US1939995A - Lubricating oil - Google Patents

Description

Patented Dec. 19, 1933 UNITED STATES PATENT OFFICE LUBRICATING OIL ware No Drawing. Application July 25, 1932 Serial No. 624,643

2 Claims. (CL 87-9) Our invention relates to improved lubricating oils and specifically comprises such products as new compositions of matter.

Due to advances in the art of manufacturing mechanical devices the manufacturer of lubricants is required to produce high quality lubricants with film strengths much higher than is obtained in straight high quality hydrocarbon lubricants. In addition to this, lubricants of high oiliness character are also required and it is known that the best quality straight hydrocarbon lubricants are deficient in this property of oiliness or unctuosity, as well as being of low film strength. The product of this invention is a high quality lubricant with greatly increased film strength and greatly improved oiliness.

Mechanical devices are being designed and fabricated with friction surfaces under high pressuites and moving at slow speeds. A lubricant in this service must have high oiliness characteristics because it is the most important property of the lubricant under the conditions of boundary or thin film lubrication. The viscosity of the lubricant plays little or no part under these conditions because the lubricant body has been.

squeezed from between the frictional surfaces leaving only a very thin film of lubricant.

With only a thin film of lubricant between the frictional surfaces which are operating at high pressure and slow speeds, the thin film must have a very high film strength and not break down, which would cause irreparable damage to the frictional surfaces. I

We have found that the product of our invention has a strong afiinity for the metal of the frictional surfaces and will penetratethe metal, forming a'film of lubricant on the metal which will not drain away. As a matter of fact it is very diificult to remove without act-rally grinding away or removing a thin layer of the metal itself. Thislayer of lubricant is always on the frictional surfaces ready to act as an efficient lubricant and is of extreme value during the engine starting period when lubricant for one cause or another has not reached or been pumped to the frictional surfaces.

The product of our invention has suflicient of the oiliness property to overcome the increased friction resulting from the dilution of straight hydrocarbon lubricants by unburned motor fuels resulting from the operation of nearly all of the machines using liquid hydrocarbon fuels.

Those skilled in the art of lubricant manufacture or machine lubrication will appreciate the great importance of these improvements.

In outline our invention consists of the halogenation of wax and fatty acids, and the like, and the subsequent condensation of these halogenated products with each other by alkaline I condensation reagents. The product of such so condensation is then added to a hydrocarbon lubricant in small quantities to improve the film strength and oiliness of the lubricant and to obtain the other advantages of this invention.

To prove the efficiency of our invention we 5 rupture the film. of the lubricant blended with the product of the above condensation and determine the pressure required to obtain the rupture. This pressure is then determined for the straight high quality hydrocarbon lubricant used for blending with the product of the condensation. By a comparison of the two results the great improvement is at once evident. The equipment employed for this test is known as the testing machine which was developed and has been described by the Timken Roller Bearing Company. This is the best equipment known to us for making these tests and is similar in op eraition to the operation of commercial machines.

A further test to prove the efficiency is by determining the coefficient of friction of the blended and unblended lubricant for comparison. The machine used for this test is the Herschel friction testing machine which was developed by Dr. W. H. Herschel of the United States Bureau of Standards.

An example of our invention will serve to clarify the general conception but should not be construed as a limitation to our invention.

Example A fi l-126 F. melting point hydrocarbon wax was chlorinated until the chlorinated product has a melting point of 60 F. This chlorination was done by direct addition and substitution. In another container a batch of commercial stearic acid was chlorinated by direct substitution until the chlorinated product had a cold test of 13 F. Equal quantities of these two chlorinated products were mixed and treated. with sodium ethoxide in an alcohol solution. Sufficient sodium ethoxide is added to cause the removal of part of the halogen from the chlorinated war: and from the chlorinated stearic acid in addition to that required to form the sodium soap of the fatty acids present. When the chlorine atoms are removed from the two molecules they can combine with each other or be saturated with the free 002215. It is thus possible to substitute a number of fatty acid molecules on a saturated hydrocarbon molecule. Other, type molecules are also present.

After condensation is complete, the alcohol is removed by distillation and the sodium atom forming the soap with the carboxyl group is replaced by treating with dilute hydrochloric acid. The product is then water washed to remove traces of hydrochloric acid. A solvent such as a light naphtha .or other solvents may be used to facilitate washing. After washing, the solvent is removed by distillation. The product may be used after the removal of the solvent or may be further purified by low pressure distillation.

The product of the above condensation was added to a high quality 350 pale oil. The straight pale oil had a Herschel coefficient of friction of 0.135 thus indicating its high quality. Using 1% of the product of the above condensation in a sample of this oil, the Herschel coefficient of friction was reduced to 0.083 or about 39%.

A sample of high quality steam refined stock showed a Timken film strength of 18.2# weights at a speed of 390 ft./min., which is equivalent to a pressure of 10,500 pounds per square inch. To other samples of this same steam refined stock /2% and 1 of the above condensation product was added, with the following results:

Seizure point 390 ft./min. on steam refined stock 18# weight, approximately 10,500 pounds per sq. in. pressure.

Seizure point 390 ft./min. on of condensation product plus steam refined stock 23.0# weight, approximately 13,500 pounds per square inch.

Seizure point 390 ft./min. on l of condensation product plus steam refined stock 40.5# weight, approximately 23,000 pounds per square inch.

By increasing the amount of condensation product the film strength increases. 1 more than doubles the film strength of the original high quality lubricant.

In the example cited hydrocarbon wax was'used' The fatty acids obtained by commercial saponification of animal or vegetable oils are suitable. The process of saponification does not influence the process. Naturally occurring organic acids or synthetic organic acids may be used. Naphthenic acids may be employed. The fatty oils, esters, etc. may be employed instead of the acid, since they will be saponified by the alkaline conde sins agent, freeing the halogenated fatty acid, which will then enter into the reaction.

High molecular Any of the well known halogenation processes may be used. We do not intend to cover any particular method of halogenation. Any of the halogens or mixtures of the halogens may be used. The so called wax may be halogenated with one halogen and the fatty acid, fatty oil, ester, etc. with another.

Any of the alkaline condensing agents such as sodium hydroxide, sodamide, alcoholic potash, sodium methoxide and the like may be used. In some cases the reacting mixture must be warmed to obtain the required reaction. Those familiar with the art of condensing organic molecules are thoroughly familiar with the slight modifications necessary to obtain the desired result. Solvents may be used for the reacting components. By varying the amount of condensing agent and/or the amount of halogenation of the wax and/or acid, it is possible to obtain considerable variation in the halogen content of the finished condensation product.

The carboxyl radical must be freed of the sodium atom which is done by inorganic acids.

The reaction mixture may be purified by organic solvents, heating, distilling, water washing, etc. prior to use.

We assume that the halogenated wax and halogenated fatty acid combine in part to form a new molecule. Two or more halogenated acid molecules may be attached to one wax molecule, or two or more halogenated wax molecules may be combined with one halogenated acid molecule. The final product, no doubt, contains unchanged acid, unchanged wax, unchanged halogenated acid and wax, as well as other molecules formed in the reaction with the reacting components. The final product is not a pure chemical compound but a mixture of compounds. Our invention is not limited to our conception of the chemical composition of the product or of the reactions which take place.

In the example given 1 /2% of the condensation product was the greatest quantity used but larger quantities may be used and may be as high as 15% or more. It will be obvious that the amount used depends upon the degree of halogenation, raw materials, degree of condensation and conditions of use of the finished lubricant and other variable factors.

The product of this invention may be used in any type of lubricant or blended lubricant with very highly satisfactory results.

Having thus describedour invention,.what we claim is:

1. A lubricating oil comprising in combination a hydrocarbon oil and a small quantity of a halogenated wax-halogenated organic acid condensation product.

2. A lubricating oil. comprising in combination a hydrocarbon oil and a small quantity of a chlorinated wax-chlorinated fatty acid condensation product.

BERT H. LINCOLN. ALFRED HENRIKSEN.