KR100961556B1 - Composition of corrosion inhibitor for water soluble oil-based metal working fluid - Google Patents

Abstract

 The present invention relates to a corrosion inhibitor composition for water-soluble metal working emulsion, more specifically, amino alkyl alkanol amine dicarboxylate, amino alkyl alkanolamine monocarboxylate, quaternary amine salt fatty acid dimethyl amine salt, water The present invention relates to a corrosion inhibitor composition for water-soluble metal processing emulsions, which is formed by mixing a predetermined ratio to improve lubricity, oxidation stability, anti-foaming property, and solubility in water in addition to excellent corrosion resistance.

Water Soluble, Metal Processing, Emulsion, Corrosion Inhibitor, Corrosion Resistance, Adsorption Characteristics, Polar Group, Corrosion Coating

Description

COMPOSITION OF CORROSION INHIBITOR FOR WATER SOLUBLE OIL-BASED METAL WORKING FLUID}

The present invention relates to a corrosion inhibitor composition added to water-soluble metalworking oils such as cutting oil, rolled oil and fresh oil.

In general, corrosion inhibitors function to prevent corrosion of metals by forming a corrosion coating by physicochemical adsorption reactions with metal surfaces, and are highly dependent on the polarity of the compound. However, corrosion of metals can be caused by accelerating desorption of the adsorbed corrosion coating under unstable or harsh conditions such as lack of emulsion stability, lack of lubricity, and lack of oxidation stability.

Conventional corrosion inhibitors for water-soluble metal covalents include amine bornates, amine carboxylates, polycarboxylic acids, fatty acid amides and organophosphate esters. (organic phosphorous acid esters), among them, amine carboxylate-based or fatty acid amide-based compounds are mostly used.

EP 04024857 is a composition consisting of fatty acid alkanolamides having 10 to 20 carbon atoms, alkyl alcohols having 2 to 14 carbon atoms, dicarboxylic acids having 10 to 12 carbon atoms, and the like. US Patent Publication No. 06-225605 discloses mono , Compositions comprising alkanol amine salts of di and triethanol amines with dicarboxylic acids, alkanol amines, chelating compounds, and the like, benzoic acid amides and ester derivatives (Korean Patent No. 053226), and US Pat. It is composed of 10 monocarboxylic acids, polycarboxylic acids having 4 to 10 carbon atoms, alkanol amines, etc., and these corrosion inhibitors have a single function of corrosion coating function by adsorption of polar groups. Low solubility in water due to hydrophobicity or hydrophilicity and low hydrophobicity, low adsorption properties due to polar group limitation There was a problem that the corrosion resistance decreases under the condition.

Accordingly, the present inventors have repeatedly studied the problems of conventional corrosion inhibitors for metal working emulsions, that is, increasing the solubility in water due to the increase of both hydrophilicity and hydrophobicity, and high adsorption characteristics due to the increase of polar groups. As a result, the present invention has been completed.

It is an object of the present invention to provide corrosion resistance properties of metal materials caused during processing of metal products through corrosion inhibitor compositions for water soluble metalworking emulsions and methods for their preparation.

In order to achieve the above object, the present invention provides a fatty acid dimethyl amine which is 1 to 50% by weight of amino alkyl alkanol amine dicarboxylate, 1 to 80% by weight of amino alkyl alkanolamine monocarboxylate, and a quaternary amine salt. The corrosion inhibitor composition for water-soluble metalworking emulsion which is formed by mixing 1 to 40% by weight of salt and 1 to 50% by weight of water is the main technical configuration of the invention.

Hereinafter, the technical configuration will be described in detail.

The amino alkyl alkanol amine dicarboxylate is synthesized by an amide reaction of amino alkyl alkanolamine with dicarboxylic acid, and is used in 1 to 50% by weight of the total composition, less than 1% by weight In the case of the corrosion resistance of the metal material, when used in excess of 50% by weight, there is a problem to be partially solidified, the amino alkyl alkanol amine dicarboxylate is 1 to 50% by weight of the total composition It is preferable to use.

The amino alkyl alkanolamine is any one or more selected from amino methyl ethanolamine, amino ethyl ethanolamine, amino propyl ethanolamine, and the dicarboxylic acid is succinic acid, glutaric acid, Adipic acid (phthalic acid), phthalic acid (phthalic acid), azelaic acid (azelaic acid), sebacic acid (sebacic acid) is any one or more selected from.

The amino alkyl alkanolamine monocarboxylate is synthesized by an amide reaction between amino alkyl alkanolamine and monocarboxylic acid, and is used in an amount of 1 to 80% by weight of the total composition. There is a problem in the corrosion resistance of the, and if it exceeds 80% by weight, there is a problem of some precipitation, it is preferable to use the amino alkyl alkanolamine monocarboxylate in 1 to 80% by weight of the total composition.

The amino alkyl alkanolamine is any one or more selected from amino methyl ethanolamine, amino ethyl ethanolamine, amino propyl ethanolamine, and the monocarboxylic acid has 4 to 10 carbon atoms, butanoic acid and penta. It is at least one selected from pentanoic acid, hexanoic acid, octanoic acid, nonanoic acid, and decanoic acid.

The fatty acid dimethyl amine salt, which is the quaternary amine salt, is synthesized by ionic reaction of fatty acid dialkylamine and acid, and is used in an amount of 1 to 40% by weight of the total composition. When it exceeds 40% by weight, there is a problem in the emulsification and viscosity of the solution, it is preferable to use the fatty acid dimethyl amine salt as the quaternary amine salt in an amount of 1 to 40% by weight of the total composition.

The fatty acid dimethyl amine is composed of lauric acid of 12 to 18 carbon atoms (lauric acid), myristic acid (myristic acid), palmitic acid (palmitic acid), stearic acid (stearic acid), oleic acid (oleic acid) At least one selected from dimethyl amine, myristyl dimethyl amine, palmityl dimethyl amine, stearyl dimethyl amine and oleyl dimethyl amine, and the acid is any one or more selected from acetic acid, boric acid and phosphoric acid.

The water is used to deionized (deionized), it is used in 1 to 50% by weight of the total composition, if less than 1% by weight has a problem in the viscosity and economic efficiency of the solution, if it exceeds 50% by weight Since there is a problem in pH and corrosion resistance, the water is preferably used in 1 to 50% by weight of the total composition.

1 to 50% by weight of amino alkyl alkanol amine dicarboxylate, 1 to 80% by weight of amino alkyl alkanolamine monocarboxylate, 1 to 40% by weight of fatty acid dimethyl amine salt which is a quaternary amine salt, The manufacturing process of the corrosion inhibitor composition for water-soluble metalworking emulsion made using 1 to 50% by weight of water will be described.

First, 1 mole of amino alkyl alkanolamine and 1 mole of dicarboxylic acid are added to a reactor and reacted for 1 to 5 hours at a reaction temperature of 120 to 180 ° C. under a nitrogen atmosphere to synthesize a reaction product of amino alkyl alkanolamine dicarboxylate. do.

At this time, if the reaction temperature is less than 120 ℃ amide reaction is not easy, if it exceeds 180 ℃ color change and thermal decomposition of the compound may occur, the reaction temperature is preferably maintained at 120 ~ 180 ℃ If the reaction time is less than 1 hour, the amide reaction is not easy. If the reaction time exceeds 5 hours, the compound cost is easily increased and the decomposition of the compound is easy. It is preferable to keep time for 1 to 5 hours.

Next, 1 mole of amino alkyl alkanolamine and 1 mole of monocarboxylic acid are added to the reactor, and reacted for 1 to 5 hours at a reaction temperature of 120 to 180 ° C. under a nitrogen atmosphere to synthesize a reaction product of amino ethyl ethanolamine monocarboxylate. .

At this time, if the reaction temperature is less than 120 ℃ amide reaction is not easy, if it exceeds 180 ℃ color change and thermal decomposition of the compound may occur, the reaction temperature is preferably maintained at 120 ~ 180 ℃ If the reaction time is less than 1 hour, the amide reaction is not easy, and if it exceeds 5 hours, the production cost increases and the decomposition of the compound is easy. Therefore, the reaction time at the reaction temperature of 120 to 180 ° C. It is preferable to keep it for 1 to 5 hours.

Next, 1 mole of fatty acid dimethylamine and 1 mole of acid are added to the reactor, and then reacted at a reaction temperature of 50 to 80 ° C. for 1 to 4 hours to synthesize fatty acid dimethyl amine salt.

At this time, if the reaction temperature is less than 50 ℃ covalent bond reaction is not easy, if it exceeds 80 ℃ may cause a reaction degradation due to volatilization of water, the reaction temperature is maintained at 50 ~ 80 ℃ It is preferable that the reaction time is less than 1 hour unreacted, and if it exceeds 4 hours, color change, manufacturing cost increase and may cause a change in the reactants, 50 ~ 80 ℃ of The reaction time at the reaction temperature is preferably maintained at 1 to 4 hours.

Subsequently, the fatty acid dimethyl amine salt, which is an amino alkyl alkanol amine dicarboxylate, amino alkyl alkanolamine monocarboxylate, or quaternary amine salt prepared by the above process, is mixed with water by the above mixing ratio. Prepare corrosion inhibitor for metal emulsion.

As described above, the corrosion inhibitor composition for water-soluble metal working emulsion according to the present invention increases the solubility in water by increasing the hydrophilicity and hydrophobic double-sided than the conventional corrosion inhibitor, and also has a high adsorption characteristics according to the increase of the polar group As a result, the corrosion resistance of the metal is very excellent. In particular, by adding a certain amount of the fatty acid dialkyl amine, a quaternary amine salt, hydrophilicity and hydrophobicity of both sides are increased, and the function of improving the lubricity and corrosion resistance due to the long-chain hydrophobic group of fatty acids is enhanced. In addition, it functions as a secondary function of improving lubricity, oxidation stability, anti-foaming, disinfection and solubility in water, and can be used as a coolant for metal products such as rolling oil, cutting oil, and fresh oil and as a coolant for metal products.

Let us look at the specific content of the above technical configuration through the embodiment.

Example 1

1 mole of amino ethyl ethanolamine and 1 mole of azelaic acid are added to the reactor and reacted for 3 hours at a reaction temperature of 160 ° C. under a nitrogen atmosphere to synthesize a reaction product of amino ethyl ethanolamine azelate (hereinafter referred to as AEEA). .

Example 2

1 mole of amino ethyl ethanolamine and 1 mole of octanoic acid were added to the reactor and reacted for 3 hours at a reaction temperature of 160 ° C. under a nitrogen atmosphere to obtain a reaction product of amino ethyl ethanolamine octanoate (hereinafter referred to as AEEO). Synthesize

Example 3

1 mole of lauryl dimethylamine and 1 mole of acetic acid are added to the reactor and reacted at a reaction temperature of 60 ° C. for 2 hours to synthesize a reaction product of lauryl dimethyl amine acetate (LDAA). .

Test Example 1

15 g of amino ethyl ethanolamine azelaic salt of Example 1, 40 g of amino ethyl ethanolamine octanoic salt of Example 2, 15 g of lauryl dimethyl amine acetate, a quaternary amine salt of Example 3, and 30 g of water, were synthesized. Corrosion resistance test of corrosion inhibitor for metal co-working agent was carried out by putting filter paper on petri dish according to ASTM D 4627-92, the test method for corrosion resistance of cast iron chips for water-soluble metal co-working agent, and then putting the cut iron chips of the gun into water-soluble emulsion prepared according to the concentration. After soaking, it was left to stand for 24 hours, and then evaluated for the presence of rust generated in cast iron chip specimens and compared with conventional commercially available corrosion inhibitors (Milacron, USA). In addition, it was analyzed using an FT-IR device to identify the synthesized reaction compound.

Reactants AEEA and AEEO obtained by the reaction was confirmed through the FT-IR instrument and the results are shown in FIG.

In Figure 1 (a) represents the AEEA, (b) it can be seen represents the structural formula of AEEO C = O peak at 1680cm ^-1 is, the NH peak appears at 1560cm ^-1.

Therefore, each of the reactants were kneaded according to the composition ratio to prepare 2%, 5% and 7% water-soluble emulsions to investigate their corrosion resistance. The results are shown in Table 1 and the existing commercially available corrosion inhibitors (Milachron, Product name: CIMCOOL Inhibitor 50 [preparative corrosion inhibitor for water-soluble metals], date of manufacture: September 9, 2007 Ingredients: Monoethanolamine (CAS # 141-43-5) 30-60%, USA.

According to the concentration change Corrosion resistance Corrosion inhibitor One 2 3 4 5 6 Comparative example Composition ratio (wt%) AEEA 10 20 10 20 10 20 AEEO 60 50 50 40 40 30 LDAA - - 10 10 20 20 water 30 30 30 30 30 30 Corrosion Resistance According to Concentration Ratio 2% ○ ○ ○ × × × ○ 5% ○ ○ × × × × ○ 7% × × × × × × ×

O: no corrosion, X: no corrosion

As shown in Table 1, the corrosion inhibitor for the water-soluble metal co-working agent of the present invention prepared according to the change in concentration shows superior corrosion resistance than the existing products.

1 is a graph of the FT-IR spectrum of the reactants according to the reaction of the present invention.

Claims (4)

1 to 50% by weight of amino alkyl alkanol amine dicarboxylate, 1 to 80% by weight of amino alkyl alkanolamine monocarboxylate, 1 to 40% by weight of fatty acid dimethyl amine salt which is a quaternary amine salt, Corrosion inhibitor composition for water-soluble metalworking emulsion, characterized in that the composition is composed of 1 to 50% by weight of water. The method of claim 1, wherein the amino alkyl alkanol amine dicarboxylate is synthesized by an amide reaction of amino alkyl alkanolamine with dicarboxylic acid, The amino alkyl alkanolamine is any one or more selected from amino methyl ethanolamine, amino ethyl ethanolamine, amino propyl ethanolamine, and the dicarboxylic acid is succinic acid, glutaric acid, An anticorrosive composition for water-soluble metalworking emulsion, characterized in that at least one selected from adipic acid, phthalic acid, phthalic acid, azelaic acid, and sebacic acid. The method of claim 1, wherein the amino alkyl alkanolamine monocarboxylate is synthesized by an amide reaction of amino alkyl alkanolamine with a monocarboxylic acid, The amino alkyl alkanolamine is any one or more selected from amino methyl ethanolamine, amino ethyl ethanolamine, amino propyl ethanolamine, and the monocarboxylic acid has 4 to 10 carbon atoms butanoic acid and pentano. Water-soluble metal, characterized in that any one or more selected from pentanoic acid, hexanoic acid, octanoic acid, nonanoic acid, decanoic acid Anticorrosive composition for processed emulsions. The fatty acid dialkyl amine salt according to claim 1, which is a quaternary amine salt, is synthesized by ionic reaction of fatty acid dialkylamine with an acid, The fatty acid dimethyl amine is composed of lauric acid of 12 to 18 carbon atoms (lauric acid), myristic acid (myristic acid), palmitic acid (palmitic acid), stearic acid (stearic acid), oleic acid (oleic acid) Water soluble, characterized in that any one or more selected from dimethyl amine, myristyl dimethyl amine, palmityl dimethyl amine, stearyl dimethyl amine, oleyl dimethyl amine, the acid is any one or more selected from acetic acid, boric acid, phosphoric acid Corrosion inhibitor composition for metal working emulsion.

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