DE1111829B - Process for the production of polymers or copolymers of esters which can be used as lubricating oil additives from unsaturated organic acids and from alcohols - Google Patents

Description

It is known that various additives can be added to the lubricants used to lubricate internal combustion engines to improve the properties, these additives in particular increasing the viscosity index or serving to lower the pour point and imparting certain detergent properties to the oil. For example, it is known from British patents 665 068 and 806 906 to lower the pour point and improve the viscosity index by adding a copolymer of vinyl acetate and a maleic acid ester or a dialkyl fumarate to the oil. According to British patent specification 725 169, an additive of the reaction product of an aliphatic amine with a vinyl compound serves the same purpose. Furthermore, according to British patents 810,647 and 838,235, ash-free detergent additives were proposed which consist of alkoxylated and phosphorus sulphurized esters of an unsaturated acid with an alcohol or of a copolymer of a fumaric acid ester, an N-vinyl-substituted cyclic amide and an unsaturated ester of a monocarboxylic acid. Finally, according to US Pat. No. 2,825,717, a process for the production of lubricating oil additives was proposed in which fumaric acid is _{esterified with a C 8 -C 18} alcohol and then polymerized further with vinyl acetate.

For these purposes, therefore, products are used which are obtained either by polymerizing firstly esters of unsaturated organic acids and aliphatic, cyclic or aromatic alcohols, these alcohols having various substituents such as alkoxy, thioalkoxy, halogen, NH ₂ -, NO ₂ -, HSO ₃ -, CN and other groups may contain or be unsubstituted; second, monoesters of dicarboxylic acids and unsubstituted or substituted cyclic or aromatic aliphatic alcohols; thirdly, amino esters of the acids and alcohols mentioned above; or by interpolymerizing the above esters with a polymerizable organic compound such as, firstly, esters of unsaturated alcohols such as vinyl esters, ζ. Β. Vinyl acetate; secondly, esters of alcohols which do not have an ether function, and in particular unsaturated fatty acids such as methacrylates, etc .; third, aromatic hydrocarbons with ethylene side chains, such as styrene; fourth, unsaturated nitriles, ζ. Β. Acrylonitrile; fifth, anhydrides of unsaturated dicarboxylic acids, ζ. Β. Maleic anhydride.

The polymers or copolymers obtained in this way, however, generally do not have so far methods of preparation
of usable as lubricating oil additives

Polymers or copolymers

of esters from unsaturated organic

Acids and from alcohols

Applicant:

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

Representative: Dr. rer. nat. J.-D. Mr. v. Uexkull,

Patent attorney,
Hamburg-Hochkamp, Königgrätzstr. 8th

Claimed priority:
France March 13, 1959

Robert Tirtiaux,

Notre-Dame-de-Gravenchon, Seine-Maritime,
and Roger Tourret, Bolbec, Seine-Maritime

(France),
have been named as inventors

properties that the viscosity index would be improved and the pour point would be lowered.

It is also known that polymeric or copolymeric esters of high-boiling alcohols are a have particularly interesting effect in terms of lowering the pour point, while polymers or mixed polymers of esters of low-boiling alcohols improve the viscosity index. Ester High boiling alcohols are those which have at least 12 carbon atoms in the alcohol component own, or esters of a mixture of different alcohols, some of the alcohols less than Can have 12 carbon atoms, provided that the average molecular weight of this mixture corresponds to that of an alcohol with at least 12 carbon atoms. However, have high molecular weight Esters with more than 18 carbon atoms have the disadvantage that they result in highly viscous polymers which the Increase the viscosity of the oil considerably. Preferential

109 649/444

The starting materials used are esters with 12 to 18 and especially with 12 to 14 carbon atoms in the Alcohol component used, or esters, which consist of a mixture of alcohols, their average molecular weight corresponds to an alcohol with 12 to 14 carbon atoms.

Esters of low-boiling alcohols are those whose alcohol component does not have more than 12 carbon atoms owns, or esters of a mixture of different alcohols, some of which more than May have 12 carbon atoms, provided that the average molecular weight is this Mixture corresponds to that of an alcohol with a maximum of 12 carbon atoms. However have low molecular weight esters have the disadvantage that the polymers obtained are only sparingly soluble in the oil. the end For this reason, esters of alcohols are used as starting material, which 3 to 12 and preferably Have 7 to 12 carbon atoms, or esters from a mixture of different alcohols, whose average molecular weight corresponds to that of an alcohol with 7 to 12 carbon atoms.

To obtain additives that improve both the viscosity index and the pour point of lubricating oils improve, the solution should therefore apparently consist of a polymerization product or copolymer consist, which consists of a mixture of esters of high-boiling alcohols and esters of low-boiling alcohols with or without the presence composed of a monomeric polymerizable compound.

This solution obviously leads to a certain result; However, if you look at the proportion of esters high-boiling alcohols in the mixture to lower the pour point, it was found that the viscosity index was reduced by the copolymer.

It must be mentioned that the ester molecules of the low-boiling and the high-boiling alcohols are randomly distributed in the macromolecules, so that one in the product obtained is not at the same time Macromolecules of esters of high-boiling alcohols and macromolecules which influence the pour point obtained from esters of low-boiling alcohols, which influence the viscosity index; rather, "kornplexe" Macromolecules are formed, the effectiveness of which is lower.

You can also imagine a mixture of polymers or copolymers, which from the concerned esters are obtained by separate polymerization or copolymerization. In this The trap would be separate macromolecules of esters of low-boiling alcohols and macromolecules obtained from esters of high-boiling alcohols. From a practical point of view, one is such Solution meaningless as two different products are manufactured using two manufacturing processes must and since a double stock keeping is still necessary. There have to be two viscous substances are mixed, which is the case with oils made from macromolecular esters of low-boiling alcohols is more difficult to perform.

However, it has now been found that polymers or copolymers can be used with great effectiveness with regard to lowering the pour point and improving the viscosity index, if the polymerization and interpolymerization are carried out in two stages, namely:

1. Polymerization or copolymerization of a batch containing esters of high-boiling alcohols contains with or without the presence of a polymerizable compound.

2. Continuation of the polymerization or copolymerization of this batch with esters of low-boiling alcohols with or without the presence a polymerizable organic compound.

In one embodiment of the invention, the polymerizable organic compound is a polar monomer, especially maleic acid monobutyl ester, which is added in the first stage.

In a further embodiment, a diluent oil is used during the polymerization, the is preferably added during the second process stage.

The following substances are essentially obtained with the new polymerization process:

1. Macromolecules of esters of high-boiling alcohols produced during the first process step and which are characterized by their ability to lower the pour point of lubricating oils to degrade and to be readily soluble in these oils;

2. Macromolecules, which have a large proportion of esters of low-boiling alcohols and a small proportion Have proportion of esters of high-boiling alcohols and from the copolymerization of the second process stage of esters of low-boiling alcohols with esters of high-boiling alcohols originate which did not take part in the polymerization during the first process step to have; these macromolecules are characterized by their ability to change the viscosity index of Lubricating oils improve and show high boiling alcohols because of the presence of esters good solubility in such oils;

3. Mixed macromolecules of esters of high-boiling alcohols and esters of low-boiling alcohols Alcohols, where the molecules of esters of high-boiling alcohols are grouped at the beginning of the chain are, while the molecules of esters of low-boiling alcohols are at the end of the chain; these arise from the continuation of the incomplete polymerization of the first process stage in the course of the second process stage, these macromolecules having a double effectiveness regarding Improvements in the viscosity and pour point of lubricating oils show and continue in these are readily soluble.

By copolymerizing with a polymerizable organic compound, all of the above defined three types of macromolecules obtained, which are also molecules of the used polymerizable Connection included. This polymerizable compound can be used during the first or second process step are added.

Finally, there is the mixture obtained by the two-stage polymerization process according to the invention of macromolecules well suited to lower the pour point, these products being good in the oils are soluble; they actually show an increased effect compared to mixtures of macromolecules, which either from a single-stage polymerization process or from a separate Polymerization processes can be obtained.

One can easily detect the presence of a small amount of esters even in the first process step.

allow boiling alcohols mixed with esters of high boiling alcohols; it is further just as well possible, a small amount of higher-boiling esters during the second process step To use alcohols which are mixed with esters of low-boiling alcohols. With these additions there is a further formation of mixed macromolecules. In general, should be in the to be polymerized Batch percentage (based on weight versus total weight of ester) of esters of high-boiling alcohols in the first process stage, preferably between 100 and 25% and better still between 60 and 40%, while the proportion of low-boiling esters is preferred between 0 and 75% and better between 40 and 60%. The higher the boiling point, the better low-boiling alcohol esters can be added to the batch. The in the second procedural stage too polymerizing batch contains esters of low-boiling alcohols preferably in an amount (based on the weight compared to the total weight of ester) between 100 and 25% and better still between 60 and 40%> while the proportion of esters of high-boiling alcohols is preferably between 0 and 75% and better still between 40 and 60% - if If the low-boiling alcohol corresponds to one with 8 carbon atoms, this is preferred used alone.

In the case of low-boiling alcohols, it is possible to increase the proportion of esters of high-boiling alcohols, the lower the molecular weight of the low-boiling alcohol, the greater this increase is.

The ratio between esters of low-boiling alcohols and esters of high-boiling alcohols in the polymer obtained according to the invention thus results from the preferred ones given above Proportions of each procedural stage. It follows that the amount of esters of high-boiling alcohols 87.5 to 12.5% and better 80 to 40 percent by weight, based on the total weight of ester, is and that the proportion of esters of low-boiling alcohols from 12.5 to 87.5% and preferably from 20 to 60% can be.

In addition, it should be noted that a reversal of the two process steps is easy is possible, d. that is, it is possible to first polymerize (or interpolymerize) esters Carry out low-boiling alcohols and this polymerization (or copolymerization) in the presence of esters of high-boiling alcohols. In this case, however, it seems just as good to be possible to add the esters of high boiling alcohols to the batch of esters of low boiling alcohols give to prevent the formation of macromolecules of esters of low-boiling alcohols, which in the Oils are more soluble. It is nonetheless preferable to polymerize the higher boiling esters Alcohols to begin with, because of the presence of polymers or copolymers of esters high-boiling alcohols in the batch of esters of low-boiling alcohols of the second process step has the disadvantage of increasing the rate of polymerization of the latter. About that In addition, the polymer (or mixed polymer) in the last stage is characterized by a better one Solubility in oils.

The polymers and copolymers obtained according to the invention can also have detergent properties have, especially if they have alkoxy functions or are made from amino esters.

The polymers and copolymers according to the invention are intended as additives for lubricating oil compositions preferably in amounts of 0.01 to 20% and better still from 1 to 10%) based on the total weight, can be used.

The process according to the invention can be carried out by any possible polymerization or copolymerization method are executed. One can under the action of heat and under pressure as well as with catalysts, such as light, oxygen, ozone, powdered refining earth, boron fluoride, aluminum chloride, and preferably work with peroxides such as benzoyl peroxide.

The reaction is generally carried out in 2 to 100 hours depending on the catalyst and temperatures which may be between 50 and 15O ⁰ C. It is also possible to work in the presence of inert solvents such as petroleum, light lubricating oil, chloroform, etc., in order to control the reaction rate or the molecular weight; however, it is not necessary to use such solvents.

Example I.

Two copolymers were produced from batches of the same overall composition, with the interpolymerization was carried out once in one stage and then in two stages.

Al Bl Additive-
Batch Mixed
polymeric Mixed
polymerization sation
in a in two stages step
Total
Batch At
catching
Batch Composition of Batch, which is mixed should be merized in (Ge 40 weight percent) Fumarate of an alcohol with 8 carbon atoms 50 10 - Fumarate of alcohols 20th with 16 to 18 coals 0.5 material atoms 10 10 Vinyl acetate 40 20th 2V ₂ Benzoyl peroxide 0.5 0.5 Duration of the mixed polymer sation in hours 4th IV. Properties of the receiving a mixed polymer after 33% dilution in paraffin oil with a Viscosity index of 113 stringy and a viscosity of 734 5.1 cSt at 99 ^° C Appearance clear and Viscosity at 99 ° C in cSt 690

The following table shows comparative values of these two copolymers with regard to the increase

the viscosity index and the lowering of the pour point when added to a paraffin oil a viscosity index of 113 and a viscosity of 12cSt at 37.8 ° C.

⁰ O mixed Viscosity index 113 Bl Pour point, ⁰ C Bl -9 -21 polymer i - 9-15 -27 (active substance Al 139 Al -15 in the oil) 148; 142 -15 0 151 0.5 1 2

Example III

There were two copolymers A3 and B3 analogous to the previous examples from batches of the same Total composition is prepared, the interpolymerization in one and then in two stages was carried out.

Example II

According to Example I, two copolymers A 2 and B 2 were made from batches of the same overall composition produced, wherein the interpolymerization was carried out in one and then in two stages.

A2 B2 Additive-
Batch Mixed
polymeri
sation
in a Mixed
polymerization
in two stages step
Total
Batch At
catching
Batch Composition of Batch, which is mixed should be merized (in Ge weight percent) 30th Fumarate of an alcohol with 8 carbon atoms 45 15th Fumarate of alcohols - with 16 to 18 coals 30th material atoms 15th 15th 0.5 Vinyl acetate 40 10 Benzoyl peroxide 0.5 0.5 2 Duration of the mixed polymer sation in hours 4th 2 Properties of the receiving a mixed polymer after 33% dilution in paraffin oil with a vis viscosity index of 113 and a viscosity of 5.1 cSt stringy at 99 C 560 Appearance clear and Viscosity at 99 ° C in cSt 605

Composition of A3 B3 IO Batch, which is mixed Mixed
polymeri
sation Mixed
polymerization should be merized (in Ge in a in two stages weight percent) step At Fumarate of an alcohol Total catch additional with 8 carbon atoms Batch Charge Charge 15th Fumarate of alcohols j with 16 to 18 coals material atoms Maleate fumarate one ZO Alcohol with 8 coals material atoms, which 3 moles of ethylene oxide each 40 15 25 Moles of alcohol added became 25th Vinyl acetate 15th 15 - Benzoyl peroxide Duration of the mixed polymer sation in hours Qn Properties of the receiving o ^u a mixed polymer after 33% dilution 5 1 5 in paraffin oil with a 40 10 30 Viscosity index of 113 0.5 0.5 35 and a viscosity of 5.1 cSt at 99 ^° C 4th 2 2 Viscosity at 99 ° C in cSt 40 45 730 680

The following table shows comparative values for these two copolymers which are the same paraffinic base oil as in Example I were added.

The following table shows comparative values of these two copolymers after addition to one paraffinic base oil according to example I:

⁰ ο mixed polymer
(active substance
in the oil)

0.5

Viscosity index
A2 B2

113

140
148

141.5 151

Pour point, ⁰ C

A2 I B2

% Mixed Viscosity index B3 113 129 Pour point, C. B3 -9 -18 21 polymer 140 -21 -30 (active substance A3 152 A3 -21 -33 imöl) 156 -21 -33 0 128 0.5 139 1 151 2 153 4th

-9

-21 1 -27

-21- ι -33

Claims (8)

PATENT CLAIMS: 1. Process for the preparation of polymers or copolymers of esters from unsaturated organic acids and from alcohols, thereby characterized in that the polymerization or copolymerization is carried out in two stages is, the batch of one stage, based on the ester content of the same, at least 50 percent by weight an ester of an unsaturated dicarboxylic acid and an alcohol containing more than 12 carbon atoms per molecule, and that the polymerization is continued in the presence of an added charge, which is a larger Fraction of an ester of an unsaturated dicarboxylic acid and an alcohol which contains less has than 12 carbon atoms per molecule. 2. The method according to claim 1, characterized in that the alcohols _{contain an alkoxy, thioalkoxy, halogen, NH 2} -, NO ₂ -, HSO ₃ - or CN group. 3. The method according to claim 1 and 2, characterized in that the ester monoester is unsaturated Dicarboxylic acids and alkoxy-substituted, aliphatic, alicyclic or aromatic alcohols are. 4. The method according to claim 1 to 3, characterized in that the esters are unsaturated amino esters organic acids and aliphatic, alicyclic or aromatic alcohols are. 5. The method according to claim 1 to 4, characterized in that the charge at each polymerization stage contains a mixture of esters from unsaturated acids and alcohols. 6. The method according to claim 1 to 5, characterized in that the batch in one stage up to 75 percent by weight from an ester of unsaturated organic acids and alcohols with at least 12 carbon atoms per molecule and up to 25 percent by weight from esters from unsaturated acids and from alcohols with no more than 12 carbon atoms per molecule consists. 7. The method according to claim 1 to 6, characterized in that the batch in one stage up to 60 percent by weight from an ester of unsaturated organic acids and alcohols with at least 12 carbon atoms per molecule and up to 40 percent by weight of one Esters from unsaturated organic acids and from alcohols with no more than 12 carbon atoms per molecule. 8. The method according to claim 1 to 7, characterized in that the polymerization in the presence another polymerizable substance e.g. B. vinyl acetate is carried out. Considered publications:
U.S. Patent No. 2,825,717. © 109 649/444 7.61