DE1258538B - Metalworking lubricants - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

ClOm

German KL: 23 c - 1/04

Number: 1 258 538

File number: S 95223IV c / 23 c

Filing date: January 28, 1965

Open date: January 11, 1968

A wide variety of lubricants have already been proposed for drawing metals, such as soft metals, especially lead, solid non-metallic lubricants such as waxes, hard soaps and solid lubricating greases, as well as liquid lubricants such as mineral oils containing fatty substances and soaps have been blended. It is also known to treat the metals beforehand with suitable substances, like lime or phosphate.

After a widely used drawing process ίο the metal to be processed is first immersed in a warm phosphate solution with a Phosphate coated and then rinsed off, apply soap lubricant to the phosphate coated metal, such as sodium oleate or calcium stearate, applied and dried. Then the metal comes with Machined drawing tools. This method has disadvantages in that it requires multiple operations are, the implementation is uncomfortable and the liquid itself and that from the phosphate solution escaping vapors are highly corrosive. In addition, the finished metal shows a gray to deep dark color, which leads to complaints, since a shiny metal is required.

The invention now relates to the use of a homopolymer with a molecular weight of 10,000 to 1,000,000 from monomers of the formula RCH = CH ₂ , in which R is hydrogen, halogen, a carboxyl or hydrocarbon group having 1 to 8 carbon atoms, or a copolymer with a molecular weight of 20,000 to 800,000 from several of these monomers or together with an -olefin with 3 to 5 carbon atoms or another vinyl compound, optionally in combination with a paraffin wax with a melting point of 49 to 63 ⁰ C and / or a microcrystalline wax with a melting point of 54 to 71 ⁰ C and / or a heavy wax with a melting point of 62 to 85 ° C as a lubricant for metalworking.

It has been found that when using the homo- or Copolymers can work metal well and in particular up to a size reduction of about 70 to 85% pulls _ and the workpiece still has a shiny appearance. Very suitable For the purposes of the invention, copolymers, in particular copolymers of ethylene and another monomeric compound such as propylene. Particularly suitable lubricants contain a polymer and in particular a copolymer in combination with a wax.

Metalworking lubricants

Applicant:

Shell International Research

Maatschappij N.V., The Hague

Representative:

Dr. E. Jung, patent attorney,

8000 Munich 23, Siegesstr. 26th

Named as inventor:
Stewart James Beaubien,
Oakland, Calif. (V. St. Α.);
Neville Harold George Daniels,
Petone (New Zealand)

Claimed priority:

V. St. ν. America January 30, 1964 (341405)

The preparation of the polymers is known per se, and no protection is claimed for the method of preparation within the scope of the invention. In general, the preparation is carried out at temperatures between room temperature and about 15O ⁰ C and at pressures below about 35 kg / cm ² down to atmospheric pressure. Suitable catalysts consist of a compound of a transition metal and of organometallic compounds which can act as reducing agents.

For the preparation of the polymers suitable monomers are, for. B. hydrocarbons such as ethylene, propylene and styrene, and vinyl compounds such as vinyl chloride and vinyl acetate and monomers of the formula RCH = CH ₂ , in which R is an aliphatic, cycloaliphatic or aromatic hydrocarbon radical having 1 to 8 carbon atoms.

The homopolymers depend on the type of monomer used and the specific polymerization conditions either amorphous or highly crystalline substances. Suitable stereospecific crystalline polymers are obtained, for. B. made of propylene, 3-methyl-1-butene, 4-methyl-1-pentene and 4-methyl-1-hexene.

Copolymers can be produced by polymerizing one or more of the aforementioned monomers with one another. Very suitable copolymers are obtained from ethylene and another monomer, preferably a C ₃ -C ₅ α-oil film or a vinyl compound such as vinyl acetate. Copolymers of ethylene and propylene can be used particularly well. The copolymers generally have an average

709 718/391

3 4

Molecular weight between 20,000 and 800,000 and the chain of the individual wax molecules with the unpreferred between 200,000 and 400,000. branched chain of the polymer used

Suitable copolymers can also be coordinated. The degree of branching of a mixed poly-polymerization of unsubstituted diolefins, merisates of ethylene and a higher α-OleSn such as butadiene, or of alkyl-substituted diolefins, 5 is determined by the molar ratio of ethylene such as isoprene, and subsequent hydrogenation of the poly to this higher olefin. It is desirable in itself produce merisates. if a limited range of unbranched

In particular, the amorphous or relatively few chain units in a copolymer with the crystalline polymers can be coordinated with other different types of wax, materials such as a wax can be blended. So that io which are present in common petroleum wax,
If a polymer can be blended with wax, petroleum waxes must contain a large number of waxes that are at least partially soluble in this wax. species. An example of this is given in the USA patent-Therefore, in general, for this purpose, straight-writing 2,915,447, in particular in Table II there, chain polymers with a long carbon chain are given. It can be seen from this that a paraffin is suitable which contains practically no hydrophilic funk- 15 wax with an average melting point of 50.6 ⁰ C tional side groups, such as hydroxyl or aryl about 86 mol percent normal paraffins with 22 to groups. Typical representatives of such poly- contains 27 carbon atoms per molecule. Other merisate are derived from -olefins, for example, on the one hand contains a paraffin wax with a medium polyethylene and polypropylene, as well as mixed poly melting point of about 59.4 ° C 72 mol percent wax merisates of ethylene with other monomeric 20 with 26 to 31 carbon atoms per molecule.
Compounds such as α-olefins and vinyl acetate. The mixture of wax and polymer contains

The solubility of a polymer in wax generally depends on about 5 to 95 percent by weight and essentially on its molecular weight. preferably 50 to 90 percent by weight wax.
For example, a polyethylene or poly- The metal to be processed is coated with a dry

relatively low molecular weight propylene film of the lubricant of the present invention so low a degree of crystallinity that it drew well and then z. B. edit with a drawing tool Wax is soluble while polyethylene or tet. The lubricant can be applied High molecular weight polypropylene a lot by putting the workpiece in a melt of the same are more crystalline and are therefore much less immersed in. However, such an approach is because of Loosen wax. In general, the molecular 30 required high temperatures and formation weight of polymers that are not blended with wax, relatively thick films on the workpiece can be and are expedient for the production of the invention. It is therefore generally more advantageous suitable lubricants, no larger than about the lubricant in dissolved or dispersed 500,000; in general it is actually much smaller. Apply form.

In general, mixed polymers are used for this purpose, which are amorphous or relatively less crystalline merisate of ethylene, which 60 to 99 weight polymers, which in a suitable solvent percent and in particular 75 to 95 percent by weight can be easily solved by means of such Containing ethylene, preferred. Apply the solution to the Wer.citüüc, whereby

For the modification of the polymers, each of the latter can be coated with a thin polymer film, suitable wax can be used, but will be. The use of volatile, combustible petroleum waxes is preferred. Petroleum waxes are in the solvent, however, for safety reasons, literature also as paraffin wax or microcrystalline is not expedient. A wax is therefore preferably referred to, the microcrystalline waxes aqueous dispersion of the polymer or of the (also called amorphous waxes) being used in the dewaxing wax-polymer mixture. Gesigaste of residual lubricating oils, paraffin waxes, on the other hand, dispersions contain 1 to 15 percent by weight and, when dewaxing lubricating oil distillation fractions, preferably about 5 to 10 percent by weight of the amount obtained. Such distillate paraffin waxes lubricant, based on the dispersion,
In general, they have melting points between about Very suitable aqueous dispersions can be used

48.9 and 62.8 ° C, preferably between 51.7 and 60 ° C using a mixture of petroleum wax on. 50 and an ethylene-α-olefin copolymer

Microcrystalline waxes, which are only small in quantity. Such copolymers contain about gen of straight-chain paraffins and 80 to 95 moles of ethylene per mole of a C ₃ -C _{5 a} ; -oleans consist mostly of highly branched and naphthenic and have an intrinsic viscosity of 2 to 5 deciliters waxes, melt about between 54.4 and per gram. Particularly preferred Mischpoly-71.1 ⁰ C, in particular between about 60 and 65.6 ⁰ C. 55 merisate contain 85 to 93 weight percent ethylene

The waxes with a higher melting point are for and 15 to 7 percent by weight of a C ₃ -C ₅ -X-OIeUnS. the purposes of the invention are particularly suitable. The wax-polymer mixture preferably includes heavy distillate waxes, which are obtained from high 40 to 95 percent by weight wax and 5 to 60 boiling lubricating oil distillate fractions by weight copolymer. Mixtures of 67 to exhibit and, in general, melting points between about 60 77 weight percent wax and 33 to 23 weight 62.8 and 85 ⁰ C, and high-melting percent copolymer are bssonders low. Paraffin waxes that can be separated from microcrystalline wax by. Of course, dispersions can also be separated by fractional crystallization. Polymers used without added wax

When using waxes, such as dispersions of polyisoprene, poly-moderate several types of wax combined. Wax and 65 butadiene, ethylene-propylene-Mtschpolymsrisaten and Polymers can be made up of a wide range of polyethylene.

mix with each other. Example Dar through the use according to the invention dss

wise it is very desirable that the unbranched molecular lubricant progress achieved arises from dsn

the following comparison tests. Unless otherwise stated, the trial rods had one 0.635 cm in diameter, made of AISI C 1018 type fluoro iron, and was in for 1 hour has been remunerated in a protective atmosphere at 900 ° C. These rods were connected one after the other by means of a Series of drawing tools treated, with no intermediate lubrication made between the individual pulls until failure of the lubricant occurred, as evidenced by the presence of Surface damage on the bars revealed. It became the following series of drawing tools (R-5-Carboloy angle of 8 °) used to achieve the specified area reductions:

Size of the pulling tool, mm 4.77 3.81 3.16 2.54 2.03

Area reduction,% 42 38 36 31 36

Total reduction,% 42 64 77 84 90

Before the pulling tests, a thin film of lubricant was applied to the test bars by one in a cyclohexane solution or in an aqueous dispersion of the lubricant in question dipped in and then air dried.

In experiment A, an ethylene-propylene copolymer (EPC) with an intrinsic viscosity of 3.1 deciliters per gram in decalin at 150 ° C. and with an average molecular weight of 4 · 10 ^{5 was used} as a lubricant. The molar ratio of ethylene to propylene in this copolymer was 9: 1. In experiments B and C, the copolymer in question was used together with wax as a lubricant. The lubricant mixture contained 30 percent by weight copolymer and 70 percent by weight residual paraffin wax with a melting point of about 83.9 ° C. _ In experiment D, a copolymer of ethylene and vinyl acetate (EVC) was used. This copolymer was mixed with petroleum wax, and the lubricant mixture contained 30 percent by weight copolymer of ethylene and vinyl acetate, 35 percent by weight mixture of 30% copolymer and 70% residual paraffin wax as well

ίο 35 percent by weight of a paraffin wax. This Mixture was applied in the form of a hot cyclohexane solution (f = 60 ° C), since the copolymer precipitates out of solution when this is allowed to cool.

For comparison, tests with conventional lubricants were also carried out. At attempt E. Sodium oleate soap and in Experiment F a lubricated test rod pretreated with phosphate was used. The oleate film was applied by placing the test rod in a 60 ° C. 10% aqueous solution of sodium oleate for 5 minutes (Degree of purity: 99.5%) immersed, then allowed the excess solution to run off and the rod Air dried for 24 hours. In the other experiment, the test bars were with a Zinc phosphate solution pretreated. These rods, which were gray in appearance and due to the etching were then 'lubricated with a lubricant'.

For comparison purposes, drawing tests were also carried out with a different polymer. In experiment G, the rods were immersed in a 10% strength aqueous solution of a polyethylene glycol polymer with an average molecular weight of 6000 to 7500 and then immersed dried.

The results obtained in these experiments are summarized in the table below.

lubricant Pulling speed
age Pulling force Size of the drawing tool in millimeters 4.77 3.81 3.16 2.54 2.03 test
No. in kilograms
for one
36% happened happened happened fails m / min. Surfaces happened happened happened happened fails EPC in 2V ₂ weight 0.457 reduction happened happened fails A. percent solution in
Cyclohexane 91.44 645.90 happened happened happened happened fails 4% EPC wax 0.457 649.55 happened happened happened fails - B. Solution in cyclohexane 91.44 621.42 happened happened happened happened fails 10% EPC wax 0.457 641.83 C. Suspension as aq 91.44 602.80 happened happened fails - - ger latex 668.14 happened happened happened fails - EVC wax in 4% strength 0.457 happened fails - - - D. Solution in cyclohexane 91.44 621.42 happened fails - - - Sodium oleate in 10% 0.457 662.25 happened happened happened happened fails E. aqueous solution 91.44 641.83 happened happened happened happened fails Phosphate pretreatment 0.457 688.10 happened happened fails F. 91.44 708.97 happened happened fails Polyethylene glycol in 10% - 0.457 744.35 happened happened fails G iger aqueous solution 91.44 636.39 happened happened fails Wax, 10% 0.457 644.10 42 64 77 84 90 H Dispersion 91.44 610.99 Total area reduction 659.52

From these test data it can be seen that the polymers according to the invention have a high molecular weight both alone and in combination with a wax of a soap as a lubricant for the Drawing process are far superior and produce equally good results as the usual phosphate pretreatment. lead treatment method with regard to area reduction. In contrast, polymers with low Molecular weight, like the solid polyethylene glycol, completely unsuitable. In addition, according to the invention Machined rods have a shiny appearance, in contrast to those with a phosphate pretreated bars, which are gray and sometimes even very dark.

Claims (1)

Claim: Use of a homopolymer with a '. Molecular weight from 10,000 to 1,000,000 from mono- mers of the formula RCH = in which R denotes hydrogen, halogen, a carboxyl or hydrocarbon group with 1 to 8 carbon atoms, or a copolymer with a molecular weight of 20,000 to 800,000 from several of these monomers or together with an «-olefin with 3 to 5 carbon atoms or another Vinyl compound optionally in combination with a paraffin wax with a melting point of 49 to 63 ° C and / or a microcrystalline wax with a melting point of 54 to 71 ⁰ C and / or a heavy distillate or residue wax with a melting point of 62 to 85 ° C as a lubricant for metalworking. 709 718/391 12.67 © Bundesdruckerei Berlin