US3364232A

US3364232A - Sulfur containing pseudoaromatic detergents

Info

Publication number: US3364232A
Application number: US518787A
Authority: US
Inventors: Donald J Anderson
Original assignee: Chevron Research and Technology Co
Current assignee: Chevron USA Inc
Priority date: 1966-01-05
Filing date: 1966-01-05
Publication date: 1968-01-16
Anticipated expiration: 1985-01-16

Description

United States Patent 3,364,232 SULFUR CONTATNING PSEUDOAROMATIC DETERGENTS Donald .1. Anderson, San Anselmo, Calif-1, assignor t0 Chevron Research Company, San Francisco, Calif., a corporation of Delaware No Drawing. Filed Jan. 5, 1966, Ser. No. 518,787 Claims. (Cl. 260-327) This invention concerns novel pseudo-aromatic sulfur containing compounds and their use as detergents in lubricating oils. More particularly, this invention concerns relatively high molecular weight hydrocarbon substituted pseudo-aromatic compounds having annular sulfur and their use as detergents in lubricating oils.

Trithiones are a peculiar type of pseudo-aromatic system in having only one double bond in a five-membered ring and the inability to introduce a second conventional double bond. Trithione compounds are readily prepared by the reaction of olefins having at least one methyl group and have been reported for a variety of uses. See, for example, U.S. Patent Nos. 2,535,705 and 2,658,900. However, for the most part, the trithiones have been of relatively low molecular weight. The most commonly reported trithiones in the patent literature have been the trithiones of isobutylene and diisobutylene.

It has now been found that trithiones having a molecular weight of at least about 500 and a hydrocarbon alkyl substituent of at least about 30 carbon atoms can be prepared and find use as detergents in lubricating oils. Generally, the trithiones will have molecular weights of less than 5,000 and usually less than 3,000.

For the most part, the trithiones of this invention will have the following formula:

wherein R and R have a total number of carbon atoms in the range of 30 to 325, at least one being aliphatic hydrocarbon and the other being hydrogen or aliphatic hydrocarbon: usually one of R and R is an aliphatic hydrocarbon group of from about 30 to 325 carbon atoms, more usually from about 50 to 125 carbon atoms and the other may be hydrogen or lower alkyl. The total molecular weight is in the range of about 500 to 5,000, more usually about 750 to 3,000.

Generally, the compositions of this invention will come within the following formula:

ss wherein R is an aliphatic hydrocarbon group of from about 30 to 325 carbon atoms, preferably from about 50 to 175 carbon atoms and particularly preferred from about 50 to 125 carbon atoms, and R is lower alkyl of from 1 to 6 carbon atoms or hydrogen, usually methyl.

The aliphatic hydrocarbon substituents may be derived from a variety of sources, may be branched chain or straight chain, and while they may include cycloaliphatic groups, for the most part they will be acyclic.

Sources of hydrocarbons having the necessary number of carbon atoms include petroleum fractions, polymers of olefins of from about 2 to 6 carbon atoms, more usually from about 2 to 5 carbon atoms, e.g., propylene, isobutene, butenes, 4-methyl-1-pentene, etc.

The preferred aliphatic hydrocarbons are those derived from olefins of from about 3 to 4 carbon atoms, i.e., propylene and isobutylene; that is, polymers which are branched chain. Of course, ethylene may be copolym- 3,364,232 Patented Jan. 16, 1968 erized with olefins of a higher number of carbon atoms to provide branched chain aliphatic hydrocarbon groups.

Illustrative compounds include S-n-alkyl trithione, 5- polypropylene trithione, 5-polyisobutylene trithione, 5- (copolymer of ethylene and isobutylene prepared by the cationic polymerization of 4-methylpentene-l) trithione, 4-methyl polyisobutylene trithione, etc.

If desired, the trithione may be oxidized with a peroxidic compound to form the S-oxy trithione. This compound is believed to have the following formula:

wherein R and R are as defined previously.

The following formula:

wherein R and R are as defined previously and X is either a pair of unshared electrons or coordinately bonded oxygen, may be considered generic to the trithione and its oxy derivative.

While the trithiones of low molecular weight are readily prepared by contacting sulfur with an olefin of the following basic structure:

or a compound which fulfills the function of an olefin in the reaction, e.g., an aliphatic ketone, it is found that with the high molecular weight polyolefins, e.g., polyisobutylene, a low molecular weight trithione must be present in order to obtain the trithiones of this invention. That is, the high molecular weight olefin, i.e., of at least 30 carbon atoms, is contacted with sulfur in the presence of approximately equimolar amounts of the high molecular weight olefin and a trithione of from about 4 to 16 carbon atoms, preferably of from about 8 to 12 carbon atoms and from about a 5 to weight percent excess of the stoichiometric amount of sulfur and the mixture heated at temperatures in excess of 175 C. and generally less than 275 C. for periods ranging from about 2 to 24 hours. By distilling off the low molecular weight materials, the desired trithione compound may be directly isolated.

The oxy derivative may then be prepared by dissolving the trithione in a suitable inert solvent, e.g., benzene, and then adding hydrogen peroxide at ambient temperatures in the presence of a hydroxylic organic solvent, e.g., methanol, acetic acid, etc.

The product formed as described above may then be used in a variety of lubricating oils as detergents.

The following examples are offered by way of illustration and not by way of limitation.

Example I Into a reaction flask in a nitrogen atmosphere was introduced g. (5 gram atoms) of sulfur and 260 g. of 4 neopentyl 5 tert.buty1 1,2 dithiol-3-thione, the mixture heated at 200 C. in a nitrogen atmosphere, and 900 g. (approximately 1 mole) of polyisobutylene added over a period of about an hour. The temperature was maintained for 12 hours, at the end of which time the temperature was raised to 210 C. and the pressure reduced to about 4-5 mm. Hg and any volatile material distilled overhead. The residue Weighed 1,028 g. Analysis: S=10.0, 10.1. An infrared spectrum of the product was consistent with the trithione.

3 Example 11 Following the procedure of Example I, 900 g. of polyisobutylene (approximately 1 mole), 160 g. of sulfur (5 gram atoms), and 260 g. of the same low molecular excellent compatibility with oils. As concentrates, the compounds of this invention Will generally range from about 20 to 80 weight percent of the total composition, more usually from about 40 to 70 weight percent.

weight trithione (approximately 1 mole) were mixed in 5 Ahmhenped h p compolmds of .thls ma nitrogen atmosphere. At the end of the heating period, ventlon m lubncatmgk 011s g fg g the temperature was raised to 250 C. and the pressure ggg f hgg gg :2; i5 s gzig g h h f to 3 The residue welghed 766 Analy' drocarbyl groups are from about 4 to 36 carbon atoms. SIS. S- 6.5.

1O (Hydrocarbyl 1s a monovalent organic radical composed Example In solely of carbon and hydrogen which may be aliphatic, alicyclic or aromatic, or combinations thereof, e.g,, Into a reactlon flask was charged 9 (approx? aralkyl.) Instead of zinc, an alkyl group or polyethylenemately 1.5 moles) of polyisobutylene trithione (approx1- Oxy group may also be used Generally, the hydrocarbyl mately 8 weight percent sulfur) and 1.5 liters of benzene groups will be alkyl or alkaryL and Stirred While 170-3 (FIPPIOXimateIY moles) The lubricating fluids which may be used with the f hydrogen Peroxide (3O Welght Perceht aqueous h compounds of this invention (hereinafter referred to as mm) was addefl Over a hh mlhutes' The oils) may be derived from natural or synthetic sources. ture was then stirred for an additional 2.5 hours, followed Oils generally have viscosities of from about to 50,000 by the addition of ml. of methanol. When t appeared 20 saybolt Universal sgconds (SUS) at Among that no reaction had occhrredir 10 of acetloc acid a natural hydrocarbonaceous oils are paraflin base, naphadded and fhitemperathre ,lhcreased to 58 Thls thenic base, asphaltic base and mixed base oils. Illus- Seemed to lhlhate the macho, the hempehature was trative synthetic oils are: hydrocarbon oils, such as polyallowed to drop to 50 C. and the reaction mixture then mars of various olefins, generally of from 2 to 8 carbon held at that temperahhewhen no further reachoh h 25 atoms, and alkylated aromatic hydrocarbons; and non- Peared to be occhmhgr the Prhdhct was f with hydrocarbon oils, such as polyalkylene oxides, aromatic water and thehrganlc Phase dned sodhhh Sulfate ethers, carboxylate esters, phosphate esters and silicon hhelhd and smpped m h The residue Weighed esters. The preferred media are the hydrocarbonaceous Proxhhately 1,300 Ahalysls: S=10hmedia, both natural and synthetic.

30 The above oils may be used individually or together, Example IV whenever miscible or made so by the use of mutual sol- (A) Into a reaction flask was introduced 260 g. (1 Vent5- mole) of polyisobutylene trithione and 370 g. (10 g. Other additives may also be included in the oils such atoms) of sulfur, and the reaction flask flushed with nitrov as pour point depressants, oiliness agents, antioxidants, gen. The mixture was then heated to 200 C. and 900 g. 39 rust inhibitors, etc. Usually, the total amount of the addi- (2 moles) of polyisobutylene added over a period of 7 tives will range from about 0.1 to 10 weight percent, more hours. Heating was continued at the same temperature usually from about 0.5 to 5 weight percent. The individual for a further 14 hours. Volatile materials were then readditives may vary from about 0.01 to 5 weight percent. moved by heating the mixture to 240 C. with a stream 49 In order to demonstrate the excellent effectiveness of of nitrogen bubbling through the mixture. The product the compounds of this invention as detergentsand disweighed 770 g. Analysis: S=12.7, 12.9; molecular persants in lubricating oils, the compounds prepared were weight (ThermoNAM-Difierential Vapor Pressure Techtested in the 1G Caterpillar Test (MIL-L45 199 condinique)':770. tions). The oil used was a Mid-Continent SAE 30 oil and (B) The above procedure was repeated using the same r 12 mm./ kg. of zinc di(alkylphenyl) phosphorodithioate amount of materials. The product weighed 806 g. (the alkyl groups were polypropylene of about 12 to 15 Analysis: S=13.1, 13.2; molecular weight (Thermocarbon atoms) was included. The test was carried out NAM)'=69l. for hours and in some instances 120 hours. The fol- As already indicated, the compounds of this invention lowing table indicates the results.

TABLE I 60 Hours 120 Hour Wt. percent Example of detergent in oil Groove 1 Land 2 Underhead 3 Groove Land Underheatl composition Deposits Deposits Deposits Deposits 5 15- 3+0 100- 5-10 7.5 87-7-3-2 440330-300 3.3 10 21- sec 05- 0-0 7. 5 5l8-00 405- 55- 30 5.6

1 Groove deposits arerated on a scale of 0 to 100, 0 being completely clean and 100 being completely filled.

2 Land depoists rated on a scale of 0 to 800, 0 being completely clean and 800 being completely bla 3 Underhcad rated on a scale of 0 to 10, 0 being completely black and 10 being completely clean. 4 The results were obtained in the absence of any zine'dithiophosphate in the oil.

find use as dispersants and detergents in lubricating oils. They are of particular value in diesel engines, demonstrating excellent results under the high temperatures at which diesel engines operate. When compounded with a lubricating oil for use in an engine, the compounds of this invention will be present in at least about 0.1 weight percent and usually not more than 20 weight percent, more usually in the range of about 2 to 15 weight percent. The detergents of this invention may be used with other detergents or by themselves. The compounds of this invention can be prepared as concentrates due to their As will be evident to those skilled in the art, various.

modifications on this invention can be made or followed, in the light of the foregoing disclosure and discussion, without departing from the spirit or scope of the dish closure or from the scope of the following claims.

5 What is claimed is: 1. A composition having a molecular weight in the range of 750 to 3,000 and of the formula:

R2C=CR1 wherein R and R are alkyl or hydrogen, at least one of R and R being alkyl.

2. A composition according to claim 1, wherein R and R have a total of from 50 to 125 carbon atoms.

3. A composition according to the formula:

of from 50 to 175 carbon atoms, at least one of R and R being alkyl.

H(ii=&-CH: with sulfur in from 5 to 100 percent excess of the stoichiometric amount of sulfur required, in the presence of a trithione of from 4 to 16 carbon atoms.

References Cited UNITED STATES PATENTS 2,653,910 9/1953 Airs et al. 260-327 JAMES A. PATTEN, Primary Examiner.

J. D. RANDOLPH, Assistant Examiner.

Claims

1. A COMPOSITION HAVING A MOLECULAR WEIGHT IN THE RANGE OF 750 TO 3,000 AND OF THE FORMULA: 3-(S=),4-R1,5-R2-2H-1,2-DITHIOLE WHEREIN R1 AND R2 ARE ALKYL OR HYDROGEN, AT LEAST ONE JOF R1 AND R2 BEING ALKYL.