DE1468587C - Synthetic lubricants - Google Patents

Description

The invention relates to synthetic lubricants for aircraft engines.

As is known to those skilled in the art, modern aircraft are designed to operate at high altitudes. Of course, this means that more stringent requirements are placed on the lubricating oils used in the engines will. For example, the lubricant must have a relatively low pour point and a . have a high viscosity index. It must also be sensitive to chemical inhibitors and stabilizers being.

An additional problem arises with engines for jet engines. Such engines are for you Operation at high temperatures intended. Therefore, the lubricant must operate at temperatures in the range of 260 ° C and more be effective and remain stable.

It has been suggested that synthetic lubricants be used in special applications, for example in synthetic lubricants Aircraft, through the polymerization of α-monoolefins by thermal or catalytic means in Presence of catalysts such as di- (tert.) Alkyl peroxide and Friedel-Crafts catalysts including Boron trifluoride and aluminum chloride. These lubricants have low pour points. And high viscosity indices. However, they are insufficient in the high temperature lubrication condition stable and, in some cases, have insufficient sensitivity to additives. If you hydrogenated them to increase the stability by saturating the olefinic double bonds, it has been found that this greatly increases the pour point and that the lubricant is nevertheless at are unstable at high temperatures.

It has now been found that new highly effective saturated synthetic lubricants are made from polymerized Olefin can be produced in a simple and economical way:

1. By removing the dimer fraction of a polymerized α-Monoolefins before hydrogenation becomes a synthetic lubricant of low level Pour point, good inhibitor sensitivity and high viscosity index generated.

2. This synthetic lubricant can be used for lubrication by simple heat treatment can be made stable at high temperatures.

The general purpose of the invention is to provide improved new synthetic lubricants from hydrogenated polymerized olefin to develop the increased inhibitor sensitivity, high viscosity index (From left) and have a low pour point. Another purpose of the invention is under development new synthetic hydrogenated polymerized olefin lubricants exhibiting thermal stability, to see. A particular purpose of the invention is to provide hydrogenated synthetic lubricants, which are made from polymerized α-monoolefins and have low pour points as well as high Have viscosity indices. Another specific purpose of the invention is to provide new hydrogenated ones synthetic lubricants made from polymerized α-monoolefins and treated in this way that they are thermally stable. The advantages of the invention will become apparent to those skilled in the art from the following detailed description.

The process for making the new synthetic lubricants involves the distillation of a synthetic lubricant made from polymerized normal «monoolefin, creating a fraction which contains dimers, and a residue fraction which is essentially free of dimers is formed becomes, and the complete saturation of the residue fraction by hydrogenation.

The invention also provides a new thermally stable synthetic lubricant. The process for the preparation of the new thermally stable lubricant comprises the distillation of a synthetic lubricant from polymerized normal α-monoolefin, whereby a fraction containing dimer and a residual fraction which is substantially free of dimer is obtained, as well as the complete saturation of the Residue fraction by hydrogenation and the heating of the so saturated residue fraction at a temperature between 316 and 37 Γ C. The period of time is between about one and about 10 hours, preferably it is at 343 ⁰ C for 3 hours.

A thermally stable synthetic lubricant according to another embodiment is by the distillation of a synthetic lubricant from polymerized normal «monoolefin (whereby a fraction which contains dimers and a residue fraction which is essentially free .von Dimer is obtained) by heating the residue fraction to a temperature between about 316 and 371 ° C (the time is between about one and about 10 hours) and through the full Saturation of this residue fraction heated in this way is obtained by hydrogenation.

The term "high viscosity index" used in the specification refers to viscosity indices of about 125 and above. The expression "Synthetic polymerized normal" monoolefin lubricants "refers to synthetic ones Lubricants obtained by polymerizing normal α-monoolefins containing 6 to 12 carbon atoms either thermally or catalytically in the presence of a di (tert.) alkyl peroxide or a Friedel-Crafts catalyst including boron trifluoride and aluminum chloride produced under mild conditions will. The term excludes polymers that are in the presence of other peroxides, such as diacyl peroxides were prepared, the polymers containing structural elements of the peroxide catalyst. It is it has been found that polymers prepared in the presence of a di- (tert.) alkyl peroxide, no structural elements of the peroxide catalyst contain. The latter polymers are therefore almost equivalent to thermally polymerized olefins. When using Friedel-Crafts catalysts, the polymerization conditions must be proportionate be mild.

To produce the synthetic lubricants according to the invention, the high viscosity index, Having low pour points and good inhibitor sensitivity is the choice of normal α-monoolefin monomer important. The best and most preferred monomer is 1-decene. For polymerization des 1-decene is used the relatively pure monomer or an olefin or Hydrocarbon mixture rich in i-decene. However, it has also been found that mixtures normal alpha monoolefins containing between about 6 and 12 carbon atoms can be used can when the mean value of the chain length of the olefin is about 10 carbon atoms. So results

for example a mixture of equal parts of 1-hexene, 1-octene, 1-decene and 1-dodecene is satisfactory Lubricants according to the invention.

The thermally polymerized olefins useful for this purpose are disclosed in U.S. Patent 2,500,166 described. The polymerization will generally take place at temperatures comprised between about 260 and 399 ° C are performed for a period between about 20 hours and 1 hour. Preferably the polymerization is carried out at temperatures comprised between about 316 and 371 ° C.

In U.S. Patent 2,500,166 the ole- ' Finnish reaction components are normal α-monoolefins, which have between 6 and 12 carbon atoms each Own molecule. Suitable olefins are, for example, 1-hexene, 1-octene, 1-nonene, 1-decene and 1-dodecene. The olefinic reaction component can consist of essentially pure normal α-monoolefins, Mixtures of olefins and / or paraffins which contain substantial amounts of normal α-monoolefins or mixtures of normal α-monoolefins containing between 6 and 12 carbon atoms own, exist.

The polymeric oils made by polymerizing normal α-monoolefins in the presence of a di (tertiary) alkyl peroxide catalyst are described in U.S. Pat. No. 2,937,129. The olefinic reaction component consists of a normal α-monoolefin or mixtures thereof, preferably those which contain between 7 and 12 carbon atoms per molecule. Examples are: 1-heptene, 1-octene, 1-decene and 1-dodecene. The catalyst is a di (tert.) Alkyl peroxide, preferably a lower di (tert.) Alkyl peroxide. A readily available and particularly preferred catalyst is di (tert.) Butyl peroxide. The amount of peroxide catalyst used is between about 0.01 and 0.3 moles per mole of normal α-monoolefin reactant. The working temperature is the activation temperature of the Peroxydkatalysators and lies between about 100 and about 200 ⁰ C. The reaction time. is generally between about 1 hour and about 6 hours.

Polymerized normal α-monoolefin oils can easily prepared in the presence of Friedel-Crafts catalysts under relatively mild conditions will. As is known to those skilled in the art, severe working conditions cause particularly with some of the preferred Friedel-Crafts catalysts, undesired side reactions, isomerization, resin formation etc. It should also be noted that all Friedel-Crafts catalysts are not entirely equivalent are in the nature of the oils produced. The selection of the catalyst and the type of reaction conditions for the production of polymeric lubricants depends very much on the desired viscosity:

The polymerization of 1-decene (or its equivalent) with an AlCl ₃ catalyst at temperatures below about 70 ° C gives lubricating oils with a kinematic viscosity of 25 to 45 cSt at 99 ° C. In general, these oils are made by gradually mixing the olefin with 1 to 3 weight percent (based on total olefin feed) AlCl ₃ over a period of 2 to 6 hours. A preferred procedure involves the additional addition of the olefin to a slurry of the catalyst in an inert hydrocarbon such as n-heptane.

The polymerization of 1-decene (or its equivalent) in the presence of AlCl ₃ at temperatures of 100 to 200 ° C gives oils which have a kinematic viscosity of about 12 cSt, measured at 99 ° C. An apparatus suitable for execution operation is quickly add AlCl ₃ and the olefin to suddenly raise the temperature to 150 ⁰ C or higher rise. Under these conditions the polymerization easily proceeds to such an extent that

ίο that most of the olefin has been consumed, before the reaction mixture reaches the boiling point of decene.

In the case of BF ₃ catalyzed polymerization, the use of pressure or a catalyst accelerator or promoter is necessary to produce high quality synthetic lubricants. Suitable accelerators or promoters are a BF ₃ -decanol complex, decanol, acetic acid and an acetic acid-BFj complex. In general, the polymerization is carried out at temperatures below 60 ^° C. for a total reaction time of about 2 to 4 hours. When the BF ₃ polymerization is carried out under pressure, a reaction time of 2 to 4 hours is used. The pressure, measured in terms of the BF ₃ pressure, can be between about 0.7 and 35.9 atmospheres or higher. In both cases of the BF _3- catalyzed polymerization of 1-decene or its equivalent, polymeric oils are produced which have kinematic viscosities of about 3 to 6 cSt at 99.degree.

As stated above, the inhibitor sensitivity of the synthetic lubricant is made polymerized n-a-monoolefin due to saturation of the synthetic lubricant by hydrogenation elevated. However, such treatment unfavorably increases the pour point of the lubricant.

example 1

A mixture of 3100 g (22.14 mol) 1-decene and 160 g (1.10 mol) di (tert.) Butyl peroxide was in a reaction vessel heated to a temperature of 150 ° C for 5 hours. The reaction product thus obtained was first at atmospheric pressure and then distilled at 60 mm absolute pressure to remove unreacted 1-decene. The one left behind polymeric oil product had the properties given in Table I.

B ei s ρ ie I 2

The polymeric oil product of Example 1 was hydrogenated to saturate the olefinic double bonds. The hydrogenation was carried out in accordance with customary procedures using a shaking bomb with a nickel-on-diatomaceous earth catalyst (20 g per 100 g of oil). The initial hydrogen pressure was 105.5 atmospheres. The temperature was kept at 149 ^° C. for 3 hours, followed by slow cooling.

example 1 Example 2 KV at 99 ° C, cSt
KV at 38 ⁰ C, cSt
VI 9.47
56.92
139
<-54
700 9.12
52.92
141
+ 1.7
680 Pour point, ⁰ C
Molecular weight, calculated

It can be seen from the data in Table I that the hydrogenation of the polymeric oil is not substantial Has an effect on the viscosity properties of the oil. On the other hand, the pour point became around 55.6 ° C elevated.

Example 3

Parts of the synthetic lubricant given in Examples 1 and 2 have been known Mixed oxidation inhibitors. Each mixture was subjected to the laboratory oxidation test (B-IOA). The associated values of the mixtures and the test results are listed in Table II.

In the laboratory oxidation test (B-IOA), a 25 cm sample of the test oil is polished in a 200 χ 25 mm test tube together with 100 cm ^{2 of 4.8 cm 2 of} iron wire that has been sandblasted

Copper wire, 5.5 cm ² polished aluminum wire and 1.06 cm ² polished lead surface were introduced. The tube is held at 163 ° C in an aluminum block bath. Dry air is passed through the test oil for 24 hours at a rate of 101 per hour. After completion of the test period the increase in the neutralization number (NZ) (ASTM D-974), the percent increase in viscosity, measured at 38 ⁰ C, the amount of the optionally occurred slurry, and the weight loss of the lead specimen is recorded in milligrams.

Table II

· ■ Additives None NZ-
A ntAiI oil from example 1 lead - NZ
portion oil from example 2 mud lead Inhibitor 162.1% / AlHCIl % Visc. loss none % Visc. loss Acryloid794.1% 9.9 modification mud (mg) 8.7 modification none (mg) OD 561, 1%; Quinazarin, 7.2 KV at 38 ° C 21 8.9 0.49 KV at 38 ° C sense 0.1% (techn.) 1000 none 130 570 0.4 OD 561, 1%; Quinazarin, 2.9 436 none 254 0.00 6.8 none 0.1% (recryst.) 44.5 206 0.2 OD 561, 1% agerite Hi 0.23 164 none 0.00 5.5 none Par, .0.5% Acryloid 794, 0.2 Tricosyl P.A.N. 1% 1.3 8.7 none 0.12 5.1 none Tricosyl P.A.N. 10% 0.4 6.9 17.5 none - 7.9 - 4.1 1.1 a lot - 232 none - 70.6 136 none 34.0

The additives used in the blends and listed in Table II were commercially available antioxidants and stabilizers. "Inhibitor 162" is a mixture of mono- and di-lorol (C ₁₂ ) esters of orthophosphoric acid. "Acryloid 794" is a polymethacrylate VI improver. "OD 561" is cadmium diamyl dithiocarbamate. »Agerite Hi Par« is a mixture of phenyl- / ϊ-naphthylamine, isopropoxy-diphenylamine and diphenyl-p-phenylenediamine. "Tricosyl PAN" is tricosylphenyl-a-naphthylamine. The listed approaches of the additives are characteristic of lubricating oil approaches.

From the values in Table II it can be seen that the hydrogenated synthetic lubricant is larger Has sensitivity to inhibitors. As stated above, however, this advantage is through affects the unfavorable increase in the pour point. In one embodiment of the invention The advantages of a hydrogenated synthetic lubricant and low pour point are through simple fractionation of the synthetic lubricant has been obtained.

Surprisingly and contrary to the usual expectation, it was found that the dimer fraction polymerized normal α-monoolefin synthetic lubricant to the high Flow point caused. Hence, it becomes a hydrogenated synthetic lubricant of lower pour point obtained by using a fraction of the synthetic lubricant from polymerized normal α-monoolefin, which contains the dimer, removed by distillation. The residue thus obtained is then hydrogenated to saturate the olefinic double bonds. The dimer cut can Polymerization stage are fed back together with fresh monomer charge. Possibly The same results can be achieved if you first run the synthetic lubricant polymerized olefin hydrogenated and then removed the dimer. However, this way of working is less desirable. since the dimer is now saturated and in this case not to be fed back into the polymerization stage is available. That means if there is no use for the saturated dimer there is a loss in the process.

The following example illustrates a hydrogenation and distillation procedure when in use of 1-decene as an olefin feed.

Example 4

Using the procedure described in Example 1, 3100 g (22.14 mol) of 1-decene are polymerized, 160 g (1.10 mol) of di (tert.) Butyl peroxide catalyst being used. The polymerization was carried out at 150 ^° C. for 5 hours. Unreacted 1-decene was removed by distillation. The properties of the polymeric oil thus obtained (referred to as crude polymeric oil) are essentially those of Example 1.

This polymeric oil was subjected to distillation around a cut that is essentially made up of

^{Dimers and which boils up to 180 0} C under a pressure of 1 mm Hg, to remove. The remaining oil (referred to as "distilled polymeric oil") had the properties listed in Table III.

The distilled polymer oil was made by hydrogenation saturated in contact with a nickel catalyst. The conditions used were those same as those of Example 2.

The product (referred to as "hydrogenated distilled polymeric oil") had those listed in Table III Properties.

Table III

Distilled
polymer oil Hydrogenated,
distilled,
polymer oil KV at 99 ° C, cSt
KV at 38 ° C, cSt
V. I. 14.62
109.5
130
-48
880 14.85
114.97
128
- 37
890 Pour point, ⁰ C
Molecular weight

From the values in Table III it can be seen that the removal of the dimer fraction sets the pour point severely humiliated. It should be noted that the pour point even after hydrogenation of the topped polymer Oil was low.

As mentioned above, the dine can be removed either before or after the hydrogenation. This is illustrated by the example below.

Example 5

A thermal polymeric oil was obtained by heating 1337 g (9.55 moles) of 1-decene at a temperature of about 343 ° C for 10 hours at a maximum pressure of 7.03 atü. The product was topped to remove unreacted 1-decene, leaving a polymeric oil. This oil was then subjected to distillation at about 145 ° C under a pressure of 3 mm Hg, to remove the decendimer. The residue (referred to as "polymeric oil without dimes") had the properties listed in Table IV.

This dimer-free oil was over a nickel catalyst hydrogenated under the usual conditions described in Example 2. The resulting oil ("dimer-free, hydrogenated, polymeric oil") the properties given in Table IV.

Since the pour point was unsatisfactory, the hydrogenated polymer oil became up to a vapor temperature distilled from 230 ° C at a pressure of 1 mm Hg to remove the decene dimer. The residual oil (hydrogenated polymeric residual oil) had the properties shown in Table IV.

Table IV

KV at 99 ° QcSt ..
KV at 38 ° C, cSt ..

Polymer,
oil without
Dimers

7.11
41.71

Dimer-free,
hydrogenated,
polymer
oil ¹ )

7.39
43.50 '

Hydrogenated, polymeric residual oil

9.18
61.16

') The removal of the dimer was found to be incomplete.

Polymer
oil without
Dimers Dimers
free.
hydrogenated,
polymer
oil ¹ ) Hydrogenated,
polymer
Back
standing oil >
1 134
- 51
0.8403
(36.9.) 134
- 12.2
0.8363
(37.7) 128
- 45.6 Pour point, ° C
Specific
Weight

') The removal of the dimer was found to be incomplete.

From the values given in Table IV it can be seen that the dimer was before or after the hydrogenation step can be removed.

The above examples related to polymeric oils, which by thermal polymerization of 1-decene in the presence of di (tert.) Butyl peroxide have been prepared. Very satisfactory products is also obtained from polymers obtained by polymerizing 1-decene or its equivalents have been prepared in the presence of Friedel-Crafts catalysts.

Example 6

A reaction vessel was charged with 3000 g of a 1-decene and placed in a cooling bath. A total of 26 g of AlCl ₃ was added in small portions over a period of 95 minutes. During this period, the temperature of the reaction mixture was maintained at 20 to 36 ° C. Thereafter, the reaction mixture was filtered to remove the solid catalyst. The filtrate was rinsed with ammonia to remove dissolved aluminum compounds and filtered. The rinsing operation was repeated. The final filtrate was distilled to remove unreacted monomer and subjected to distillation up to 132 ° C at a pressure of 0.5 mm Hg to remove the dimer. The remaining polymeric oil had the properties given in Table V.

Example7

A reaction vessel was charged with 300 g of 1-decene and 3 g of AlCl ₃ was added all at once. The temperature of the reaction mixture rose from 26 to 150 ° C. within 4 minutes. A water bath was placed on the reaction vessel to remove the heat. After 40 minutes the temperature was 8O ⁰ C. The reactants were held for 1 hour at 80 ° C. The crude product was filtered to remove the solid catalyst. The filtrate was washed first with aqueous sodium hydroxide (5%) and then with water and filtered. The product was distilled to remove unreacted monomer, and the dimer was removed by distillation at a temperature up to 210 ° C under a pressure of 1 mm Hg. The remaining polymeric oil had the properties as shown in Table V.

Example 8

A reaction vessel was charged with 3000 g of 1-decene and boron trifluoride gas was introduced at 24 ° C. After 15 minutes, 90 g of an acetic acid-BF ₃ complex were added to the reaction mixture

209 628/37

puts. In the course of 5 hours, the temperature rose only to 38 ° C and then dropped to 3O ⁰ C. The hydrocarbon material in the vessel was separated and _{neutralized with 100 cc of concentrated NH 4} OH. Then the oil was washed with water and filtered. The monomers and the dimers were removed by distillation up to 200 ⁰ C at a pressure of 1 mm Hg. The remaining polymeric oil was converted into a fraction boiling at 200 to 222 ° C. at a pressure of 1 mm Hg. As is generally the case with BF ₃ catalyzed polymeric products, the trimer is as good a synthetic lubricant as the remainder of the oil product. The properties of the trimer cut and residual oil are listed in Table V.

Example 9

This example illustrates the preparation of polymeric oil from a mixture of 1-olefins having an average of 10 carbon atoms. A charge was placed in a reaction vessel containing, by weight, 25% 1-hexene, 25% 1-octene, 25% 1-decene, and 25% 1-dodecene. 1.4 percent by weight of the decanol-BF ₃ complex was added in two portions over a period of 3 hours. The reaction temperature was between 5 and 29 ° C. The product was washed and filtered. Then it was topped to remove the monomer and distilled at a pressure of 0.4 mm Hg up to 190 ^° C. to remove the dimers.

A heavy distillate (mainly trimer) was removed from the remaining oil, which boils at 190 to 224 ° C at a pressure of 0.4 mm Hg. The properties of this distillate and the residual polymer oil are listed in Table V.

Table V

6th
Residue 7th
Residue KV at 99 ° C, cSt
KV at 38 ° C, cSt
V. I. 31.85
296.8
126
-48 11.86
84.84
128
-54 Pour point, ⁰ C

example

j C. Trimeres Residue 2.77 6.40 Trimeres product 11.06 37.93 3.69 102 127 16.22 131 Residue 6.83 42.30 125

Example 10

A polymeric oil, prepared as described in Example 7, was prepared using the procedure from Example 2 hydrogenated. The related properties of the hydrogenated polymeric oil are shown in Table VI listed.

Example 11

A composition of trimeric and polymeric Residual oil as prepared in Example 8 was prepared using the procedure of Example 2 hydrogenated. The corresponding properties of the hydrogenated polymeric oil are shown in Table VI

listed. . . ,

⁶ Example 12

The combined polymeric oil of Example 9 was prepared using the procedure as described in Example 2 is hydrogenated. The corresponding properties of the hydrogenated polymeric oil are in Table VI listed.

It has been mentioned above that the synthetic lubricants produced herein are deals with new materials. These lubricants possess a variety of properties that were previously found in the common mineral lubricating oils were not found. For comparison purposes, in Table VI includes the properties of two typical mineral lubricating oils. Both oils were out Petroleum feedstocks for lubricating oil purposes by conventional solvent extraction, dewaxing and Filtration procedures u obtained, oil A originates from a paraffinic base material, oil B from a naphthenic base material.

Table VI

10 11th example Ol A oil B 10.52 4.20 12th 4.89 4.00 KV at 99 ° C, cSt 73.38 20.09 6.69 28.02 22.4 KV at 38 ° C, cSt 128 132 40.74 107 70 V. I. <-54 <-54 126 + 3.9 -29 Pour point, ⁰ C 249 235 -51 221 180 Flash point, ⁰ C 277 260 249 Fire test, ⁰ C ... 274

From the values in Table VI it can be seen that the synthetic lubricants according to the invention a variety of desirable properties including high viscosity index, low pour point and have a high flash point. These properties do not all appear in common petroleum lubricants on. Oil A has a relatively high viscosity index (although it is still less than 125) but has a high pour point, oil B on the other hand has a rather low pour point (it is still higher than -51.1 ° C) but one low viscosity index. In both cases the flash points are lower.

The hydrogenated polymeric residual oil products described above are excellent lubricants for many purposes. They also have excellent inhibitor sensitivities. However are, as mentioned above, the requirements for lubricants for high temperature lubrication of Jet propulsion engines very high. For such users

the synthetic polymeric oils described above are not sufficiently stable when fertilizing. According to Another embodiment of the invention, lubricants have been developed which, as a result of their stability as for. the high temperature mode of operation proved particularly suitable. You will go through a simple thermal treatment of the hydrogenated polymeric residual oils produced.

The thermal treatment is carried out by heating the polymeric oil to temperatures between about 316 and about 371 ° C for a period of time that is inversely between about 1 and about 10 hours is executed. Preferred conditions are a 3 hour treatment at 343 ° C. Preferred the oil is stirred under a nitrogen atmosphere during the thermal treatment. It is found been that the thermal treatment mode at any point in time between the manufacture of the finished heat stable synthetic polymeric lubricant can be run. For example produces stable lubricants according to the following sequence of stages:

A. Polymerization of 1-olefin, removal of the Dimers, hydrogenation and heat treatment, or polymerization of 1-olefin, heat treatment, Removal of the dimer and hydrogenation, or polymerization of 1-olefin, removal of the

Fire test, ⁰ C

specific weight
(Er.API)

example
13 (A) 13 (B)

Dimers, heat treatment and hydrogenation.

30th

The preparation of the polymeric oil can be completed with a hydrogenation step, even if the sequence A is applied. The thermal treatment usually causes some cracking to olefins; it is therefore desirable to mix any oils To saturate bonds that may have formed.

Example 13

293

0.8989 0.8408

(26.1)

Example 14

A trimeric decene oil made as in Example 8 was obtained by about 3 hours Heat treated to about 343 ° C. The oil treated in this way was made using the im Procedure described in Example 2 hydrogenated. The corresponding properties of the hydrogenated treated Oils are given in Table VIII.

Example 15

A residual decene polymeric oil prepared as in Example 8 was obtained in about 3 hours long heating to about 343 ° C thermally treated. The oil treated in this way was made using the Procedure described in Example 2 hydrogenated. Corresponding properties of the hydrogenated treated Oils are given in Table VIII.

Example 16

A polymeric decene oil prepared in Example 6 was obtained by heating for 3 hours thermally treated to about 343 ° C. The oil so treated was made using those described in Example 2 Hydrogenated mode of operation. Corresponding properties of the hydrogenated treated oil are in Table VIII listed.

Table VIII

40

14th example
15th 16 KV at 99 ° C, cSt
KV at 38 ° C, cSt
KV at -40 ⁰ QcSt ...
V. I. 3.60
15.93
2 092
125
-54
210
229.5 7.07
43.03
12 805
129
-54
251.5
279.5 11.75
86.48
48 177
126
-45.6
260
285 Pour point, ° C
Flame test, ° C
Fire test, ° C

A crude olefinic polymeric oil was prepared as described in Example 1 from 1-decene. It was distilled to remove the dimer. The residual oil was then used under the usual conditions (204 ° C etc.) hydrogenated. This material 45 (Oil A) had the properties given in Table VII. A different amount of polymeric decene oil was made like Oil A. It was then through Heat treated for 3 hours at about 340 ° C. There was evolution of gas, whereby the 50 Liquid was stirred. The resulting oil (Oil B) had the properties given in Table VII. This oil was obtained by distillation below. From the values in Table VIII it can be seen atmospheric conditions and in vacuo that according to the invention heat-stabilized synthetivon volatile components. 55 see oils being created. By comparing theirs

Properties with those of oil A and B (Table VI) it is apparent to the person skilled in the art that these new lubricants have a combination of properties that did not possess petroleum-based lubricating oils.

The thermal stability of lubricants used to lubricate engines for jet engines

KV at 99 ° C cSt 16.79 11.15 used at high temperatures is on

KV at 38 ° c 'cSt 1352 7514 determined in different ways. They are different

'' '65 experimental modes have been suggested. One exists

^v · } · · · · ^{12Ί li} that the oil is in the cycle of heat

Pour point, ° C - 45.6 - 20 when exposed at elevated temperatures above

Flame test, ° C 266 - a rotating disk is pumped.

Table VII

Example ·
13 (A) 13 (B)

Testing with a rotating disc

The basic test device used to determine thermal stability is in a Publication of the American Society of Mechanical Engineers in “The Oxydation of Lubricating Oils at High Temperatures «, by A. L. W i 11 i a m s and E. A. O b e r r i g h t on the occasion of the ASME-ASLE Lubrication Conference, New York, N.Y., October 20-22, 1959. The test device ίο was modified in order to obtain a measurement of the gas formation which is based on the thermal degradation of the Test oil is due.

To test the thermal instability, the air circulation system was separated from the oxygen tank. A barometer with a U-tube was installed in its place. The circulation system was filled by purging thoroughly with nitrogen. As soon as the system reached the test temperature, oil was pumped into the disc. The system was brought to atmospheric pressure and then resealed. As soon as the hot oil was pumped onto the hot disk, the pressure increase due to the decomposition gas was measured at regular intervals of 5 minutes. The room temperature was determined by ci ^ r K '^; ^ rrrn ': n £. ~ Vcr ^ tpit kept to avoid pressure changes due to changes in room temperature!

In this test, the spinning disk was rotated at 2500 revolutions per minute. The temperature the disk was held at 274 ° C. During operation, the oil was in a thin Film passed over the disc, which was exposed to the high temperature. With thermal degradation of the Oil, a pressure rise occurs in the pressure gauge system, which is due to the gases formed.

B e i s ρ i e 1 17

The oils A and B, as shown in Example 13 and in Table V were subjected to the rotating disc test. The corresponding

Results, ', expressed ;, iri mm ^ -ptgckänstieg je · Stands, sif £ d ^ waS; ^: follows5 ';,; V "."

Dl Pressure increase mm / hour oil A. 72 ' oil B ... 2

From the values of Example 17 it can be seen that extremely heat stable lubricants have been produced in accordance with this embodiment of the invention are.

Claims (3)

Patent claims: 1. Dimer-free synthetic lubricants with a pour point of up to about -45.6 ° C, a viscosity index of at least about 125, and one high flash point, characterized by that these lubricants are produced by the polymerization of normal 6 to 12 carbon atoms α-monoolefin, removal of the dimer and hydrogenation or by polymerization of normal α-monoolefin containing 6 to 12 carbon atoms, removal of the dimer, hydrogenation and heat treatment or by polymerization of normal 6 to 12 carbon atoms containing α-monoolefin, removal of the dimer, heat treatment and hydrogenation or by polymerization of normal 6 to 12 carbon atoms containing a-monoolefin, heat treatment, removal of the dimer and hydrogenation have been. 2. Lubricant according to claim 1, characterized in that it consists of 1-decene as a u-monoolefin has been made. 3. Lubricant according to claim 1, characterized in that it consists of a mixture of 25 percent by weight 1-hexene, 25 percent by weight 1-octene, 25 percent by weight 1-decene and 25 percent by weight 1-dodecene as a-monoolefin component has been made.