CS265929B1 - Water-soluble lubricant especially for metal forming - Google Patents

Abstract

Water-soluble lubricant, especially for metal forming comprises at least two out of eleven of triethanolamine autocondensation products formulas I to XI, wherein η = 1 to 4. Its The preparation consists in being on triethanol the amine is treated with an acid-based catalyst with an active hydrogen atom at temperature 240-280 ° C for 1/2 to 2 h at rt atmospheric pressure.

Description

The invention relates to a water-soluble lubricant, in particular for metal forming.

Water-soluble lubricants contain mainly soaps, esters of fatty acids with polyhydric alcohols or amines. Of the amines, alkanolamines are used in the form of salts or esters with fatty acids.

The disadvantage of these lubricants is that they usually form more or less stable emulsions with water. Working with such lubricants requires precisely defined working conditions, i.e. temperature, pH, lubricant concentration in water and more. The stability of emulsions of these lubricants can be improved by the addition of an emulsifier, which, however, often impairs the lubricating properties of the emulsion.

These disadvantages are overcome by a composition according to the invention which contains at least two of the eleven triethanolamine anticondensation products of formulas I to XI, where n = 1 to 4. The lubricant is prepared by treating triethanolamine with 240 active acids for 1/2 to 2 h at atmospheric pressure. A specific property of these products is the strong yellow-green fluorescence visible even in daylight, which is carried by unspecified pi-electron systems of conjugated multiple bonds in the vicinity of the free electron band of the nitrogen atom. The measure of the depth of condensation is the amount of water released, increasing viscosity, refractive index, average molecular weight, relative fluorescence intensity in the range of 380 to 440 nm.

Such a product prepared by condensation of triethanolamine shows, for example, in a rolling lubricity test compared to various top metal forming lubricants, a lubricity which allows a half-thickness strip to be rolled from a test sheet under comparable conditions:

The preparation of the lubricants according to the invention is evident from the following examples.

Example 1

To 1000 g of triethanolamine, 1 g of a 98% strength by weight solution of sulfuric acid was added with vigorous stirring, and the reaction mixture was poured into a 2,000 ml three-necked flask equipped with a thermometer, stirrer and condenser. The apparatus was heated to 230 ° C in an oil bath, which initiated the autocondensation reaction. After two hours, the reaction was quenched by gradually cooling the reaction mixture. During self-condensation, at which the temperature rose to 250 DEG C., 160 ml of condensation water were released from the reaction mixture and a very viscous, water-soluble, water-soluble product was obtained with the following characteristics: refractive index at 20 DEG C.-1.538 DEG, kinematic viscosity - 487.2 mm ² s ^-1 , maximum fluorescence emission spectrum - 405 nm, residual triethanolamine content 0.8 wt. The main components of the lubricant thus prepared are the substances of formulas I, II, IV and V.

Example 2

The reaction was carried out according to the method of Example 1, except that a 1% strength by weight solution of trichloroacetic acid was used as the catalyst. Upon treatment with 1000 g of triethanolamine, 100 ml of condensation water and 0.06 ml of chloroform, formed by decomposition of the catalyst, were released at 250 DEG C. over 1 hour. The reaction product had a refractive index at 20 DEG C. of 1.498 ° C, a kinematic viscosity of 255 mm.s, a maximum fluorescence emission of 410 nm and a residual triethanolamine content of 3.8% by weight. The main components of this lubricant are substances of formulas I, IV, VI, IX.

Example 3

The reaction was carried out according to the method of Example 1, except that a solution of 0/5% by weight of acetic anhydride was used as catalyst. When 1000 g of triethanolamine were treated, 75 ml of condensation water were released at 260 DEG C. over a reaction time of 30 minutes. The reaction product had a refractive index of - 1.495 at 20 ° C, a kinematic viscosity of 198.8 mm s ^-1 , a maximum fluorescence emission of 398 nm and a residual triethanolamine content of 4.8 wt. The main components of this lubricant are the substances of formulas I, II, IV, V and VII.

The products of all three examples were incorporated on a test laboratory rolling mill as lubricants in comparison with conventional mineral oil B4 and a top lubricant for rolling chlorinated paraffin alloy steel tubes.

Lubricant

Thickness of rolled strip after 10 passes (.10 m ^- ®)

according to example 1 85 according to example 2 90 according to example 3 93 mineral oil B4 195 alloy rolling oil steel based on chlorinated paraffins 155

Test conditions: steel strip 15 mm wide, 0.5 mm thick, rolling force 35 kN, rolling speed 0.2 m / s, ten times the passage of lubricant between the rollers.

Claims (2)

A water-soluble lubricant, in particular for metal forming, characterized in that it contains at least two of the eleven triethanolamine self-condensation products of the formulas I to XI, where n = 1 to 4. 2. A process for preparing a lubricant according to claim 1, characterized in that the triethanolamine is treated with a catalyst based on acids with an active hydrogen atom at a temperature of 240 to 28 ° C for 1/2 to 2 hours at atmospheric pressure. 1 drawing 265 929 Η / O - GH _o -GH _o -N-CH _o -GH - O-GH _o -CH _o -N-GH _o -GH _o / OH I dd · 2 2 2 2.2 2n ch ₂ -gh _{2 -oh} óh ₂ -ch ₂ -oh H / O - CH ₂ -CH ₂ -N-CH - CH - O- CH = CH-N-CH ₂ ~ CH ₂ / _n OH II Oh ₂ -ch ₂ -oh Oh ₂ -ch ₂ -oh H / O - CH ₂ -CH ₂ -N-CH ₂ -CH ₂ -O-CH = CH-N-CH = CH / _n OH ...... III Oh ₂ -CH ₂ -OH Oh ₂ -CH ₂ -OH / CH _o -CH _o -O-CH - CH _o x H / O - CH - GH - N ^Z ^ N-CHa-CH- / OH IV ^V GH ₂ -GH ₂ -O-GH ₂ -CH 2 * * / GH = CH-O-GH = GH, H / O - CH - GH - N ^Z N-CH - GH- / OH V ^X GH = CH-O-CH = CH / GH _O -CH _O / GH - CH * O ^{Z d} N-CH _Q -CH ₉ -O-CH 2 -GH ₉ -N (* * 0 gh ₂ -ch ^ 'ch ₂ -ch ^ ...... VI / CH = CH zCHp-CHpx 0 ^Z N-GH _{of the} -0-CH-CH-CH _{about 9} N ^Z ^ 0 CH = GH GH ₂ -CH 2 ...... VII / CH = CH / CH = CH _X ^Z 0 / N-CH _{of the} CH -0-CH _of CH "-N- (/ 0 CH = CH ^Z 22 \ _{CH = CH} / ...... VIII / CH ^ -CH, 0 ^Z ^ / N-CHP CHP / O CHP CHP-N-CH ₂ -CH ₂ ^z / CH ₀ CH ₀ CH ₀ ^-0-Z -GHa ^ N-GHp-CHpAOH ⁱⁿ gh ₂ -gh ₂ -o-ch ₂ -gh ^ ⁿ ..IX / Ch ₂ -ch ₂ -O-ch ₂ -ch ₂ n-ch ₂ -ch ₂ -o-ch ₂ -ch ₂ -n ch ^ ch ^ o-ch ^ ch ^ .......................... X GH „= GH - N-GH _o -CH _o -O-CH ₉ -CH ₉ -N-GH = CHd · d dc d। C. CH = CH ₂ CH = CH ₂ ............. XI Severography, n. P., MOST