DE1039682B - Lubricating oil - Google Patents

Description

The invention relates to lubricating oils, particularly those based on mineral oils, which contain a new type of additives contain.

Recent work in the field of lubricating oils for internal combustion engines is about to develop of sludge-inhibiting oils. These should act on the combustion products. They have the property that they contain the carbonaceous breakdown products of lubricating oil or fuel Keep the lubricating oil suspended so that it doesn't show up as sludge on filters, in oil nozzles or others be able to set down important parts of the machine. Sludge inhibiting oils also reduce deposits of paint and carbon on the side walls of the piston and similar parts of the internal combustion engine.

Sludge inhibiting oils are already extraordinary in one way a large number of compositions have been proposed. In the main, however, it passed they are usually made from mineral oils refined in the usual way with lower contents of metal soaps of metals of groups I and II (including the Subgroup). For example, metal sulfonates such as calcium sulfonate, alone and in combination with other connections used. There are also metal-containing complex compounds of not always certain Composition has been proposed. These also usually had the same metals as Basis. Examples of such substances which have led to considerable success are given by Sulphurisation or phosphorus sulphurisation of organic substances and subsequent reaction with metal bases obtain.

However, the use of these metal-containing compounds or complexes had a hereditary disadvantage, which consisted in an increase in deposits in the combustion chamber due to the Combustion of the added oil could not be avoided to some extent.

The invention now relates to lubricating oils which, by adding certain compounds that do not form ash, sludge inhibiting properties have been imparted.

The lubricating oils according to the invention, preferably based on mineral oil, are characterized by that they have a small proportion, preferably less than 30%, of an oil-soluble copolymer of at least one a double bond containing anil (Schiff's base) with an unsaturated monomer or a polymer mixture prepared in the presence of a saturated anile and containing a double bond Contain monomers. These lubricating oils have sludge-inhibiting properties without the tendency to ash build-up increases.

Applicant:

Esso Research and Engineering Company, Elizabeth, N.J. (V.St.A.)

Representative: E. Maemecke, Berlin-Lichterfelde West,

and Dr. W. Kühl, Hamburg 36, Esplanade 36 a,

Patent attorneys

Claimed priority:
Great Britain 4 May 1955

The aniles used as raw materials are obtained in a known manner by condensation of aldehydes and ketones with amines. The aniles have the characteristic group 7> C = N-. Two types of anilene can be used to make the polymers of the invention. One type has only one unsaturated bond in the characteristic anil group between carbon and nitrogen, but there is no unsaturated olefin bond. The other type also has an olefin unsaturated bond. An example of the first type of anil is obtained from aniline and benzaldehyde. Examples of the second type of anil compounds are obtained from laurylamine, butylamine or aniline and crotonaldehyde or acrolein.

In general, the aniles are obtained by reacting an amine, preferably an alkylamine, the 2 may contain up to 20 carbon atoms, or an aromatic amine with a ketone or preferably obtained from an aldehyde. The aldehyde can be a saturated or unsaturated olefinic aldehyde or an aromatic aldehyde. Albeit polymers of the anile alone, insofar as they are manufactured can, have a certain value, are preferably copolymers of unsaturated aniles with other unsaturated ones Compounds that contain a single olefinic double bond, or polymers of one

«09 639/441

Double bond containing monomers used * those made in the presence of a saturated anil are. Preferred monomers are unsaturated hydrocarbons, esters, alcohols, ethers, halides and Sulphides. It is of course also possible to form polymers from several components by using an anil two or more unsaturated monomers is used.

In the case of the unsaturated monomer, the olefinic unsaturated double bond is conjugated with another double bond or it has a carbon atom which is adjacent to at least one of the unsaturated carbon atoms, a substituent group which activates the double bond, for example one with a negative I effect (Ingold). Therefore, suitable monomers are hydrocarbons such as styrene and alkylated styrene (with the olefinic double bond conjugated to the double bonds of the aromatic nucleus) and analogous compounds. Suitable esters are esters of unsaturated alcohols and unsaturated acids. Here again it is advantageous that the unsaturated bond is conjugated with the ester group or with some other active, harmless group. Therefore, preferred esters have the formula: R ₃ -CH = CH-COOR ₄ . Of course, acids which can be esterified after the polymerization can preferably be used. The same applies to alcohols, ethers, halides and sulfides. In all cases the monomers have 2 to 24 carbon atoms. Examples of suitable esters are esters of acrylic, methacrylic acid and higher homologues. Of course, unsaturated dicarboxylic acids such as fumaric and maleic acids, as well as the corresponding esters, diesters, amides, etc., can also be used. Alcohols suitable for esterifying such acids are the fatty alcohols, oxo alcohols or their crude mixtures.

Each monomer may contain substituent groups that are not hydrocarbons, but are Substituent group must neither interfere with the polymerization reaction nor the final polymer properties which are disadvantageous in the case of an oil additive in view of the intended use of the lubricating oil are. The components must be chosen so that the finished polymer is soluble in oil. The basic +5 locations for this selection are known. An interesting aspect of the invention is that by Introduction of suitable groups, especially those with a straight chain - especially those with 8 to 18 carbon atoms in at least one of the monomers - the resulting polymer to the oils to which it is added is given further advantageous properties, such as an improved viscosity index and pour point.

The polymerization or copolymerization of unsaturated compounds, as they are used for the preparation of the invention The lubricating oil additives used is used is known per se and is not intended here be placed under patent protection. There are three polymerization processes that can be used:

a) Free-radical chain polymerization, catalyzed by substances such as organic peroxides (e.g. tert-butyl hydroperoxide, Benzoyl peroxide, 1-oxy-cyclohexyl-hydroperoxide-1 etc.), d. H. Substances that deliver free radicals including redox systems.

b) Anionic polymerization, catalyzed by basic catalysts (e.g. sodium malonic ester, sodium ethylate, Sodium ethyl magnesium bromide etc.), i.e. strong (Lewis) bases.

c) Cationic polymerization, catalyzed by acidic catalysts (e.g. tin chloride, iron chloride, Sulfuric acid, etc.), i.e. strong (Lewis) acids including Friedel-Crafts catalysts.

The free-radical chain polymerization can also be initiated by UV radiation and β and rays, which is particularly advantageous if the temperature has to be kept low.

Of all of these types of polymerization that can be used, radical chain polymerization is preferred. In some cases the copolymerization is very slow, e.g. B. when benzoyl peroxide is used at 60 ° C will. A particularly advantageous catalyst is α, α-azo-di-isobutyronitrile. It is believed that the polymerization takes place at the carbon-nitrogen bond.

The invention is explained in more detail using the following example:

Representation of Benzanil

424 g of aniline and 372 g of benzaldehyde were treated with 750 ecm of toluene as a dehydrating agent for 3 hours heated under reflux, collecting 72 ecm of water became.

The resulting crystalline mass was made from benzene or toluene to a constant melting point recrystallized from 54 ° C.

Polymerization of lauryl methacrylate in the presence of benzanil

Experiment 1. 86.7 parts by weight of lauryl methacrylate were used with 12.3 parts by weight of benzanil of 1 part by weight of α, α-azo-di-isobutyronitrile as a catalyst in one with a stirrer and nitrogen discharge pipe provided vessel mixed. After a reaction time of IV2 hours at 60 ° C was a obtained thick, oily, insoluble mass.

Experiment 2. 86.3 parts by weight of lauryl methacrylate were mixed with 12.2 parts by weight of benzanil and 2.0 parts by weight Lauryl alcohol mixed as a regulator, with 0.5 part by weight of α, α-azo-di-isobutyronitrile as a catalyst was used. An oil-soluble polymer was obtained under the same reaction conditions as above educated. This was used for the specified Phoron tests.

The following data from the Phoron test show the sludge-inhibiting effect of the in the presence of Benzanil prepared according to Experiment 2 polymers, if it is in a S weight percent mixture in a refined paraffinic mineral lubricating oil SAE 30 (U.S. Essolube HD-30 basis) is used will.

volume
lOVoiger sulfuric acid
(ecm) Weight of deposits
(mg) 7th
10 0.1
0.3

The Phoron number is obtained from the following test: The Phoron number is a measure of the performance of Lubricating oils in motor vehicles, in particular diesel engines. The test is carried out by the lubricating oil with an oxygen-containing, easily polymerizable substance, such as Phoron, in the presence aqueous sulfuric acid of a certain concentration is stirred. Under these conditions form when using standardized amounts of lubricating oil and Phoron and when carrying out the test at a certain temperature between 38 and 204 ° C and for a certain period of time between 0.5 and

6 hours of deposits, the amount of which depends on the volume of the aqueous sulfuric acid. Therefore the oils with the best sludge-inhibiting effects are the ones with the least amount of deposits at a given volume of acid. In practice, it is easier to do a number of attempts with gradually increasing parts of the volume of aqueous sulfuric acid and noting the acid volume, that is required to produce 10 mg of deposits (by interpolation if necessary). This is called the Phoron number of the lubricating oil. The higher the Phoron number of the lubricating oils, the better is the sludge-inhibiting effect. It is also possible to specify the Phoronzahlert of lubricating oils related to the cleanliness of machines by using a series of machine tests oiling of known Phoron numbers is carried out.

The anil content of the charge to the polymerization reaction can be between 1 and 30 weight percent vary, with particularly advantageous products containing about 10 to 15 percent by weight anil will.

Since the polymers and copolymers are used as additives for the lubricating oils according to the invention, in particular mineral lubricating oils, are used, care must be taken when selecting the components that the Product is sufficiently soluble in the respective oil base. The amount of the lubricating oil The polymers to be added depend on the nature of the oil, the required sludge-inhibiting Effect and effectiveness of the polymer. The respective amount can easily be determined by the Phoron method or determined by other known methods. General are to be added later Concentrates Products with a polymer content of 10 to 90% are recommended. The lubricating oils themselves preferably contain less than 30 percent by weight, in particular 0.5 to 20%, of polymer.

Claims (6)

Patent claims: 1. Lubricating oil, preferably based on mineral oil, characterized in that it has a lower Proportion, preferably less than 30%, (A) an oil-soluble copolymer of an anil containing at least one double bond with a unsaturated monomers with 2 to 24 carbon atoms in the molecule, in which one double bond is conjugated with another double bond, or in which at least one the carbon atom adjacent to the unsaturated carbon atoms activates one on the double bond has acting substituents, or (b) a polymer mixture of the above prepared in the presence of a saturated anile Contains corresponding conditions, a double bond-containing monomers in solution. 2. Lubricating oil according to claim 1, characterized in that the anil is the reaction product of a Is alkylamine with a ketone or, preferably, an aldehyde. 3. Lubricating oil according to claim 1 or 2, characterized in that each of the for the production of the Polymers or the copolymer, monomers used a straight chain group of 8 has up to 18 carbon atoms. 4. Lubricating oil according to claim 1 to 3, characterized in that the monomer is an unsaturated one Ester, preferably an alkyl acrylate or methacrylate. 5. Lubricating oil according to claim 1, characterized in that that the polymer is made in the presence of benzanil. 6. Lubricating oil according to claim 1 to 5, characterized in that the anil content in the starting materials between 1 and 30 percent by weight, preferably between 10 and 15 percent by weight lies. © «09 639/441 9.58