropyl, sec-butyl, octyi, decyl, dodecyl, Phenyl, benzyl, methoxy, ethoxy, propoxy, methylthio, ethylthio, Acetyl, propionyl, phenethyl, cyclopentyl, cyclohexyl and cycloheptyl.

To illustrate the general formula of the invention The following list, which is not exhaustive, is given for useful compounds:

CH,

- CH ₂ - CH ₂ - C ^

^C 6 ^H 5

CH ₃ / CH ₃

". c7 kn CH-CIU- C ^ l CS

CH,

CH ₃ -CH ₂ -O - C

C-S

C-O

109838 / 153Ö

The preparation of the organic thioorganic compounds which can be used according to the invention Complexes can be made by various known methods.

The corresponding β-diketones are preferably used as a starting point. In certain cases one does not have the desired © ß-diketone; then it is possible to synthesize it in a suitable way, e.g. by condensation of an ester with a monoketone. The fixation of a radical Y, which is not hydrogen, can be carried out on ß-Diketone can be carried out itself, or after the thioorganic complex has been formed from it or from one of its sulfur derivatives Has. It is also possible to react a sodium salt of β-diketone with an alkyl halide if Y is an alkyl group wants to use.

For the synthesis of the thioorganic complexes which can be used according to the invention, the available or synthesized ß-diketone must be sulphurized will. This sulfurization can be carried out in any known manner. The sulpharizing agent used is e.g. hydrogen sulphide, if desired in an acidic medium or in a solvent. This sulfurization can be carried out in the presence of a desired metal salt. In this case, receives in general, the desired thioorganic complex or a mixture of complexes of the above formula. Will If the sulfurization is carried out in the absence of a metal salt, a monothioketone or a dithioketone is obtained in some cases or mixtures thereof or a mixture of one of these with the starting β-diketone. It is generally sufficient to have a desired Metal salt with these ketones or their mixture added "to a thioorganic complex or a mixture of the thioorganisdhe" Obtain complexes according to the above formula.

The use according to the invention of this substance relates to all oils as a base, in particular those obtained by solvent extraction a petroleum fraction or another refining process or obtained by synthesis.

The thioorganic complexes are added to the base oils in small amounts, for example, ö _f 05-5 wt .-%, preferably 0.2-2 wt .-%.

10983B / 1530

The remarkable antioxidant properties which the lubricating oils imparted by the addition of the thioorganic complexes are likely based on their ability to destroy the hydroperoxides as well as their reactivity to them free radicals.

The "anti-wear" and "extreme pressure" properties are related to the tendency of these complexes to settle on metallic ones To fix surfaces, which leads to a protection of the latter.

The invention is to be explained in more detail in the following examples, without being restricted thereto.

109838/1530

Examples 1-5

The base oils are mixed with the thio-organometallic complexes indicated in Table I in the indicated amount. the The resulting mixtures are subjected to a particularly strict oxidation test: the sample is kept at 160 ° C and in a pure Oxygen atmosphere in the presence of iron naphthenate (6 ppm) and lead oxide (6 g / liter) stirred vigorously so that the specified Amount of oxygen is absorbed after 7 hours of testing. The smaller this amount, the better the resistance of the mixture against oxidation.

For comparison purposes, these reaction conditions were also used a pure solvent-type base oil, and a solvent-type base oil which is a classic antioxidant Contains additive, as well as a pure synthetic ester-type oil. The test results are summarized in the following table I:

109838/1530

Tabel

oil

Additive amount (wt .-%)

absorbed sour

fMoI / liter)

200 neutral sol

vens (Zarzaitin)

200 neutral solvent (zarzaitin)

500 neutral sol

vens' (Zarzaitin)

Zinc dialkyldithiophosphate (S / 7 wt% Zinc) 0.25

CH, 0.30

C- S

i C ₃ H ₇ -C '{

Co

c "- * s

CH

CIL

C-S

C-S

CIL

0.15

2-ethyl hexyl sebacate

0.20

0.20

- S.

- S.

0.20

3 ,

10983Ö / 153Ö 14.2

8.32

6.54

0.11

0.16

0.09

12.4 0.28

Examples. 6-8

The base oils are mixed with the thioorganic complexes given in Table II in the amounts given.

The mixtures obtained are tested according to the method of "Federal Test Method Standard" 791a No. 6503 of 12/30/61 examined; this
corresponds to the French standard AIR 1650 A from January 20th, 1961. A “Precision Shell Pour Ball EP Tester” machine is used at 1500 revolutions per minute.

For comparison purposes, a pure base oil and a base oil with a classic "extreme pressure" additive are subjected to the same tests. The results (expressed as the load before the '
Welding) are shown in the following table II:

T a b e lie Ii

Bei-I - K ₁ game ^υχ

Additive

Amount of load

% By weight) 'before welding

150 neutral

¹ solvent (zarzaitin)

Zinc dialkyl thiophosphate (8.7% by weight zinc)

CIL

C ₉ H-CI 2 5 v >>

0.1

0.1

C-S

C-O

0.1 0.1

(kg) 112-

126

126

141

126

109338/1530

Examples 9-12

A base oil is mixed with the thio-organometallic complexes mentioned in Table III in the amounts indicated. the
The resulting mixtures are subjected to a particularly strict oxidation process: the sample is kept at 160 ° C. and under a pure oxygen atmosphere in the presence of iron naphthenate
(6, ppm) and lead oxide (6 g / liter) stirred vigorously so that the specified amount of oxygen is absorbed after 7 hours of testing. The smaller this amount, the better the resistance of the mixture to oxidation.

Table III

% p-iel- oil

Additive

Amount C weight%)

more absorbed

oxygen

(Mol / liter)

200 neutral

Solvens (Zarzaitin

200 neutral solvents

(Zarzaitin)

200 neutral

Solvent (zarzaitin)

CH ₃

IZn

200 neutral

Solvent τ (Zarzaitin

Ni

0.15

0.12

0.25

0.04

0.5

0.19

0.20

0.03

09838/153

Claims (4)

- li - claims 1. Lubricant composition based on a hydrocarbon lubricating oil, characterized in that it contains at least one thio-organometallic complex of the following general Formula contains: in which mean: | M an element from the group of transition metals or zinc, cadmium, tin, lead, antimony or bismuth, η the degree of oxidation of the element M, R ₁ and R "a monovalent hydrocarbon radical of 1-20 carbon atoms and 0-3 heteroatoms, namely halogen, oxygen, sulfur or nitrogen, Y is hydrogen or the radicals R ¹ , R ¹ 0, R ¹ S or R ¹ CO, where R ¹ denotes a hydrocarbon radical with 1-20 carbon atoms, where Y and R .. or R together also have a divalent carbon radical 1-20 carbon atoms and 0-3 heteroatoms, namely oxygen, sulfur or nitrogen, may form, Z represents an oxygen or sulfur atom, wherein at least ieiner must be a sulfur atom i of 2 η Z atoms. 2. Lubricant composition according to claim 1, characterized in that that a base oil from petroleum or a synthetic lubricant is used as the lubricating oil. 3. Lubricant composition according to claim 1, characterized in that that it contains at least one of said thio-organometallic complexes in an amount of 0.05 ^ 5 wt .-%. 4. lubricant composition according to claim 1, characterized in that that it contains at least one of the said thio-organometallic complexes in an amount of 0.2-2% by weight. 109838/1530%