US2626241A - Bentonite greases - Google Patents

Description

Patented Jan. 20, 1953 UNITED QEFl C-Ei BENTONITE GREASES NoDrawing. Application December 24, 1949, Serial No. 135,036

4 Claims. 1

This invention relates to.a new and improved lubricating com-position. Particularly, theyv invention relates to a lubricating composition, which comprises. a. synthetic. oil thickened to; a. grease consistency with an. organophilic bentonite. More particularly, the, invention. relates. to a grease composition prepared: by dispersing; in a synthetic lubricating oil a complexreaction product formed by reacting a bentoniti typeclay with an aliphatic amine salt.

The complex products formed by reacting bentonitic or montmorillonitic type clays with aliphatic amine salts are known in the art. of these compounds are described in U; S; Patent 2,033,856, issued to Smith, March 10, 1936. The swelling of these complexes in organic liquids and liquid mixtures has been observed and a mechanism advancedto accountfor the salvation phenomenon in an article by John W. Jordan in the Journalof Physical Colloid; Chemistry, volume 53, umber-ai' bru rr 1 n bas s 13 -305 inus v Ithas now been found. andforms the subject.

of this. invention that these organophilic bentonites when dispersedin a synthetic lubricating oil form valuable; grease compositions; having stable properties and excellent high dropping points.

It has been found that forv the most part these organophilic bentonites, particularly those complexesformedbyreacting an aliphatic aminesalt withthe. bentonite, are dispersible in mineral lu.-

bricating oils. only withextremedifficulty. However, when a synthetic lubricatingoilwhich containsappreciable quantities of long chain alcohols are. used these ,organoph-ilic bentonites are easilyv dispersible. and a. very satisfactory rease composition results.

Although a great'number-of; the synthetic lubricating. oilsare useful, in. manufacturing. the greases of this inventicnthe preferredembcdiment contemplates. the utilization of the synthetic oilsobtained iromthe so-called OX process. This. process may. be. described as the catalytic, reaction of monoolefins with carbon monoxide and. hydrogen. At temperatures of about 300 F. to 350? F. and under pressure of about 3Q0 pounds. per, square. inch in thepresence oiaoatawstan aldehyde is formed. This aldehyde, is .then hydrogenated to. form. a. primary cohols Zmaybe. synthesizedbp this process.- For xamp e a f act on p imer-imco s ing; o 1

olefins. which-is isolated from the-polymerization product of propylene, or a migxture oi CcandiCi o oolefi s may e nbiected o he .O oi ro 5.

Somev he .resultinsialcohol .mixturewulbe; found o. have. a m j proportion of fiealcohQliap W a a number of isomers. mm: g mo e l Weight compounds are. also/ found to be?- present;

From this reaction product,v a. major proportion of which is Ca, OX0 alcohol the-- desired cuts are removed by distillation; For example; the C8 OX0. alcohols are distilled ofi. Thebottoms or residuum left after this distillation contains a large proportion, of C alcohols, higher boiling alcohols, acetals, esters. ethers and hydrocarbons. In a distillation step the C9, .Oxo alcohols along with anyiother lowboiling materials may beremoved. The residuum left. from. this second distillation step. represents. ap-proxi mately 33% to 35% of, the. residuev remaining. after the Ca OX0. alcohols, are-removed.

That proportion. of the. product. ofthe. OX0 process remaining after. the. Ca Qxo. alcohol and the C9 Oxo alcohol .cutsare. removedthat' is to say, that. portionremainingafter the product has beensubjected; tov atem-perature 0fi250 C., are hereinafter referred as to OX0 bottoms and constitute the preferred synthetic oil operable in this invention.

Although the. above description isispecifically directed toan OX0. process for the production of a major amountof. Ca Oxo. alcohol; and. the preferred embodiment offthisinvention contemplates theuseof the, bottoms fromthis, particu.- lar process, the.inventi on is not limitedvtothe. use of these. particular bottoms, The synthetic oils or the residue remaining after distillation of the mixture of productsobtained by subjecting a Wide variety of olefinsto the 0x0 processare operable. For-instance, any of .the. variousaolefins'. obtained by polymerizating mixtures. ofi propylenes and. butylenes. may be. subjected. to: the 0x0 process and the bottomsirom these;proc esses may be used. In addition, the olefins obtained fromthe hydrocarbon synthesis reactions may be converted: to Qxo alcohols and? other products and-these bottoms are operable in this invention.

The approximate composition of the residuum boiling above 250 C. is-asfollows Inspection tests on this residuum show-z Flash point over.3i50 F. Pour point 5;5.? F. S. S. U. viscosity at E 63.13;

Of the organophilic bentonitic materialsioperable in this invention. .it. .is .preferredwtos usezthe:

complexes. formed-by reacting .bentonite: with:

aliphatic amino/salt in which the aliphatic contributed portion of the amine has a carbon chain length of from to 18 carbon atoms. Either the primary aliphatic amine salt or the quaternary ammonium salt may be used. In the case of the latter salt the aliphatic groups may be either alike or different, the total number of carbon atoms, however, must be within the range of from 10 to 18 carbon atoms.

These organophilic bentonites are normally prepared by adding to a water dispersion of the bentonite the desired aliphatic amine salt. These salts are normally prepared by reacting the aliphatic amine with the desired acid. Acetic and hydrochloric acid represent the desired salt forming acids.

In general, the amounts of the organophilic bentonites and the synthetic oil used for the formulation for the greases of this invention are not critical so long as desired stable grease structure is obtained. However, for most purposes a grease formed of from 10% to 25% of the organophilic bentonite with 90% to 75% of the synthetic oil results in greases having optimum stability characteristics and outstanding structure.

As was mentioned above the formation of the grease composition involves a. dispersion of the organophilic bentonite in the synthetic oil. This dispersion is advantageously accomplished by a milling process. This milling step may be accomplished by any of the conventional milling procedures familiar to the art such as a rolling mill, colloid mill, Lancaster disperser, Manton-Gaulin homogenizer, etc., as long as suflicient shearing action is obtained to give satisfactory dispersion.

This invention will be further explained by examination of the following examples.

Emample I Penetration, unworked 300 mm./10.

Penetration, worked (60 310 mm./l0.

strokes).

Penetration, worked (1000 315 mm./10.

strokes) (fine hole worker). Dropping point 500" F.'+'. Solubility Insoluble in boiling water.

Example II 20% by weight of a complex formed by reactin a quaternary aliphatic amine salt with bentonite was dispersed in 80% of an Oxo bottoms synthetic oil in a manner similar to that described in Example I above. Inspection tests on this grease composition gave the following results:

Penetration, unworked 250 mm./10.

Penetration, worked (60 260 mm./10.

strokes).

Penetration, worked (1000 2'70 mm./10.

(1000 strokes) (fine hole worker). Dropping point 500 F.+.

Solubility .Insoluble in boiling water.

Example III 15% by weight of a complex formed by reacting bentonite with a primary aliphatic amine salt was admixed with 8%;% by weight of 0x0 bottoms. The dispersion thus formed was passed through a standard laboratory colloid mill with 76.5% by weight of an acid-treated naphthenic distillate having a viscosity at 210 F. of 55 S. U. S. The resulting grease composition was subjected to the standard ASTM tests and gave the following results:

Penetration, unworked 290 mm./ 10.

Penetration, worked (60 310 mm./10.

strokes).

Penetration, worked (1000 325 mm./l0.

strokes) (fine hole worker). Dropping point 500 F.+. Solubility Insoluble in boiling water.

To test the oxidation resistance characteristics of the grease compositions of this invention a grease similar to that of Example I was made incorporating therein 0.5% by weight of phenyl alpha naphthylamine. This grease composition was subjected to the Norma-Hoffman Bomb Oxidation Test and gave excellent results. Operating at 210 F. and pounds per square inch initial oxidation pressure drop was 5 pounds per square inch in hours.

Although in the preferred embodiment of this invention the dispersant is a synthetic oil obtained from the 0x0 process it is also within the concept of this invention to use as the dispersant other synthetic oils. Long chain esters, esters of dibasic acids for example sebacates, adipates, and the like, polymers of cracked Wax, alkylated aromatics, polyglycols, copolymers of such materials as diolefins with other saturates, and other synthetic lubricants known to the art are operable in this invention. Of particular utility among these may be mentioned a fluid copolymer of low molecular weight obtained by copolymerizing conjugated diolefins with a minor proportion of an unsaturated comonomer. The fluid copolymer preferred is a low molecular Weight butadiene-acrylonitrile product which is liquid at temperatures as low as +20 F. to 70 F. This copolymer per se and a preferred method of preparation are described in detail in copending application Serial No. 637,782, now Patent No. 2,500,983, filed December 28, 1945.

An excellent smooth adhesive grease preparation was manufactured using a copolymer of butadiene and acrylonitrile in which about 76% by weight of butadiene was copolymerized with about 25% by weight of acrylonitrile in accordance with the procedure described in the above mentioned application.

15% by weight of a quaternary aliphatic amine salt of bentonite was admixed with 85% by weight of the copolymer of butadiene and acrylonitrile by stirring in a grease kettle or other type mixer. Dispersion was thoroughly accomplished by milling on a 3-roll paint mill. The yellow adhesive grease obtained was found to be insoluble in motor gasoline and petroleum naphthas and gave an ASTM penetration of 215 mm./ unworked and a worked penetration (1000 strokes using the fine hole worker plate) of 220 mm./10. These penetration tests data show the loss of only 5 mm./l0 after Working which indicates excellent structural stability.

The grease compositions of this invention may include any of the conventional additive materials such as tackiness agents, viscosity index improvers, anti-corrosion agents, oxidation inhibitors, extreme pressure agents and the like.

In summation, this invention comprises the manufacture of a new and useful grease composition by dispersing in a synthetic oil obtained from the Oxo process an organophilic bentonite complex formed by reacting bentonite with the salt of a long chain aliphatic amine. Either the primary aliphatic amine or the quaternary aliphatic amine may be used to obtain the salt to react with the bentonite. If the quaternary amine is used the aliphatic groups may be the same or different. The preferred embodiment contemplates the use of hydrochloric or acetic acid to form the salt with the aliphatic amine.

What is claimed is:

1. A lubricating composition consisting essentially of a synthetic lubricating oil thickened to a, grease consistency with a complex formed by reacting bentonite with an aliphatic amine salt, said synthetic lubricating oil being the residue remaining after distillation at about 250 C. of the mixture of products obtained by subjecting a C7 monoolefin to the action of carbon monoxide and hydrogen in the 0x0 process.

2. A lubricating composition consisting essentially of a synthetic lubricating oil thickened to a grease consistency with about 10% to by weight of a complex formed by reacting bentonite with a hydrochloric acid salt of a primary aliphatic amine, said synthetic lubricating oil being the residue remaining after distillation at about 250 C. of the mixture of products obtained by subjecting a C1 monoolefin to the action of carbon monoxide and hydrogen in the Oxo process.

3. A lubricating composition consisting essentially of a synthetic lubricating oil thickened to a grease consistency with about 15% to 25% by weight of a complex formed by reacting bentonite with a quaternary aliphatic amine salt, said synthetic lubricating oil being the residue remaining after distillation at about 250 C. of the mixture of products obtained by subjecting a C7 monoolefin to the action of carbon monoxide and hydrogen in the 0x0 process.

4. A process for the formation of a new and useful lubricating composition which comprises milling for the desired period of time a mixture of about 10% to 25% by weight of a complex formed by reacting bentonite with an aliphatic amine salt with about 90% to by weight of a synthetic lubricating oil, said synthetic lubricating oil being the residue remaining after distillation at about 250 C. of the mixture of products obtained by subjecting a C1 monoolefin to the action of carbon monoxide and hydrogen in the Oxo process.

WILLIAM J. SPARKS. ARNOLD J. MORWAY. DAVID W. YOUNG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,033,856 Smith Mar. 10, 1936 2,248,636 Marsden July 8, 1941 2,260,625 Kistler Oct. 28, 1941 2,467,148 Morway Apr. 12, 1949 2,531,440 Jordan Nov. 28, 1950

Claims (1)

1. A LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A SYNTHETIC LUBRICATING OIL THICKENED TO A GREASE CONSISTENCY WITH A COMPLEX FORMED BY REACTING BENTONITE WITH AN ALIPHATIC AMINE SALT, SAID SYNTHETIC LUBRICATING OIL BEING THE RESIDUE REMAINING AFTER DISTILLATION AT ABOUT 250* C. OF THE MIXTURE OF PRODUCTS OBTAINED BY SUBJECTING A C7 MONOOLEFIN TO THE ACTION OF CARBON MONOXIDE AND HYDROGEN IN THE "OXO" PROCESS.