DE1912672A1 - Lubricant compositions - Google Patents

Description

The invention relates to lubricants' Sira gene, which essentially eus a flowable. Söhmiermittel'be.sis and a smaller amount of an oet ^; 'lphenyl-ana.phth lamin-Dioct \ Idiphenylamine combination exist as an antioxidant.

The antioxidants according to the invention are in particular for high-temperature lubricants based on synthetic esters for aircraft turbo-prop and turbo-jet engines suitable"

Although the G-rest resistants are on the B'isis more synthetic Esters have proven to be superior to mineral oils, the modern aircraft to come will require the modification the lubricant based on synthetic esters with Additives to obtain lubricants that also stop at temperature are effective above about 205 ° C. One problem with the high temperature lubricants is> that. at temperatures above about 205 ° C to rubber 'and mud'

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tend to form, which greatly accelerates engine wear and if it is not kept under control, the Kotoren can fail. It was already a number of amines, sulfides, etc. are used as antioxidants to prevent the formation of gums and sludge. However, it has been found necessary to develop better antioxidants and lubricants in order to to meet the constantly changing requirements of 3? aircraft engines. A solution to this problem consists in the search for synergistic mixtures of Antioxidants. A successful combination of antioxidants is that disclosed in the US patent 3 247 111 described combination of phenyl-a-naphthylamiri and DiQCt./ldiphenylamine represent «

It has now been found that a combination of the antioxidants Octylphenyl-a-naphthylamine and diootyl * Diphen; ylamine in lubricants significantly reduces the formation of sludge and oil at temperatures above approx. 205 ° C and thus meets all requirements for industrial and military use * In addition can the antioxidants according to the invention in the usual flowable lubricant bases ausammeη with the numerous additives used in aircraft engines be applied"

The antioxidants of the invention can by the following general lörmelh are reproduced

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and R

in which the substituents R represent identical or different branched-chain octyl radicals. With -the preferred Compounds are tertiary octyl groups in the p-position of the phenyl ring.

The compounds mentioned can by reacting diisobutylene with phenyl-a-naphthylamine or diphenylamine in the presence of a Friede! Grafts catalyst, such as boron trifluoride, can be produced. In general, the commercially available diisobutylene used as the reactant consists of a mixture of about 80 fo

? ^H 3 -jp 2 H ₅ CC-CH ₂ -C-CH-CH ₅

and about 20 ⁰ J ₀ CH ^ -C-CH = C

₅ -C

CH ₅

Accordingly, the reaction products consist of one Mixture of compounds with branched octyl groups, although the compounds with tertiary octyl groups in predominate in the p position. In the present case, the term denotes Dioctyldiphenylamine and octylphen rl-oc-naphthylamine the aforementioned reaction products.

In general, the lubricants according to the invention contain a larger amount of a flowable lubricant

tel base and a smaller one sufficient to inhibit oxidation Amount of antioxidants according to the invention.

41/1324

Usually the concentration of antioxidants is about 0.25 to about 5% of the fluid base lubricant. A preferred range is from about 0.5 to about 1.5% by weight. Preferably the two are antioxidants according to the invention present in approximately the same amounts, but with many applications corners will also be satisfactory Results obtained with a ratio of antioxidants from about 4: 1 to about 1: 4. Although the reason for the effect achieved according to the invention is not known, it is clear that with the combination of the antioxidants significantly better results can be achieved than with a comparable amount of the individual antioxidants.

The antioxidants according to the invention can be used in the usual flowable basic materials, made up mainly of carbon, hydrogen and oxygen atoms exist. Both mineral oils and synthetic materials and their mixtures can be used will.

The lubricants .8, on the base are particularly suitable of esters. These can be simple diesters of a dibasic acid and a monohydric alcohol or polyesters made from polyhydric alcohols and monobasic acids or polyesters made from polyhydric alcohols and polybasic acids with reactive hydroxyl and / or carboxyl groups or polyesters made from polyvalent ones Alcohols and polybasic acids act in which the hydroxyl and carboxyl groups are reacted with raonofunctional alcohols and / or acids.

The dibasic acid esters have the general formula

ROCG (C _n H _2n ) COOR

00 9841/1324

in which η is an integer τοη 2 "to 18 and the substituents R are identical or different, cyclic or acyclic alkyl radicals having 3 to 18 carbon atoms.

Examples of such acids that can be used are succinic acid, Pimelic acid, sebacic acid, glutaric acid, suberonic acid, undecanedioic acid, Adipic acid. Azelaic acid, dodecanedioic acid and octadecanedioic acid.

The alcohols used for the formation of the diesters can be used branched or straight-chain, saturated or unsaturated, aliphatic or cycloaliphatic. Typical examples are 2-ethylhexanol, amyl alcohol, 2-ethylbutanol, oleyl alcohol, ethyl? alcohol, 2 ~ butyl octanol, n-octanol, i-ethylcyclohexanol and uimethylcyclohexanol.

■■ Roman esters can also be used. They have the general formula Z (COOR)., In which n ^{1 is} an integer from 1 to 4, a benzene or japhthene radical and R has the meaning given above. Examples of suitable aromatic acids are phthalic acid, pyromellitic acid, terephthalic acid and japhthylene-1,4-dicarboxylic acid

The polyalkylene glycol esters used can be represented by the following formula:

0. 0 R ^ CO- (UR ^) _x -OC-IT

in which x is an integer from 4 to 100, the substituents

R cyclisohe ode. ;; Classic alkyl radicals with 5 to 18 carbons Substance atoms and R hydrogen, the methyl or ethyl radical are .

ueeir -;, some other rolyalivylene glycol esters have the same generalities Formula:

a O 9 β 41/13 2 4

δ.

δ.

R ^K -C-0-

ι ι

C-C-O

0
., CR ⁴

in which R ^{4 is} a cyclic or acyclic alkyl radical with 4 to 24 carbon atoms. ~ fe? * "means Jp hydrogen, the methyl or ethyl radical, and x ¹ is an integer from 4" to 79.

Other useful esters are made from a monobasic acid and a polyol and have the general formulas:

~ 0
Il

CH ₂ OC- (CH ₂ )

and

R ⁶ -C

J-CH ₂ OC- (CE ₂ ) _y OH ₅

in which y is an integer from 0 to 12 and R is an alkyl radical having 1 to 12 carbon atoms.

In addition to the above-mentioned esters, polyethylene glycol ethers can be used be used. They have the general formula

R ⁷ -0-

i I

C-C-ü-

in which y is an integer from 2 to 70, R ^ Wasserstaff, ·

7th
the ethyl or ethyl radical and R ^{1 is} a cyclic or acyclic alkyl radical having 1 to 12 carbon atoms.

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Other suitable esters are obtained from polyhydric alcohols and monobasic acids. Examples of suitable Alcohols are feopentyl glycol, trimethylolethane, trimethylolpropane and lentyerythritol. Suitable monobasic acids are straight-chain and branched * aliphatic, cycloaliphatic and aromatic acids and mixtures of these acids. Typical acids are acetic acid, butyric acid, Valeric acid, isovaleric acid, heptanoic acid, Caproic acid, pelargonic acid, decanoic acid, benzoic acid, dodecylbenzoic acid, Naphthenic acids, cyclohexylacetic acid, etc.

Other esters that can be used have the general formula

O · O H il

A-C-O-P-ü-C-B

in which P is an arylene radical, namely resorcinol or bisphenol and A and B are each phenyl,

CH, - (CH ₀ -) ,, - or

(CH ₂ ) _n - C -

CH ₃

mean, where η is an integer from 0 to 5.

Examples of esters of the general formula given above are: resorcinol dipivalate, resorcinol diheptanoate, bisphenol diheptanoate, Resorcinol dineodecanoate, resorcinol dibenzoate, resorcinol benzoet neoheptanoate, bisphenol dibenzoate and resorcinol dibenzoate.

The antioxidants according to the invention can be used together with the numerous usually in SchTKiermittein

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1912671

used additives are used, e.g. with agents., which lower the pour point (e.g. polyalkyl methacrylates and dialkyl fumarate), load-carrying additives (■ e.g., aryl phosphates and alkyl-substituted aryl phosphates, including iriphenyl phosphate, phenyl dicresyl phosphate, Ericresyl phosphate and methyl di-tert-butyl phosphate), Dispersants (e.g. butyl methacrylate polymers), rust inhibitors (e.g. petroleum sulfonates), agents that improve viscosity (e.g. polybutene, alkylatedi Polystyrene and polyalkyl methacrylates), thickeners !! (e.g. calcium stearate and polyesters), and metal inactivating agents (e.g. quinizarine, benzotriazole and saturated aliphatic dicarboxylic acids with 6 to 10 carbon atoms including adipic acid, sebacic acid., pimelic acid and suberonic acid). In general, only small amounts of about $ 0.001 to about $ 5 of each additive are used.

The antioxidants of the invention can also be used in fat compositions, puncture fluids and whole are generally used in applications that are subject to high temperatures. The terms "lubricant" and "lubricant additive" used herein amme ns et sung "should include these purposes.

As usual, the lubricants can be mixed thoroughly the components including the additives at room temperature or at a slightly elevated temperature (up to about 150 ° C),

Lim the effectiveness of the antioxidants according to the invention They are found in various oils and 'synthetic materials with and without additives the leathereral standards 791-5308 method high temperatures exposed. This method consists in that the lubricant

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medium up to 72 hours temperatures from 175 to 232 ° C suspends and then the lubricant for changes in its physical properties investigated. The mud will removed by passing the lubricant through a 7 ^ i * filter filtered according to ASTM Db * 1-61.

The following examples illustrate preferred embodiments of the invention. All specified parts are weight parts represent.

example 1

The following ingredients are made by mixing thoroughly at temperatures of 80 to 150 G into a homogeneous mixture transferred.-

Parts

76.68 oleic acid ester of trimethylolpropane 20.00 dietary hexyl adipate 1.00 octylphen.yl-ii-rnaphthylamine 1.00 dioctyliphenylamine

1.32 v / other additives for the incorporation of corrosion inhibitors, carrying additives and dispersants.

Composition was made according to Federal Standards 7 ^ 1 -5308 ! • method temperatures from 175 to 232 C for 72 hours exposed. The lubricant was then filtered to remove any sludge formed, but none became Found mud.

The Zusammensetzünden the following B _e ispiele were prepared according to the procedure of Example 1 and examined 791-5308 method according to the Federal standards. The compositions of Examples 4, 5, 6, 7 and 8 were subjected to the test described in Example 1. They did not lead to a slump formation. The compositions of Examples 2 and 3 were kept at temperatures for 48 hours

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- ίο -

from 218 to 232 ° C. They didn't show any either Sludge formation. .->. '"

Example 2

Parts . _. . '.

19.52 C ₇ acid ester of trimethylol propane

78.02 Mixture of C. to C ^ acid esters of pentaaerithritol 1.15 Oct O-phenyl-a-naphthylamine

1.00 dioctyldiphenylamine ■ -

0.31 further additives for the incorporation of load-bearing agents and corrosion inhibitors

Example 3 parts

67.90 Mixture of G 1 to C ^ acid esters of pentaerythritol 28.29 Cy acid esters of trimethylolpropane

1.00 Dioctyldiphenylamine 1.00 Mixture of CU to CJQ polyalkyl methacrylates 1.50 Oct ¹ phenyl-a-naphthylamine

0.31 further additives for the incorporation of load-bearing agents and corrosion inhibitors

Example 4 parts

99.69 Mixture of C ₅ - to Cg acid esters of trimethylolpropane -. "-". ·

ο.5 octylphenylöttiaphthylamine

0.5 Dioct 1-diphenylamine _: .;

1.00 Mixture of CU to C.Q polyalkyl methacrylates

0.31 further additives for the incorporation of load-bearing agents and corrosion inhibitors ^: '''^;

9098-1 / 1324

Example 5 parts

96.69 Mixture of Gg to OQ acid esters of trimethylol

propane

1.00 Qetylphenyl-a-naphthylamine-1.00 Dioetyldiphenylamine

1.00 Mixture of G, - to G-jQ-PolyalkylmethaGrylaten 0.51 additional additives for the incorporation of carrying agents

and corrosion inhibitors

Example 6 parts

86.69 mixture of Gp- to Gg-acid esters of trimethylol-

propane

10.0 di-2-ethylhexvladipate
1.0 dioetyldiphenylamine
1.0 octylphen, 1-a-naphthylamine
0.31 further additions ^ for the incorporation of supporting means

and from corrosion inhibitors 1.00 mixture of .0, - to G ^ p-PolyaiiiBylmethacrylaten

Example 7 parts

78.00 enoic acid ester of trimethylolpropane 20.00 di-2-ethylhexyl adipate

1.00 dioetyldiphenylamine

1.00 octylphenyl-ctr-naphthylamine

Example. 8 ·

Parts

67168 Go-T acid ester of trimethylpropane 30.00 pir-2-ether-hexyladipate p, | p Det; ^: l-phenyl-a-naphthylamine

0.50 dioctyldiphen, '

0.32 further additives for the incorporation of carrying agents

and of corrosion inhibitors 1.00 mixture of C1-10 polyalkyl methacrylates

The following tests were carried out to compare the action of the antioxidants according to the invention with the combination of dioctyldiphenylamine and phenyl-cc-naphthylamine mentioned. The lubricants were prepared by mixing the individual ingredients at a temperature between about 80 and 150 ° C. until the compositions were homogeneous. The lubricants were then subjected to the Alcor Inc. High Temperature Deposition Test, which consists of circulating the compositions to be tested with air through a heated metal tube. The temperature of the pipe is constantly increased until a sludge deposit is found. This temperature, which is called the critical temperature, is recorded in Table I below, together with the layers formed. The results obtained show that the antioxidants according to the invention are effective at higher temperatures than the known combination. In addition, the "total deposit" is considerably lower than with the known combination. Regarding the developed part, reference is made to the Proceedings of the LS Air Force, Southwest Research Institute Turbine Engine Conference (1S'G7).

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Table I. Results of the comparative tests

Composition Example 9 Comparative Example 10 Comparative

try A try B

Trimethylene propane triheptanoate

⁰⁰ Di-2-äthvlhex7ladipat

cd Cctylphen ^ l-a-naphthylamine

^ Dioctyldiphen-lamin

hen; 1-a-naphthylainin

- * further additions for the incorporation of carrying agents

⁰ ^ and of corrosion inhibitors

■ e- mixture of C, - to C ^ Q-polyalkyl methacrylates

Alcor deposit test

ir, ° C total deposits

critical temperature, C

Parts Parts Parts Parts 76.68 76.68 67.68 67.68 20.00 20.00 30.00 30.00 1.00 - 0.50 - 1, 00 1, 00 0.50 0.50 - 1, 00 - 0.50 _α 0.32 0.32 0.32 0.32 , 1, 00 1.00 1.0.0 1.00 ■> 316 288 > 316 299 ■ 24.7 49 22.1 51.7

Claims (7)

Claims 1.j Lubricant composition, consisting essentially
^ chen from a flowable lubricant base and a smaller amount of an octylplienyl-a-naphthylamine-dioctyldiphenyla'min Combination as an antioxidant, 2. Composition according to claim 1, characterized in that the ratio of Oetylphenyl-a-naphthylamine to dioctyldiphenylamine about 4: 1 to about. 1: 4 ". 3. Composition according to claim 1, characterized in that that the flowable lubricant base consists of a dibasic ester of the general formula ROOO (CnH ₂ n) COOR consists in which η is an integer from 2 to 18 and
the substituents R are identical or different cyclic or acyclic alkyl radicals with 5 to 18 carbon atoms, 4. Composition according to claim 1 , characterized in that the flowable lubricant base is an ester of a polyhydric alcohol and a monobasic acid. 5. Composition according to claim 1, characterized in that that the flowable lubricant base consists of a mixture of synthetic esters, 6. Composition according to claim 1, characterized in that the concentration of the antioxidants
about 0.25 ° to about 5 ° based on the weight of the lubricant. 909841/1324 7. Composition according to claim 1, characterized in that that the concentration of the antioxidants is about 0.5 "to about 1.5% by weight of the lubricant, Pure Stauffer Chemical Company Hew: 'ork, N.Y. , V.St.A. Lawyer 909841 / 132A