CS276771B6 - Functional liquid - Google Patents

Abstract

A functional fluid composition for use as a hydraulic fluid, lubricant, cutting fluid or drilling fluid which comprises (a) from 20 to 98% by weight water (b) from 0 to 80% by weight of a glycol, and (c) from 0.5 to 25% by weight of a thickening agent prepared by (a) reacting one mole of a monofunctional active-hydrogen-containing compound having at least 10 carbon atoms with between 20 and 400 moles of one or more alkylene oxides and (b) thereafter reacting the product of step (a) with a diepoxide in an amount such that the molar ratio of diepoxide to hydroxyl groups in the product of step (a) is between 0.2:1 and 5:1. The fluid may further comprise functional components for preventing wear and corrosion and also 0.5 to 15% by weight of a non-ionic, cationic, anionic or amphoteric surfactant. i

Description

(57)

Functional fluid, usable as hydraulic fluid, lubricant, drilling fluid or cutting coolant! a liquid, based on water, glycol and a thickener, containing 20 to 98% by weight of water, 1 to 80% by weight of glycol and 0.25 to 25% by weight of a thickener, prepared by reacting one mole of a monofunctional compound containing active hydrogen and having at least 10 atoms % of carbon with 20 to 400 moles of one or more alkylene oxides and subsequent reaction of the resulting reaction product with diepoxide in an amount such that the molar ratio of diepoxide to hydroxy groups of the reaction product of the monofunctional hydrogen-active compound and alkylene oxide is between 0.2:

: 1 and 5: 1.

CS 275771

AND

CS 276 771 36

The invention relates to water-based functional fluids which can be used, for example, as hydraulic fluids, lubricants, drilling fluids or cutting coolants.

Functional liquids based on a mixture of water and polyether glycols are well known and used for a variety of purposes, such as cutting coolants, hydraulic fluids and the like.

These water-based hydraulic fluids, known as HF-C fluids, typically contain about 15 to 30% high viscosity polyatherglycol and 35 to 45% water, wherein <

the remainder, up to 50, constituting a simple glycol and small amounts of ingredients known to those skilled in the art. i “1 o X

Usually these hydraulic fluids have a viscosity of 32 to 68 mm · s ^- at 40 C. *

Recently, efforts have been made to reduce the polyether glycol content of these functional fluids. For example, it would be most desirable to reduce the polyether glycol content of hydraulic fluids to 10% or even less. 3e also attempts to produce what can be described as High Water Content (HWBF) fluids, typically containing 50-38% water, by additionally draining some or all of the glycol.

Attempts to reduce the polyether glycol content of hydraulic fluids give rise to the problem of reducing the viscosity of the hydraulic fluid. This is because standard polyether glycol fluids do not have sufficient thickening capacity. By simply increasing the viscosity of the polymer, the desired effect is not achieved because the possibility of increasing the viscosity of the solution is limited and the polymer becomes unstable under high shear conditions.

For example, it has been suggested in US Patent 4,767,555 and US Patent 4,288,639 to achieve the desired viscosity of said hydraulic fluids by adding small amounts of water-miscible materials that increase the viscosity of hydraulic fluids by intramolecular coupling in solution. These materials are known as associative thickeners.

The hydraulic fluids described above as high water content (HWBF) fluids containing: usually only small amounts of simple glycol as an antifreeze additive or containing no single glycol, have a number of disadvantages compared to HFCs containing water and glycol.

Although HWBFs typically exhibit sustained shear stability, i.e., the viscosity of the fluid remains stable over long periods of operation, it nevertheless exhibits a temporary loss of viscosity in high shear areas as evidenced by loss of flow rate and pump efficiency in hydraulic systems, in other words, they lack temporary shear stability.

In these transient loss of viscosity conditions, the lubricating ability of the liquid also suffers.

This is maintained only by additives that provide limit lubrication (EP additives). Although these additives have been successfully developed, these conditions can lead to increased wear. In addition, the best of these additives are often toxic, hydrolytically unstable and harmful to the environment.

The viscosity index of these liquids is often low, which can cause problems when starting the pumps.

HWBF fluids are sensitive to water loss, which can have a dramatic and adverse effect ¹ on the viscosity of the liquid.

U.S. Pat. No. 3,538,033 discloses a family of polyether diepoxide derivatives which can be used as thickeners in textile printing emulsions, cosmetic emulsions, aqueous pigment suspensions, and the like.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide functional fluids suitable for the above-described purposes that have good durability and transient stability, include low associative thickening / melt concentrations ^: good resistance to water loss resulting in viscosity changes, good viscosity indices and which would retain hydraulic lubrication under high shear conditions.

CS 276 771 BS

The present invention provides a functional fluid useful as a hydraulic fluid, lubricant, drilling fluid or coolant cutting fluid; based on water, glycol and thickener, characterized in that it contains 20 to 98% by weight of water, 1 to 80% by weight of glycol and 0.25 to 25% by weight of thickener, prepared by reacting one mole of a monofunctional compound containing active hydrogen and having at least 10 carbon atoms with 20 to 400 moles of one or more alkylene oxides and subsequent reaction of the resulting reaction product with diepoxide in an amount such that the molar ratio of diepoxide to hydroxyl groups of the reaction product of the monofunctional active hydrogen and alkylene oxide reaction is between 0.2: 1 and 5 : 1.

The functional fluid according to the invention may optionally also contain components for preventing abrasion and corrosion.

The invention solves the above object by using a thickener as defined in U.S. Pat. No. 3,538,033 for the aforementioned purposes and the manufacturing technology described in detail below.

With regard to the water content of the composition, it is preferred that it is a 35 to 95% functional liquid, preferably 45 to 80%.

As a glycol, any water-miscible glycol, i.e. monoethylene glycol and monopropylene glycol and their low molecular weight oligomers, i.e. having at most 6 ethylene and / or propylene glycol units, can in principle be used. Preferably, monoethylene glycol, diethylene glycol or triethylene glycol is used. It is preferred that the glycol represents 20 to 60% of the functional liquid.

The first step of preparing a thickening agent is to react the monofunctional active hydrogen-containing compound with one or more alkylene oxides. By active hydrogen-containing compound is meant a compound which contains hydrogen detectable by the Zerewitinoff active hydrogen assay. Such compounds are alcohols, phenols, thiols, fatty acids, and amines. Preferred compounds are C ₆ to ^C-20 3 ^E dnosytné alcohols or thiols Ο θ ^ _2Q to C ₁₆ alkylphenols and C to C aliphatic amines _2Q.

The active hydrogen-containing compound is alkoxylated with one or more alkylene oxides using a cell base or Lewis acid catalyst. Typically, one or more alkylene oxides selected from the group consisting of ethylene oxide, propylene oxide, and isomers of butylene oxide are used as alkylene oxides. Suitably, 20 to 400 moles of alkylene oxides are added to the active hydrogen-containing compound, of which 20 to 100 moles. preferably 65 to 85 mol. % is ethylene oxide and 0 to 80%, preferably 15 to 35% is propylene oxide and / or butylene oxide.

In the second stage of production, the product of the first stage is reacted with diepoxide. The diepoxide may in principle be any organic compound with two epoxy groups. Suitable diepoxides are those containing from 4 to 30 carbon atoms and include vinyl cyclohexene dipoxide, bisphenol A and epichlorohydrin condensate and the like. Preferably, the diepoxide is used in an amount such that the molar ratio of epoxide groups to hydroxyl groups in the product of step 1 is in the range of 0.2 to 1 to 5 to 1. The second stage of the process can hardly be catalyzed by cell or Lewis acid.

It is preferred that the amount of thickening agent is 2 to 10% by weight functional

- 2-1 liquid. It is also preferred that the thickener itself have a viscosity of greater than 4000 mm s at 40 ° C.

With respect to anti-wear additives, these are usually salts of organic derivatives of sulfur, phosphorus or boron or carboxylic acids with metals or amines. They are usually aliphatic or aromatic C 1 salts. up to C ₂₂ carboxylic acids, sulfur acids such as aromatic sulfonic acids, phosphorus acids such as hydrogen phosphate esters, and analogous sulfur compounds such as thiophosphoric and dithiophosphoric acids. Many longer anti-wear agents are well known to those skilled in the art.

The metal corrosion inhibitors may be organic or inorganic, for example nitrites, hy3

Droxylamines, neutralized fatty acid carboxylates, phosphates, sarcosines and metal succinimides, etc. are preferred. Amines such as alkanolamines such as ethanolamine, diethanolamine and triethanolamine are most suitable. For example, aromatic triazoles may be used as non-ferrous metal inhibitors.

It is preferable to add 0.5-15% of a surfactant which interacts with the thickening agent. The agent may be nonionic, cationic, anionic or amphoteric. Examples of suitable surfactants include linear alcohol alkoxylates, nonylphenol alkoxylates, fatty acid soaps, amine oxides, etc. Most preferred are linear secondary alcohol alcoholates, e.g., fatty ones, available from BP Chemicals under the trademark Softanol. The surfactants act synergistically with the associative thickener so that the desired viscosity can be achieved with a lower total thickener content in the composition compared to using the associative thickener alone.

In addition to the above, the functional liquid may also optionally contain other components such as extreme pressure additives, antifoams, antimicrobial agents and the like, which are well known to those skilled in the art. It is also possible to add other known thickeners and thickeners if desired.

The functional liquids of the invention can be prepared by mixing the four main components and any other necessary materials in a container of appropriate size.

In preferred embodiments of the invention, i.e. liquids containing 20% or more glycol, it has been found that these liquids have transient shear stability. This increases the ability of these fluids to provide hydrodynamic lubrication under high shear conditions. The presence of 20% or more of glycol and a thickener co-surfactant also improves the apparent viscosity index of liquids versus liquids containing no glycol or surfactant.

In the functional liquids of the invention containing less than 20 percent glycol, the transient shear problem is also addressed by the use of the inventive associative thickening agents po2-1 with a high intrinsic viscosity of the polymer, e.g. greater than 20,000 mm s at 40 ° C. Under high shear conditions, the concentration achieved by association is lost when fluids transiently shear. However, the viscosity of the liquid is maintained at an average value by normal thickening of the polymer of high viscosity, usually at 10-20 mm s at 50 ° C. This reduces the loss of pump efficiency and ensures hydrodynamic lubrication. This solution also contributes to improving the liquid loss properties and viscosity index of the liquid.

The functional fluids according to the invention are particularly suitable as hydraulic fluids for piston, gear or vane hydraulic pumps, motors and hydraulic systems such as hydraulic dredges, robots and the like.

The invention will be illustrated by the following examples.

Example 1

A chamber sample of oleyl / cetyl alcohol (85/15) was updated with potassium hydroxide (0.3% by weight of the resulting alkoxylate), dried and treated with a 70/30 (w / w) mixture of ethylene oxide and propylene oxide at 115 to 125 ^° C to an alkoxylate having an experimentally determined molecular weight of 6,000 (by hydroxyl determination).

500 g of the above non-neutralized alkoxylate were reacted at 130 ° C for 3 hours with 15.9 g of bisphenol A condensate with epichlorohydrin (Epikote 028 - ex Shell). The remainder of the catalyst was removed by treatment with magnesium silicates, yielding an associative thickening agent which in itself had a viscosity of 5000 mm s at 40 ° C. A 10% aqueous solution at 40 ° C had a viscosity of 193 mm ² s -1.

CS 276 771 85

Example 2

500 g of the above non-neutralized alkoxylate of Example 1 was reacted at 130 ° C for 3 hours with 31.8 g of bisphenol kondenz condensate with epichlorohydrin, the catalyst was removed by treatment with magnesium silicate to give an associative thickening agent having itself viscosity 17,300 MRA ^{2 -} ^ at 40 ° C. Its 10% aqueous solution had a viscosity of 2100 mm ² s -1 at 40 ° C.

Example 3

The oleyl / cetyl alcohol (05/15) sample was reacted as described in Example 1 with a mixture of 80/20 ethylene oxide and propylene oxide to give an alkoxylate of 5,000 molecular weight.

300 g of the aforementioned non-neutralized polyalkylene glycol were reacted with 14.0 g of vinylcyclohexenediepoxide at 140 DEG-150 DEG C. for three hours. The resulting associative thickening of the 2 &apos; leaching agent itself had a viscosity of 40,000 mm &lt; 2 &gt; s at 40 [deg.] C and its 10% aqueous solution had a viscosity of 1,427 mm ^{&lt; 2} &gt;

Example 4

A commercial sample of oleyl / cetyl alcohol (85/15) was reacted as described in Example 1 with a mixture of 75/25 ethylene oxide and propylene oxide to give an intermediate of 2,950 molecular weight and then with another ethylene oxide alkoxylate of 3,100 molecular weight.

000 g of the above non-neutralized polyalkylene glycol was reacted

With hours at 140-150 [deg.] C., 175 g of vinylcyclohexenediepoxide were obtained to give an associative 2-1 thickening agent whose 10% aqueous solution had a viscosity of 1742 mm s.

Examples 5 to 8

Dodecan-1-ol. tetradocan-1-ol, hexadecan-1-ol and octadacan-1-D1 were reacted with mixtures of 80/20 ethylene oxide and propylene oxide under catalysis of the base to give 6,000 molecular weight alkoxylates. 200 g of each alkoxylate were reacted with 9.4 g of vinylcycloxane diamine as described in Example 3 to give four associative thickening agents. The products were used to compare viscosity in solution against the length of the hydrophobic chain.

Example Comparison 5 5 7 8 Product Breox 75W18000M C-12 C-14 C-16 C-10 Viscosity, without 2 -1 admixtures, mm s at 40 ° C 18 000 22 400 10 400 27 400 21 400 Viscosity, 10%, mm ² s ^-1 at 40 ° C 5 117 451 4 080 34 000

h a standard polyglycol thickener

Example 9

Thickener (3%) of Example 1 was formulated into a hydraulic fluid with a viscosity of 45 mm% ^- '· at 40 ° C containing water (35%), diethylene glycol (50%), a fatty acid and morpholine. This fluid was then tested for 1 hour in a four ball (IP294) at 40 kg, which produced a 0.55 mm scuff line, a result similar to that obtained with a similarly treated hydraulic fluid using 15% of the usual a polyglycol thickener.

The same thickener at a concentration of 7% in a high water content viscosity

1 ο mm s ”at 40 ° C was passed through the Kurt Orban shear stability test device (IP294) 5 times without detecting a permanent loss of solution viscosity.

Example 10

The thickener of Example 4 was incorporated at 8% into a hydraulic fluid containing 30% diethylene glycol and 58% water, the remainder being anti-wear and anti-corrosive additives. The hydraulic fluid was circulated for 24 hours in a 7 kw Vickers PFD-5 rotary piston pump at 50 ° C and 170 bar. The flow rate, which may be directly related to the viscosity of the liquid, was monitored to show viscosity in the high shear areas of the pump. The hydraulic fluid was compared to a similar hydraulic fluid containing only 10% diethylene glycol and 80% water, and 3 other hydraulic viscosity associative thickeners, i.e. epoxy, containing no diethylene glycol.

Absolute viscosity 10 ^J Pa.s at 40 ° C

Example 10 38

10% OEG liquid 27

Liquid from a commercial low viscosity associative thickener 21 based on a commercially available low-

itoxylate fatty alcohol in olefinic Apparent viscosity in shear area 10 “ ³ Pa.s % high shear viscosity Flow pump 1 / m 31 B1% 14.6 12 44% 14.11 3.4 16% 12.46

Example 11

The thickener of Example 1 (6.2%) and 5 moles of linear secondary C-12/14 alcohol ethoxylate (1.55%) (Softanol 50 - from BP Chemicals) were mixed with diethylene glycol (40%) and water (50%). . The rest consisted of anti-wear, anti-corrosion and anti-foam agents (2.25%). A hydraulic fluid having a viscosity of 45.5 mm s at 40 ° C was obtained. The following values were found.

Scratch in four-ball machine, mm (lh, 40 kg, XP239):

0.61, shear stability (IP294),% viscosity change: -7

Example 12

The associative thickener of Example 3 (3.6%) and 5 moles of linear secondary C-12/14 alcohol ethoxylate (0.8%) was mixed with diethylene glycol (20%) and water (73.4%).

-1

The rest were additives (2%). A hydraulic fluid having a viscosity of 49.3 mm s at 40 ° C was obtained. The following data were determined.

4-ball abrasion groove, mm (lh, 40 kg, IP239): 0.62, shear stability (IP294),% viscosity change: -5.

Example 13

The associative thickener of Example 3 (5.4%) and 12 moles of linear secondary C-12/14 alcohol ethoxylate (3.6%) (Softanol 120 - from BP Chemicals) were mixed with diethylene glycol (39%) and water (50%). ). The fringe consisted of anti-abrasion, anti-corrosion and Drip-foam rj.i ·,;? · Jc ·. 2 -1 'D ·· ingredients (2%). This gave a hydraulic fluid having a viscosity of 46.8 mm 3 at 40 ° C.

The following data were determined.

4-ball abrasion groove, mm (lh, 40 kg, IP239): 0, G1, shear stability (IP294),% viscosity change: + 2.9.

CS 276 771 BS

Example 14

Thickener 2 of Example 2 (5.0 and 12 moles of linear secondary C-12/14 alcohol ethoxylate (1.25%) was mixed with diethylene glycol (20%) with water (70), the remainder being anti-wear, anti-corrosion and anti-foam agents (3, 75%) to give a hydrophilic liquid having a viscosity of 46.1 mm &lt; 2 &gt; s @ -1 at 40 DEG C. The following data were determined.

Abrasion groove in 4-ball apparatus, mm (1 h, 40 kg, IP239): 0.63

Example 15

To demonstrate the effect of diethylene glycol on the apparent viscosity index, two ISO 68 fluids were prepared from the thickener of Example 3. Liquid 1 contained 6.0 percent thickener, 30 percent diethylene glycol and 54 prooent water. Liquid 2 contained 5.0 percent thickener and 95 percent water. The combined effect of the presence of diethylene glycol and a slightly increased thickener content in liquid 1 results in a liquid having a substantially lower viscosity at 20 ° C than that observed for liquid 2, indicating that the apparent viscosity index of liquid 1 is higher than liquid 2.

Liquid 1 Liquid 2

Example 16

Viscosity at 40 ° C, mn ^ s ^-1

72.5

71.5

Viscosity at 20 ° C, nin ^ s ^"1

505

985

To demonstrate the effect of thickener coefficients on the apparent viscosity index, two liquids having a viscosity of 550 mm ^s at 40 ° C were prepared as follows: Liquid 1 contained 6.0 percent of the thickener of Example 2, 4.0 percent of 12 moles of ethoxylate C-12/14 linear secondary alcohol, 10 percent diethylene glycol and 80 percent water. Liquid 2 contained 10.0 percent of the thickener of Example 2, 10 percent diethylene glycol and 80 percent water. The presence of a surfactant and a reduced thickener content in liquid 1 results in a liquid having a substantially lower viscosity at 20 ° C than that observed for liquid 2, indicating that the apparent viscosity index of liquid 1 is higher than liquid 2.

Liquid 1 Liquid 2

Viscosity at 40 ° C, ηιπΛ ¹

550

550

Viscosity at 20 ° C, m / s ¹

000

500

PATENT CLAIMS

Claims (7)

Functional liquid, usable as a hydraulic fluid, lubricant, drilling fluid or coolant coolant, based on water, glycol and a thickener, characterized in that it contains 20 to 98% by weight of water, 1 to 80% by weight of glycol and 0, 25 to 25% by weight of a thickener prepared by reacting one mole of a monofunctional compound containing active hydrogen and having at least 10 carbon atoms with 20 to 400 moles of one or more alkylene oxides and subsequently reacting the resulting reaction product with diepoxide in an amount such that and the hydroxyl groups of the reaction product of the monofunctional compound with active hydrogen and alkylene oxides are between 0.2: 1 and 5: 1. CS 275 771 B5 Functional liquid according to claim 1, characterized in that it contains 35 to 95% by weight of water. Functional liquid according to claim 1, characterized in that it contains 20 to 60% by weight of glycol. A functional liquid according to claim 1, characterized in that it contains 2 to 10% by weight of a thickener. A functional liquid according to claim 1 or 3, characterized in that it further comprises 0.5 to 15% by weight of a non-ionic surfactant. Functional liquid according to claim 1, characterized in that it contains from 1 to 20% by weight of glycol and from 0.5 to 25% by weight of a thickener with an intrinsic viscosity of more than 20,000 mn @ ^-1 at 45 ° C. The functional liquid of claim 1, wherein the active hydrogen-containing compound is selected from C 1 to C ₂₀ monohydric alcohols and thiols, C 4. to C ₂ and C q alkylphenols | ₆ to _C20 aliphatic amines.