JPH06116203A - New polycarboxylic acid, its salt and their production - Google Patents

Abstract

PURPOSE:To provide a new polycarboxylic acid having excellent water-solubility, biodegradability and dispersibility and useful as a unique and epoch-making chelating agent. CONSTITUTION:The compound of formula I [P, Q, S and T are (CH2)n-COOM, 1-5C alkyl or H provided that at least one of P to T is (CH2)n-COOM; M is H, alkali metal, alkaline earth metal, ammonium, mono, di or tri(2-3C alkanol) ammonium, 1-5C alkyl-substituted ammonium or basic amino acid residue; (n) is 0-5; Z is COOM, CN or group of formula II; R<1> is H or 1-22C alkyl] or its salt. This compound can be produced by reacting a compound of formula III [P', Q', S' and T' are (CH2)n-COOR<2> (R<2> is 1-6C alkyl), 1-5C alkyl or H provided that at least one of P' to T' is (CH2)n-COOR<2>] with a compound of formula IV (Z' is COOR<2>, CN or group of formula II) in the presence of a base and hydrolyzing the obtained compound of formula V.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a novel polycarboxylic acid,
More particularly, the present invention relates to a polycarboxylic acid useful as a water-soluble metal dispersant or a chelating agent for household and industry, a salt thereof, and a method for producing the same.

[0002]

BACKGROUND OF THE INVENTION Chelating agents are used in various fields for the purpose of sequestering metal ions mainly by removing calcium ions and magnesium ions in hard water and removing their harmful poisons. ing.

In the fiber / dyeing industry, natural fibers are mixed with metals derived from insecticide / sterilization, and synthetic fibers are mixed with metals from equipment. Therefore, a chelating agent is used to prevent these metals from binding to the soap and depositing in the fibers in the washing step, but preventing this. Also, in the bleaching process, bleaching is performed using hydrogen peroxide, etc., but a trace amount of metal ions (especially iron, copper, manganese) causes decomposition of the bleaching agent, so a chelating agent is added here to prevent this. is doing. Further, in the dyeing process, a trace metal that causes color change and color unevenness is trapped by a chelating agent.

In the metal / plating industry, a chelating agent is used for alkali cleaning in order to clean the metal surface. Also,
When dipping plating is called copper plating, copper (I
The use of (I) -chelating agent has the effect of binding iron (II) ions generated by the reaction, maintaining a dissolved state, and enabling fine and uniform plating.

[0005] In household use, various detergents are used to remove dirt from fabrics, dishes, and the body. The surfactant acting as this reacts with calcium or magnesium in tap water to wash it. to disturb. Therefore, a detergent is usually blended with a builder as a chelating agent to efficiently disperse calcium and magnesium and bring out the performance of a surfactant.

Conventionally, sodium tripolyphosphate (STPP) and ethylenediaminetetraacetate (EDTA) have been used as these chelating agents, but STPP is in the direction of eutrophication in lake water, and EDTA is toxic because of its toxicity. Thus, alternatives include organic nitrogen-containing compounds, carbonates, zeolites and acrylic acid oligomers. However, each of these substances has the following problems. It is feared that the nitrogen-containing compound is inferior in biodegradability.
Carbonates also produce insoluble precipitates of insoluble calcium carbonate. Zeolites are widely used, but they are water-insoluble substances, and if they are used in excess, they have the drawback of clogging sewer pipes and the like. Further, the acrylic acid oligomer has a problem of low biodegradability. Therefore, it is required to develop a chelating agent which is water-soluble, has excellent biodegradability and safety, and has a high metal dispersing ability.

[0007]

As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a specific novel polycarboxylic acid or a salt thereof can greatly achieve the above-mentioned object. Completed the invention. That is, the present invention provides a polycarboxylic acid represented by the general formula (I) or a salt thereof and a method for producing the same.

[0008]

[Chemical 7]

[Wherein P, Q, S, and T are respectively-(CH ₂ ) _n
A -COOM group, an alkyl group or a hydrogen atom of 1 to 5 carbon atoms, P, Q, S, at least one among T is - (CH _{2) n} -COOM
It is a base. M is a hydrogen ion, an alkali metal ion, an alkaline earth metal ion, an ammonium ion, a mono-, di-, or trialkanol ammonium ion having an alkanol group having 2 to 3 carbon atoms, an alkyl-substituted ammonium ion having 1 to 5 carbon atoms, Alternatively, it represents a basic amino acid group. n shows 0 or the number of 1-5. Z is a --COOM group, --CN
Group, or

[0010]

[Chemical 8]

Either of the above is shown. R ¹ represents a hydrogen atom or an alkyl group having 1 to 22 carbon atoms. ] In the general formula (I)
P, Q, S, T, respectively, - (CH _{2) n} -COOM group, 1 carbon atoms
5 represents an alkyl group or a hydrogen atom, preferably -CO
It is an OM group or a hydrogen atom. Incidentally, P, Q, S, at least one among T is - (CH ₂₎ must be _n -COOM group. Examples of the compound represented by the general formula (I) include the compounds shown below.

[0012]

[Chemical 9]

The polycarboxylic acid represented by the general formula (I) or a salt thereof provided by the present invention is produced by the following method. That is, the general formula (II)

[0014]

[Chemical 10]

(Where P ', Q', S ', and T'are-(C
H ₂ ) _n —COOR ² group, an alkyl group having 1 to 5 carbon atoms or a hydrogen atom, and at least one of P ′, Q ′, S ′ and T ′ is — (C
A H _{²⁾ n} -COOR ₂ group. Wherein R ² represents an alkyl group having 1 to 6 carbon atoms, n represents the same meaning as defined above. ) And a compound represented by the general formula (III)

[0016]

[Chemical 11]

(Wherein R ¹ and R ² have the above-mentioned meanings, and Z ′
Is a -COOR ² group, a -CN group, or

[0018]

[Chemical 12]

Either one of the above is shown. ) And a compound represented by the formula (IV)

[0020]

[Chemical 13]

(Wherein P ', Q', S ', T', R ¹ and Z'have the above-mentioned meanings), and then hydrolyzed with an alkali, if necessary. The desired salt may be exchanged.

Examples of the compound represented by the general formula (II) include diethyl epoxysuccinate, ethyl glycidate, and 2
-Methyl-glycidate ethyl, itaconic acid epoxide diethyl ester, citraconic acid epoxide diethyl ester, crotonic acid epoxide diethyl ester and the like. These epoxy compounds are obtained by oxidizing the double bond of the corresponding unsaturated carboxylic acid with hydrogen peroxide followed by esterification. It is effective to use phosphotungstic acid, phosphomolybdic acid or the like as the oxidation catalyst. This synthetic method is known, and J. Org. Chem.,
50, 1979-1982 (1985). A known method may be used for esterification.

Examples of the compound represented by the general formula (III) include compounds having active hydrogen such as dimethyl malonate, diethyl malonate, methyl cyanoacetate, ethyl cyanoacetate, methyl acetoacetate and ethyl acetoacetate. .

Further, this reaction will be described in detail. By reacting a compound represented by the general formula (II) (hereinafter abbreviated as epoxycarboxylic acid ester (II)) with a compound represented by the general formula (III) (hereinafter abbreviated as active hydrogen-containing compound (III)) A compound represented by the general formula (IV) (hereinafter referred to as compound (IV)
In order to obtain a carbanion by extracting a hydrogen ion from the active hydrogen-containing compound (III), a base for this purpose is sodium ethylate (C ₂ H ₅ ONa) or potassium ethylate. acrylate (C ₂ H ₅ OK), sodium methylate (CH ₃ ONa), potassium methylate (CH ₃ O
K), sodium hydride (NaH), potassium hydride (KH),
Examples thereof include sodium and potassium. The amount of the base may be a catalytic amount, but is preferably equimolar to the active hydrogen-containing compound (III) in order to obtain a normal reaction rate. If the reaction temperature exceeds 60 ° C, a side reaction product is generated,
C. or less is preferable, and more preferably 40 to 60.degree.
As the solvent, alcohols such as methanol, ethanol, propanol, butanol, diethyl ether,
Ethers such as tetrahydrofuran and 1,4-dioxane, amides such as dimethylformamide and dimethylacetamide, and dimethylsulfoxide or dimethylimidazolidinone may be used. The solvent is preferably dehydrated in order to keep the activity of the base. Epoxycarboxylic acid ester (II) and active hydrogen-containing compound
The molar ratio with (III) is 1:10 to 10: 1, preferably 1: 2.
˜2: 1, more preferably 1: 1.2 to 1.2: 1.

For the hydrolysis of the obtained compound (IV), a conventionally known method may be used. That is, sodium hydroxide,
Alkali such as potassium hydroxide is added to the ester group at 1
˜2 equivalents may be used to heat at 40 ° C. to 100 ° C., preferably 60 to 95 ° C. for several hours. At this time, water-methanol, water-ethanol, water-propanol, water-butanol or the like may be used as the solvent. The hydrolyzate thus obtained may be used as it is as an alkali salt, or if necessary, may be subjected to counterion exchange with a desired salt.

The novel polycarboxylic acid represented by the above general formula (I) or a salt thereof of the present invention is not only a metal dispersant or an industrial chelating agent, but also a hard surface, body, clothing used at home. It can also be used as a detergent builder for. At that time, other components to be blended are not particularly limited as long as they are generally used in detergents, and, of course, they can be used in combination with conventional chelating agents.

[0027]

Industrial Applicability According to the present invention, it is possible to provide a polycarboxylic acid or a salt thereof which is excellent in water solubility, biodegradability and dispersibility and is useful as an unprecedented epoch-making chelating agent.

[0028]

EXAMPLES The present invention is described in detail below with reference to examples, but the present invention is not limited to these examples.

Example 1 Malonic acid with epoxy succinic acid
Additive synthesis

[0030]

[Chemical 14]

(A) Esterification of epoxysuccinic acid

[0032]

[Chemical 15]

25.3 g (0.189 mol) of trans-epoxysuccinic acid, 523.3 g (11.36 mol) of ethanol, and 13 g of strongly acidic ion exchange resin NAFION (NR-50) (manufactured by Du Pont) were charged, and the mixture was heated at 80 ° C. for 16 hours. Esterification was performed. The strongly acidic ion exchange resin was removed by filtration, and ethanol was distilled off with a rotary evaporator to obtain 33.4 g of trans-epoxysuccinic acid diethyl ester. Yield 92.5%. 92.5% purity by GPC. As shown in Table 1, the analytical values were in good agreement with the theoretical values.

[0034]

[Table 1]

IR (cm ^-1 ): 2986, 2944, 1746, 1473, 14
49, 1398, 1374, 1233, 1197, 1098, 1029, 966, 900 ¹ H-NMR (ppm): 4.3 (4H), 3.7 (2H), 1.3 (6H) (b) Diethyl epoxysuccinate diethyl malonate Addition to

[0036]

[Chemical 16]

22.42 g (0.14 mol) of diethyl malonate,
9.53 g (0.14 mol) of sodium ethylate and 250 g of ethanol were charged, and 26.35 g (0.14 mol) of diethyl epoxysuccinate was added dropwise thereto at 40 ° C. for 2 hours. After aging at 40 ° C. for 3 hours, 8.41 g (0.14 mol) of acetic acid was added to complete the reaction. After the ethanol was distilled off by a rotary evaporator, 60 g of water was added, and this was extracted once with 80 ml of ether and twice with 40 ml. The ether layers were combined and washed 3 times with 50 ml of 5% aqueous sodium chloride solution. It was dried over anhydrous sodium sulfate and the ether was distilled off. The concentrate was distilled to give 11.91 g of the adduct of diethyl epoxysuccinate with diethyl malonate. Yield 28.1
%. Saponification value (KOHmg / g) is 723.6g, theoretical value
It was in good agreement with (742.5).

IR (cm ^-1 ): 2992, 2944, 1803, 1743, 14
73, 1452, 1377, 1197, 1155, 1095, 1023, 975, 90
0, 858 ¹ H-NMR (ppm): 4.3 (7H), 3.9 (1H), 3.6 (1H), 1.3 (9
H) (c) hydrolysis

[0039]

[Chemical 17]

Addition product of diethyl epoxysuccinate to diethyl malonate 9.67 g (32 mmol), sodium hydroxide 5.99 g (150 mmol), ethanol 150 g, and water 150.
g was charged and the hydrolysis reaction was carried out for 5 hours under reflux. The reaction solution was cooled, 2.52 g (25 mmol) of concentrated hydrochloric acid was added, and the pH was adjusted to 9
I chose After concentrating with a rotary evaporator, it was vacuum dried to obtain 12.99 g of the desired product in powder form. Yield 100
%. As a result of the analysis, it contained sodium chloride 10.7% and water 6.4%. The saponification value and total amine value were in good agreement with the theoretical values as shown in Table 2.

[0041]

[Table 2]

In addition, it was confirmed that there was a single peak in GPC. IR (cm ^-1 ): 3460, 1593, 1404, 1338, 1095 ¹ H-NMR (ppm): 4.2 (1H), 3.6 (1H), 3.2 (1H) Test Example Ca of the compound obtained in Example 1 The ion trapping ability and the Ca ion stability constant pK Ca ²⁺ were investigated by the methods described below.
For comparison, the zeolite used as a chelating agent in the past was also examined for Ca ion trapping ability and Ca ion stability constant pK Ca ²⁺ . The results are shown in Table 3.

Method for measuring capture ability for calcium ion
And chelate stability constant measurement methods All solutions were prepared using the following buffer solutions. _{Buffer; 0.1M NH 4 Cl-NH 4} OH buffer (pH 10) (1) Creating a calibration curve standard calcium ion solution to create a calibration curve showing the relationship between the logarithm and the potential of the calcium ion concentration such shown in FIG. 1 To create.

(2) Measurement of calcium ion-capturing ability A sample of 0.1 g is weighed in a 100 ml volumetric flask, and the volume is adjusted with the above buffer solution. A CaCl ₂ solution (pH 10) equivalent to 20,000 ppm (calculated as CaCO ₃ ) is added dropwise to this from a buret (a blank is also measured). CaCl ₂ solution is dropped.
Add 0.1 to 0.2 ml each, read the potential at that time, and find the calcium ion concentration from the calibration curve in FIG.
The calcium ion concentration at the dropping amount A of the CaCl ₂ solution in FIG. 2 is the calcium ion trapping ability of the sample.

(3) Calculation of calcium ion chelate stability constant The calcium ion chelate stability constant (pK Ca ²⁺ ) is Ca
^Use the result of ²⁺ capture ability measurement. It is calculated as forming a 1: 1 complex when equimolar calcium is added to the sample. The stability constant of the complex can be calculated according to the following formula.

[0046]

[Equation 1]

[0047]

[Table 3]

[Brief description of drawings]

FIG. 1 is a calibration curve showing the relationship between the logarithm of calcium ion concentration and the potential.

[Fig. 2] CaCl during measurement of calcium ion-capturing ability
₂ is a graph showing the relationship between the drop amount of _two solutions and the calcium ion concentration.

Claims (3)

[Claims] 1. A novel polycarboxylic acid represented by the general formula (I) or a salt thereof. [Chemical 1] Wherein, P, Q, S, T, respectively, - (CH _{2) n} -COOM group, an alkyl group or a hydrogen atom of 1 to 5 carbon atoms, P, Q, S,
At least one among the T is - (CH _{2) n} -COOM group. M
Is a hydrogen ion, an alkali metal ion, an alkaline earth metal ion, an ammonium ion, a mono-, di-, or trialkanol ammonium ion having an alkanol group having 2 to 3 carbon atoms, an alkyl-substituted ammonium ion having 1 to 5 carbon atoms, or Indicates a basic amino acid group. n shows 0 or the number of 1-5. Z is -COOM group, -CN group, or Indicates either R ¹ represents a hydrogen atom or an alkyl group having 1 to 22 carbon atoms. ] 2. P, Q, S and T each represent a --COOM group or a hydrogen atom, and at least one of P, Q, S and T is --CO.
The polycarboxylic acid or a salt thereof according to claim 1, which is an OM group (M has the above-mentioned meaning). 3. A compound represented by the general formula (II): (Wherein, P ', Q', S ', T' , _{respectively, - (CH 2) n -COOR} 2
A group, an alkyl group having 1 to 5 carbon atoms or a hydrogen atom,
P ', Q', S ' , T' at least 1 in the - (CH _{2) n} -COOR
^{There are two} . Wherein R ² represents an alkyl group having 1 to 6 carbon atoms, n represents the same meaning as defined above. ) A compound represented by
General formula (III): (In the formula, R ¹ and R ² have the aforementioned meanings, and Z ′ represents —COOR.
² groups, -CN group, or Indicates either ) Is reacted with a compound represented by the formula (1) in the presence of a base to give a compound of the general formula (IV): (In the formula, P ′, Q ′, S ′, T ′, R ¹ and Z ′ have the above-mentioned meanings), and then the compound is hydrolyzed with an alkali to obtain a desired compound. The method for producing a polycarboxylic acid represented by the general formula (I) or a salt thereof according to claim 1, wherein the polycarboxylic acid is replaced with a salt.