DE1644861A1 - Synthetic lubricant mixtures - Google Patents

Description

The invention relates to synthetic lubricant mixtures, their wear and corrosion resistance is improved by adding small amounts of certain additives are.

The use of certain acidic phosphorus compounds to increase the load capacity and wear resistance as Additives for synthetic lubricating oils have been suggested previously. However, this has had a number of disadvantages tied together. For example, the lubricating oils have a tendency to be corrosive if they were previously preferred Concentrations and at the extremely high temperatures that lubricants for modern plug-in engines can withstand must be used. It has been shown that some of you do not get along with metal passive fans, which are added to the lubricant in view of its corrosiveness to metals and in particular Improve copper.

It has now been found that by using a combination of certain amounts of certain Dlalkylhydrogenphosphate and metal passivators is possible, synthetic

009838/1718

Produce lubricant mixtures that have very good wear resistance and have corrosion resistance properties at very high temperatures «By adding suitable antioxidants In certain cases, these mixtures can be combined with products with the more modern ones for the lubrication of the engines Cut out the required properties from overshadow jets.

According to the invention there is an ester-based lubricant mixture from one or more liquid neutral polyesters, which have been prepared by reaction under esterification conditions and in one or more stages from

(I) a mono- or polyhydric alcohol with 5 to 15 * preferably 5 to 10 carbon atoms per molecule, with no hydrogen atom attached to a carbon atom in the 2-position is bound to a -QH group, and

(II) a mono- and / or polycarboxylic acid with 2 to 14, preferably J5 to 12 carbon atoms per molecule, with the following dissolved in the base oil:

(a) 0.005 to 0.15 wt. #, preferably less than 0.08 wt. ^, of a dicarbon hydrogen phosphate of the formula (RO) ₂ P (O) OK, in which R (which do not necessarily have to be the same in any given molecule ) alkyl, cycloalkyl, aryl, alkaryl or Äralky! groups having up to 20 carbon atoms and preferably Alkylodei Cyeloalkylgruppen * having up to 10 carbon atoms, such as butyl _P 'J ^ Jithylhexyl or cyclohexyl, are

(b) 0.005 to 1.5% by weight, preferably 0.01 to 0.5% by weight, a copper passlivator and

(o) 0.5 to 6.0, preferably 2.5 to 5% by weight, of an aromatic Amine antioxidant "

0098 3 8/1718

The concentrations of the additives given in this description are based on the ester. Of course the mixture can have more than one element of each group contain the mentioned components.

Copper passivators are well-known materials that have the function of «.the extent to which corrosive substances Attack copper, decrease. The copper passivating agent used in the mixtures according to the invention must naturally be soluble in the base oil. This means has the purpose of reducing the corrosion of the materials used in engine parts if they are used for a long period of time at high temperatures and exposed to the lubricant in the presence of air. The effectiveness of metal passivants can be measured by corrosion tests, through which the protection of metallic parts can be recognized. With such In tests, copper is the most critical metal and it has been found that if passivation is effective of this metal the corrosion of the other metals used; is negligibly low * The exception here is lead. Suitable groups of copper passivators include:

1. those of the azoles, such as xmidazole, pyrazole, Triazole and its derivatives, e.g. benzotriazole, methylbenzotriazole, Xthylbenzotriazole, butylbenzotriazole, dodecylbenzotriazole, Methylene-bis-benzotriazole and maphthotriazole.

2. Salicylaldehyde semicarbazone and its CL- to C ₂₀ -alkyl derivatives, for example methyl- and isopropyl-salicylaldehyde semicarbazone.

3. Condensation products from salicylaldehyde and hydrazine derivatives and fatty acid salts of such condensation products · A particularly suitable hydrazine derivative is Aminoguanidines while as fatty acids those with 2 to

24 carbon atoms are suitable.

009838/1718

Particularly effective copper passivating agents are methylenebisbenzotriazole and the salts of 1-salieylalaminoguanidine and fatty acids with Γ5 to 18 carbon atoms, such as palmitic acid.If the Sehmierraittelgeraiseh is intended for use in engines with components made of lead alloys, it is desirable to add a corrosion inhibitor to the mixture. . generally in a concentration of 0.01 to 1.0, preferably 0.05 to 0.25 wt Suitable lead corrosion inhibitors are C ^ - to C _2Q -AlkylgallussSureester (e.g. propyl gallate), & Neopentylglykoldisebaeins acid esters, sebacic acid and quinizarin. Propyl gallate is preferred; it does not affect the other properties of the lubricant.

Suitable aromatic amine antioxidants include phenothiazines, iminodibenzyl, diphenylamine, phenyl-α-naphthylamine and phenyl-β-naphthylamine.wiMl The alkylated (for example C 1 -C alkylated) aromatic amines and especially those of the formula R ¹ C ₆ H _{4 are particularly suitable} NHC ₆ Hj ₁ R ¹ , where R ^{1 are} alkyl groups with up to 14 carbon atoms (not necessarily the same in every given molecule) and in particular octyl or nony groups. p, p ^l -Dioctyldlphenylamine is particularly effective. Other particularly suitable alkylated aromatic amines are the mono- and di-C ₁ to C 1-4 alkyl (for example dioctyl and dinonyl) phenothiazines, iminodibenzyls, diphenyl-p-phenylenediamines and phenynaphthylamines. In certain cases it may be desirable to use an antioxidant mixture, for example a mixture of an alkylated diphenylamine (e.g. dioctyldiphenylamine) and an alkylated phenylnaphthylamine (e.g. a mono-oxy-phenylnaphthylamine).

in this description used term "polyester * an ester having at least two Esterbindungen depending Moletau,) Oer Auedruck ^1" esterifiable neutral "refers to a fully

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tth product. Of course, more than one of the reaction components mentioned can be used in the above-mentioned esterification reaction can be used, for example a mixture of monocarboxylic acids in which case the neutral ester product the esterification reaction sometimes consists of a mixture of different ester molecules, so that the expression "Polyester" is to be interpreted from this point of view.

Polyesters which are particularly suitable as base oils for high temperatures in the mixture according to the invention are products made from the following acids and alcohols: caprylic acid, capric acid, caproic acid, oenanthic acid, Pelargoö », valeric acid, pivalic acid, propionic acid, butyric acid, 2-ethyl-caproic acid, adipic acid, sebacic acid, azelaic acid, 2,2,4-trimethylpentanol, neopentyl alcohol, Neopentyl glycol, triraethylolethane, trimethylolpropane, pentaerythritol and dipentaerythritol.

Examples of such particularly suitable polyesters are:

(a) Esters of trimethylolpropane, trimethylolethane, pentaerythritol and / or dipentaerythritol with one or more monocarboxylic acids with 2 to 10 carbon atoms, in particular of the type described in the previous paragraph, and

(b) Complex esters of methylolpropane, sebacic acid and / or azelaic acid and one or more monocarboxylic acids with 3 to 10 carbon atoms, especially of the kind described in the previous paragraph. Best will Trimethylolpropane and dicarboxylic acid in a molar ratio of 1: 0.05-0.75, preferably from 1 t 0.075-0.4, for Brought reaction, the monooarboxylic acid amount is sufficient, to achieve a carboxyl / hydroxyl equilibrium in the To trigger reactants »

009838/1718

The good wear resistance and resilience properties the mixtures according to the invention can still be obtained by adding a neutral phosphate of the formula (R O) JPO

2 2

improve further, where R are alkyl, cycloalkyl, aryl, alkaryl or aralkyl groups (which need not necessarily be the same in any given molecule) and where the total number of carbon atoms in the molecule is jj to 60, preferably 3 to JQ . The proportion of such a neutral phosphorus compound should constitute 0.01 to 10, preferably 0.5 to 5 wt.% Of the mixture. Preferred

ρ neutral phosphates are those in which B is alkyl or Cycloalkyl groups with up to 10 carbon atoms, for example phenyl, tolyl or xylyl groups.

Examples

A number of mixtures according to the invention and also a number of comparison mixtures have been tested for wear or pressure absorption properties using the well-known ΪΑΞ gear machine and anti-corrosion properties and resistance to oxidation under high temperatures as part of an oxidation / corrosion test. The tests corresponded to the official specifications and those of the manufacturers of engines for lubricants for use in engines for modern jet aircraft.

In the gear wheel test, the lubricant to be tested was sprayed at a temperature of 200 ^° C. onto a set of gear wheels which were driven at a speed of 2,000 revolutions per minute, while force was applied via a loaded lever arm. As soon as the gears were pressed, the load on the lever arm was registered.

009838/1718

In the case of the oxidation / The oil was subjected to a corrosion test for 48 hours in the presence of five metals and with one pearling through the oil Air flow of 5 liters / hour at a temperature of 28 ° C held. The metal weight changes and the increase in viscosity and acid value of the oil were measured. the The purity of the oil was determined by Kessen as part of this test the amount of insoluble matter formed was also determined.

The following were used for the lubricant mixtures tested Base oils used:

A - A complex ester produced by the reaction of caprylic acid, 1,1,1-trimethylolpropane and sebacic acid im Molecular ratio of 28 s 10: 1 under esterification conditions and using a catalyst was produced.

B - A mixture of four parts by weight of a neutral ester of pentaerythritol and a mixture of straight-chain C, -C "-monocarboxylic acids with a weight fraction of a neutral ester of dipentaerythritol and the same mixture of carboxylic acids.

The following additives were used in the mixtures:

DBHP - dibutyl hydrogen phosphate:

SAGP »Salt made from 1-salicylaldehyde aminoguanidln and one

Mixture of fatty acids with 13 bla 18 carbon atoms.

MBBTZ »methylene-bis-benzotriazole.

Antioxidants:

In all cases it was a mixture of 3 parts ρ, ρ'-dioctyldiphenylamine and

009838/1718

TTP
PG

1 part monooctylphenyl-ß-naphthylarain. This has been found to be the best combination in terms of purity in both long and short-term oxidation tests.
Tritol! Phosphate.
Propyl gallate.

The lubricant mixtures used in the tests are shown in Tables 1 and 2. The numbers are based on parts by weight.

Table 1 Composition of mixtures according to the invention

composition 1 100 2 100 - 100 100 5 6th - 7th Base oil A '- 0.02 - - 100 - 4.0 - Base oil B 0.02 0.1 0.02 0.02 - 100 - 100 DBHP 0.1 - 0.1 - 0.02 0.02 0.1 0.02 SAGP - 4.0 - 0.02 - 0.1 0.1 MBBTZ 4.0 - 4.0 4.0 0.02 - Antioxidant
middle - 0.1 2.0 2.0 4.0 4.0 TTP - 0.1 0.1 2.0 2.0 PG - 0.1

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Table 2 Composition of the comparative mixtures

Together
settlement 21 22nd 25th 24 25th 26th - 27 4.0 28 29 - 4.0 Base oil A 100 100 100 100 100 0.1 2.0 - - 2.0 Basic B - - «· • - 100 100 0.1 100 100 0.1 DBHP - - 0.02 - - - 0.02 SAOP 0.1 - - 0.1 - 0.1 - 0.1 Antioxidants
media 4.0 4.0 4.0 4.0 4.0 4.0 4.0 TTP IF 2.0 2.0 2.0 2.0 2.0 PO 0.1 - 0.1 0.1 0.1 0.1

The results of the tests are recorded in Tables 3, 4 and 5 .

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- ίο -

Table 3

Loadability and pressure absorption test

Addition Pressing load
kg 21
1
2 16.8
29.5
28.1 24
3 16.3
36.3 26th
6th 18.6
24.9 28
7th 20.0
29.5

The superior over-absorption properties of the Mixtures of the invention contain minor amounts of dibutyl hydrogen phosphate in comparison to the other mixtures are clearly recognizable.

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! EABELLE 4 Oxidation / Corrosion test

Together
settlement ViskoBitate-
increase in Acid addition
took M. G Metal weight change Ott Ag 3
3 Fe 3
3 Insoluble
Fabrics 37.8% in i> mgKOSVg +0.
-O. 3 to
3 Al up to +0,
-O, to + 0 *
until
-O. +0.
until
-O. in mg Wishes-
verte
Sizes nuuc. 50 ' max. 5 +0.
-O, - .3
.3 .3
, 3

O
σ 22nd 45 1.7 -0.03 -0.01 -1.14 -0.13 -0.03 0 I. OO
cn co
co 23 53 3.5 -0.02 no -0.75 -0.05 -0.1 0 I.
kJ
H CaJ
CO 25th 44 3.6 -0.03 -0.01 -1.14 -0.13 -0.03 0 I. ^ v
λ
-J 2
3 35
40 1.3 '
2.5 -0.04
no -0.03
-0.01 -0.07
-0.09 -0.12 -0.04
-0.06 +0.01 0
O OO 4th 38 2.2 no +0.02 +0.02 -0.05 +0.06 O 5 36 3.0 no +0.3 no -0.03 +0.04 0 27 64 1.7 no -0.06 -1.81 -0.11 -0.03 0 29 56 1.8 -0.05 -0.01 -0.89 -0.10 none 0 6th 36.5 0.5 no -0.04 -0.12 -0.12 -0.01 0 7th 45 1 7 -0.03 -0.02 -0.15 -0.13 +0.03 0

.is. 16U861

The results shown in Table 4 show the exceptional high resistance to oxidation and corrosion as well as the outstanding purity of the lubricant mixtures according to the invention.

Mixtures 2 to 7 gave far better results in these tests than mixtures 22, 2 $, 25, 27 and 29,
which did not contain a copper passivator "

Table 5 below shows that the substantial improvement in load-bearing capacity achieved by adding small amounts of dibutyl hydrogen phosphate without any noticeable impairment of the oxidation / corrosion properties of the mixtures
going on.

00983 3/1718

Table 5

GtoJBiseh 28 Fresas
load kg Viscosity
increase in Acid to
took Mg Metal weight change
mg / cm * ² Al Cu Ag Fe Insoluble
Fabrics 37.8 ⁰ C in % mgKOH / g -0.04
-0.02 -0.03
-0.03 -0.07
-0.09 -0.12
-0.06 -0.04
-0.03 in mg 2
21 28.1
16.8 35
39 1.3
2.7 «0.06
no -0.06
-0.01 -0.12
-0.09 -0.09
-0.06 no
+0.01 0
0 3
ο 36.3
16 * 3 41.7
40 4.8
2.5 no
+0.01 -0.04
no -0.12
-0.11 -0.12
-0.03 -0.01
no 0
0 co
OO 24.9
18.6 36.5
38 0.5
1.25 -0.05 -0.02
-0.02 -0.15
-0.09 -0.13
-0.08 +0.03
-0.02 0
0 29.5
20.0 45
38 1.7
3.3 0
0

Η »VjI

CD JO-

Claims (1)

Claims 1.) Lubricant mixture based on synthetic lubricants, characterized in that the base oil consists of one or more liquid neutral polyesters which by reaction in one or more stages under esterification conditions from (I) a mono- or polyhydric alcohol with 5 to 15 carbon atoms per molecule, with no water * .- - *. .r «& £ P $ ⁿ carbon atom in the 2-position / bonded to an -OH group, and (II) a mono- and / or polycarboxylic acid with 2 to 14 Carbon atoms per molecule, where are dissolved in the base oil * (a) 0.005 to 0.15 wt. # of a _{dihydrocarbyl hydrogen phosphate of the formula (RO) 2} P (O) OH, in which R (which need not necessarily be the same in any given molecule) is alkyl, cycloalkyl, aryl, alkaryl - or aralkyl groups with up to 20 carbon atoms, (b) 0.005 to 1.5 wt.% of a Kupferpassivators and (c) 0.5 to 6.0 wt% of an aromatic amine antioxidant. 2.) Lubricant mixture according to claim 1, characterized in that the polyester is an ester of trimethylolpropane, Trimethylolethane, pentaerythritol and / or dipentaerythritol and one or more monocarboxylic acids with 3 to 10 carbon atoms is « 2.) Sohraierraittelgeraiach according to claim 1, characterized in that that the polyester is a complex ester of trimethylolpropane, sebacic acid and / or azelaic acid and «iner or several monocarboxylic acids with 2 to 10 carbon atoms is. 00 9838/1718 INSPECTED 4.) lubricant according to claim 1 to 3 »characterized in that it is a bicarbonate hydrogen phosphate of the formula (RO) ₂ P (O) OH, in which R is alkyl or cycloalkyl groups with up to 10 carbon atoms, for example butyl, 2- Xthylhexyl or cyclohexyl, contains, the amount of phosphate between 0.005 and 0.08 Gew.Ji. 5.) lubricant device according to claim 1 to 4, characterized in that that it is methylene-bisbenzotriazole as a copper passivator or a salt of l-salicylaldehyde aminoguanidine and one or more fatty acids with 13 to Contains 18 carbon atoms, where the amount of copper passivators between 0.01 and 0.5 wt. 6.) lubricant mixture according to claim 1 to 5, characterized in that that the antioxidant used is an alkylated aromatic amine of the formula R CgH ^ NHCgH ^ R, in which R Alkyl groups with up to 14 carbon atoms are, if possible, in a mixture with a mono- or di-C to C _lJtl -Alkylphenylnaphthylamin contains. 7.) lubricating oil mixture according to claim 1 to 6, characterized in that that it contained a lead corrosion inhibitor in an amount of 0.01 to 1% by weight. 8.) Schmienaittelgemiech according to claim 1 to 7, characterized in that that there are 0.01 to 10, preferably 0.5 to 5.0 weight, £ «Ines neutral phosphate of the formula (R O) -PO, in which R is alkyl, cycloalkyl, aryl, alkaryl or aralkyl groups with a total number of 3 to 60, preferably contains up to 10 carbon atoms in the molecule. 009833/1718