DE1745359B2 - PROCESS FOR THE MANUFACTURING OF LUBRICATING OIL - Google Patents

Description

3 °

wherein R is a group with a polymerizable carbon double bond, such as the vinyl, isopropenyl, Acryloxyalkyl or methacryloxyalkyl group, and R 'are identical or different radicals from the group consisting of hydrogen, alkyl or aralkyl and two adjacent radicals R 'can be closed to form a ring is used.

2. The method according to claim 1, characterized in that the polymerizable derivative of the Imidazole is a 2-alkyl substituted imidazole derivative is used.

3. The method according to claims 1 and 2, characterized in that as polymerizable Derivative of the imidazole of l-vinyl-2-methyl- and / or the l-Viny! -2-ethyl-imidazole is used.

4. The method according to claims 1 to 3, characterized in <o that a base polymer having a molecular weight from 5000 to 150,000 is used.

5. Process according to claims 1 to 4, characterized in that a base polymer with a Molecular weight of 10,000 to 70,000 is used.

6. Process according to claims 1 to 5, characterized in that the polymerization of the unsaturated Nitrogen compound in the presence of a base polymer and, in addition, of monomeric nitrogen-free esters of acrylic, methacrylic, itaconic or fumaric acid is carried out.

Lubricating oil additives with dispersing and detergent effects are already known from additive products Certain polyamines are composed of polyisobutylene. Their detergent effect becomes that in practice However, it does not do justice to the requirements that arise. Furthermore, as dispersing additives without noteworthy detergent effect of graft copolymers of nitrogen-containing monomer mixtures on a oil-soluble base polymer known. Such graft copolymers are, for example, according to US Pat. No. 3,087,875 by radiation-chemical polymerization of nitrogen-containing monomers in the presence of polymers higher methacrylic acid ester produced The products manufactured by radiation-chemical methods have gained no practical importance

In contrast, lubricating oil additives according to German patent specification 11 18 971 are produced on an industrial scale, by free-radical polymerization of 40 to 85% monomers leading to oil-soluble polymers and then mixed with a nitrogen-containing monomer, whereupon the polymerization up to full turnover is continued. Products produced in this way have a satisfactory dispersing effect then on. if they have a content of, for example, at least 8 percent by weight of N-vinyl-pyrrolidone in the Polymer included.

Products of improved effectiveness are obtained according to the main patent 15 20 696 if one in Presence of a base polymer that

a) from acrylic or methacrylic acid esters with at least 8, preferably 12 to 16 carbon atoms in Alcohol residue or fumaric or itaconic acid esters with i> up to 18 carbon atoms in the alcohol residue or from mixtures of these esters with one another or with smaller amounts of acrylic or methacrylic esters with 1 to 4 carbon atoms in the alcohol residue, Aminoalkyl esters of acrylic or methacrylic acid, vinyl acetate or mixtures of these monomers, or

b) from isobutylene

built up is an unsaturated compound with a tertiary nitrogen atom polymerized by free radicals, whereby the proportion of this unsaturated compound 2 to 30 percent by weight, based on the base polymer, matters. The preferred range is 3 to 4.5 percent by weight. As a nitrogenous compound N-vinyl-pyrrolidone is preferably used. The term "radical polymerization" is used here triggered by radical-forming polymerization initiators such as azo compounds or peroxides, however did not understand the polymerization triggered by high-energy rays. Additions of about 3% Such graft copolymers give lubricating oils good dispersing properties, but leave im MWM diesel test run over 50 hours only 75 points according to that of E. Kruppke (»The Engine Testing of Crankcase Lubricatin Oils «. 1962, pp. 53 to 67, “Engine Testing and Evaluation of Crankcase Lubricants «) for the detergent effect established evaluation method reach.

An increase in effectiveness beyond this value can only be achieved by significantly increasing the Part of the nitrogen-containing monomer is possible.

It has now been found that the detergent action of the products according to the main patent is increased considerably can be if called nitrogen-containing unsaturated

Compound polymerizable derivatives of imidazole the general formula

in which R is a group with a polymerizable carbon double bond, such as the vinyl, isoprope.iyl, acryloxyaSkyl or methacryloxyalkyl group, and R 'is identical or different radicals from the group consisting of hydrogen, alkyl and araiky! and two radicals R 'on adjacent carbon atoms can be closed to form a ring, can be used. These monomers are used in amounts of 2 to 30 percent by weight, preferably 2 to 10 percent by weight. The products obtained by this process are graft copolymers whose main chain consists of acrylic or methacrylic acid esters with at least 8, preferably 12 to 16 carbon atoms in the alcohol radical or fumaric or itaconic acid esters with 8 to 18 carbon atoms in the alcohol radical or from mixtures of these esters, if appropriate in minor amounts from acrylic or methacrylic esters with 1 to 4 carbon atoms in the alcohol radical, aminoalkyl esters of acrylic or methacrylic acid. Vinyl acetate or mixtures of these monomers. \ snd the graft branches of which are at least partially made up of one of the imidazole derivatives identified in more detail above, possibly the remainder of one or more unsaturated compounds with a tertiary nitrogen atom, the weight of the grafts being 2 to 30%, based on the weight of the main chain, auttnaclu.

In addition to units of nitrogenous monomers, the grafting branches can also contain units of s; ick ', toff freer. Contain esters of acrylic, methacrylic, ItaUotv or fumaric acid. Such mixed graft polymers satc arise z. B. then, if the production d » Base polymer used ester mixture has not been completely polymerized, so that the not polymerized part is polymerized by grafting together with the nitrogen-containing monomers.

The superior detergent effectiveness of imidazole derivatives in graft copolymers was surprising and not foreseeable, since similarly constructed nitrogen compounds, e.g. B. vinylpyrrolidone, a similar detergent effect at least as long as not ^erre: blank surfaces, such as the proportion of these nitrogen compounds is not gcstsigert according to the invention to be used amount of the polymerizable imidazole derivatives in multiples.

The special effect of the polymerizable lirtidazole derivatives is already evident in the descendants of the child's body. / .. B. the N-vinylimidazole. clear, but is particularly evident in the case of the imidazole derivatives which are alkyl-substituted in the 2-position. Of these, special reference should be made to the derivatives of 2-methyl-, 2-ethyl-, 2-isopropyl- and 2-t butylimidazole. Because of their good technical accessibility, preference is given to those imidazole derivatives which have an N-vinyl group as the polymerizable group. Further suitable groups are

z. B. the N-Methacryloxyäthyl- or the N-Acrylamidoäthylgruppe. With simultaneous appreciation of the technically easy accessibility, the good polymerizability and the induction of high dispersing and detergent effect are the 1-vinyl-2-methyI-imidazole and l-vinyl-2-ethylimidazole in particular to highlight.

The polymerization is usually a solution polymerization in oil with one of the known radical-forming initiators, such as. B. Azodiisobutyric acid dinitrile, Diethyl azodiisobutyrate, tert-butyl perbenzoate or tert-butyl hydroperoxide, advantageously in the absence of air, carried out. Polymerization in other solvents is possible in principle.

A lubricating oil that contains about 6% of a lubricating oil additive, which in the context of the invention is 4.5% on the base polymer, l-vinyl-2-methylimidazole has been made has been relocated, leaves the MWM diesel test run Get 92 points over 50 hours while getting an equivalent result with an equal high addition of a graft polymer of N-vinylpyrrolidone is only achieved if more used as 30% of this monomer for the preparation of the graft polymer. Using 15% vinylpyrrolidone, on the other hand, only reaches about 85 points.

The molecular weight of the graft copolymers is essentially determined by that of the base polymer used certainly

The molecular weight of the end product increases compared to the base polymer due to the graft polymerisation depending on the amount of the grafting monomer. For lubricating oil additives that are in the proportions that have hitherto been customary in lubricating oils are to be used, one generally starts from Base polymers with molecular weights from 400,000 to 1 million. However, it is preferred To use base polymers with molecular weights below 150,000 and therefore lubricating oils to add correspondingly larger amounts of the resulting graft polymer. The life of the alloy This increases lubricating oils considerably without causing undesirable piston deposits comes, which to the skilled person as a consequence of the addition of polymers as lubricating oil additives are known. These properties of the products produced according to the invention make the use of additional ones Detergents are unnecessary.

fcs has also been found that such products prepared by the process of the invention for a Bd.s'spolymcrisat with molecular weights 10,000 to 70,000 has been used to reduce wear and tear in considerably reduce highly sensitive bearings, in particular if they are used together with small amounts of a Zin.k-di ^ lkyidithiophosphats. The method of the invention is therefore with carried out with particular advantage with such base polymers. The economic disadvantage that of these particularly low molecular weight graft polymers give the lubricating oil relatively large amounts, namely about 10 to Wo, have to be added, there is the advantage that the total amount of necessary »additives by saving an additional detergent dip. previously usual range of quantities does not or does not exceed WRsent'icli. Basic polymerisation with molecular weights below 5000 are useful in making the Schmiävölzusatz of the invention no longer suitable

The lubricating oil additives according to the invention can be added to any commercially available base oil. Her However, excellent properties come into their own when they are relatively large Amounts of a low molecular weight graft polymer S used together with a low viscosity base oil will. Such combinations can be referred to as true multigrade oils

In the examples below, the production of the graft copolymers of the invention described. The molecular weights denoted by Mw of the Base polymers are weight averages. They were made in butyl acetate solution by the light scattering method measured at 20 ° C with the Photo-Gonio-Diffusometer from Sofica. When performing and rs Evaluation of the measurement, the instructions enclosed with the device were followed exactly

The dispersing and detergent action of the obtained Graft copolymers were then used by E. ICruppke (“The Engine Testing and Evaluation of Crankcase Lubricants "in" The Engine Testing of Crankcase Lubricating Oils ", 1962, pp. 53 to 67 "Report of the Institute of Petroleum Conference" Brighton, May 17-19, 61) described MWM diesel test run over 50 hours assessed on the basis of assessment is the cleanliness of the piston. Complete cleanliness is scored with 100 points, total soiling with 0 sparked rated

example 1

90 parts by weight of a copolymer (with an Mw of about 70,000, determined by light scattering) from 10 parts by weight of methyl methacrylate and 90. Weight parts of a mixture of methacrylic acid esters of fatty alcohols (average carbon number 14.0), dissolved in 100 parts by weight of mineral oil (viscosity of Mineral oils at 98.89 ° C = 4, OcSt) are mixed with 10 parts by weight of l-vinyl-2-methylimidazole and 0.5 parts <parts by weight tert-butyl perbenzoate solution (50% in Mineral oil) and polymerized for about 8 hours at 130 ° C. with stirring and with the exclusion of air. After a Reaction times of 1 and 3 hours are added in each case 0.1 part by weight of the tert-butylbenzoate solution and polymerized

The MWM diesel test run gives 91 points according to the test method described.

Example 2

95 parts by weight of a copolymer (Mw about 30,000) of 4 parts by weight of methyl ylate, 10 parts by weight of methyl methacrylate and 86 parts by weight of a mixture of methacrylic acid esters of fatty alcohols (average carbon number 14.0), dissolved in 100 parts by weight of the in Example 1 mentioned mineral oil, are mixed with 5 parts by weight of 1 -V ^: nyl-2-methylimidazoi and 0.5 'by weight of tert-butyl perbenzoate solution (50% in mineral oil) and polymerized for about 8 hours at 130 ° C with stirring and with the exclusion of air

The piston cleanliness after the MWM diesel test run is rated with 90 points.

Example 3

The procedure of Example 1 is repeated with the difference that instead of l-vinyl-2-methylimidazole 1-vinyl-2-ethylimidazole is used.

The graft copolymer obtained gave a piston rating of 89 in the M WM diesel test run Score points.

Example 4

90 parts by weight of a copolymer (Mw about 70,000) of 45 parts by weight of butyl methacrylate and 55 Parts by weight of a mixture of methacrylic acid esters of fatty alcohols (average carbon number 14.0), dissolved in 100 parts by weight of mineral oil, 10 parts by weight of l-vinyl-2-methylimidazole and 0.5 parts by weight tert-butyl perbenzoate solution (50% in mineral oil) added and with stirring and exclusion of air polymerized for about 8 hours at 130 ° C. After a reaction time of 1 and 3 hours, in each case 0.1 Parts by weight of the tert-butyl perbenzoate solution are added and polymerized. After the MWM diesel test run the piston cleanliness is rated with 90 points

Example 5

Example 1 is repeated with the difference that instead of 1-vinyl-2-methylimidazole, 1-vinylimidazole is used.

86 points are achieved in the M WM diesel test run.

Example 6

Following the procedure of Example 1, a graft copolymer is made with a base polymer generated by the Mw 500,000.

The M WM diesel test run gives 88 points.

Comparative experiment

85 parts by weight of a copolymer (Mw about 70,000) from 10 parts by weight of methyl methacrylate and 90 parts by weight of a mixture of methacrylic acid esters of fatty alcohols (average carbon number 14.0), dissolved in 100 parts by weight of mineral oil, 15 parts by weight of N-vinyl-pyrrolidone and 0.5 parts by weight tert-butyl perbenzoate solution is added and the mixture is stirred and with exclusion of air for about 8 hours at 130.degree polymerized

After a reaction time of 1 and 3 hours, 0.1 parts by weight of the tert-butyl perbenzoate solution are added yielded and polymerized.

85 points are achieved in the M WM diesel test.

Claims (1)

Patent claims: 1. Process for the production of lubricating oil additives, in which in the presence of a base polymer, that of acrylic or methacrylic acid esters with at least 8, preferably 12 to 16 carbon atoms in the Alcohol residue or fumaric or itaconic acid esters with 8 to 18 carbon atoms in the alcohol residue or from Mixtures of these esters with one another or with smaller amounts of acrylic or methacrylic esters with 1 to 4 carbon atoms in the alcohol radical, aminoalkyl esters of acrylic or methacrylic acid, vinyl acetate or mixtures of these monomers, an unsaturated compound with a tertiary one Nitrogen atom is radically polymerized, the proportion of these compounds based on the Base polymer used, 2 to 30 percent by weight makes up, according to main patent 15 20 696, characterized in that as unsaturated Nitrogen compound a polymerizable derivative of imidazole with the general formula