DE1059599B - Synthetic lubricants - Google Patents

Description

Synthetic Lubricants The invention relates to use mixed formals as synthetic lubricants of superior lubricating properties at high and low temperatures, which practically no deposits in the Left behind combustion chamber of piston engines.

When trying to find better specialty lubricating oils with special properties to win, new types of synthetic substances with lubricating properties were developed, the good viscosities at low and high temperatures compared to mineral oils exhibit.

This makes them particularly suitable for the lubrication of machines, which have to work within a wide temperature range, such as jet engines, Aircraft turbines, piston engines and the like are mineral oils in view of their too low viscosity indices unsuitable for these purposes.

It has been found that formals of organic oxy compounds in which two molecules, each of which has one or more free alcoholic hydroxyl groups contains, linked by a methylene group (-CH2-), as synthetic Lubricating oils of excellent stability and excellent properties at high and low temperatures can be used. This series of connections has the Composition AOCH2 OB, Type I where A and B are organic radicals and the total number of the carbon atoms in the molecule is at least 20.

This series of compounds includes formals with the composition AOCH2O (CnH2nO) XCH2OR, type II in which A is an organic radical with 1 to 60 C atoms, preferably the remainder of a monohydric alcohol, and (CnH2n0) xCH2OR an organic residue with 1 to 60 carbon atoms means in which R is the radical of an oxy acid ester, a mercapto acid ester or of the condensation product of an alkylene oxide with an oxy acid ester, x and n integers, namely x at least 1, preferably 2 or 3, and n at least 2, preferably 4.

The subject of patent 961 483 is the use of mixed formals organic compounds containing at least one alcoholic hydroxyl group of the general structural formula A-0 [CH2-0 (CnH2nO) yxCH2-O-B, in which A and B organic radicals with 1 to 60 carbon atoms, x and it are whole numbers equal to or greater are than 2, y is an integer equal to or greater than 1 and the total number of C atoms in the molecule is 20 to 130, as a synthetic lubricant or component synthetic Table lubricant with a pour point below 1.7 ° C, a flash point above 150 ° C and a kinematic viscosity of 2 to 60 cSt at 98.9 ° C.

The part [CH2 in square brackets appears in this formula - O (CnH2nO) y] x at least twice, because x is equal to or greater than 2.

Compounds according to the formula of the previous patent must therefore be grouped of two or more CnH2nO groups bounded by a CH2 O group from one another are separated, or two or more consecutive CnH2nO groups, which are separated by a C H2 O group from a similar grouping of consecutive CnH2 »O groups are separated. Formal forms of this type are expressly included in the subject matter of the present invention except. This type of connection does not fall under the constitution of either Formula of claim 2 of the present patent; the only group that repeats here is the CnH2nCO group; the successive CnH2n ° groups become not separated by intermediate groups.

For the preparation of the formals used according to the invention, those in the present If the patent is not protected, one can assume that chloromethyl ethers are used.

Chloromethyl ethers for the preparation of the formals are especially useful is advantageous if the formula contains two = contain these residues should, e.g. B. R O C H2 O R '. The mormethyl ether of alcohol, which is one of these residues is produced as follows: ROH + CH2O-HCl + ROCH2C] + H2O.

This is then treated with the alcohol corresponding to the rest of the rest : ROCHgCl + HÖR'- ROCHgOR '+ HC1.

The compound thus obtained can be referred to as a mixed normal will. If this type of formaldehyde is made from the alcohols ROH and R'OH as well as formaldehyde is produced, a mixture of the following three compounds is obtained: ROCH20R, ROCH20R ', R'OCH20R '.

For example, a mixture of Cm oxo alcohol yields Lnd Cx3 oxo alcohol in reaction with formaldehyde a product whose boiling range is equimolar Genetically expect the simple formal Cio H210 OCH2OC10H21 C13 H27 0 C H2 0 C13 H27 u was. The presence of the mixed formal Clo H210 C H2 ° C13 H27 is suspected but could not be proven.

The following types of reactions are preferred: 1. Preparation of a simple one Type I formals by reacting 1 mole of an alcohol with 1 mole of the chloromethylate an alcohol.

2. Preparation of a Type II formal by reacting 2 moles of one Chloromethyl ether of an alcohol with 1 mole of a glycol; or the reaction of 2 moles of an alcohol with 1 mole of a bis-chloromethyl ether of a glycol.

3. Formal preparation by treating polyvalent compounds, such as Cellulose, starch, glycerine, sorbitol, polyvinyl alcohols and the like with chloromethyl ether of alcohols.

4. Reaction of polyether alcohols, e.g. B. the condensation products of alcohols with alkylene oxides, such as ethylene oxide or propylene oxide, with chloromethyl ether of alcohols or with bis-chloromethyl ethers of glycols.

5. Reaction of esters of oxy acids, e.g. B. Esters of lactic acid, Glycolic acid, oxybutyric acid, oxyvaleric acid, oxycaproic acid, oxystearic acid and the like. Like., with chloromethyl ethers of alcohols or with bis-chloromethyl ethers of glycols.

6. Treatment of the abovementioned oxyacid esters with alkylene oxides, such as Ethylene or propylene oxide, and reaction of the condensate formed with the chloromethyl ethers of alcohols or the bis-chloromethyl ethers of glycols.

7. Reaction of 2 moles of an alcohol or a glycol monoether with 1 mole of a dichloromethyl ether.

8. Condensation of an alcohol with 2 or more molecules of trioxymethylene with the formation of alkyl polyoxymethylene chloromethyl ethers, -R (0 CHCl, which very are reactive and easily with the esters of oxyacids or with other hydroxyl links, z. B. oxymono-and-polycarboxylic acids, alcohols, glycols and the like., Condense.

9. The replacement of oxygen by sulfur in the above Formulas and the formation of the corresponding thioformals. For the present proceedings thioacids, thioglycols, etc. can be used.

Example 1 1 mole of tridecyloxo alcohol is mixed with 1/2 mole of bis-chloromethylethylene glycol condensed. The condensation product is obtained almost quantitatively and has the following Properties: Viscosity at 37.8 ° C ................ 18.04 cSt 89, 36 SUS at 98, 9 ° C ................ 3, 85 cSt 38, 92 SUS viscosity index 121 pour point, ° C 59 Flash point, ° C .......... 242 This product therefore meets the requirements which are to be put to a high quality lubricant.

Example 2 Preparation of C13H27OCH2OC13.5H28 hydrogen chloride gas is in the course of 51/2 hours in a stirred mixture of 800 g Cl3-oxo alcohol (4 moles) and 141.6 g of paraformaldehyde (91% CH2O) (4 moles). After 16 hours The one consisting of 1015 g of C13 oxochloromethyl ether, C13H27OCH2Cl, is left to stand upper layer separated from the aqueous hydrogen chloride layer (108 cm3; 126 G). To 254 g (1 mol) of this chloromethyl ether, which forms the upper layer, is added one 200 g of hexane. The mixture is heated to 80 ° C. over the course of one hour sets in this time 207.5 g (1 mol) of a Cl0-Cl8 alcohol mixture through A mixture of primary Clo Cle alcohols obtained from coconut oil hydrogenation about 3% C10, 46% C12, 24% C14, 10% C16 and 17% C18 alcohol, too. The development of hydrogen chloride shows the formation of the mixed formal. The reaction mixture is then refluxed at 100 ° C for 4 hours, with hydrogen chloride gas developed. After washing out the reaction product with 2 portions of 100 cm3 each Na2CO3 solution and 2 portions of 100 cm3 water each, it is filtered and stripped off. During the stripping process, some hydrogen chloride is still formed, which indicates that that part of the chlorine compound remained inactive in the presence of sodium carbonate and becomes reactive at higher temperatures. That above 177 ° C at 0, 2 mm boiling product (boiler temperature 204 ° C) has the following properties: Table I Cl3-alcohol mixture-formal (alcohol mixture-)) Kinematic viscosity at 98.9 ° C ................ 3, 32 cSt 37, 28 SUS at 37, 8 ° C ................ 12, 73 cSt 68, 60 SUS at -17.8 ° C .............. viscous-solid viscosity index ............ 151 Flow point, ° C ............ 7 Flash point, ° C ............. 213 Ignition point, ° C ........... 227 Combustion test, mg coal ................... 2, 4 blackening 1, 5 Example 3 Preparation of Tridecyl Glycolate For the preparation of tridecyl glycolate is first a mixture of 70% glycolic acid, cig-oxo alcohol, Toluene and a small amount of toluenesulfonic acid monohydrate refluxed until no more water collects in the separator. The mixture is then cooled, poured into water, extracted with ether and fractionated. The one at 105 to 110 ° C boiling fraction, which has the acid number 0 and the saponification number 208 mg KOH / g has, is further treated with cig oxochloromethyl ether; this ether is in the Manufactured in a way that converted Cl3-oxo alcohol, trioxymethylene and hydrogen chloride until hydrogen chloride was drained from the condenser. The product is cooled treated with water to decompose chloromethyl ether that has remained unchanged, extracted with ether, dried and finally distilled under 1 mm pressure.

A product which passes over at 173 to 210 ° C. is obtained.

Example 4 Preparation of tridecyl tridecoxymethoxy lactate Cl3H27OCH20CHCOOC13H27 CH3 The same process used to make the tridecyl glycolate described above Found application is also used for the production of the intermediate product tridecyl lactate. The reactants are used in the same proportion, and also the method of isolation and purification is the same. The oxyester is sinking 1 mm print at 125 to 130 ° C above. Its acid number is 0 and its saponification number 213 mg KOH / g. This is very close to the theoretical saponification number of 206 mg KOH / g.

To prepare the tridecoxymethoxy derivative, the same procedure is followed applied as described above for the preparation of the corresponding glycolate is. The condensate passes under 1.5 mm pressure at 180 to 200 ° C.

Example 5 Preparation of methyl lauroxymethyl polypropylene ether glycolate A mixture of methyl glycolate and boron trifluoride-ether complex is gradually mixed with propylene oxide with stirring and cooling. The mixture is then stirred for a further 2 hours and then poured into water and extracted with ether. The extract is washed with water and then with sodium carbonate solution, dried and evaporated. The residue is topped up to a flask temperature of 200 ° C. under 1 mm pressure.

The residue has an acid number of 0 and a saponification number of 68 mg KOH / g. This corresponds to a molecular weight of 826, which means that the molecules contain an average of 12.7 propylene oxide units. The product thus obtained, methyl polypropylene ether glycolate, is condensed with lauryl chloromethyl ether in the same way as is described in the preceding examples for the corresponding reactions. The end product is topped up to a metal bath temperature of 230 ° C under 1 mm pressure. The residue that has not passed over consists of a weakly colored, viscous oil.

Example 6 Preparation of tridecyl tridecoxymethylthiopropionate C13H27OCH2SCH2CH2COOC13H27 First the C13-oxoester of ß-thiopropionic acid is prepared in the usual way, adding main C13 - oxo alcohol in the presence of toluenesulfonic acid as a catalyst and Allowing toluene to act as an entrainer on p-thiopropionic acid. The ester is through Purified distillation under 1 mm pressure. Most of the product goes with 141 to 142 ° C above. This proportion is in the same with C13 oxochloromethyl ether Condensed way, as in the previous examples for the corresponding Condensation of the chlorine ether with esters of oxy acid is described. To the final Cleaning, the condensate is distilled under 1 mm pressure. The one at 173 to 183 ° C passing fraction, which contains most of the condensate, is then tested for their suitability as a lubricant.

Example 7 Preparation of n-butyltridecoxymethylthiopropionate C13H2OCH2SCH2COOC4Hg The n-butyl ester of ß-thiopropionic acid used as an intermediate in this experiment is in the usual manner by the action of n-butyl alcohol in the presence of a Acid produced as a catalyst and a carrier on p-mercaptopropionic acid. The finished ester, which passes under 30 mm pressure at 117 to 119 ° C, becomes almost received quantitatively.

The condensation of this ester with Oxotridecylchloromethylether is performed in the same way as in the previous experiment for the corresponding reaction is described. The end product is purified by distillation and consists of a colorless oil.

The formals are now subjected to standard ASTM lubricating oil tests. It is their viscosity at 37, 8 and 98.9 ° C and their viscosity index, furthermore their flow and flash points are determined. Also, the synthetic oils are another Subjected to test to determine incombustible content.

This test is performed as follows: A 5 g sample of the test oil is placed in a weighed beaker and burned. After the combustion has ended the beaker is cooled to room temperature, the residue by determination the weight difference is determined and indicated as blackening and oil carbon. The deposited carbon is then carefully removed mechanically from the beaker and the blackening now remaining as residue is determined by weight.

The key figures of those produced according to the preceding examples Oils are given in Table II. For comparison, a mineral oil is also comparable Viscosity listed.

A number of glycol bisformals are made in accordance with the invention. Here, 2 moles of the chloromethyl ether of the selected alcohol with 1 mole of the Glycol reacted. The chloromethyl ether is produced in all cases according to the process which is used in detail for the preparation of the Cl3-oxo alcohol chloromethyl ether is given in Example 3. Examples 8 to 15 below relate to Manufacture of glycol-to-formal.

Example 8 2 mol of the chloromethyl ether of Cg-oxo alcohol are with 1 mol of tetramethylene glycol reacted for about 24 hours at about 120 to 145 ° C. the end the reaction mixture becomes that formed during the reaction by a stream of nitrogen Removed hydrogen chloride. The product obtained is now down to a liquid temperature stripped from 200C C at 1 mm Hg.

Example 9 2 moles of Cx oxo alcohol chloromethyl ether are mixed with 1 mole of tetraethylene glycol reacted at about 120 to 145 ° C.

The reaction mixture is sparged with nitrogen to remove the the reaction to remove liberated hydrogen chloride. The product obtained is washed with an alkaline solution, then with water and over anhydrous Dried potassium carbonate. The washed and dried material is then filtered and under a pressure of 2 mm Hg to a liquid temperature of 200 ° C stripped.

Example 10 Following the procedure described in Example 9 will be Brought 2 moles of C8-oxo alcohol chloromethyl ether with 1 mole of tripropylene glycol in reaction.

Example 11 Following the procedure described in Example 9 will be 2 moles of chloromethyl ether of Clo-oxo alcohol and 1 mole of tetramethylene glycol together brought into reaction.

Example 12 According to Example 9, 2 moles of chloromethyl ether of 2l0-oxo alcohol are used brought into friction with 1 mole of tetraethylene glycol.

Example 13 According to Example 9, 2 moles of Cl0-oxoalcohol chloromethyl ether are used with 1 mole of tripropylene glycol in reaction; brought.

Example 14 Using the procedure described in Example 9, verden 4 moles of Cl, -oxo alcohol chloromethyl ether brought into reaction with 1 mole of pentaerythritol.

Example 15 2 moles of Clo-oxo alcohol chloromethyl ether are about! 4th Hours at about 135 ° C. with 1 mole of nonanediol; it sets. During the reaction blast nitrogen is passed through the mixture to remove the hydrogen chloride released during the reaction to abort. The product will then twice with water and twice with 10% aqueous solution Sodium hydroxide solution, then washed out again 2 times with water and finally over anhydrous Dried potassium carbonate. The washed and dried product is then wildly filtered and now down to a liquid temperature of 205 ° C at a pressure of 1.5 mm Hg stripped.

The glycol bis-formals obtained according to Examples 8 to 15 are used Subject to ASTM tests for lubricants. The results are in the table III stated.

For the separation of the manufactured products it may be desirable to apply a selective solvent.

When glycols are brought into reaction with chloromethyl ethers, can in some cases a mixture of mono- and bis-formals is produced; if you z. B.

0.5 mol of the chloromethyl ether of Ci3-oxo alcohol with 0.5 mol of polyethylene glycol 400 reacts to produce the monoform, some glycol remains unchanged, and the remainder is converted to the monoformal and the bisformal of the Cl3 oxo alcohol.

This mixture is broken down by extracting it 4 times with The diformal is removed every 500 cm3 of hexane.

The monoformal is extracted from the unchanged glycol separated with diethyl ether, in which the polyglycol is insoluble. The product makes up 320 g and is thus divided into 138 g diformal, 128 g monoformal and 20 g of unchanged glycol decomposed.

This working method is also applicable to the cases in which a Partial formalization of a hydrocarbon-insoluble alcohol, e.g. B. n-butyl-0- (C H2 C H2 O) 15 H, takes place. The formal is drawn out and the one that has remained unchanged Recirculated alcohol to the formalization zone. The hydrocarbon layer distilled wildly to obtain the fully formalized product.

Formal can also be called »bright stocks <r (highly viscous lubricating oils) serve to mix with other natural or synthetic lubricants. Very valuable products are obtained, for example, by mixing the products according to the invention Formal with the esters of dibasic acids, e.g. B. Esters of adipin, sebacin, Glutaric and succinic acid. The formals can also use synthetic lubricants be mixed on the basis of complex esters, such as. B. the alcohol dibasic Acid-glycol-dibasic acid-alcohol complexes and the like as "bright stocks" they can be mixed with lower viscosity formals to achieve the desired viscosity to achieve. On the other hand, the formals can be thickened to high viscosity, by adding more viscous substances or thickeners, such as viscosity index improvers, to them or other accessories. The formals to be used according to the invention can also be used known detergents, oxidation inhibitors, etc. add.

It has been found that lubricants obtained by thickening the invention Formals are obtained, or mixtures of the same with other synthetic or natural lubricants mixed with fat-forming soaps have valuable properties, especially lubrication at extreme temperatures, have given them a far industrial level Secure the area of application. One can use the alkali or alkaline earth soaps of high molecular weight Use fatty acids and manufacture the fats using methods known in the art.

For example, soaps such as oleates, stearates, ricinoleates, and the soaps of acids of vegetable or animal origin, e.g. B. of fish oleic acids, can be used with Na, K, Li, Ca, Ba, Sr.

Table II Physical properties of mixed formals of oxy and polyether acid esters Ver Viscous combustion Visco ASTM sitit visco flame test By- Product 37.8 ° C at sititspunkt Ö A + 98.9 ° C index on-off black 1) sw SUS SUS ° C ° C mg I mg Mineral oil 195 47, 1 111-37 210 46, 0 38, 0 3 C13H27OCH2OCH2COOC13H2. 113, 7 40, 5 102-54 216 3, 8 3, 3 CH 4 109, 3 40, 0 100-54 191 4, 7 1, 4 CH3 5 n-C12H25OCH2O CH - CH2O12,7CH2COOCH3 ... 359, 0 71, 7 140 +13 227 3, 4 3, 4 6 C13H27OCH2SCH2CH2COOC13H27 172, 6 45, 6 116-51 229-- 7 114, 6 41, 3 107-54 185 4, 4 2, 2 1) OA-t reputation. === Oil carbon precipitation + blackening.

Table III. Suitability of Bisformals as Synthetic Lubricants Flow Flame Viscosity in SSU At- name of the ether name of the glycos point at at speil ° C ° C 98.9 ° C 37.8 ° C 8 C8-oxochloromethyl-ethyl tetramethylene glycol ... -59 204 40.2 76.2 9 Same. Tetraethylene glycol ... -59 210 41.1 80.4 10 the same tripropylene glycol ... -59 210 43.9 85, 1 11 Clo-oxo-chloromethyl-ether tetramethylene glycol ..- 59 218 40, 1 86, 2 12 also tetraethylene glycol .... -59 221 45.3 98, 4 13 degl. Tripropylene glycol ........ -59 210 44.7 88.8 14 the same. Pentaerythritol .....- 51 224 47, 1 174 15 also 221 51, 3 173, 1 PATENT CLAIMS: 1. Use of mixed formals with an ASTM pour point below about 1.7 ° C, a flash point above about 149 ° C and a kinematic viscosity at 98.9 ° C between 2 and 60 cSt, the total molecule of which is about 20 to 130 Contains carbon atoms, of the composition AOCH20B, in which A and B are organic radicals with 1 to 60 carbon atoms, preferably those of monohydric, especially branched-chain alcohols - to the exclusion of formals of the composition A - O [CH2 - O (CnH2nO) y] xCH2 - O -B in which A and B are organic radicals with 1 to 60 carbon atoms, x and n are integers equal to or greater than 2, y is an integer equal to or greater than 1 and the total number of C- Atoms in the molecule is 20 to 130 - as a synthetic lubricant or a component of synthetic lubricants.

Claims (1)

2. Use of mixed formals according to claim 1 of the composition AOCH20 (CnH2nO) ssCH20R, where A is an organic radical with 1 to 60 carbon atoms, preferably the remainder of a monohydric alcohol, and (CnH2nO) xCH2OR an organic residue with 1 to 60 C atoms denotes, in which R is the radical of an oxy acid ester, a mercapto acid ester or of the condensation product of an alkylene oxide with an oxy acid ester, x and n integers, namely x at least 1, preferably 2 or 3, and n at least 2, preferably 4, are synthetic as a synthetic lubricant or ingredient Lubricant. Publications considered: German Patent No. 917488; Excerpts from German patent applications, Vol. 6, 396. Older patents considered: German Patent No. 961 483.