US2315063A - Addition agent for lubricating oils - Google Patents

Description

Patented M ar30,1943 Q UNITED STATES PATENT oFrrcE Eugene Lieber, Staten Island, N. Y., assignor to Standard such cyclic groups, in such No Drawing.

10 Claims.

Oil Development Company, a corporation Delaware Application June 21, 1939, Q Serial No. 280,263

This invention relates to the preparation of new compositions of matter, particularlmhigh molecular weight polyketones possessing characteristics which make them especially useful It is to be observed that in each of such chain structures is present a repeating structural unit,

frequently containing the group:

0 o as hydrocarbon oil blending agents and lubri- '5 (15 r g eating oil blends of these polyketones.

Certain monoketones containing difierent or and an end 8101191 mixed organic radicals linked through a keto group have been found to increase oiliness of ra -clubricating oils. These are oi the general formula:

rat-R wherein R is a ring compound radical, e. g., an aryl or heterocyclic group, and R isan alkyl group. preferably having 11 or more carbon atoms. Although this class of ketoneshas been proposed for use in quantities of .1 to 1% in waxy oils for depressing of pour points, a careful study of a large number of monoalkyl aryl keto'nes belonging to this class leads to the conclusion that only a small number of these ketones accomplish this result to any substantial degree, so that their main important use depends upon their oiliness imparting properties.

The present invention demonstrates that mixed polyketones are properly constituted for eifecting a marked reduction in pour points of waxcontaining lubricating oils, particularly ,wihen these compounds contain a plurality of interlinked cyiclic and aliphatic group with the Another object is to provide the new class of polyketones thus prepared, chiefly for use as ratio of alkyl to cyclic groups limited to 1:1 I

processes for preparing compounds in this class of polyketones, having superior pour depressing power and represented broadly as containing some of the following chain structures:

0 0 organic radical, e. g., phenyl, diphenyl, na'phthyl, g B I; I R g thienyl,cyclohexyl,carbazyl, ethyl phenyL'benzyL. etc. By reacting a mono ketone of this type with 0 0 a halogen, usually chlorine, or with a bi-func- Raisin-las where R represents an 'alkyl group, R" an alkylene group, and R, a cyclic group. e. g., aromatic, heterocyclic, alicyclic, or combinations of linearly arranged polyketones.

lubricating oil blending agents.

A further object is to provide lubricating compositions wherein these polyketones are blended in sumcient proportions to effect desirable improvements in pour characteristics and other qualities.

To accomplish these objects selected compounds which'are reactive or activated so that they can be properly condensed or polymerized I into preferred structural arrangements are used. A ketone is suitably constituted for condensation into a desired polyketone if it contains no more than one alkyl group joined through a keto linkage to a cyclic group and is provided with an active substitucnt forcoupling with other cyclic groups through keto linkages without increase in the proportion of the alkyl groups to the cyclic groups. Thus activation of a mono-alkyl-aryl ketone may involve the substitution of a halogen for hydrogen at the end of the alkyl group or condensation of the ketone with a diacyl halide.

More generally, mixed mono ketones to be employed as initial. materials may be represented by the general formula:

wherein, R is an alkyl radical, and R is a cyclic densed in a Friedel-Crafts reaction yields a dewas prepared as follows:

sired polyketone product. Desired products may be' obtained by condensing the monoketone with a dicarboxylic acidhalide having two or more carbon atoms, e. g., as in oxalyl chloride or higher dibasic compounds, in a Friedel-Crafts reaction.

Another type of initial reactant includes phenolic esters of fatty acids, e. g., phenyl stearate,

or a. rearrangement product thereof, e. g., hy-

droxy phenyl-heptadecyl ketone.

The reaction is brought about between the reactive compounds, per se, or between them and relatively less active compounds through the agency of the known Friedel-Crafts type-condensing catalysts which include the halides of aluminum, zinc, iron, boron, tin, and titanium,

ordinarily 'AlCh. Other known types of catalysts may be used. These catalysts are preferably employed in relatively large quantities, for example, in substantially mole to mole proportionswith the reactants. Since-the reaction is extremely vigorous, the reaction temperature is preferably controlled by cooling so as not to rise above 300? or 400 F. and the reaction mixture is desirably heated in the presence of a solvent under refluxing conditions. Suitable solvents are compounds substantially inert to the reactants and which boil-within the desired reaction temperature range, as for example, tetrachlorethane, a parafllnic naphtha fraction, or similar saturated and halogenated hydrocarbons. The reaction polyketone product may then be recovered purifled and concentrated by washing the extract and distilling of! more volatile'materials.

Having outlined the general purposes and mode of obtaining thedesired products, the following examples are included to illustrate in more detail how the preferred compositions are made,

used, tested, and compare with other compositions.

Example 1 A mono-wax-ketone of naphthalene 280 grams of synthetic wax-fatty acids, was converted to the acid chloride composed principally of mono carboxylic fatty acids containing'an average. of more than 14 carbon atoms per molecule and derived by oxidation of war,

Wax-C by treating with 75 grams of P01: on the water bath. The resulting wax-acid-chloride was decanted from the phosphorous acid into, a mixture of 128 grams of naphthalene and 500 cc.

t of kerosene as solvent contained in a suitable readded actor. 135 grams of MCI: was now slowly AlCla the reaction mixture was heated to 100 C. and maintained thereat for 5 hours. After cooling the reaction mixture was neutralized with a mixture of water and alcohol and diluted with a further 500 cc. of kerosene. After settling the kerosene extract was distilled with fire and steam to 600 F. to remove low boiling products. The residue comprised a grams of a light-green oil. It will be designated hereafter as mono-waxketone of naphthalene.

When 1, 2 and 5% of the mono-wax-ketone of naphthalene," was prepared-as described above, was blended in a waxy-oil, the pour point of which was +30 R, the pour point of each blend was found to be +25 F., +20 F., and +15 F., re-

spectively. l

- Example 2 The mono-wax ketone of naphthalene" was chlorinated by passing chlorine gas through the ketone maintained at 300..F. in a suitable reactionvessel. The chlorination was continued until 16 percent chlorine by weight had been absorbed.

300 grams of the "chlorinated-mono-waxketone of naphthalene" was placed in a suitable reactor equipped with stirring motor and thermometer. 500 cc. of parafiin was added to act as solvent followed by grams of activated Attapulgas clay. The agitation was started and the temperature raised gradually over 2 hours to 500 F. where it was maintained thereat for 4 hours.

Throughout this period copious volumes of hydrogen chloride was evolved, indicating vigorous polymerization. At the end of the reaction period, the H01 evolution had substantially subsided. The reaction mixture was then cooled and diluted with 1 liter of kerosene and filtered free from clay. The kerosene extract so obtained was distilled with fire and steam to 600 F. to remove low boiling products. A residue comprising 118 grams of a dark brown viscous oil was obtained as product.

When 1, 2 and 5% of the polymerizationprodnot was blended in waxy-oil, the pour point of which was +30 F., the pour point oi each blend was found to be +5 F., --10 F. and l5 FEE,

respectively.

- Example 3 Mono-heptadecyl-naphthyl ketone was prepared from the following proportions of reagents:

Stearlc acid 1 grams 350 pm. do Naphthalene do AlCl: do Solvent cc. of kerosene-.. 500

with suitable agitation. After the addition of the 75 The procedure followed was exactly the same as described under Example 1. A yield of 427.2-

grams of mono-heptadecyl-ketone was obtained; when 1, 2 and 5% of mono-heptadecyl-ketone,

prepared as described above, was blended in-a waxy-oil, the pour point of which was +30 It, the pour point of each blend was found to be +30" F.', +30 F., and 20 F., respectively.

Example 4 V Mono-heptadecyl-naphthyl ketone was chlorinated by dissolving in tetrachlorethane as solvent chlorine contents, respectively.

and bubbling chlorine gas through while maintaining a temperature of 200 F. The chlorination was continued until 10% of chlorine by weight and still dissolved in the tetrachlorethane was placed in a suitable reactor equipped with agitator and thermometer. The temperature was raised to 150 F. and maintained thereat while adding 7.5 grams of AlCla. The A161: was added over a period of 20 minutes. Very vigorous polymerization ensued as evidenced by the very large and rapid evolution of hydrogen chloride. The reaction was allowed to proceed'for 3 hours at 150 F. after the addition of the A1013. The reaction mixture was then cooled and diluted with 800 cc. of kerosene and neutralized with aqueous caustic solution and alcohol. After settling, the kerosene extract was distilled with fire and steam to 700 F. to remove .low boiling products. A residue comprising 125 grams of a deep-green viscous oil was obtained.

Example The procedure of Example 4 was repeated e xactly except that the polymerization -was carried out in the presence of naphthalene. The following proportions of reagents were used:

Chlorinated mono-heptadecyl naphthyl -ketone Cl) grams 150 Naphthalene do Tetrachlorethane as solvent 'cc, 500

AlCla "grams; 7.5

The reaction temperature was maintained initially at 125 F. (3 hrs.) and then raised to 150 F. for 2 hours. After cooling, the reaction mixture was diluted with kerosene and neutralized as described in Example 4. The kerosene extract so obtained was distilled with fire and steam to 600 F. The'residue so obtained comprised 150 grams of a deep green viscous oil.

When 1, 2 and 5% of the residual condensation product was blended in a waxy-oil, the pour point of which was +30'F., the pour point of each blend was found to be +5: F., -15 1 and --25 F., respectively.

Example 6 In general, the preferred chlorination range was found to be in the region of 10-15% chlorine by weight of the mixed ketone. This was determined as follows:

Mono-heptadecyl naphthyl ketone was chlorinated as described in Example 4 to 15 and The resultin chlorinated monoheptadecyl naphthyl ketoneswere polymerized as further described in Example 4 using the following conditions:

The yields of product averaged 75%, based on v Reference oil+1% the following table:

to remove solvent and low boiling products.

the chlorinated ketone, for the two polymerizat ons.

The comparative pour depressor potency for three polymeric products made from 10, 15, and 20% chloro-ketones respectively is presented in Pour point, F. Original oil +30 Original oil+5% polymer (10% chloroketone) Example 4 -20 Original oil+5% polymer (15% chloroketone) Example 6 ---10 Original oil+5% polymer (20% chloroketone) Example 6 0 Another important observation is that the going examples briefly illustrates the effect of the polymerization on the ketones and of the increase in the proportion of cyclic groups to long alkyl groups.

. Pour point, i='.

Reference oil -Q. +30- Reference oil+l1% mono-heptadecylnaphthyl ketone +30 polyketone of Example 4-- Reference oil+2% mono-heptadecyl naphthylketone +30 Reference oil+2% polyketone of Example 4 10 Reference oil+2% polyketone of Example 5 15 Example 7 Twenty grams of adipic acid were treated with O Q iHu dissolved in cc. of tetrachlorethane as solvent.- 38 grams of A1013 were then slowly added, while maintaining agitation in a suitable reaction vessel. After the addition of'the AlCla, the reaction mixture washeated to 225 F. and maintained thereat for 3 hours. After cooling, the reaction mass was poured into an alcohol-water mixture and extracted with 500 cc. of kerosene. The kerosene extract, after washing and settling, was distilled with fire and steam to600 F. in order A bottoms residue of 107 grams of a heavygreen 'oil was obtained as product.

High molecular weight polymers in this residprocedure.

ual condensation product have structures which may be typified by:

the sameblends using mono-stearyl-naphthylketone was obtained:

. Pour point, F. Original oil I +30 Original oil+1% mono stearyl naphthyl ketone Original oil+ 1 adipylated stearyl naphthyl ketone -l5 Example 8 The procedure of Example 7 was repeated exactly using the following reagents in the proportions indicated:

Mono-stearyl-phenyl-ketone grams 100- Phthalyl chlor do 20 Tetrachlorethane as solvent cc 150 On recovery of the product 78 grams of a heavy green oil was obtained.

The condensation product results from the reaction of the following two substances:

These polymers are accordingly formulated to have the structures represented by:

or similar chains of varying length showing a Polyketone -u Condensation Polymers ratio of less than 1 s'tearyl group to each cyclic group. 7

When 1% of this condensation product was added to a waxy-oil, the pour point otwhich was F., the pour point was found to be 0 Fr When 1% of mono stearyl-phenyl-ketone was added to the same waxy-oil a pan:- point of. +30 F. was obtained.

Example 9 The procedure of Example 7 was repeated exactly using the following reagents in the proportions indicated:

0' F. When 2% of my condensation product was added to the same-waxy-oil, a pour point of --20 F. was obtained.

When 1%-of the mono-wax-ketone of naphthalene I O -WHX I where the wax represents an alkyl radical of average 17 carbon atoms, was added to the same waxy-oil, a pour point of +25 F. was obtained.

Example 10 The procedure of Example 9 was repeated exactly using the following reagents in the proportions indicated:

Mono-wax-ketone of naphthalene grams 200 Phthalyl chloride do 20 Tetrachlorethane as solvent cc 150 A101:

Example 11 7 To 18 grams of phenyl stearate dissolved in 75 cc. of tetrachlorethane was added 18 grams of aluminum chloride. The resulting mixture was placed under a reflux condenser and heated to the boiling point of the tetrachlorethane which is substantially 300 F. Refluxing was continued Mono-wax-ketone of naphthalene grams 100 Phthalyl chloride do 20 Tetrachlorethane as solvent cc 150 AiCh -grams 30 On recovery of the product, 88 grams of a viscous green oil was obtained.

when 1% of thecondensation product was added to a waxy-oil, the pour point. of which for three hours thereafter. The reaction mixture was cooled and the catalyst hydrolyzed by the action of aqueous alcohol. Upon addition of kerosene, an oily solution separated from an aqueous and sludge layer. The oily solution was decanted and distilled with fire and steam to a temperature of about 600 F. and the desired high molecular weight polymer was recovered as a distillation residue. About 16 grams of this product was recovered, which makes substantially a quantitative yield of the ester employed..

This product is a light wax-like solid which dissolves freely ln lubricating oils but is insoluble in alcohol, acetone, and similar solvents.

When 1% of this product was added to a waxy lubricating, oil the pour point of which was 30 F.,5 the pour point of the blend was found to be F.

Example 12 18 grams of mixed phenyl esters of acids obtained by air oxidation of paraflln wax was admixed with cc. of tetrachlorethane and 8 grams of aluminum chloride. The mixture was refluxed as in Example 11 for a period of three hours and the polymer product recovered from the reaction mixture as before. When 1% of the distillation residue was added to an oil having a'30 F. pour point, the-blend was found to have a pour point of 0 F. when 5% was added to the oil, the pour point was found to be depressed to 25 F.

Inthe reaction between the aluminum chloride and the phenol ester of the long chain fatty acid,

. the acyl-group apparently not only migrates withv in the molecule but also crosses over to condense was.--l- -30-F., the pour point was found to be 7b with another phenol ester so as to form a polyketone chain polymer exhibiting a pour point depressing potency characteristic of the polyketone containing a higher proportion of aryl I than long chain alkyl groups.

In preparing the reactants for the condensation, it is tobe noted that care is taken to select compounds which form substantially linear molecules wherein cyclic groups are bridged by ketone and aliphatic groups, and wherein the proportion of alkyl groups to cyclic groups is in a ratio of 1: 1 or less.

One of the eminent advantages gained through the chain reaction formation of the linear polyketones is that it allow more uniform products of any limited degree in molecular size to be produced. The size of the ployketone molecules can be controlled in the chain reaction by the proportions of active reactants and catalyst under any set reaction conditions. This fact stands out in vention are valuable additions to the group of known pour point depressants, wax modifiers,

and lubricating oil addition agents. Their prep-v aration is practical and economical since their.

ingredients are, in general, commercially available.

.their'main use in blends with other lubricating oils such as motor lubricating oils, cable oils, greases, heavy fuels, and the like: that is, for the I most part, they are to be blended with petroleum contrast to the-miscellaneous factors which must be coped with in reacting heterogeneous types of initial materials which condense in alternative :ways rather than coupling at initially determined active points, such as provided in chloro-monoalkyl-aryl ketones and the other initial reactants indicated as useful for the present invention. In the reactions used, the purpose is to condense ap propriate monoketones with selected compounds which are relatively more reactive or to condense these monoketones per se after they are suitably activated in order to produce polyketones of the required properties and compositions. It is preferable to produce condensation polymers having molecular weights ranging from about 500 to 2000 a or higher. The reactants are carefully chosen so tract upon then being distilled with fire and steam to 600 F. or 700 F., is reduced to a distillation residue free from catalysts, low molecular weight reactants and volatile matter, and is then in condition to be utilized as a highly effective pour point depressant.

The condensation products prepared as de-v scribed in the examples are high molecular weight polyketones containing principally a plurality of drocarbon oils,- have no greater volatility than lubricating oils, and in general, have a molecular weight above 500. The crude condensation products may. in some instances, contain unreacted compounds which are not active as pour point depressants. These crude products may be used directly in lubricating oils. or the active high molecular weight polyketones components may be extracted with hydrocarbon solvents as disclosed in the examples.

. cyclic and keto groups. They are soluble in hy- The products of the present invention may be I added to lubricating oils in any desired proportion. Generally, the preferred proportion for pour point depression by the highly active polyketones will be about 1 to 2% but appreciable to more extensive effects are obtained with proportions ran ing from .2 to 5%, additions above about 1 to 2% being effective to arelatively lower degree. 1

The pour point depressants of the present in.

oils which are moreviscous and higher boiling than kerosene.

They may be employed together with other,

types of blending agents such as oxidation inhibitors, sludge dispersers, corrosion inhibitors,

etc.,'or even to supplement other pour point depressors or other oiliness agents.

The foregoing description and examples are. intended to be illustrative only.

Any modifications or variations which conform to the spirit of'this invention are intended to be included within the scope of the claims, which are not intended to be limited by any theory on mechanism by which the products are formed and perform their beneficial function, nor to any particular reactants, proportions, nor conditions.

I claim:

1. An improved'lubricant comprising a lubricating oil blended with a minor amount of a high molecular weight polyketone constituted essentiallyof at least 2 cyclic organic groups interlinked through keto groups and joined in a chain to an alkyl group through a keto linkage.

2. An improved lubricating oil of low pour point comprising a petroleum hydrocarbon lubricating oilblended with a minor amount of a polyketone having a molecular weight of at least 500 composed essentially of at least 2 cyclic organic groups linearly interlinked in a chain by keto groups and by-an aliphatic group, the chain having a terminal alkyl group.

3. An improved lubricating oil of low pour point comprisinga petroleum hydrocarbon lubricating, oil blended with a minor amount of a high molecular weight polyketone constituted principally by a chain of cyclic organic groups interconnected through ketone linkages and Joined by keto groups to terminal alkylgroups, with the number of said terminal alkyl groups to the number of said cyclic groups in a ratio no greater than about 1:1.

4. An improved lubricating oil composition of low pour point comprising a hydrocarbon lubricating oil blended with a minor proportion of a polyketone selected from the class consisting of chloro-alkyl-aryl ketone condensation polymers, alkyl-aryl-ketone diacyl-halide' condensation polymers, and alkyl oxy-aryl-ketone polymers, which contain terminal alkyl groups in a. ratio no greater than about 1:1 to the aryl groups.

5. A composition as described in claim 4, in

which the polyketone is a condensation product 9. A composition as described in claim 4, in-

which the polyketone is a polymerization product of phenyl stearate.

10. A lubricant comprising a' major propor- 10 teger ofat least 1.

tion of a lubricating oil and a. small amount of a high molecular weight polyketone having the general formula:

in which R is an aromatic group, R is an alkyl group, R" is either an alkyiene or arylene group, 'mandm' areeitherflorlandnisasmaliin- EUGENE LIEBER.