DE944624C - Lubricant based on esters of phosphoric acids, silicic acids, carboxylic acids and compounds with linear polymeric chains - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

ISSUED JUNE 21, 1956

GERMAN PATENT OFFICE PATENT LETTERING

CLASS · 23c GROUP 1 οι INTERNAT. CLASS C 10m

Ή 7118 IVc12SC

Forrest Jay Watson, Emeryville, Calif. (V. St. A.)

has been named as the inventor

N. V. De Bataafsche Petroleum Maatschappij, The Hague

Lubricants based on esters of phosphoric acids,

of silicas, carboxylic acids and compounds

with linear polymer chains

Patented in the territory of the Federal Republic of Germany from May 1, 1953 Patent application published December 8, 1955

, Patent granted on May 30, 1956 The priority of the application in the V. St. v. Claimed America May 2, 1952

The invention particularly relates to high quality composite lubricants, in particular which for use as hydraulic fluids or as lubricants for internal combustion engines are suitable and which are resistant to degradation by oxidative or thermal influences and have exceptional corrosion properties.

According to the invention the intended aim is achieved by o esters of phosphoric acids, silicic acids, carboxylic acids or suitable for this purpose, long chain polymeric compounds minor amounts of a Epoxyverbindug and a metal salt incorporated into the \ used as a lubricant based on a condensation product of an aldehyde and a phenol or thiophenol. The two

Additives are intended essentially with the lubricant base be mixable.

The use of metal salts of the condensation products from aldehydes and phenols or thiophenols as a lubricant additive was per se known. It has also been proposed to use polymerized epoxy compounds themselves as a lubricant base.

However, the combined use of the two components creates a synergetic effect achieved, which could not be foreseen due to the effect of one of these additives. Mixtures with the most favorable properties are obtained by adding each of the additives in an amount from 0.1 to 6 percent by weight, particularly expediently 0.5 to 2.5 percent by weight, calculated on the Total mixture, used.

Epoxy compounds are organic compounds which ι an oxygen atom in bond Contain 2 carbon atoms, which in turn are already connected to one another in another way. As epoxy compounds which are effective in the mixtures according to the invention, for example the following are listed: pinene oxide, butadiene oxide, i, a-epoxy-s-aminopropane, Glycidyl phenyl ether, epichlorohydrin, 2,3-epoxy-4-chlorobutane.

Polyepoxides, d. H. Compounds containing more than one epoxy group can also be used will. These can be monomeric compounds that have more than one epoxy group, or polymerized compounds. The latter compounds can be of any one the monomeric monoepoxides and some of their epoxy groups may be hydrated or implemented in some other way. You can have molecules with slightly different molecular weights contain.

Examples of this type of compound include the glycidyl polyethers of the polyvalent,

z. B. dihydric phenols are expected, the by reacting a polyhydric phenol

with a large excess, e.g. B. an excess of 4 to 8 moles of a halogen-containing epoxy in alkaline medium.

The other additive is a metal salt of a condensation product of an aldehyde and a phenol or thiophenol. Suitable phenols and thiophenols, of which the condensation products derive, are for example dibutylthiophenol, amylphenol, octylphenol, octylthiophenol, p-isooctylphenol, alkylaminophenol, alkylaminonaphthol and the like

Aliphatic, aromatic or other cyclic aldehydes can be used to form the condensation products with the abovementioned compounds. Examples of suitable aldehydes are formaldehyde, acetaldehyde, crotonaldehyde, butyraldehyde, benzaldehyde and furfuraldehyde. 6.0 The condensation products can according to known; Process using an acidic or a basic catalyst can be prepared. As salts _{: of} the condensation products mentioned, alkali, alkaline earth or heavy metal salts come into consideration, for example the Ca, Ba, Sr, Na, K, Li, Al and Zn salts.

The phosphorus-containing esters, which are used as a lubricant base, useful within the present compositions include those normally liquid aliphatic Esters of acids of phosphorus, for example hydrocarbon phosphonic acid dialkyl ester, in particular dialkyl alkylphosphonates, dialkylphosphinates containing 2 phosphorus atoms Compounds such as bis (dialkylphosphonic) alkanes and the corresponding ethers of the aforementioned Diphosphorus compounds.

The phosphorus-containing esters, which are particularly suitable for the combination of additives according to the present invention, usually have ' at least 18 total carbon atoms and preferably about 20 to 32 carbon atoms in the Molecule, for example, phosphoric acid trihexyl ester, phosphoric acid tri (isooctyl) ester, phenylphosphonic acid dihexyl ester and hexyl diheptylphosphinate.

The compounds containing 2 phosphorus atoms include, in particular, aliphatic hydrocarbons, which by two phosphorus-containing groups in the form of phosphate, phosphonate, phosphate or phosphine oxide groups are substituted. Reference go borrowed from the hydrocarbons bearing the latter type of substituent can be noted that these are not esters in the real sense of the word: they are, however, the other compounds analogously and, like these, can be used as a lubricant base in the mixtures according to the invention will.

It is of course not necessary to use connections with a symmetrical structure. For example, the various substituents within a particular compound can be different be, both in terms of the content of carbon atoms and in terms of the spatial configuration. The branched structures are preferred because they are generally have a better effect on the lubricant properties, especially at low temperatures. Unsaturated hydrocarbon radicals are particularly desirable when attached directly to a phosphorus atom are bound because their presence has been shown to reduce the corrosion properties of the lubricant improved.

The class of compounds containing 2 · phosphorus atoms have favorable properties with respect to of use as hydraulic fluids. In general, their viscosities are between 10 and 25 cSt at about room temperature. The compounds in which 2 carbon atoms are direct are connected to one or both phosphorus atoms, in particular the diesters of alkanediols and Dialkylphosphinic acids, have much higher viscosities, which makes them more than synthetic lubricating oils are particularly suitable.

Another suitable lubricant base are the esters of organic carboxylic acids, especially those complete esters of aliphatic dicarboxylic acids,

For example, adipic acid di (2-methylheptyl) ester, dioctyl phthalate, sebacic acid di (2-ethylhexyl) ester, Allyl caprylate, as well as their homologues, analogues and derivatives. Tri-esters such as B. trioctyl aconitate, are also well suited.

Silicic acid esters also behave very favorably in relation to the incorporation of the combined additives according to the present invention. The silicic acid esters include alkyl, aryl, aralkyl and alkylaryl esters of silicon-containing acids, such as ortho-, metha- and polysilicic acid esters. Typical examples from This group includes tetra (2-ethylhexyl) silicates, tetra-phenyl silicates and tetracresyl silicates and tetradecyl silicate.

Particularly suitable esters are also made by esterifying acids of silicon and phosphorus or obtained from polycarboxylic acids with sulfur-containing alcohols. The esters thus obtained have excellent properties at high pressures, and they speak to the combined according to the invention Additives particularly well.

Compounds with polymeric linear chains, the exist as oxyalkylene units.

The typical formula of such polymers is

where η is an integer and R is an organic radical. In these polymers, all or some of the oxygen atoms can be replaced by sulfur atoms. Polymers of this group can be prepared by polymerization or copolymerization of alkylene oxides, glycols and sulfur-containing analogues thereof.

In addition to the additives combined according to the invention, smaller amounts of other additives can be added to the Lubricant mixtures are incorporated in order to improve certain properties of the same. Examples for such additives are the polymerized methacrylic acid esters (which come under the trade name »Acryloick are marketed), 2, 6-di-tert-butyl-4-methylpb.enol, phenyla-naphthylamine and bis (p-dimethylaminophenyl) methane.

To get the synergetic effect created by using the two additives together in is achieved with the mixtures according to the invention, two types of tests were used.

According to experiment A, carefully cleaned and polished metal sheets made of a magnesium alloy; made of an aluminum alloy as well as copper, steel and cadmium measuring 2.54 X 2.54 cm and 0.08 cm thick in 100 ml of the oil mixture to be tested heated to 121 ° for 168 hours, with about 51 air being passed through per hour. Here, the metal strips in the Order magnesium, aluminum, copper, steel composed according to a square and the Cadmium strips arranged in the diagonal. This entire arrangement is hung into the test mixture, and after the end of the experiment, the individual metal strips are washed and dried and the corrosion loss determined by weighing. Experiment B differs only in that the metal strips heated to 121 ° for 71 hours while 11 air per hour through 20 ml the test mixture is passed. Trial A is detailed in * Military Specification MIL-0-5606 described. The following Tables I and II show those with various lubricant blends Test results obtained, with the addition of the corrosive effect of the same on the various metals also the acid number at the end of the experiment as well as that due to oxidation under the stated experimental conditions caused percentage increase in viscosity are given.

It can be seen that mixtures which do not contain any additives within the meaning of the present invention cause severe signs of corrosion in most cases, especially with copper, in many cases, however, also with cadmium. In addition, the tables show that an addition of either the Metal salt of the condensation product or the epoxy compound alone the corrosion of one or several of the metals tested are not sufficiently prevented. One by the numbers in the tables The additional effect shown consists in the reduction of the acid number and in the percentage increase the viscosity, which by oxidation under the conditions of the two above-mentioned test methods caused.

Further mixtures according to the invention are listed below:

lubricant 24 at
25th game
26th 27 Caproic acid-i, 3, 5-heptanetriol-
ester Φ Trioctyl aconitate ....... 98 98 Mixed polymer of ethylene
glycol and trimethylene glycol 98 Butadiene monoxide I. i, 2-epoxy-3-aminobutane I. Pinene oxide I. i, 2-epoxy-5-ethoxypentane .... I. Mg salt of a formaldehyde
Hexylphenol condensation
product I. Ba salt of an acetaldehyde
Dibutylphenol condensation
product I. I. Zn salt of a crotonaldehyde
2-ethylhexylphenol condensate
station product I.

Table I.

lubricant

example

1 7 18

12th

14 15

Dinonyl-ß, ß'-thiodipropiönat ι, 5-pentanediol-bis-dibutyl-

phosphate

Plexol 2oi ^a )

Plexol 244 ³ )

Silicic acid (2-ethylhexyl) -

ester ■.

Phenylphosphonic dihexyl

ester ..._

Hexylphosphonic dihexyl

ester

Glycidyl phenyl ether

Octylformol ¹ )

2, e-ditert.-butyl - ^ - methyl-

phenol

Acryloid HF 8125

Attempt a

Cu

Mg

Fe

CD

Al

Acid number

% Increase in viscosity
at 37.7 °

(Percent by weight of the individual components of the total mixture)

98.0 100.0 97.5 100.0 98.0 100.0 98.0 100.0 98.0 92.0 91.0 IOOjO 91.2
2.0 1.0
1.0 5.8 2.0
o, 5 1.0
1.0 1.0
1.0 1.0
1.0 1.0
7, o 1.0
6.0 1.0
1.0

(Weight change in mg / cm ^{a of} the metal surface)

9.94 ο

1.16 0.91 5, not specified

1.72 23.4 0.15 4.0 ° 0.02 1.98 O 6.56 0.12 7.0 0.03 53.3 0.09 0.16 13.5 0.05 25.57 0.01 82.8 O 50.12 O - 0.02 +0.03 0 - O O O 0.03 0.05 O 0.16 0.04 - 0.02 +0.10 0 0.04 0.46 0.06 4.64 0.04 12.2 O 7.28 0.16 5.0 0.02 0.24 0.02 O O O 0.03 O, O2 O 0.24 0.08 - 0.04 +0.02 0 0.05 10.3 1.09 32.2 0.04 39.6 0.01 7.24 0.14 - - 10.25 o, 44 5.0 27.0- 21, © - 14.5 5.0 35,000 4.0 70.0 5.0 - - ii, 5. 8.0

97.5 2.0 0.5

¹ J Ca salt of the condensation product from formaldehyde and octylphenol.

² ) di- (2-ethylhexyl) sebacate.

³ ) Di-isooctyl adipate.

Table II

lubricant

16 18th

example
I 2

23

Phenylphosphonic acid diisooctyl ester, 5-pentanediol bis-dibutyl phosphate

Glycidyl phenyl ether

Octylformol; ....

Attempt B

Cu

Mg

Fe

Cd ·,

Al

Acid number

% Increase in viscosity at 37.7 ° (percent by weight of the individual components of the total mixture)

98.0 98.0 98, O 98.0 98, O 98.0 Ι, Ο 2, O 2.0 Ι, Ο Ι, Ο 2, O 2, O Ι, Ο

(Weight change in mg / cm ^{a of} the metal surface)

20.24

27.44 ο

5.12

. 0.04

49.4 116.0

16.56 + 0.16 0.08 0.04 2.72 0.52 23.3 ■ + 0.40 0 0 0.28 0.16 O + 0.08 0 .0.04 0.04 0.08 0.36 + 0.08 0 0 0.28 0.08 O 0 0 Ό 0.08 0 43.1 1.04 1.49 1.24 3.52 0.65 118.0 1.0 9, ° 7, o 10.0 3, o

3.44

0.48

0.04

0.04

1.38

1.0

Claims (1)

PATENT CLAIMS: i. Lubricants based on esters of phosphoric acids, silicic acids, carboxylic acids or of compounds with polymeric linear chains, characterized by a content an epoxy compound and a metal salt of a condensation product known as a lubricant additive from an aldehyde and a phenol or a thiophenol in amounts of preferably 0.1 to 6 percent by weight and especially from 0.5 to 2.5 percent by weight of each component, based on the total mixture. 2. Lubricant according to claim 1, characterized in that that the epoxy compound is a glycidyl alkyl ether or a glycidyl aryl ether, in particular contains a glycidyl phenyl ether. Referred publications:
U.S. Patents Nos. 2,562,144, 2,573,568,
580 274. 534 6.56