GB2194782A

GB2194782A - Additives for aqueous functional fluids

Info

Publication number: GB2194782A
Application number: GB08527680A
Authority: GB
Inventors: Geoffrey Graham
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1985-11-09
Filing date: 1985-11-09
Publication date: 1988-03-16
Also published as: GB8527680D0; GB2194782B

Abstract

An additive combination which imparts excellent corrosion-inhibiting and anti-wear properties to an aqueous functional fluid, comprises: (A) a mixture of monobutyl phosphate and dibutyl phosphate; and (B) a compound having the formula I: <IMAGE> in which Z is a C1-C11 alkylene group, X is hydrogen, an alkali metal, mono-, di- or triethanolamine, R1 and R2 are hydrogen or methyl, and R3 is a group -NR4R5 in which R4 is C1-C12 alkyl or -Z-COOX wherein Z and X have their previous significance and R5 is hydrogen or C1-C12 alkyl; the ratio by weight of component (A) to component (B) being at least 5:1.

Description

SPECIFICATION Additives for aqueous functional fluids The present invention relates to additives for aqueous functional fluids.

Various additives are usually added to aqueous functional fluids in order to improve their use properties. For example, so-called high-pressure and anti-wear additives are added to aqueous functional fluids which require a high load-bearing capacity, in order that the fluid can transfer large forces. Effective anti-wear additives greatly reduce the appearances of wear which would otherwise occur. Moreover, when corrosive agents e.g. oxygen and moisture act simultaneously on a metal surface, corrosion can occur. Accordingly, in these circumstances, corrosion inhibitors are added to inhibit the access of such agents to the metal surfaces. Oxidation reactions in a functional fluid, set up by atmospheric oxygen and increased at elevated temperature, can be suppressed by adding an antioxidant.

There is a constant search for additive packages which will provide improved stabilisation of aqueous functional fluids and metal surfaces in contact with such fluids.

One well-known class of general corrosion inhibitors are alkyl phosphates e.g. SANDOCORIN 8000 (SANDOZ A.G.) which is an approximately 25% aqueous solution of monobutyl phosphate and dibutyl phosphate, neutralised with caustic soda. These alkyl phosphates, however, do not pass one of the basic corrosion-inhibitor tests, namely Corrosion Test IP 287, which is used to evaluate corrosion inhibitors for aqueous functional fluids. Moreover, there are no disclosures showing that such alkyl phosphates have ever been used, or recommended for use as an extreme pressure/antiwear additive for functional fluids.

In European Patent Specification No. 46139 there are described certain triazine compounds, having excellent corrosion-inhibiting properties for ferrous metals and having the formula

in which Z is a C,-C" alkylene group, X is hydrogen, an alkali metal, mono-, di- or triethanolamine, R, and R2 are hydrogen or methyl and R3 is a group -NR4R5 in which R4 is C,-C,2 alkyl or -Z-COOX in which Z and X have their previous significance, and R5 is hydrogen or C1-C12 alkyl.

The triazine compounds of formula I, while they pass readily the IP 287 corrosion-inhibitor test, exhibit very poor antiwear properties in standard antiwear tests.

Surprisingly, we have found that a combination of an optionally neutralised alkyl phosphate and a triazine compound of formula I, in specified relative proportions, provides an additive package which imparts to an aqueous functional fluid effective corrosion inhibition combined with good antiwear properties.

Accordingly, the present invention provides an additive combination for an aqeous functional fluid, the combination comprising: A) at least one optionally neutralised C1-C12 alkyl phosphate; and B) at least one compound having the formula I, as hereinbefore defined, the ratio by weight of component A) to component B), excluding the cation X, being at least 5 to 1, preferably from 5 to 12.

Component A) of the additive combination of the present invention may be any optionally neutralised C,-C,2 alkyl phosphate, or mixture thereof, but is preferably any commercially available mixture of C,-C,2 mono-alkyl- and di-alkyl phosphates, eg methyl dihydrogen phosphate, dimethyl hydrogen phosphate, n-butyl dihydrogen phosphate, n-butyl dihydrogen phosphate, di-nbutyl hydrogen phosphate, n-dodecyl dihydrogen phosphate, di-n-dodecyl hydrogen phosphate, optionaly in the form of their alkali metal salts, especially the commercial product sold as SANDOCORIN 8000 which is an approximately 25% aqueous solution of monobutyl phosphate and dibutyl phosphate which has been neutralised with caustic soda.

With respect to the compounds of formula 1, Z may be methylene, 1,2-ethylene, 1,2propylene, 1,3-propylene, 1 ,4-butylene, 1,1 -dimethyl- 1 ,2ethylene, 1 5-pentylene, 1 ,6-hexylene, 1,8-octylene, 1,10-decylene or 1,1 1 -undecylene. Preferably Z contains 1-5 C-atoms, especially 1-3 C-atoms.

When X is an alkali metal, it may be sodium, potassium or lithium. When X is an alkaline earth metal it may be calcium or magnesium. Examples of ammonium groups X are the proto nated residues of methylamine, ispropylamine, dodecylamine, dibutylamine, triethylamine, tributylamine, ethanolamine, diethanolamine, dipropanolamine, or triethanolamine. Preferably, X is hydrogen, alkali metal or mono-, di- or triethanolamine.

R3 is preferably a group -NR4R5 in which R4 is -Z-COOX or C1-C8 alkyl and R5 is hydrogen, methyl or ethyl.

The additive combination of the invention may be produced as a dry powder by dry blending solid components a) and b) or, preferably, as an aqueous solution by dissolving in water components a) and b) in the defined proportions by weight.

Examples of specific compounds of formula I are as follows: 2,4,6-Tris(5'-carboxypentylamino)- 1 ,3,5-triazine, 2,4,6-Tris(carboxymethylamino)- 1 3,5-triazine, 2,4,6-Tris(3'-carboxypropylamino)- 1,3,5-triazine, 2,4,6-Tris(2'-carboxyethylamino)- 1,3,5-triazine, 2,4,6-Tris(4'-carboxybutylamino)-1 ,3,5-triazine, 2,4,6-Tris(11 '-carboxyundecylamino)- 1,3,5-triazine, 2,4,6-Tris(5'-carboxypentyl-N-methylamino)- 1,3,5-triazine, 2,4,6-Tris(carboxymethyl-N-methylamino)- 1 3,5-triazine, 2,4,6-Tris(3'-carboxypropyl-N-methylamino)- 1,3 ,5-triazine, 2,4-Bis(5'-carboxypentylamino)-6-n-octylamino- 1,3,5-triazine, 2,4-Bis(5'-carboxypentylamino)-6-diethylamino- 1,3,5-triazine, 2,4-Bis(2'-carboxyethylamino)-6-n-octylamino- 1,3,5-triazine, 2,4-Bis(2'-carboxyethylamino)-6-diethylamino- 1,3 5-triazine, 2,4-Bis(2'-carboxyethylamino)-6-butylamino- 1,3,5-triazine, 2,4-Bis(2'-carboxyethylamino)-6-ethylamino- 1,3,5-triazine 2,4-Bis(3'-carboxypropylamino)-6-ethylamino-1 1,3,5-triazine 2,4-Bis(3'-carboxypropylamino)-6-n-octylamino-1 1,3,5-triazine 2,4-Bis(3'-carboxypropylamino)-6-n-propylamino-1 1,3,5-triazine 2,4-Bis(carboxymethylamino)-6-n-octylamino- 1,3,5-triazine 2,4-Bis(carboxymethylamino)-6-dodecylamino-1 1,3,5-triazine 2,4-Bis(5'-carboxypentyl-N-methylamino)-6-ethylamino-1 3,5-triazine 2,4-Bis(3'-carboxypropyl-N-methylamino)-6-n-octylamino-1 3,5-triazine 2,4-Bis(carboxymethyl-N-methylamino)-6-n-octylamino-1 1,3,5-triazine 2,4-Bis(2'-carboxyethyl-N-methylamino)-6-n-octy [ amino- 1,3,5-triazine 2,4-Bis(5'-carboxypentylamino)-6-(2"-carboxyethylamino)-1 3,5-triazine 2,4-Bis(5'-carboxypentylamino)-6-(carboxymethylamino)-1 3,5-triazine 2,4-Bis(3'-carboxypropylamino)-6-(2"-carboxyethylamino)-1 1,3,5-triazine 2,4-Bis(2'-carboxyethylamino)-6-(5"-carboxypentylamino)- 1,3,5-triazine 2,4-Bis(3'-carboxypropylamino)-6-(5"-carboxypentylamino)-1 1,3,5-triazine The compounds of formula I are not new.These compounds and their production are described e.g. in Zhurnal Analiticheskoi Khimii 15, 419-423 (1960), in DE-OS 1935010, in DE-OS 2819796, in US Patent Specification 3697520 and in J. Prakt Chemie 23 173-85 (1963).

The additive combination of the invention is readily soluble in aqueous functional fluids.

Accordingly, the present invention also provides an aqueous functional fluid containing 0.001 to 5% by weight, based on total weight of the functional fluid, of an additive combination of this invention.

The aqueous functional fluid base of the compositions of the invention may be e.g. aqueous machining fluid formulations (e.g. for use in boring, milling, reaming, turning, cutting, sawing, grinding, broaching and thread-cutting operations or in non-cutting shaping in drawing or rolling operations); aqueous glycol antifreeze systems; or water/glycol hydraulic fluids.

In the aqueous compositions of the invention in which the aqueous system component is an aqueous machining fluid formulation, such formulation may be a water dilutable cutting or grinding fluid such as: a) Aqueous concentrates of the additive combination of the invention, used at dilutions of 1:50 to 1#1000, which are usually employed as grinding fluids; b) Polyglycols containing the additive combination of the invention which are used at dilutions of 1:20 to 1:40 for cutting operations and 1:60 to 1: :80 for grinding; c) Semi-synthetic cutting fluids similar to b) but containing in addition 10 to 25% oil with sufficient emulsifier to render the water diluted product translucent; d) An emuisifiable mineral oil concentrate containing, for example, an addition to the additive combination of the invention, emulsifiers, biocides, antifoaming agents, coupling agents etc; they are generally diluted from 1:10 to 1:50 with water to a white opaque emulsion; e) A product similar to d) containing less oil and more emulsifier which on dilution to the range 1:50 to 1:1000 gives a translucent emulsion for cutting or grinding operations.

The additive combination of the invention may be used as sole additive package or in admixture with other additives for aqueous functional fluids e.g. known corrosion inhibitors and, for the machining fluids, known extreme-pressure additive.

Examples of further corrosion inhibitors which may be present in the aqueous functional fluids of the present invention include the following groups: a) Organic acids, their esters or ammonium, amine, alkanolamine and metal salts, for example, benzoic acid, ptert.buWl benzoic acid, disodium sebacate, triethanolamine laurate, isononanoic acid, triethanolamine salt of (ptoluene sulphonamido caproic acid), sodium N lauroyl sarcosinate nonyl phenoxy acetic acid, or boric acid, boric acid esters include boric acid and their amine salts.

b) Nitrogen containing materials such as the following types: fatty acid alkanolamides; imidazolines, for example 1-hydroxy-ethyl-2-oleyl-imidazoline; oxazolines; triazoles for example benzotriazoles; and inorganic salts, for example sodium nitrite and nitrate; c) Phosphorus-containing materials such as the following types: amine phosphates, phosphonic acids or inorganic salts, for example sodium dihydrogen phosphate; d) Sulphur containing compounds such as the following types: sodium, calcium or barium petroleum sulphonates, or heterocyclics for example sodium mercaptobenzothiazole.

Examples of further extreme pressure additives which may be present in the fluids of the present invention include sulphur and/or phosphorus and/or halogen containing materials, for instance sulphurised sperm oil, sulphurised fats, tritolyl phosphate, chlorinated paraffins or ethoxylated phosphate esters.

The following Examples further illustrate the present invention. Parts and percentages are by weight unless otherwise stated.

Examples 1 and 2 The corrosion resistance and anti-wear properties of 1:1 ethylene glycol/water mixtures containing various additive packages, were determined.

The corrosion resistance performances were assessed by the following procedure, which is a modification of the Institute of Petroleum Test 287.

A 1% solution of the compound or additive mixture under test is prepared and contains sufficient triethanolamine (TEA) that the solution has a pH value of 8.5.

This solution is further diluted by a factor of 2,4,8 or 16 and each of the solutions so obtained is contacted with cast iron chips-placed on a filter paper according to the method set forth in the 1P287 Test Procedure.

The visual assessment of the condition of the filter paper after exposure is in accordance with the following guidelines: degree of rusting rating no rusting 0 < 5 small specks T(trace) t100/o area rusted M(moderate) > 10% area rusted S(severe) The results obtained are set out in the following Table I.

The antiwear properties were determined by the Falex procedure using, as base fluid, the 1:1 ethylene glycol mixture but containing sufficient triethanolamine that the fluid has a pH value of 8.5+0.1, plus the additive under test.

The additives tested were: A) SANDOCORIN 8000 (Product A) which is a 25% by weight solution of the sodium salt of mixed mono- and di-butyl phosphates; and B) an additive combination of the invention (Product B) comprising 1 part by weight of 2,4,6-tris (5-carboxypentylamino)-1 3,5-triazine, 2 parts by weight of triethanolamine and 1 part by weight of water.

Table I

. Product A Product B Weight Falex Test IP 287 Example 25% wt % by wt ratio Total wt loss Corrosion Test solution A:B (mg) (Rating) l l - O 0.175 - 100 (Fail) O Pass 1 2.0 0.175 11.4:1 0.7 (Pass) O Pass 2 1.0 0.175 5.7:1 4.5 (Pass) O 0 Pass 0.5 0.175 2.85: :1 48 (Fail) O Pass - 0.25 0.175 1.43:1 73 (Fail) - 1.0 0 - 2.2 (Pass) S - 0.5 0 - 54 (Fail) S The results demonstrate that additive combinations of the invention impart adequate corrosion/antiwear properties to an aqueous functional fluid. By contrast, additive combinations which are similar to, but fall outside the definition of the additive combinations of the invention, fail this test.

Claims

1. An additive combination for an aqueous functional fluid, the combination comprising: A) at least one optionally neutralised C,-C,2 alkyl phosphate; and B) at least one compound having the formula l:

in which Z is a C,-C" alkylene group, X is hydrogen, an alkali metal, mono-, di- or triethanolamine, R, and R2 are hydrogen or methyl, and R3 is a group -NR4R5 in which R4 is C,-C,2 alkyl or -Z-COOX wherein Z and X have their previous significance and R5 is hydrogen or C,-C12 alkyl; the ratio by weight of component A) to component B) excluding the cation X being at least 5.0 to 3:1.

2. Additive combination according to claim 1 wherein the ratio by weight of component A) to component B) is within the range of from 5 to 12.

3. Additive combination according to claim 1 or 2 wherein component A) is a mixture of C1-C12 alkyl- and di-alkyl phosphates, optionally in the form of their alkali metal salts.

4. Additive combination according to claim 3 wherein component A) is an approximately 25% aqueous solution of monobutyl phosphate and dibutyl phosphate, which has been neutralised with caustic soda.

5. Additive combination according to claim 1 wherein, in the compound of formula I, Z contains 1 to 5 C-atoms.

6. Additive combination according to claim 5 wherein Z contains 1 to 3 C-atoms.

7. Additive combination according to claim 1 wherein, in the compound of formula I, X is hydrogen, an alkali metal or mono-, di- or tri-ethanolamine.

8. Additive combination according to claim 1 wherein R3 is a group -NR4R5 in which R4 is -Z-COOX in which Z and X are as defined in claim 1, or R4 is C1-C8 alkyl, and R5 is hydrogen, methyl or ethyl.

9. Additive combination according to claim 1 wherein component B) is 2,4,6-tris(5'-carboxy pentylamino)-1 ,3,5-triazine.

10. An aqueous functional fluid composition containing 0.001 to 5% by weight, based on the total weight of the functional fluid, of an additive combination as defined in claim 1.

11. Functional fluid composition according to claim 10 wherein the functional fluid is an aqueous machining fluid, an aqueous glycol anti-freeze or a water/glycol hydraulic fluid.

12. Functional fluid composition according to claim 11 wherein the functional fluid is a waterdilutable cutting or grinding fluid.

13. Functional fluid composition according to claim 10 in which other known additives for functional fluids are present.