DE1271875B - Dry lubricant - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

ClOm

German class: 23 c -1/01

Number: 1271 875

File number: P 12 71 875.1-43 (D 46548)

Filing date: February 18, 1965

Open date: 4th July 1968

Dry lubricants generally consist of a solid lubricant such as molybdenum disulfide or graphite, and a resin capable of forming a hardened film. The mix of solid lubricant and resin is applied as a film on the metal surface to be lubricated and hardened so that a dry lubricating film is formed. The solid lubricant provides the lubrication; it is held in place by the film; the film has a long-lasting lubricating effect, In many applications of dry lubricants, there is no need to close the bearing and sliding surfaces oil.

However, the known dry lubricants can only be exposed to limited heavy loads without the risk of breaking the dry film, whereby the Friction suddenly increased so much that the two metal surfaces melt together, which is special can then occur very easily when the support or sliding surface is set in motion. Many dry films, which otherwise work very well, can be affected by the sudden frictional pressure that associated with the beginning of a movement can be broken.

The present invention relates to a dry lubricant that can also be used at significantly higher loads is fully effective than that to which known dry film lubricants can be exposed. That Dry lubricant according to the invention has the further advantage that the solid contained in it Lubricants such as M0S2 have increased protection against moisture, which leads to the formation of acids is avoided.

Dry lubricant

Applicant:

Dow Corning Silicones Limited,
Toronto, Ontario (Canada)

Representative:

Dr.-Ing. E. Berkenfeld

and Dipl.-Ing. H. Berkenfeld, patent attorneys,

5000 Cologne-Lindenthal 3, Universitätsstr. 31

Named as inventor:
Rhynie Ferdinand Hollitz,
Midland, me. (V. St. A.)

Claimed priority:
V. St. v. America February 21, 1964
(346409)

The dry lubricant according to the invention consists of 40 to 85 percent by weight molybdenum disulfide, Graphite, antimony trioxide, titanium disulfide, tungsten disulfide, Bismuth, lead sulfide, lead oxide, polytetrafluoroethylene, magnesium oxide, boron nitride, calcium fluoride, Zirconium disulfide or colloidal silver or mixtures thereof, and 15 to 60 percent by weight a condensation product of an aromatic epoxy resin of the formula

CH ₂ CHCH ₂
O

CH ₃

CH ₃

OCH ₂ CHCH ₂ OH

CH ₃

CH ₃

OCH ₂ CHCH ₂
O

in which α is an integer from 0 to 100, and an organosilicon compound of the formula

"in which R is a phenyl or Ci: i-alkyl radical, R 'is halogen, an alkoxy, acetoxy, isocyanate, amino or hydroxyl group, where /; an average value from 0.8 to 3 and m from 0.1 to 3.2 and the sum of m and /; is not greater than 4. R 'is preferably chlorine.

The dry lubricant according to the invention can also have other components. Examples are solvents for plasticizing or dissolving the uncured condensation product and modifier for the aromatic epoxy resin, such as non-aromatic epoxy resins to soften the hardened dry lubricant and fatty acids and mixtures of these, such as octanoic, stearic, linseed oil, tung oil and ricinoleic acid. The fatty acids promote hardening and lubricity at low loads.

809 568/500

The dry lubricant of the invention preferably contains 5 to 40 percent by weight of the Organ o-silicon compound, through which the load capacity and the heat resistance of the film is increased.

Suitable solid lubricants are molybdenum sulfide, graphite, antimony trioxide, titanium disulfide, tungsten disulfide, Bismuth, lead sulfide, lead oxide, polytetrafluoroethylene, magnesium oxide, boron nitride, calcium fluoride, Zirconium disulfide or colloidal silver. Mixtures of these lubricants can also be used be e.g. B. a mixture of graphite and molybdenum disulfide and / or of calcium fluoride, molybdenum disulfide and boron nitride. Molybdenum sulfide, calcium fluoride, boron nitride or graphite are preferred or their mixtures.

The aromatic epoxy resins are made by reacting polyhydric phenols with polyfunctional ones Halohydrins or polyepoxides or more epoxy groups. The simplest diepoxies contain at least 4 carbon atoms, such as 1,2-epoxy-3,4-epoxybutane. The epoxy groups can by ether groups or bonds, as in bis (2,3-epoxypropyl) ether and bis (2,3-epoxy-2-methylpropyl) ether be separated from each other. Also useful are the more complex polyepoxides, such as those obtained by reacting 2 or more Moles of a diepoxide with 1 mole of a dihydric phenol or 3 or more moles of a diepoxide with 1 mole of a trihydric phenol. From polyhydric alcohols, such as mannitol, Sorbitol, erythritol or polyallyl alcohol derived polyepoxides can also be used.

r5 The polyepoxy compounds used for the purposes of the invention can have different structures and be more complex in structure as long as they do not contain groups that interfere with the implementation between the epoxy groups and the

Mixtures of these act to form complex reactive ₂ o phenolic hydroxyl groups. The polyepoxides used as ionic products by the terminal epoxy reactants should be practically free of reactive groups

be except for the epoxy and aliphatic

- C C

contain, won.

Examples of polyhydric phenols suitable for producing the epoxy resins are monophenylphenols, such as resorcinol, hydroquinone, catechol, phloroglucinol; Polyphenylphenols such as bisphenol hydroxyl groups.
Simple diepoxides of high purity can be prepared and obtained by fractional distillation in order to separate them from by-products formed during their preparation. So z. B. bis (2,3-epoxypropyl) ether or

(pyppy

(p ^ '- dihydroxydiphenyldimethylmethane), ρ, ρ'-dihy- 30 diglycidether prepared and fractionated by dh ihddi ili Gi Pdk hh Ri

droxybenzophenon, p, p-dihydroxydiphenyl, p, p-dihydroxydibenzyl, bis- (4 - hydroxyphenyl) - sulfone, 2,2-dihydroxy-l, l-dinaphthylmethane, polyhydroxynaphthalenes, such as 1,5-dihydroxynaphthalene, and polyhydroxyanthracenes or
phenyldimethylmethane.

Further examples are condensation products of simple polyhydric phenols with dichlorides, such as dichlorodiethyl ether and dichlorobutene, which have the following general formulas:

HOR [OCH ₂ CH ₂ OCH ₂ CH ₂ OR] _n OH and / or

HOR [OCH ₂ CH = CHCH ₂ OR] _n OH

in which R is the remainder of the phenol and η is at least 1. These polymeric condensation products consist of the dihydric phenol residues which are united or linked by means of and through residues of the organic dichlorides.

Of special. Interest and is useful the condensation product of complex polyhydric phenols with dibasic acids. So z. B.

Distillation to obtain products of high purity are separated. More complex polyepoxides higher molecular weights are difficult to isolate by fractional distillation, but they do

ο, ρ, ο ', ρ'-tetrahydroxydi- 35 can be used after removing them troublesome inorganic impurities and catalysts, such as alkali hydroxides, cleaned have been. The high molecular weight diepoxide or polyepoxide in mixtures with by-products, 40, such as monoepoxides, are useful for the purposes of the invention. Particularly well known and useful compounds are the reaction products of e.g. B. epichlorohydrin with a polyvalent Alcohol. A special example is the conversion of 1 mole of a trihydric alcohol indicated with 3 moles of epichlorohydrin and a catalyst. The epoxy group of epichlorohydrin reacts with a hydroxyl group of the alcohol, and then is used to produce the desired the 50 polyepoxides the chlorine from the reaction product removed. Such polyepoxides can contain less than three epoxy groups per molecule, even when 3 moles of epichlorohydrin have been reacted with 1 mole of a trihydric alcohol. Kick it

HOR

OC- (CH _{2) 4} C -OR

,OH

the condensation of adipic acid with one more- 55 obviously complex side reactions, whereby valent phenol a polymer of the general formula, products of different composition are formed

contain free hydroxyl groups or cyclic ring compounds or polymeric compounds which then be present in the final product. Nevertheless, such products can be used as polyepoxides can be used with polyhydric phenols to form the resin epoxies of the invention.

The polyepoxides can be of various small sizes

Phenols contain bis-phenol- (p, p'-dihydroxydiphenyl- 65 amounts of added monoepoxides dimethylmethane). To the extent that monoepoxides are present, they respond

The reaction with the polyhydric Phe with the polyhydric phenols with the formation of Nolen usable polyepoxides contain two or end groups or radicals that contain hydroxyl groups.

in which R is the remainder of the phenol and η is at least 1. One of the best known and preferred polyvalent ones useful for the purposes of the invention

and to the extent that such terminal hydroxyl groups are present, the complex polyepoxides contain complex epoxy-hydroxyl compounds that contain residues as well as terminal epoxy Contain terminal hydroxyl-containing residues. Present monoepoxides or monoepoxy-hydroxyl compounds do not interfere with the desired implementation, provided that it is sufficient Amount of polyepoxides exists to act as polyfunctional reactants with polyhydric phenols to serve.

The reaction conditions and amounts of the reactants to be used and the modification the reaction and optionally possible conversions are in full detail in the U.S. Patent 2,592,560.

The polyhydric phenol can optionally be combined with a polyfunctional chlorohydrin, such as the monochlorohydrins, be implemented; the following hydrins are given as examples: epichlorohydrin, Dichlorohydrin, e.g. B. glycerol dichlorohydrin, bis (3-chloro-2-hydroxypropyl) ether, 1,4-dichloro-2,3-dihydroxybutane, 2-methyl-2-hydroxy-1,3-dichloropropane, Bis - (3 - chloro - 2 - methyl - 2 - hydroxypropyl) ether and other mono- and dichlorohydrins, the are derived from aliphatic olefins, mannitol, sorbitol and other alcohols. Under the name "Polyfunctional chlorohydrin" should be understood to mean all compounds that have at least contain an epoxide and at least one chlorine atom in the molecule, and all compounds that a chlorine atom and an OH group on adjacent carbon atoms and at least one other Chlorine atom contained in the molecule. The chlorohydrin should preferably be practically free of other functional groups. Epichlorohydrin and / or glycerol dichlorohydrin are for the purpose of the invention is particularly useful.

The amounts of reactants such as the reaction conditions, variations and optional Process steps involved in the reaction of polyhydric phenols with polyfunctional chlorohydrin must be observed, can be found in all details from USA patents 2,615,007 and 2 615 008.

The uncondensed silicone part of the organo-Si compound given above is a silane or a silanol of the formula

3,3-difluoropropoxy- or CCl ₃ CH ₂ OCH ₂ CH ₂ O-; Acyloxy groups such as acetate, propionate, isobutyrate and octoate; Haloacyloxy such as β-chloroacetate and 3,3-difluoropropionate; the isocyanate group; Amino groups such as -NH ₂ , -NHCH ₃ , -NHC ₂ H ₅ , -NHCfiHii, -N (CHs) ₂ ; and groups of the hydroxylcarbyl substituted isocyanoxy class such as

CH,

CH,

QH ₅

CH,

C = N-O

C = N-O

and

C = N-O-

or a siloxane containing R and R 'groups.

R can be any monovalent aromatic hydrocarbon radical be like phenyl, tolyl, biphenyl, naphthyl, η, η-diethylphenyl, anthracenyl, Chrysenyl, or any lower alkyl radical such as methyl, ethyl, hexyl or isobutyl.

R 'can be - OH - or a hydrolyzable group such as halogens, e.g. B. fluorine, chlorine or bromine; Alkoxy groups such as methoxy, ethoxy, isopropoxy and decoxy; Polyalkoxy, such as /? - ethoxyethoxy, / i-methoxyethoxy and CH ₃ OC ₂ H ₄ OC ₂ H ₄ O-; or haloalkoxy groups, such as / i-chloroethoxy-, If the hydrolyzable group is such that the reaction with the OH groups in the epoxy results in strongly acidic or amine by-products, the condensation should be carried out at low temperatures and under anhydrous conditions in order to effect the reaction of the HR 'by-product with the oxirane groups on the epoxy resin to the smallest extent.

The preferred hydrolyzable groups are alkoxy groups.

The preparation of the organosilicon compound can be carried out in a known manner, for. B. as described in Canadian Patent 662,941, be done by condensation of the starting compounds in the Kitze. The condensation can be carried out at room temperature if the R 'group is very reactive.
The dry lubricant and the condensation product are intimately mixed; the best way is to apply it to the metal surface for hardening using a solvent.

The dry lubricant according to the invention hardens in the range from 100 to 200.degree. On curing, good films form which have the dry lubricant on the surface but prevent the dry lubricant from migrating when the film is under great pressure.
The invention is described in more detail in the following examples:

example 1

A batch of the following composition was produced: 70 percent by weight MoS ₂ , 7% graphite

and 23% of a batch composed as follows: The condensation product of 15 parts the hydrolyzate of 70 mole percent monophenyl trichlorosilane and 30 mole percent monopropyltrichlorosilane, that in half the molecular weight of methoxyisobutoxyethanol and excess silanes Toluene was hydrolyzed; and 45 parts of

O
CH ₂ ^ CHCH ₂

CH ₃

CH ₃

OH OCH ₂ CHCH ₂

CH ₃

CH,

OCH ₂ CHCH ₂

in which η is approximately equal to 2, mixed with 20 parts of xylene, 20 parts / f-ethoxyethyl acetate and 1 part of 2-ethylhexyl acid. The batch was ground in a colloid mill and diluted with toluene until it was sprayable. The mixture was sprayed onto steel V-blocks which had been blown off by means of steam and onto a pin fitting into the V-block and ^{cured at 149 °} C. for 1 hour.

The bolts and blocks used for the tests had a diameter of 0.63 cm, and they were smoothly abrasive to give a dense surface finish on the largest surface area to achieve. Before spraying the dry films, the bolts and blocks were Washed in acetone and not touched again by hand until hardening and exams ended. The bolts were made from SAE 3135 steel with a Rockwell B hardness of 87 to 90; the V-blocks were made of A151-1137 steel with a Rockwell C hardness of 20; the block angle was 96 °.

The friction values of the bolt rotating in the blocks were measured using a FALEX lubricant testing machine determined according to the step test method. According to this method, the loading of the bolt and the block is gradual and periodic Increased distances and the torsional force of the rotating bolt continuously measured.

The following results were achieved:

and 50% xylene added to make the approach sprayable. The batch was then sprayed onto a block and a bolt, cured and examined as in Example 1 by the step method.
The following results were achieved:

Torsional force Torsional force duration total
load at the beginning
the orbital time at the end
the orbital time the burden in kg 10 ⁶ dynes cm 10 ⁶ dynes cm (Minutes) 113.4 5.65 1.13 3 226.8 5.08 5.08 1 340.2 7.91 7.91 1 453.6 9.04 9.04 1 567.0 11.3 10.17 1 680.4 12.43 11.86 1 793.8 12.99 12.99 1 907.2 13.56 13.56 1 1020.6 13.56 13.56 1 1134.0 13.56 13.56 1 1247.4 ' 13.56 14.12 1 1360.8 14.69 15.25 1 1474.2 14.69 14.69 1 1587.6 15.25 15.25 1 1701 15.25 15.82 1 1814.4 15.82 15.82 1 1927.8 16.38 16.38 1 2041.2 16.95 33.9 failure after 55 seconds the By S game 2

V_Jcaami-
load
in kg Torsional force Torsional force duration (the 113.4 at the beginning
the orbital time at the end
the orbital time the burden load IO 226.8 10 ⁶ dynes cm 10 ⁶ dynes cm (Minutes) became 340.2 3.39 1.69 3 not 453.6 4.52 4.52 1 was standing-. 15th 567.0 6.21 6.21 1 held) 680.4 8.47 8.47 1 793.8 9.60 9.04 1 907.2 10.17 10.17 1 20th 1020.6 11.86 10.73 1 1134.0 12.43 11.3 1 1247.4 12.99 12.43 1 1360.8 13.56 12.43 1 25th 1474.2 12.43 12.43 1 1587.6 13.56 12.43 1 1701.0 13.56 12.99 1 1814.4 14.12 12.99 1 30th 1927.8 13.56 13.56 1 2041.2 14.12 14.69 1 14.69 15.25 1 17.51 19.77 2 35 40

A batch according to Example 1 was produced, but the graphite was replaced by 7% calcium fluoride. The batch was passed through a colloid mill and with a mixture of 50% ethylene glycol

Example 3

A batch according to Example 1 was produced, but the graphite was replaced by 7% boron nitride. The batch was passed through a colloid mill and added a sufficient amount of a mixture 50% ethylene glycol and 50% xylene added to make the approach sprayable. The approach was sprayed on a block and a bolt, hardened and by the step method as in the example 1, examined with the deviation that the block and the bolt, as known, for Corrosion protection had been subjected to a phosphate-manganese treatment.

The treated bolts were found to be excellent in the step test method as a low torsional force was found. With the final load of 2041.2 kg maintained for 1 minute, the torsional force at the beginning of this period was 12.43 · 10 ° Dyn-cm and at the end of this period 16.95 · 10 ° ⁽ⁱ Dyn-cm, which was the highest in this test Torsional force was.

B e i s ρ i e 1 4

A batch was made according to Example 1, but the 70% MoS ₂ and the 7% graphite by 60% MoSi and 10% antimony trioxide and 1%

Zirconium sulfide replaced. The batch was passed through a colloid mill and with a sufficient Amount of a mixture of 50% ethylene glycol and 50% xylene added to make the approach sprayable close. The approach was then sprayed onto four sets of blocks and bolts, hardened and, as described in Example 1, tested with the exception that the equipment sets the usual anti-corrosion treatment with phosphate-manganese, and with the further deviation that the tests were carried out with a constant load of 453.6 kg.

The four block and bolt apparatus sets endured continuous operation of on average 2 hours and 9 minutes with a load of 453.6 kg before the dry lubricating film breaks went. The first block and bolt set failed after operating for 2 hours and 14 minutes.

O
C ⁷ H ₇ CHCH ₂

CH ₃

CH,

Example 5

There were 18 commercially available dry lubricating films on V-blocks and bolts as per the recommendations the manufacturer applied and in a Falex machine after the step test according to Example 1 checked. The best of the 18 approaches failed with a load of 1474.2 kg, i.e. when one was faster Increase in torsional force was observed until the stud was welded to the blocks. The second best Approach failed at a load of 1247.4 kg. The average load capacity was to 793.8 kg.

Example 6

There were 40 parts by weight of magnesium oxide intimately in toluene with 60 parts by weight of a condensate from 95 percent by weight of a compound of the formula

OCH ₂ CHCH ₂ OH CH ₃

CH,

O
OCHCH ₂

in which m is approximately equal to 100, and 5 percent by weight of a silicone of the average formula

C ₆ H ₅

C ₆ H ₅

QH ₅

CH, OSi - O - Si - O - SiOCH,

CH,

CH,

CH,

Product of 40 mole percent 1,3,7-trihydroxynaphthylene, 10 mole percent of a compound of the formula

mixed and obtained a material that hardens on metal as a film by heating and the metal surface gives a good lubricity.

Example 7

There were 50 parts by weight of titanium disulfide intimately in acetone with 50 parts by weight of a mixed condensate mixed, which consisted of 90 parts by weight of the condensation product of equal molar Amounts of resorcinol and 1,2-epoxy-3,4-epoxybutane and 10 parts by weight of phenylethylsilanediol; the formed material hardened on metal as a film by heating and gave sliding properties to the metal surface.

Example 8

There were 60 parts by weight of polytetrafluoroethylene intimately mixed in diethyl ether with 40 parts by weight of a co-condensate, which consisted of 70 percent by weight of the condensation product of 40 mol percent phloroglucinol and 60 mol percent bis (2,3-epoxypropyl) ether and 23 percent by weight Tolyltriethoxysilane, 2 percent by weight trimethylchlorosilane and 5 percent by weight ethyl silicate. It a material was formed which cured as a film by heating on a metal surface and the Metal surface imparted sliding properties.

Example 9

70 percent by weight of lead sulfide were intimately mixed with 30 parts of a mixed condensate, which consisted of 60 percent by weight of the condensate O
CH ₂ CHCH ₂ CHCH ₂

OH

O
CH ₂ CHCH ₂ CHCH ₂

CH

35

⁴⁰

40 mole percent bis (2,3-epoxy-2-methylpropyl) ether and 10 mole percent 1,2-epoxypropane and 40 percent by weight a compound of the formula

CH ₃

Il I

CH ₃ C - OSi

CH,

CH ₃
OSi-

CH,

Il

OCCH ₃

10

A material was formed which hardened as a film on heating on a metal and which Metal surface bestowed sliding properties.

Example 10

There were 80 parts by weight of colloidal silver intimately in benzene with 20 parts by weight of a batch mixed, which consisted of 50 percent by weight of the condensation product from equimolecular amounts from

OCH ₂ CH = CHCH ₂ O

and glycerol dichlorohydrin, and 50 percent by weight

809 568/500

Anthracenylhexyltetra - β - ethoxyethoxydisiloxane. A material was formed which hardened on metal as a film when heated and gave sliding properties to the metal surface.

Example 11

There were -85 parts by weight of finely divided bismuth intimately in cyclohexane with 15 parts by weight of a Mixed approach, which consisted of 40 percent by weight of the condensation product of equimolar Share the connection

Example 12

Example 10 was repeated, but the silicone indicated there was replaced by

(CH ₃ X ₁₅ SiO

'75

Ii ii

\ J - oc (ch ₂ ) ₄ co

and 1,4-dichloro-2,3-dihydroxybutane and 60 percent by weight of a polymer of the average formula

C (CH ₃ ),

A material was formed that hardened on the metal as a film upon heating and the metal surface Sliding properties bestowed.

Claims (1)

Claim: (CH ₃ ) ^ SiO (OCH ₂ CH ₂ Cl); A material was formed which, when heated, hardened as a film on metal and the metal surface conferred good sliding properties. Dry lubricant, consisting of 40 to 85 percent by weight molybdenum disulfide, graphite, Antimony trioxide, titanium disulfide, tungsten disulfide, bismuth, lead sulfide, lead oxide, polytetrafluoroethylene, Magnesium oxide, boron nitride, calcium fluoride, zirconium disulfide or colloidal silver or their Mixtures, and 15 to 60 percent by weight of a condensation product of an aromatic Epoxy resin of the formula CH ₂ CHCH ₂
O CH, CH ₃ OCH ₂ CHCH ₂ OH CH, I. c CH ₃ OCH ₂ CHCH ₂
\ /
O in which α is an integer from 0 to 100 and an organosilicon compound of the formula R "R; SiO ₄ . _m _ " in which R is a phenyl or Ci-s-alkyl radical, R 'is halogen, an alkoxy, acetoxy, isocyanate, amino or hydroxyl group, where η has an average value from 0.8 to 3 and m from 0.1 to 3.2 and the sum of m and η is not greater than 4. Considered publications:
British Patent No. 869,559.