US2652361A - Grease compositions - Google Patents

Description

Patented Sept. 15, 1953 GREASE COMPOSITIONS Harold A. Woods and Loren C. Bollinger, Martinez, Calif., assignors to Shell Development Company, Emeryville, Calif., a corporation of Delaware No Drawing. Application December 29, 1951, Serial No. 264,232

13 Claims.

This invention relates to special grease compositions. More particularly, it is concerned with reases resistant to the solvent action of both water and of light hydrocarbons such as gasoline.

In the lubrication of metal connections for pipe lines and flexible metallic hoses and the like, difficulties are encountered when the fuel carried by the pipe line dissolves the grease or lubricant protecting the connections. This becomes a matter of great concern, particularly in military applications and especially in greases used for the lubrication of connections for the transfer of water, lubricants and fuel between planes during flight. Two types of greases have been proposed heretofore: the more common type of grease comprises metallic soaps which act as gelling agents for lubricating oils such as petroleum oils. On the other hand, greases have been suggested to overcome the hydrocarbon sensitivity of this first type comprising soaps or inorganic gels which provide a grease structure for water-soluble fluids such as ethylene glycol or glycerin. Each of these types of greases inherently possesses certain disadvantages. Greases comprising petroleum lubricants and metallic soaps have two shortcomings in that the petroleum fractions are largely soluble in light hydrocarbon fuels and, when washed away by the latter, leave a hard soapy residue which damages felt washers and the like and causes plugging of the lines or connections. On the other hand, greases comprising water-soluble lubricants, while being resistant to the solvent action of light hydrocarbons, exhibit a tendency to be washed away by rain or, if the line is utilized for water transfer, by the water passing through the line.

It is an object of the present invention to provide greases which do not leave eitherhard or soft residues when the lubricating portion of the grease has been lost. It is another object of the present invention to provide greases which are resistant to washing away by water or by hydrocarbon lubricants or hydrocarbon fuels. It is a further object of the present invention to provide greases having a balance of solvent-sensitive properties particularly designed for the lubrication of in-flight fuel transmission mechanisms.

Now, in accordance with the present invention, it has been found that gasolineand water-resistant greases leaving substantially no residues after removal of the lubricating medium are formed by utilizing as the major liquid components a mixture of a water-soluble polyoxyalkylene fluid and a partialj ester of a polyhy dric alcohol having less than six carbon atoms and a higher fatty acid. Additionally, the gelling agent for said special mixture of lubricants comprises an inorganic colloidal gel. The chief advantages gained by the use of the compositions of this invention comprise the essentially gasolineand water-resistant character of the entire combination while, at the same time, the gelling agent tends to be powdery or is washed away to a large extent during the use in the transmission of gasoline or water, thus leaving a film of the mixture of lubricants on the pipe connections and avoiding plugging of the lines or erosion of connection parts such as felt washers and the like.

More specifically the greases comprise a mixture of two miscible fluids which provide high resistance to the solvent action of both gasoline and water, said mixture being gelled with an inorganic colloid such as silica gel. The mixture is most effective when the water soluble polyoxy- ,alkylene derivative and the partial ester are present in a weight ratio of between 2:5 to 4:5.

The partial esters The fluid components of the present gasolineresistant greases comprise two essential types. The first of these is a normally liquid partial ester of a water-soluble polyhydrio alcohol, said alcohol having from two to ten carbon atoms. and higher carboxylic acids having at least 10 carbon atoms per molecule. Optimum results, are obtained by the use of polyhydric alcohols having from two to five carbon atoms and, preferably, are glycol or glycero1 partial esters of unsaturated fatty acids, the latter having at least twelve carbon atoms per molecule.

The most eiiective types include hydrocarbon monocarboxylic acids and hydroxyhydrocarbon monocarboxylic acids. 'These comprise especially saturated orunsaturated aliphatic or cycloaliphatic acids. Monoesters are preferred to obtain the desireddegree of hydrocarbon resistance. Preferably the esters containl-3 hydroxyl radicals for each ester group, such as glycerol monoricinoleate or glycol mono(12-hydroxystearate).

More especially, excellent gasoline-resistant properties are obtained by the use of partial glycerol esters of unsaturated hydroxy fatty acids. The following are typical partial esters suitable for use in the present greases: glycerol monoricinoleate, glycol monoricinoleate, pentaerythritol monoricinoleate, glycerol diric'inoleate, monoricinoleate of diethylene glycol monoethyl ether,

glycerol oleate, 1,2,6-hexantriol mono-oleate, gly-- col palmitate, hexylene(2.-methyle2,4 pentanediollmonoricinoleate, glycerol mono(l2 hy- 3 droxystearate), glycerol-mono(9,10 dihydroxypalmitate, glycerol -mono(12 hydroxypalmitoleate) and sorbitan monopalmitate, oleate or ricinoleate.

The polyoxyallcylene fluids The third essential component of the present gasoline-resistant grease compositions comprises Water-soluble polyoxyalkylene fluids. This fluid not only should be soluble in water but also miscible with the partial esters discussed hereinbefore. Preferably they should have'a volatility comparable to a medium viscosity lubricating oil but the latter property is not as important as its solubility in water and its lack-of 'solubi-lit-ylin gasoline or other light hydrocarbons. The-prin cipal functions of these fluids comprise the improvement of resistance to washing away, "by gasoline or the like, of the partial esters and at thesarne-time-theimprovement in the low temperature' o'perating characteristics of the grease. -It ,hasbeen found-that greases comprising the esterand :gelling agent operate fairly satisfactorily only'vat room-temperature or slightly below. The-presence of the additional 'fluid,'such as that described hereinafter as awater-soluble Ucon fluid; improves-the gasoline resistance of the grease-and;moreover; enables it to be used at low-temperatures such-as occur at higher altitildes, in "the-order of 65' without becoming undulyst-iif.

-'The polymeric water 'soluble fluids are -preferably those composed to a large extent of recurring oxya'lkylene units wherein the unitcontains from two'to ten-carbon-atoms and have molecular==weights"between about-250 and 1500, preferably between350 and -l200. The best fluids for the present purpose comprise the lower-alkoxy polyi-al-kyleneox-y) 'alkanols such as the lower monoa'lkyl ethersof polyalkylene oxides and glycols. Inadditionto the ethers of polyalkylene oxides or glycols, :estersmay be employed and the polymers may be either homo-polymers or co-poly'niers of twc' or more monomeric oxides or g-lyeols. ---'A-'meng thesewill be found polymers of trimethylene =glycol-or ethylene glycol, 'co-polymers of ethylene glycol and propylene glycol, co polymers-oP-ethylene'oxide and 1,2-propyleneoxide andthe like.

. --It has been-found thatuseful and improved polyox'yallzylene products of relativelyhigh'average molecular weight which areessentially mixturesof truemonohydroxy alcohols, may be ob- "tained *by the addition to--a monohydroxy aliphatic alcohol --of--a mixture ofaalkylene oxides containingcethylene:oxide and 1,2-propylene OX- ideiina' ratiopreferably fromabout 1:1to about 3:1 ethylene oxide-to 1,2-propylene oxide. By this aoxide rratio'isimeant that I in the oxide mixture, which may be used in forming such monohydroxyaalcohol.addition products, the amount of '1;2-propylene-oxideiin the mixture is from one-third I130 ianrlequal 1 amount by weight of the ethylene'oxide present.

The'reaction which, .takes place between the alcohol and {the ethylene oxide and propylene oxide'seems to pbe-a simple .addition'wherein the alkylene oxide molecules undergo conversion to the correspondi g oxyalkylene radicals, as illus- 'trated for any given-molecule by the following w erein aoniisan aliphatic monohydroxy alco- 4 hol; y and 2 represent the mols of ethylene oxide and 1,2-propylene oxide respectively; n is both 2 and 3 in a single molecule, the total number of times that n has a value of 2 being equal to y and the total number of times that n" has a value of3being 'qdafto z; aridkr+ l is" the total number of such oxyalkylene groups, being equal to yd- These-polymers are preferably mono-ethers of polyoxyalkylene glycols with monohydric ali- -phaticalcohols haiiing from one to six carbon atoms and-preferably from two to five. A typical example of'jthis series comprises the mixture of butoxy polytheteric ethyleneoxy-l,2-propylene- *oxy) -alkanols'wherein the alkanol is ethanol or 2 m'ethyl ethanol and heteric means random combination of ethyleneoxy and 1,2-propyleneoxy units. These have average molecular weights of between 250 and 1500 in which the ethylene oxide and l-zl propylene-oxide are combined therein" asethyleneo-xy and LZ-prOpylen'eoxy"'groupsin a ratio of one part by weight of l',2--propyleneoxy --for each -three parts by weight of ethyleneoxy, the mono-ethers of said mixture containing in a suigle molecule -boththe ethyleneoxy and 1,2 -propy-leneoxy-groups.

The fluids which have been found to be particularly "suitable havevisoosities"between about 50 and 2,000 SUS'atQDO F. They usually havevisoosi'ty'indices whichwary-from about to about 150. The-pour p'oints ofthelower viscosity members, which arepreferr'ed,' are between about '90" and 40 Th'eir flash points FQopenzrcup) are between about" 250 and-450 F. 'l'Ihey have fire points (open cup 1 between about '275" and 550 The preferred substances and mixtures thereof are those which have acviscosity between about EiO- and 250 -SUSat .F.

The gelling agents useful in the -present compositions comprise two main types, namely, those having zamerphjous structure, such '31:; silica, and agents prepared- ;from Eoriginally crystalline materials; such as.-clays. ,Inorganic amorphous colloids useful'f-fo-rj this-particular purpose should have an averageaparticle size diameter which is usually a bout 100;;mill-imicrons or less. Dependentsupon the process'by which the gel particles are -prepared,;the'1atter may have-a considerable variation in: surface area. heregels, for example, which"are suitablefor use in the-present compositions, have surface areas of approximately 300-400 sgua-remete rsgpergram. On the other hand, colloids aprepa-red by solvent transfer methods havesurface-areas ranging from about 300 to about l gfiiitlesquare meters per gram. Coarser particles-may he .utilized,;such-as those prepared-by burning-organic silicates and the like, to providegfinely divided j ash residues of silicaoor ot er amorphous gel having particle sizes ranging from abouth to 100 millimicrons in diameter and surface-areas of about 100 to- 200 a square metersper gram. f Flt-he simple amorphous colloidal, materials include especially oxides such as silica, magnesia, alumina, lime, barium oxide,

strontium oxide, and :th elikewater-stable metal-.

r e a ese.ssee ipan am 1 '5 tween about 3% and about 20% by weight of the gel. Other alkaline earth metals may be used in place of magnesium such as calcium, strontium, barium and beryllium. The gels may comprise a mixture of oxides or hydroxides or, alternatively, may be prepared so as to obtain a gel comprising a mixture of silicates and oxides or the like.

In addition to the amorphous gels, such as those described above, organometallic materials may be prepared by reaction of onium compounds with high base exchange naturally occurring substances such as clays and other naturally occurring zeolites. While it is necessary in the case of greases comprising petroleum lubricating oils to form such onium clays by the use of oleophilic onium compounds, in the present instance this requirement is no longer necessary. Suitable onium clays may therefore be prepared by the use of onium compounds having as little as four carbon atoms in a single onium compound substituent. It is preferred, however, that higher molecular weight materials be employed such as dimethyl dioctadecyl ammonium chloride. Onium clays of the oleophilic type have been described in U. S. Patent 2,531,440. The preferred species for use in these compositions comprises Hectorite which is a magnesium bentonite. However, such bentonites as Wyoming bentonite also may be utilized. The clays useful for the preparation of suitable onium clays should have relatively high base exchange capacities in the order of at least about 25 milliequivalents per 100 grams of clay.

The gelling materials of this invention expressed in terms of inorganic constituents exclusively, may be present in amounts varying between 5% and 25% by weight of the entire grease com osition. Preferably they are present in amounts from about 7.5% to 15% thereof.

The greases The greases of the present invention comprise the three essential ingredients in the following proportions:

Gelling agent: 525% by weight Water-soluble polyoxyalkylene fluid: 25-50% by weight Partial ester: 30-60% by weight When various proportions of these ingredients ester constitutes from 35 to 55% by weight of the grease.

The oxidation and corrosion characteristics of these compositions are improved to an outstanding extent by the inclusion of a combination of an aromatic amine and a higher fatty acid salt of a substituted oxazoline having the genera". configuration:

wherein R1 and R2 are hydrogen, alkyl, hydroxyalkyl, arylor acyl-oxyalkyl radicals and R3 and R4 are either hydrogen or alkyl substituents. Typical members of this group will be found in U. S. Patent 2,402,791. Additives which may be employed include especially those having at least six carbon atoms and preferably twelve or more carbon atoms- They may be saturated or unsaturated acids and, furthermore, may contain hydroxy groups resulting in a hydroxy fatty acid. Typical species meeting these requirements include capric acid, lauric acid, myristic acid, oleic acid, stearic acid, 12-hydroxy oleic acid, 12-hydroxy stearic acid and mixtures of acids from natural glycerides such as fish oil fatty acids, cocoanut oil fatty acids, and acids from animal fats and oils. Typical oxazolines which may be utilized in salt formation with the above acids include the following:

- 4 methyloxazo- 2 hendecyl l hydroxymethyl 4 ethyl oxazoline i i heptyl 4. (hydroxymethyDoxazoline heptyl L4 bis(hydroxymethyl) oxazoline octyloxazoline hendecyl 4,4 bis(hydroxymethyl)oxazoline 2 hendecyloxazoline 2 hendecyl 4,4 -.dimethyloxazoline, and the like. x

Suitable salts of the above class include the oleic acid salt of 2-heptyl-4-hydroxymethyl-4- ethyloxazoline; the '12-hydroxy stearic acid salt of 2-ethyl-4hydroXymethyl-4-methyloxazoline and the stearic acidsalt of Z-decyl-lA-dimethyl oxazoline. i

The aromatic amines which may be combined with these oxazoline salts include, particularly,

polycyclic amines of whichthe preferred species is phenyl-alpha-naphthylamine. It is preferred that the group contain at least one phenyl radical and that, in addition thereto, another hydrocarbon group or substituted hydrocarbon EONMM group be directly attached to the nitrogen atom,

include ,phenyl-beta-naph- Typical species thylamine, diphenylamine, phenylstearylamine, N,N'-tetramethyl-pp-diamino diphenyl methane, and the like.

Inorganic colloids, especiallyof the amorphous type, are sensitive? to the presence of water. Hence, greases containing them. tend to disintegrate if water isincorporated in the grease in amounts greater than about 1% by weight thereof. Hence, in one. aspect of the present invention these compositions comprise greases not only suitable for the describedpurposes of solvent resistance but inherently containing water resistance as well. This is due to the large proportion of partial ester-present in the composi tions. Glycerolmonoricinoleate and analogous esters act as waterproofing agents for the silica or other amorphous gel thereby preventingexgelled with silicafialwayspossess."

treme water sensitivitmwhich petroleum grease in enhancing this inherent water-resistancev of the composition, other hydrophobic surfaceactive agents may be incorporated; These, are preferably employed in an amount sufficient to provide a monomolecular layer of the hydrophobic surfactant on the surface of at least 75% of the gel; Expressed on a weight' basis this will ordinarily comprise atleast about 25% by weight of inorganic gel and-usually between about 40% and 100% by weight thereof.

The hydrophobic surfactants useful in promoting the water resistance of these compositions comprise cationic, anionic or non-ionic materials and'include especially high molecular weight amines, higher fatty acids and high molecular weight hydroxy containing organic substances. The most suitable class of. surfactant comprises nitrogenous materials such as octadecylamine, or more preferably, 'hydroxy derivatives of aliphatic amido" amines. Preferred materials are availableascommercial products ordinarily utilized as adhesion agents in asphalt compositions since it hasbeen found that they serve for the improvement of the subject greases as'well.

A particularly effective variety of cationic surfactant comprises :the condensation products of an epihalohydrin with ammonia (or a low molecular weight amine'), said product being in partial amide form with. higher fatty acids. More specifically, a preferred water-proofing agent comprisestherpartial fatty acid amide of the condensation product of epichlorohy'drin and ammonia. This product is understood to bee mixture of derivatives, the'monom-er of'which is 2-hydroxy-1,3-diamino propane; The latter constitutes approximately 1035% by weight of the condensation product while the balance of the product comprises dimers;trimers and higher polymers of this monomer. The entire condensation product is preferably in the form of an amido amine wherein between about onethird and two-thirds of'the nitrogen atoms'are in amide form with ahigher fatty acid having. at least twelve carbon atoms. Suitable acids for this purpose include tall oil acids or oleic acid aswell as acidsde'rivedfrom animal fats and the like.

' While "the cationic surfactants are suitable for use the present compositions, other I materials; suchas'inon-metallic soaps, also may be employed; A particularlysuitable type of soap; which avoids the formation of hard; residues. found-to-be' so objectionable in" fu'el'"transfer lines, comprises soaps" of 'hydroxy'alkylamines and higher fatty'acids'.. Preferably, these fatty acids have at least twelve 'carbon atoms and optimum results'are obtained when the fatty acid has between sixteen and twenty" carbon. atoms. While satisfactory results maybe, ob'-' tained with ordinary" saturated fatty acids; "the. best solubility relationships are gained by the; use of unsaturatedfatty acids andfmGr'e'es'pe-L cially, by employing unsaturated hydrox f fatty acids; Suitable acids include the following? capric acid; undecylic acid;- lauric acid: myristic acid; stearic acid; oleic acid; 95, 1'0-, 11*, 12-, or la-hyd-roxy stearic acids;-' 10 or lfii-hydroxy" palmitic. acids-: 1*0"-'hydroxy myristic"*acid;' 5,6

" The 'above types. acids {are be re 75.

actedto form salts or soaps with alkanolamines having. less than six carbon atoms per alkanol radical and, preferably, with trialkanolamines. The most commonly available species which has been found to give satisfactory results is triethanolamine. Other species suitable for the present purpose are exemplified by the following: Monoethanolamine, diethanolamine', 1,3- diaminoisopropanol, di-n-propanolamine, triisopropanolamine and butanolamines. I

The preferred type of soap comprises the soap of a trialkanolamine with an unsaturated hydroxy fatty acid having more than twelve carbon atoms in the molecule. However, derivatives of certain natural products may be employed' as well. For example, the triethanolamine soap. of hydrogenated castor oil acids is suitable in addition to the following typical soaps (salts) Triethanolammonium ricinoleate Diethanolammonium ricinoleate Tri isopropanolammonium ricinoleate Mono-butanolammonium ricinoleate Triethanolammonium-l2 hydroxystearate Triethanolammonium-10-'hydroxymyristate Triethanolammonium ii,lil-dihydroxypalmitate Triethanolammonium-12-hydroxypalmltoleate In accordance with one phase of this inventionthe preferred compositions comprise a mixture ofallzanolamine' soaps and the inorganic gelling agent in the described mixture of lubricating fluids in such proportion as to provide substantially improved water resistance for the inoranic gel but at the same time avoiding the possibility of forming. excessive amounts of residues.

with trialkanolamine'soaps. However, the latter leave softresidues which, while not as objection-'- able as the hard residues resulting from metallic soaps, are nevertheless-to be avoided as much as possible. The presence of a mixture of the inorganic" gelling agent and the alkanolamine soaps has been found to result in residues which are rapidly eliminated from the metal surface with which the grease is originally coated. This apparently is due to thep'owdery form of the amorphous gel, which tends to provide an open structure for the alkanolamine soap thus giving it a friable character which results in its being removed by erosion. The preferred compositions" of this improved type of grease comprise 5-10% by" weight of the inorganic gelling agent; 5-15% by weight of the trialkanolamine soap; 20--50% by weight of the water-soluble polyoxyalkylene fluid and 30-60% by weight of the partial ester.

In accordance-with one phaseof this invention it has been found that the corrosion characteristicsof the present greases are improved for long storage periodswhen the combination of alkanolamine soaps and inorganic gel is employed. corrosion resistance is-a desired characteristic, that is, where the grease composition is in con tact with the metal over periods of one month or more, it is desirable to add certain materials, such. as those already specified, forthe preventionof corrosion. In the absence of trialkanol= amine soap it has been found that the corrosionresi'stant characteristics-of these greases gradu' .ally diminishes in spite of the original-addition of corrosion preventivesr However, the addition of the alkanolamine soap, in the proportions referred to hereinbefore', substantially extends the period of satisfactorycorrosion prevention.

Suitable combinations of inhibitors found to It has been found that greases suitable for fuel line lubrication comprise those gelled have especially favorable action in the basic three-component system, aswell as forfextended periods in the four component grease, comprise mixtures of petroleum sulfonates with either alkylphenoxytetraethyleneoxyethanol or alkylphenoxydiethyleneoxyethanol wherein the alkyl group contains from four to twelve carbon atoms. Another highly effective synergizing pair of rust preventives include epoxy compounds in combination with organic sulfur compounds including aliphatic disulfides, aromatic disulfides, Wax disuliides, sulfurized terpenes and sulfurized aliphatic olefins. An especially effective pair of such additives is the combination of glycidyl phenyl ether and wax disulfide in amounts varying from about 0.1% to .2.5% each by weight of the total grease composition. Also, nitrites such as sodium nitrite or dicyclohexyl amine nitrite may be used. The examples which follow illustrate typical compositions of the present invention:

Percent by weight Example I:

Silica aerogel 12 Glycerol monoricinoleate 43 50 HB 100 Ucon fluid 35 Partial amide of tall oil acids and diethylene triamine 8 Sodium petroleum sulfonate 1 Higher fatty acid ester of polyethylene glycol (mol. wt. 250) 1 Example II:

Silica aerogel 10 Glycerol mono-oleate 50 50 HB 100 Ucon fluid 1 40 Example III:

Silica aerogel 8 Triethanolammonium ricinoleate '7 Poly(propylene glycol), mol. Wt. 250 30 Pentaerythritol mono-oleate 55 Example IV:

Onium clay formed between Hectorite and dimethyl dibutyl ammonium chloride 50 HB 660 Ucon fluid 45 Glycerol diricinoleate 40 Example V:

Silica aerogel 10 Magnesia aerogel 2 Glycerol monoricinoleate 45 50 HB 250 Ucon fluid 1 40 Sodium nitrite 0.5 Sodium petroleum sulfonates 1 Octylphenoxy tetraethoxyethanol 1.5

1 50 HB Ucon fluids are water soluble monoalkyl ethers of oxyethyleneoxy-1,2-propylene copolymers sold by Carbide and Carbon Chemicals Corporation. The numeral following the designation 50 HB indicates the Saybolt U111- versal viscosity at 100 F.

This grease was subjected to a cabinet humidity test, wherein steel panels coated with grease were exposed to water saturated air at 95 F. "Substantial rusting of the panel did not occur until 216 hours of exposure. The grease was soft and plastic at -65 F. and had a penetration of 130 mm. at F.

We claim as our invention:

1. A gasoline resistant grease comprising -25% by weight of an inorganic colloidal gel, 20-50% by weight of a water-soluble polyoxyalkylene fluid and 30-60% by weight of a partial ester of a polyhydric alcohol having 2-10 carbon atoms and a higher fatty acid.

2. A gasoline-resistant grease comprising from 5-25% by weight of a colloidal silica gel having particle size diameters less than about millimicrons, 20-50% by weight of water-soluble, monohydroxypoly(heteric oxyethylene oxy-1,2 propylene) butyl monoethers having an average molecular weight of at least 500 in which the oxyethylene and oxy-l,2-propylene groups are randomly combined in a ratio from about one to three parts oxy-l,2-propylene for each three parts of oxyethyle-ne, by weight, and 30-60% by weight based on the total grease of glycerol monoricinoleate.

3. A gasoline-resistant grease comprising a geliing proportion of an amorphous inorganic gel having particle size diameters less than about 100 milliinicrons, 20-50% by Weight of a mixture of water-soluble monohydroxy poly(heteric oxyethylene, oxy-1,2-propylene) butyl monoethers having an average molecular weight of at least 900 in which oxyethylene and oxy-1,2-propylene groups are combined in a ratio of one part to three parts by Weight of oxy-1,2-propylene for each three part of ,oxyethylene, and 30-60% by weight of a partial ester of glycerol and a fatty acid having at least twelve carbon atoms.

4. A gasoline-resistant grease comprising an amorphous inorganic colloidal gel having particle size diameters smaller than about 100 millimicrons and a hydroxyalkylamino soap of an unsaturated hydroxy fatty acid having at least twelve carbon atoms per molecule and as the mixed lubricant therefor a water-soluble polyoxyalkylene fluid and a partial ester of a polyhydrio alcohol having 2-5 carbon atoms and a higher fatty acid, the ratio of poly(oxyalkylene) fluid to the partial ester being between 2:5 and 4:5, said gel and soap being present in an amount of at least about 5% by weight each, the combined amount being at least suificient to form a grease structure with said lubricant.

5. A gasoline-resistant grease comprising a gelling proportion of silica aerogel and as the liquid lubricant phase thereof from about 30% to about 60% by weight of glycerol monoricinoleate and from about 25% to about 50% by weight of a mixture of monohydroxy poly(heteric oxyethylene oxy-1,2propylene) butyl monoethers having an average molecular weight of at least 900 in which the oxyethylene and oxy-LZ-propylene groups are combined in a ratio from one part to three parts by weight of 1,2-propylene for each three parts of ethylene oxide.

6. A gasoline resistant grease comprising as the lubricating components 30-60% by weight of glycerol di-ricinoleate and 20-50% by weight of water-soluble alkoxy poly(heteric ethylene oxy- Liz-propylene oxy) alkanols and a gelling proportion of colloidal silica gel.

7. A gasoline resistant grease comprising 50% by weight of glycerol monooleate, 10% by weight of colloidal silica gel and 40% by weight of watersoluble butoxy poly(heteric ethylene oxy-1,2- propylene oxy) alkanols.

8. Gasoline-resistant grease comprising between about 5% and about 25% by weight of an inorganic colloidal gel, a water-soluble polyoxyallrylene fluid and a partial ester of a polyhydric alcohol having from 2 to 10 carbon atoms with a higher fatty acid, the proportion of polyoxyalkylene fluid varying between about 2 and about 4 parts by weight for each 5 parts by weight of said ester.

9. A grease composition according to claim 8 containing in addition thereto a hydrophobic surface-active agent in an amount at least suin- 11 cient to provide a monomolecular layer thereof on at least about 75% of the surfaces of said gel.

10. A grease composition according to claim 8 containing in addition thereto a trialkanolamine soap of a higher hydroxy fatty acid, each alkanol radical of which contains less than 6 carbon atoms, the amount of said soap being at least sufficient to provide a monomolecular layer thereof on at least 75% of the surfaces of the said gel.

11. A grease composition according to claim 3 containing in addition thereto a hydrophobic cationic surface active agent in an amount at least sufficient to provide a monomolecular layer on at least about 75% of the surfaces of said gel.

12. A composition according: to claim 11 Wherein said gel is a clay.

13. A grease composition according to claim 8 containing in addition thereto minor amounts sufiicient to stabilize the composition of an aromatic amine and a higher fatty acid salt of a substituted oxazoline having the general configuration:

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,083,132 Williams: et a1. June 8, 1,937 2,425,845 Toussaint et also--- Aug; 19, 1-947 2,554,222 Stress Y .,.V May 22, 1951 2,563,606 Kimbcrlin v Aug. 7, 1951 2,573,650 Peterson. Oct. 30, 19.51 2,584.,085v Stross, .c Jan. 29, 1952

Claims (1)

1. 8. GASOLINE-RESISTANT COMPRISING BETWEEN ABOUT 5% AND ABOUT 25% BY WEIGHT OF AN INORGANIC COLLOIDAL GEL, A WATER-SOLUBLE POLYOXYALKYLENE FLUID AND A PARTIAL ESTER OF A POLYHYDRIC ALCOHOL HAVING FROM 2 TO 10 CARBON ATOMS WITH A HIGHER FATTY ACID, THE PROPORTION OF POLYOXYALKYLENE FLUID VARYING BETWEEN ABOUT 2 AND ABOUT 4 PARTS BY WEIGHT FOR EACH 5 PARTS BY WEIGHT OF SAID ESTER.