JPS5828320B2 - Jiyunkatsuzaisoseibutsu - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The use of fatty layer diesters and complex esters as synthetic lubricants has gained widespread acceptance due to the outstanding viscosity properties of their compositions over a wide temperature range.

However, in certain applications involving severe operating conditions, the load-bearing capacity of these synthetic lubricants may be insufficient to provide adequate lubrication without the use of additives to reduce the amount of friction and wear encountered. is insufficient.

These additives, called extreme pressure (EP) agents, are generally sulfur, chlorine, phosphorous or lead compounds that react with metal surfaces to provide a lubricating film that can withstand very high operating temperatures. do.

Although these additives effectively increase the load carrying capacity of the lubricant system, they also create fouling and sludge problems, especially when copper, magnesium, aluminum, silver and other metals are used. This causes problems in systems where

In some cases, corrosion is too severe, so rather than integrating BP additives into the lubricant, it is recommended to reduce the unit load, improve the surface finish, increase the viscosity of the oil, or apply pressure from outside the system. It may be desirable to use or take similar measures.

If the load-bearing capacity of the synthetic ester lubricant is sulfur,
If increased without the addition of chlorine, phosphorous and lead containing compounds, corrosion and other problems normally associated with these BP agents are thus minimized or completely eliminated. , which is desirable and highly advantageous.

It would be particularly useful if an EP additive were available that was easily prepared and compatible with synthetic ester lubricating oils.

A non-corrosive and non-sludge EP additive useful for improving the load-bearing capacity of inventive synthetic lubricating oils has now been discovered.

The compositions useful in this invention contain hydroxy ester compounds derived from the reaction of certain dimer acids with certain glycidyl esters.

The glycidyl esters are derived from fatty acids containing 5 to 22 carbon atoms.

Particularly useful glycidyl esters are derived from neo-acids.

A preferred hydroxyester composition is obtained from the reaction of about 0.45 to 0.55 equivalents of a glycidyl ester derived from a neo-acid with a dimer acid containing preferably 75% by weight or more of a C362 basic acid. It is a half ester.

The useful EP additives are added to synthetic ester lubricants, including diesters, polyesters, and composite esters, at levels ranging from o, oi to about 5 φ by weight of the total lubricant.

DETAILED DESCRIPTION The hydroxy ester compound used in the present invention is a dimer acid obtained from the polymerization of unsaturated fatty acids and containing at least 75% by weight of a C36 dibasic acid with the formula is a branched or straight-chain alkyl group having a carbon atom, and is obtained by reacting with about 0.45 to 0.55 equivalents per equivalent of dibasic acid of a glycidyl ester having a branched or straight chain alkyl group having a carbon atom, and mainly having the formula , R has the same meaning as above).

The glycidyl ester used to obtain the group [1] is formed in a mesomorphic manner by the reaction of shrimp chlorohydrin with a 7/l/potassium metal salt of C5-22 fatty H and has the following formula: R is defined as for 1 above).

Preferred glycidyl esters are derived from branched chain acids and have the general formula: where R1, R2 and R3 are] to 4
carbon atoms and the total number of carbon atoms among the three groups is from 4 to 10 in total).

Although glycidyl esters derived from neo-acids are preferred for the present invention, glycidyl esters of pelargonic acid, heptanoic acid, valeric acid, isostearic acid, oleic acid and the like may also be conveniently used. Since the compositions of the invention necessarily contain groups of formula [1] and also free carboxyl groups, the acids used to prepare the hydroxyester compounds are necessarily dibasic acids, i.e. contain at least two carboxyl groups. The acid must be

Although two carboxyl groups are essentially required to obtain the compounds of the invention, the acid may contain three, four or more carboxyl groups.

However, as a practical matter, the greater the number of carboxyl groups in the starting acid, the greater the complexity of the product1 and thus the EP properties of the additive become less significant.

Half esters are formed when dibasic acids are used.

Regardless of the number of carboxyl groups, the acid should have a molecular weight greater than about 480 and therefore necessarily contain at least 30 carbon atoms.

Acids meeting the above requirements are conveniently prepared by the polymerization of unsaturated supra-Zummer fatty acids containing about 18 to 22 carbon atoms.

These monomer acids have one or more sites of unsaturation and include acids such as oleic acid, lyluic acid, eleostearic acid, lycylic acid, lyluic acid, and the like.

A method for the formation of high molecular weight polymeric acids is disclosed in US Pat.
, 482, 761: 2,793, 219 and 2,
No. 793,220.

By varying the reaction conditions used in the polymerization, the proportions of dimers, trimers, and higher acids can be varied.

Dimer acids obtained when two molecules of monomer acids are combined are particularly useful for the present invention.

These acids are commercially available and sold under the names Empol dimer and trimer acids (manufactured by Emery Industries).

The average number of carbon atoms in these products is about 36 to 54.

Preferred acids for forming the hydroxy ester additives of the present invention contain at least 75 parts by weight of C362 basic acid and the remainder of the acid composition is trimer acid, i.e. 034
It consists of tribasic acids and contains small amounts of tetramer or higher acids.

Particularly useful acid compositions include 85 or more 03
It is a 62 base acid.

Hydroxy ester compounds useful as EP agents for the present invention are obtained by reaction of the glycidyl esters described above with polybasic acids.

This reaction is preferably carried out in the absence of a catalyst, although a catalyst may be used if desired to increase the rate of reaction.

The reaction rate is generally sufficient so that no catalyst is required, and also, in the absence of a catalyst, a pure reaction product is obtained so that costly washing steps for removing catalyst residues can be omitted.

The reaction may be carried out over a wide temperature range; however, from an economic point of view it is desirable to have a fast reaction rate and temperatures of about 150 to 250°C, and more preferably 180 to 220°C, are used.

Reaction times depend on the temperature and the particular reactants used.

The reaction is usually carried out at a temperature of about 200°C for about 1 to 2 hours.

The proportions of reactants are determined by the specific composition and glycidyl
It will vary depending on the number of carboxyl groups of the acid to be reacted with the ester.

For example, for the preferred C362 basic acid, about 0.
Particularly useful compositions when 3 to 0.7 equivalents of glycidyl ester are used per equivalent of diprotic acid and about 0.45 to 0.55 equivalents of glycidyl ester are used per equivalent of diprotic acid. You can get things.

This latter range of reactants is used to provide one sufficient glycidyl function to react with about half the carboxyl groups, thus yielding the half ester.

Glycidyl esters are calculated to give less than one free carboxyl group in the molecule, although if an acid containing more than one carboxyl function is used the equivalence ratio will be changed accordingly. The amount given will never be exceeded.

The resulting composition may be a product mixture, some of which contains at least one free carboxyl and at least one type 1 group, as long as its average composition meets the requirements specified above. as long as it has the desired degree of substitution.

The amount of hydroxy ester compound used can vary within a wide range, but preferably these EP
The additive is present in the synthetic lubricant in an amount of about 0.01 to about 5 times the total lubricant.

Preferably, the additives of the present invention make up about 0% of the lubricant composition.
．． A range of 1 to 1.5 weights may be included.

At these levels, the hydroxy ester compound is an effective EP agent that improves the load-bearing capacity of the lubricant and also significantly reduces metal corrosion and sludge properties in both petroleum-based and synthetic ester lubricants. reduce

The additives of the present invention may be used with other materials normally included in lubricating compositions such as antioxidants, detergents, dyes, antifoam agents, viscosity modifiers, additional corrosion inhibitors, EP agents, and the like.

Compounds of the above type include p-amino diphenylamine, phenyl-α-naphthylamine, phenothiazine,
Includes polynotyl acrylate, silicon-containing polymers, polyisobutylene, petroleum sulfonates, sorbitan monooleate, barium salt of sulfurized isononyl phenol, and the like.

Typically, these additional ingredients account for about 0.0 of the total lubricant composition.
It will weigh from 1 to about 10 Da.

In contrast, lubricants in which the hydroxy ester compounds of this invention are useful additives are synthetic monoester lubricants, including diester polyesters and complex ethers.

Diester lubricating oils are fully esterified with monohydric alcohols in the open form and have the following general formula: %, where n is an integer ranging from about 6 to about 15, and R
' is a branched or straight chain hydrocarbon group containing about 1 to 6 carbon atoms).

Preferred diesters of the above type are derived from adipic, azelaic and sebacic acids and C3 or CO branched alcohols.

Useful diester synthetic lubricating oils include di-2-ethylhexyl sebacate, di-2-ethylhexyl isosebacate, di-n-nonyl adipate, di-n-heptyl isosebacate, and the like.

Also useful are diesters prepared from oxo alcohols, which are mixtures of branched-chain aliphatic alcohols obtained by reaction of olefin oligomers with carbon and hydrogen oxides in the presence of suitable catalysts and subsequent hydrogenation. be.

Illustrative examples of these diesters include di-03 oxoadipate, di-C1o oxoadipate, di-C3 oxoazelate, di-C7 oxoadipate, di-C1
3 oxopimelate and similar.

Diesters derived from the reaction of fully esterified glycols with monocarboxylic acids are also useful synthetic substrate lubricants for use with the EP additives of this invention.

Polyesters obtained from the reaction of polyhydric alcohols and monocarboxylic acids can also be used as synthetic oils.

These include products derived from trimethylolpropane and pentaerythritol and acids such as caproic, caprylic and pelargonic acids to form triesters and tetraesters.

Polymerizable forms of pentaerythritol can also be used to obtain synthetic polyester lubricating oils.

Complex esters used as synthetic base oils are of the type obtained by esterification of dicarboxylic acids with glycols and monofunctional alcohols or by esterification of monocarboxylic acids.

In general, a wide range of esterbase synthetic oils may be used and will have superior load bearing capacity when small amounts of the EP agent of the present invention are incorporated therein.

Synthetic ester oils and methods for their preparation are known in the art and described in various patents and publications.

The examples presented below are intended to more fully illustrate the invention, but they are not intended to limit the scope of the invention in any way.

In the examples, all parts and percentages are by weight unless otherwise noted.

Example 1 An acid-terminated hydroxy ester having essentially the formula:
C362 basic acid (Empol 1010) with a molecular weight of
It was prepared by reacting 1 mole (5 sl) of a neo-acid (cardura E) with a glycidyl ester of a neo-acid (cardura E) having an average molecular weight of about 245.

The reaction was carried out at 220° C. for 15 hours under a nitrogen blanket.

The final product has an acid value of 39, a hydroxyl value of 68, and a flash point of 520°.
F and an ignition point of 630 F.

Example 2 The half-ester prepared in Example 1 was evaluated in a synthetic ester-based lubricant.

The base lubricant used was 50% isovaleric acid, 25%.
Approximately 93 parts of a complex ester derived from monobendanilis IJ l-- and 1 mole of azelain esterified with an acid mixture consisting of pelargonic acid and 25 grams of a C6-1 basic acid mixture (Emfac 1210 low molecular weight acid) It was a blend of approximately 7 parts polyester consisting of the reaction product of acid, 2 moles of monopentaerythritol, and 4 moles of C6 to monobasic acid (Emfac 1210).

The EP agent of Example 1 was blended into a base lubricant at a level of 0.5φ and i, o%, and the load bearing capacity of the lubricant was determined by Faderal festMethod 5tan.
dard 4791a, Method 6508 on a Ryder Machine.

The results obtained are reported in Table 1.

The data clearly show that incorporating small amounts of hydroxy ester compounds into synthetic ester lubricants significantly increases the load carrying capacity of the lubricant.

Furthermore, the lubricating oil so composite has excellent oxidative stability, resists sludge formation and accumulation and has extremely low corrosivity to copper, magnesium, iron, aluminum and lead. is found.

Similar results have been obtained with other synthetic ester lubricants containing the hydroxy ester additive.

The unexpected discovery that hydroxy ester compounds function as acceptable EP agents for synthetic ester lubricants shows that even when structurally similar additives are used, no noticeable improvement in EP properties is observed. This is shown by the fact that it was not possible.

For example, a C362 basic acid is completely esterified with a 50:50 mixture of methyl alcohol and 2-ethyl hexyl alcohol and
Half esters of 362 basic acids were prepared and evaluated in synthetic ester base oils.

In both cases, no noticeable improvement in load-bearing capacity was observed.
In fact, for its complete ester, Ryder Gea
A substantial reduction in load-bearing capacity was observed when brought to the r test.

Claims (1)

[Scope of Claims] 1. (a) A major amount of a synthetic ester lubricant selected from the group consisting of diesters, polyesters and composite esters; and (b) C36 lubricants obtained from the polymerization of unsaturated fatty acids.
a dimer acid containing at least 75% by weight of a dibasic acid; and a dibasic acid of a glycidyl ester having the formula: The hydroxyester compound obtained from the reaction with about 0.45 to 0.55 equivalents per equivalent is about 0.01 to 5 weight φ weight based on the total lubricant composition, and the hydroxyester compound mainly has the formula ( A non-corrosive, low-sludge synthetic ester lubricant composition with improved EP properties, characterized in that it is a half-ester having the formula (R has the same meaning as above).