JPH09309928A - Acrylic polymer, biodegradable builder and detergent composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an economically profitable builder having excellent chelating capacity and biodegradability by forming a copolymer comprising two specified types of structural units and to obtain a detergent composition comprising this builder and a surfactant component and having excellent detergency. SOLUTION: This invention provides an acrylic polymer comprising 70-98mol% structural units represented by formula (wherein X is H, an alkali metal or ammonium; R<1> is H or methyl), 2-30mol% structural units represented by formula II (wherein R<1> is as defined above) and 1-50mol% structural units represented by formula III [wherein R<2> is H, methyl, -OH or CH2 COOX'; Y and Z are each H, Cl, COOX', -SO3 ', -OH, -OCOR', -COR', -CONH2 , or CHO (wherein X' is H, is H, an alkali metal or ammonium); and R1 is a 1-12 C alkyl), Ys or Zs are the same or different from each other and do not include groups represented by formula I] and having a number-average molecular weight of 300-100,000, a biodegradable builder containing this polymer as the principal component and a detergent composition comprising this builder and a surfactant.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an acrylic polymer,
The present invention relates to a biodegradable builder made of the acrylic polymer, and a detergent composition containing the biodegradable builder.
More specifically, the present invention relates to an acrylic polymer having a special molecular structure, an economically advantageous builder made of the polymer having excellent chelating ability and biodegradability, and a detergent containing the builder. It relates to a composition.

[0002]

2. Description of the Related Art Conventionally, in detergents containing a surfactant as a main component, the washing performance has been improved by incorporating a builder as an auxiliary component of the surfactant. Known examples of this builder include inorganic compounds that show alkalinity when added to water and polymers of unsaturated aliphatic carboxylic acids. Examples of the former include sodium and potassium carbonates, hydrogen carbonates, phosphates, polyphosphates, silicates and zeolites, and examples of the latter include polyacrylic acid, polymaleic acid, polyitaconic acid. And so on.

Among these builders, phosphates, polyphosphates and zeolites are used in large amounts from the viewpoints of effect, economy and workability. However, phosphates and polyphosphates cause eutrophication of lakes and rivers, and zeolite has a problem of depositing. Therefore, as a builder polymer having chelating ability and biodegradability, it has almost no chelating ability by itself, but has a main chain of water-soluble oligomers containing a certain amount or more of a component having a low molecular weight that is biodegradable. A hydrophilic cross-linked polymer which is bonded through a biodegradable ester group or amide group by a cross-linking agent such as polyethylene glycol, citric acid or tartaric acid to increase the molecular weight and to have a chelating ability as the cross-linked polymer. Is JP-A-5
No. 239127.

However, the linear polyacrylic acid itself, which has a low molecular weight, is hardly biodegradable and contains a large amount of high molecular weight polyacrylic acid which does not biodegrade. Biodegradability is not sufficient. Further, it has a chelating ability and biodegradability that can be produced economically and advantageously by a simpler process because it has two steps of polymerizing an oligomer and crosslinking, and also requires the specific crosslinking agent. There is a need for builder polymers.

[0005]

Under the circumstances, the present invention provides an economically advantageous builder having excellent chelating ability and biodegradability, and a cleaning ability comprising the builder and a surface-active ingredient. It is an object of the present invention to provide a cleaning composition that is excellent in the environmental protection and suppresses environmental pollution or destruction.

[0006]

Means for Solving the Problems As a result of intensive studies for achieving the above-mentioned object, the present inventors have found a new specific acrylic acid-based polymer, and the polymer has excellent chelating ability. It has been found that it is biodegradable, can be efficiently produced by a simple process, is economically advantageous, and that a useful detergent can be obtained by adding it to a surfactant. The present invention has been completed based on such findings.

That is, the present invention is as follows. (1) (a) General formula (I)

[0008]

[Chemical 6]

(Wherein X represents a hydrogen atom, an alkali metal atom or an ammonium group, and R ¹ represents a hydrogen atom or a methyl group), 70 to 98 mol% of a structural unit, and (b)
General formula (II)

[0010]

[Chemical 7]

An acrylic polymer comprising 2 to 30 mol% of a structural unit represented by the formula (wherein R ¹ is the same as above) and having a number average molecular weight of 300 to 100,000. (2) (a) General formula (I)

[0012]

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(In the formula, X represents a hydrogen atom, an alkali metal atom or an ammonium group, and R ¹ represents a hydrogen atom or a methyl group), and the structural unit is 20 to 97 mol%, and (b)
General formula (II)

[0014]

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2 to 30 mol% of the structural unit represented by the formula (wherein R ¹ is the same as above), and (c) the general formula (III)

[0016]

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[In the formula, R ² is a hydrogen atom, a methyl group, or -O.
H or 'indicates, Y and Z are each a hydrogen atom, a chlorine _{atom, -COOX' -CH 2 COOX, -} SO 3 X ', -
OH, -OCOR ', - COR' , - CONH 2 or -
CHO (X 'is a hydrogen atom, an alkali metal atom or an ammonium group, and R'is an alkyl group having 1 to 12 carbon atoms). Y and Z may be the same or different for each unit. However, the general formula (I) is not included. ] 1 to 50 mol% of the structural unit represented by, and the number average molecular weight is 300
An acrylic polymer of 100 to 100,000. (3) A biodegradable builder comprising the acrylic polymer described in (1) or (2) above. (4) A detergent composition containing a surface-active component and the biodegradable builder according to (3) above.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION The acrylic polymer (A) or acrylic polymer (B) of the present invention has the following features. The acrylic polymer (A) has the general formula (I)

[0019]

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The structural unit (I) represented by the general formula (II)

[0021]

[Chemical 12]

It is composed of a structural unit (II) represented by In the above general formulas (I) and (II), X is a hydrogen atom, an alkali metal atom or an ammonium group. R ¹ is a hydrogen atom or a methyl group. Examples of the alkali metal atom include lithium, sodium and potassium. These X and R ¹ may be the same or different for each unit. However, the general formula (II) is
Does not include general formula (I).

Regarding the content ratio of the (I) structural unit and the (II) structural unit in this acrylic polymer (A), the (I) structural unit is 70 to 98 mol% and the (II) structural unit is 2 to It is selected in the range of 30 mol%. In addition, the molecular structure of the polymer (A) is different from the structure of a conventional linear polyacrylic acid according to the measurement of infrared absorption spectrum and nuclear magnetic resonance spectrum. You can see that

The content ratio of each structural unit, the number of continuous structural units, and the state of the combination thereof are hydrogen peroxide,
This can be achieved by selecting conditions such as time for treating acrylic acid with hydrogen peroxide, pH during polymerization, temperature and time. Also, this acrylic polymer (A)
Has a number average molecular weight in the range of 300 to 100,000. The number average molecular weight is 30 to 12 at the time of polymerization.
It is obtained under conditions selected from 0 ° C. and a monomer concentration range of 5 to 80% by weight of acrylic acid.

The number average molecular weight is a value measured by gel permeation chromatography (GPC) using polyacrylic acid as a standard substance. The acrylic polymer (A) includes those in which the carboxyl group in the molecule is completely free, and those in which partial or complete alkali metal salt type or ammonium salt is used. On the other hand, the acrylic polymer (B), (I) structural unit represented by the general formula (I), (II) structural unit represented by the general formula (II), and the general formula (II
I)

[0026]

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(III) structural unit represented by In the general formula (III), R ² is a hydrogen atom,
Methyl, -OH or -CH ₂ COOX '. Y and Z are a hydrogen atom, a chlorine atom, -COOX ',
-SO ₃ X '(X' is a hydrogen atom, an alkali metal atom or an ammonium group), - OH, -OCOR ', - COR'
(R 'is an alkyl group having 1 to 12 carbon atoms), -CONH ₂
Or, it is -CHO. Examples of the alkali metal atom represented by X ′ include lithium, sodium, potassium and the like. The Y and Z may be the same or different for each unit. However, it does not include structural units based on acrylic acid, methacrylic acid, and crotonic acid, which are in agreement with general formula (I). The above in this acrylic polymer (B)
Regarding the content ratio of the (I) structural unit, the (II) structural unit, and the (III) structural unit, the content of the (I) structural unit is 20 to 97 mol%, and the (II)
The structural unit is 2 to 30 mol% and (III) the structural unit is 1 to 5
It is selected in the range of 0 mol%.

The molecular structure of the polymer (B) is measured by infrared absorption spectrum and nuclear magnetic resonance spectrum.
Unlike the structure like the conventional linear polyacrylic acid,
It can be seen that it has a branched structure via an ester bond. The content ratio of each structural unit, the number of consecutive structural units, the state of their combination, hydrogen peroxide, the time when treating acrylic acid with hydrogen peroxide, the time when treating acrylic acid with hydrogen peroxide This can be achieved by selecting the amount of sulfuric acid and organic sulfonic acid, the ratio of copolymerized monomers at the time of polymerization, pH, temperature, and conditions such as time.

The acrylic copolymer (B) has a number average molecular weight selected from the range of 300 to 100,000.
This number average molecular weight can be obtained by setting the polymerization conditions such that the temperature is 30 to 120 ° C. and the monomer concentration of acrylic acid is 50 to 80% by weight, and the range of 5,000 to 20,000 is particularly easy to obtain. The acrylic polymer (B)
Include those in which the carboxyl group and sulfonic acid group in the molecule are completely free, as well as those in which partial or complete alkali metal salt type or ammonium salt type is used.

In a preferred embodiment of the acrylic polymer (A) or acrylic polymer (B) of the present invention, acrylic acid in which R ^{1 of the} structural unit (I) and the structural unit (II) is a hydrogen atom is used. It is used as a raw material. It can be said that acrylic acid is preferable because of its reactivity, raw material cost, availability of raw material, chelating ability, and the like.

The biodegradable builder of the present invention contains an acrylic polymer (A) or an acrylic polymer (B) as a main component. The acrylic acid polymer (A) which is the main component is
In the polymer (A), the content ratio of the (I) structural unit and the (II) structural unit is 70 to 98 mol% of the (I) structural unit and 2 to 30 mol of the (II) structural unit. It is selected in the range of%. If the amount of the structural unit (I) is less than 70 mol%, the chelating ability will be poor, and if it exceeds 98 mol%, the biodegradability will be lowered and the chelating ability will be lowered. From the aspect of the balance of chelating ability and biodegradability, the (I) structural unit is
A proportion of 8 to 90 mol% and 10 to 22 mol% of the (II) structural unit is preferable.

The acrylic polymer (A) which is the main component of the biodegradable biobuilder has a number average molecular weight of 300 to 10
It is in the range of 000. This number average molecular weight is 3
If it is less than 00, the chelating ability is poor, and 100,000 is obtained.
If it exceeds, the biodegradability will decrease. From the viewpoint of the balance between chelating ability and biodegradability, the number average molecular weight is preferably in the range of 1,000 to 25,000, and more preferably the number average molecular weight is in the range of 5,000 to 20,000. The number average molecular weight is a value measured by gel permeation chromatography (GPC) using polyacrylic acid as a standard substance.

The acrylic copolymer (A) may have a completely free carboxyl group in the molecule, or may have a partial or complete alkali metal salt type or ammonium salt type. In the present invention, the acrylic polymer (A) as a main component biodegradable builder, other than the case of only the acrylic polymer (A), a polymerization initiator, a polymerization catalyst, a pH adjuster In some cases, it may include those used in the polymerization, decomposed products thereof, or builder components added if desired.

On the other hand, the acrylic acid polymer (B) as the main component
Is the above polymer (B), and the content ratio of the (I) structural unit, the (II) structural unit, and the (III) structural unit is 20 to 97 mol% of the (I) structural unit, ) 2 to 30 mol% of structural units and 1 to 50 mol% of (III) structural units are selected. If the content of the structural unit (I) exceeds 97 mol%, the biodegradability may decrease and the chelating ability may decrease. If the structural unit (II) is less than 2 mol%, the biodegradability will be poor, and if it exceeds 30 mol%, the chelating ability will be deteriorated. On the other hand, the (III) structural unit is mainly introduced for the purpose of improving the chelating ability, and when the content is less than 1 mol%, (I)
II) The effect of introducing the structural unit is not sufficiently exerted, and if it exceeds 50 mol%, the biodegradability may decrease. From the viewpoint of biodegradability and chelating ability, the preferable ratio of each structural unit is (I) structural unit 68 to 80 mol%, (II) structural unit 10 to 22 mol% and (III) structural unit 5 ~ 2
The range is 0 mol%.

The acrylic polymer (B), which is the main component of the biodegradable builder, has the same number average as the acrylic polymer (A) in terms of biodegradability and chelating ability. The molecular weight is in the range of 300 to 100,000, preferably 1,000 to 25,000, and particularly preferably in the range of 5,000 to 20,000.

The acrylic copolymer (B) may have a completely free carboxyl group or sulfonic acid group in the molecule, or may have a partial or complete alkali metal salt type or ammonium salt type. It may be. In the present invention, the biodegradable builder having an acrylic polymer (B) as a main component is a polymerization initiator, a polymerization catalyst, a pH adjusting agent, in addition to the case where the acrylic polymer (B) alone is used. In some cases, it may include those used in the polymerization, decomposed products thereof, or builder components added if desired.

The detergent composition according to the present invention is a detergent composition comprising the acrylic polymer (A) or (B) according to the present invention as a main component and a biodegradable builder and a surface active ingredient. However, examples of the surfactant component used in combination with the builder include surfactants such as anionic surfactants, cationic surfactants, nonionic surfactants and amphoteric surfactants.

Examples of the anionic surfactant used in the present invention include fatty acid soap, alkyl ether carboxylate, N-acyl amino acid salt, alkylbenzene sulfonate, alkylnaphthalene sulfonate,
Dialkyl sulfosuccinate, α-olefin sulfonate, higher alcohol sulfate, alkyl ether sulfate, polyoxyethylene alkylphenyl ether sulfate, fatty acid alkylolamide sulfate, alkyl ether phosphate, alkyl Examples thereof include phosphate ester salts.

Examples of the cationic surfactants include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts and imidazolinium salts. Examples of the nonionic surfactant include polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene polyoxypropylene block polymer, polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, Polyoxyethylene castor oil, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, polyethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, fatty acid alkanolamide, polyoxyethylene fatty acid amide, polyoxyethylene Examples thereof include alkylamine and alkylamine oxide.

Examples of the amphoteric surfactant include carboxybetaine type compounds, aminocarboxylic acid salts, imidazolinium betaine and the like. Acrylic polymers (A) and (B) of the present invention can be produced by various methods, but according to the method of the present invention as shown below,
It can be easily manufactured.

A typical example of the method for producing an acrylic polymer of the present invention is represented by the general formula (IV)

[0042]

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(In the formula, R ¹ represents a hydrogen atom or a methyl group.) A acrylic acid is polymerized using a percarboxylic acid represented by the formula as a polymerization initiator. The structural unit represented by the general formula (II) is considered to be one in which the above-mentioned percarboxylic acid is incorporated into the molecular chain, and from there, the polymerization of acrylic acids further starts, resulting in the formation of a branched structure.

The percarboxylic acid is preferably produced by reacting acrylic acid with which the percarboxylic acid is obtained with hydrogen peroxide, and the hydrogen peroxide is usually 25 to 7
5 wt% hydrogen peroxide water, preferably 30 to 70 wt% hydrogen peroxide water is used. As acrylic acids, acrylic acid, methacrylic acid and the like are preferable, and strong acid together with hydrogen peroxide solution, for example, sulfuric acid, fuming sulfuric acid, perchloric acid, nitric acid, hydrochloric acid, fluorosulfuric acid, other organic sulfonic acid,
It is preferable to add one selected from those having an acid dissociation index pKa of 3 or less in an aqueous solution system in an amount of 1 to 10% by weight based on the total weight.
By adding these, the production of percarboxylic acid can be promoted. As the organic sulfonic acid, benzenesulfonic acid, toluenesulfonic acid, sulfonic acid type ion exchange resin and the like are suitable.

A specific example thereof is a method in which acrylic acid and hydrogen peroxide are allowed to coexist in an aqueous medium, and the above-mentioned acrylic acid is polymerized while producing their percarboxylic acid. This depends on the conditions such as hydrogen peroxide concentration and the addition of strong acid, but the pH of the polymerization system should be 7
Or less, preferably 5 or less, usually 30 to 12
It may be carried out at a temperature in the range of 0 ° C, preferably 70 to 100 ° C. If the pH of the polymerization system exceeds 7, the desired acrylic polymer cannot be obtained.

In this polymerization reaction, a water-soluble reducing agent may be used in combination with hydrogen peroxide as a polymerization initiator, if desired. Examples of the water-soluble reducing agent include ethylenediaminetetraacetic acid or its sodium salt or potassium salt, or a complex compound of these with a heavy metal such as iron, copper or chromium, sulfinic acid or its sodium salt or potassium salt, L-ascorbic acid. Or its sodium salt, potassium salt, calcium salt, ferrous pyrophosphate, ferrous sulfate, ferrous ammonium sulfate, cobalt chloride, cobalt acetate, sodium sulfite, sodium acid sulfite, sodium formaldehyde sulfoxylate, reducing sugars, etc. Is mentioned. These may be used alone or in combination of two or more. Among these, especially L-
Ascorbic acid and its sodium, potassium and calcium salts are preferred. At this time, sulfuric acid or organic sulfonic acid may be added in a total amount of 0.1 to 10% by weight. As the organic sulfonic acid, benzenesulfonic acid, toluenesulfonic acid and sulfonic acid type ion exchange resin are suitable.

If desired, this polymerization reaction may be carried out in the presence of a chain transfer agent. The type of the chain transfer agent is not particularly limited, and one or more can be arbitrarily selected from those conventionally used in aqueous solution polymerization of acrylic acids, and mercaptoethanol is particularly preferable. The polymerization time varies depending on the polymerization temperature and other conditions and cannot be determined unconditionally, but is usually about 30 minutes to 10 hours.

After the completion of the polymerization reaction, the produced polymer is used as it is, or after being partially or completely converted to an alkali metal salt or ammonium salt using an alkali metal hydroxide or ammonia, it is isolated by a conventional method. Although the desired acrylic polymer can be obtained, it can be used for a biodegradable builder without isolation, in a state in which the compound used for the polymerization or its decomposition product is mixed.

As another specific example, first,
In an aqueous medium, acrylic acid is converted to hydrogen peroxide or
After being treated in the presence of hydrogen peroxide and a strong acid, this treated product is mixed with acrylic acid, and then the pH of the polymerization system of the resulting mixture is kept at 7 or lower, usually 30 to 120.
℃, preferably at a temperature in the range of 70 ~ 100 ℃, 3
There is a method of performing aqueous solution polymerization for about 0 minutes to 10 hours.

In this method, the treatment of acrylic acids with hydrogen peroxide or hydrogen peroxide and a strong acid in an aqueous medium is carried out at a temperature of about 25 to 50 ° C. and usually for about 10 minutes to 3 hours. At this time, the pH is 7 or less, preferably 5 or less. If the pH exceeds 7, the desired acrylic polymer cannot be obtained. Further, in this method, hydrogen peroxide is usually used as hydrogen peroxide, but a water-soluble inorganic peroxide that produces hydrogen peroxide in the reaction system can also be used. Further, the organic sulfonic acid is as described above.

Further, in this polymerization reaction, aqueous solution polymerization may be carried out in the presence of a water-soluble reducing agent or a chain transfer agent, if desired, as in the case of the above reaction. Also,
After the completion of the polymerization reaction, the produced polymer is used as it is or after it is led to a partial or complete alkali metal salt or ammonium salt using an alkali metal hydroxide or ammonia, and then isolated by a conventional method to obtain a desired polymer. Although an acrylic polymer is obtained, it can be used for a biodegradable builder without isolation, in the state where the compound used for polymerization or its decomposition product is mixed. Furthermore, the acrylic polymer has the general formula (V) in addition to the above acrylic acids.

[0052]

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(Wherein R ² , Y and Z are the same as above, except acrylic acid, methacrylic acid and crotonic acid), and added as a polymerization initiator. By using acrylic acid and hydrogen peroxide or acrylic acid and hydrogen peroxide and a strong acid to generate a percarboxylic acid and polymerizing in the same manner as in the method for producing an acrylic polymer described above, a desired acrylic polymer is obtained. Is obtained.

Examples of the polymerizable unsaturated compound represented by the general formula (V) include maleic acid, itaconic acid, fumaric acid, crotonic acid, α-hydroxyacrylic acid, vinylsulfonic acid, allylsulfonic acid and vinyl. In addition to toluenesulfonic acid and alkali metal salts, ammonium salts thereof, alcohol esters having 1 to 12 carbon atoms, acrylamide, acrolein and the like can be mentioned.

These polymerizable unsaturated compounds can be selected in the range of 1 to 50 mol% with respect to 50 to 99 mol% of the above acrylic acids of the acrylic polymer. The acrylic polymer thus obtained can also be used as a biodegradable builder in a state where the compound used for the polymerization and its decomposition product are not isolated as described above.

[0056]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The number average molecular weight of the polymer, the content of the structural unit, the Ca ion chelating ability, the biodegradation rate, and the detergency were determined by the following methods. (1) Number average molecular weight Polyacrylic acid was measured by gel permeation chromatography (GPC) as a standard substance. As the measurement conditions, ALC / GPC 1 manufactured by Waters, Inc.
50C device (detector: built-in differential refractometer, column: ASA)
Using HIPAK (GSM-700 + GS310),
The mobile phase was acetonitrile / 50 mM sodium acetate = 3.
/ 7, column temperature 40 ° C., flow rate 0.7 ml / mi
n, the injection volume was 200 μl.

(2) Number average molecular weight after hydrolysis 3 g of the sample was dissolved in 25 ml of water, sodium hydroxide was added to adjust the pH to 11, and the mixture was heated and stirred at 80 ° C. for 1 hour for hydrolysis. After completion of the reaction, the pH was adjusted to 7 to 8 and the number average molecular weight of the sample obtained by freeze-drying was measured in the same manner as in (1) above.

(3) Content of Each Structural Unit The number average molecular weight before hydrolysis is M ₁ , the number average molecular weight after hydrolysis is M _2, and the structural unit (I) or (I) is calculated from the following formula.
The content of + (III) was determined.

[0059]

[Equation 1]

In this formula, acrylic acid (molecular weight = 7
Applicable in case 2). The content of the structural unit (III) is
It was calculated from the yield or the content of unreacted monomer.
Further, in order to clarify the molecular structure and the content of the structural unit, measurement by ¹ H-NMR was also performed. The structural unit (I) or (I) + (III) is a proton of the main chain of the polymer from ¹ H-NMR of FIGS. 1 and 3, specifically,

[0061]

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0.8 derived from protons underlined
From the peak area of ~ 3.0 ppm, the structural unit (I
I) is the peak area derived from protons of —COO—CH ₂ — (4.1 to 4.6 pp for deuterated chloroform solvent).
m, 4.2 to 4.5 ppm in heavy water solvent). The amount of the structural unit (III) can be determined from the peak area and the like due to the polymerizable unsaturated compound. This measurement was carried out using a JSX GSX400 device in a solvent of deuterated chloroform or deuterated water at a polymer concentration of 5%.
The solution of less than 5 is put into a test tube having a diameter of 5 mm,
It was conducted by integrating 32 times in 400 MHz and SGNON mode.

(4) Ca ion chelating ability 10 mg of polymer was placed in a 50 ml beaker, and an aqueous solution containing calcium chloride 0.001 mol / liter and potassium chloride 0.08 mol / liter 5
0 ml was added and mixed in a thermostat at 25 ° C., and the concentration of divalent Ca ions in the aqueous solution was measured by an ion meter. Ca ion chelating ability is 100 g of polymer
Ca ion amount chelated by (g / 100
Expressed as g).

(5) Biodegradation rate The biochemical oxygen demand (BOD) is JIS K01.
According to No. 02-1989, it was determined from the amount of dissolved oxygen consumed when the mixture was stirred at 25 ° C. for 30 days, and the biodegradation rate was calculated according to the following formula. Biodegradation rate (%) = (BOD / TOD) × 100 BOD: biochemical oxygen demand of sample TOD: theoretical oxygen demand of sample

(6) Detergency An artificial dirt was prepared by mixing the following organic dirt components with calcined clay and carbon black in a ratio of 69.7: 29.8: 0.5 (weight ratio).

Oleic acid 28.3 parts by weight Triolein 15.6 parts by weight Cholesterol olein 12.2 parts by weight Liquid paraffin 2.5 parts by weight Squalene 2.5 parts by weight Cholesterol 1.6 parts by weight Gelatin 7.0 parts by weight Total 69.7 parts by weight Using this artificial dirt, a contaminated cloth is prepared from a clean cloth by a water-solvent wet method, and cut into 5 cm × 5 cm to prepare a cloth having a reflectance of 38 to 43%, After the surface reflectance before cleaning was measured, it was subjected to a cleaning test under the following conditions.

[0067] - wash conditions - tester Terg-O-Tometer rotational speed 120rpm water hardness 90 ppm (CaCO ₃ conversion) washes volume 900 ml wash temperature 30 ° C. wash concentration 0.067% bath ratio 30 times washing time 10 min rinse Dry for 3 minutes twice, dry with iron sandwiched between papers, then measure the surface reflectance of the washed cloth (wash cloth),
The detergency was calculated from the following formula.

Detergency (%) = (K / S of dirty cloth-K / S of clean cloth) / (K / S of dirty cloth-K / S of clean cloth) × 1
00 [where K / S = (1-R) ² / 2R (Kubelka-Munk
Where R is the surface reflectance of the cloth. ]

Example 1 In a separable flask having a capacity of 500 ml equipped with a stirrer, a reflux condenser, a thermometer, a pH meter and a chemical pump, 50 ml of water and 24 m of L-ascorbic acid were placed.
g, and kept at a temperature of 98 to 100 ° C. to this,
100 ml of an aqueous solution containing 60 g of acrylic acid, 3
Aqueous solution containing 60 ml of 0 wt% hydrogen peroxide solution 8
A mixed solution of 0 ml and 2 g of mercaptoethanol as a chain transfer agent and 30 ml of water was added dropwise by a chemical pump over 3 hours. During this period, the pH of the polymerization liquid was 2.9. After the dropping was completed, the same temperature was maintained for 1 hour to complete the polymerization. The polymer obtained was isolated by freeze-drying.

¹ H-NM of a solution of the obtained polymer obtained by methyl esterification in a heavy chloroform solvent
R is as shown in FIG. 1, and the peak of methylene in contact with the ester was confirmed at 4.1 to 4.6 ppm. In addition,
¹ H-NMR of a conventionally known acrylic acid-based polymer having no branched structure is as shown in FIG. Moreover, ¹ H-NM of the obtained polymer was made into a solution in a heavy water solvent.
R is as shown in FIG. 3, and is derived from the proton of the main chain of the polymer and derived from the proton of methylene in contact with the ester bond of the branching portion for the peak area a of 1.0 to 3.6 ppm. From the ratio of the peak area b of -4.5 ppm, it was confirmed that the structural unit (I) was 95% and the structural unit (II) was 5%. Table 1 shows the properties of this polymer and the builder containing it as a main component.

Example 2 In Example 1, an aqueous solution 10 containing 60 g of acrylic acid was used.
The procedure of Example 1 was repeated, except that 100 ml of an aqueous solution containing 40 g of acrylic acid and 32 g of maleic acid was used instead of 0 ml. However, the pH of the polymerization liquid was 2.5 to 3.0. Table 1 shows the properties of the obtained polymer and the builder containing it as a main component.

Example 3 The same apparatus as in Example 1 was charged with 50 ml of water, and
The temperature was kept at 8-100 ° C. To this, acrylic acid 2
A solution obtained by stirring 0 g, 60 ml of 30% by weight hydrogen peroxide and 500 mg of concentrated sulfuric acid at room temperature for 2 hours, and 100 ml of an aqueous solution containing 40 g of acrylic acid were fed by separate chemical pumps over 3 hours. afterwards,
Further, the mixture was heated and stirred at the same temperature for 1 hour. During this period, the pH of the polymerization liquid was 3.1. Table 1 shows the properties of this polymer and the builder containing it as a main component.

Example 4 50 ml of water was put in the same apparatus as in Example 1, and
The temperature was kept at 8-100 ° C. To this, acrylic acid 2
A solution obtained by stirring 0 g, 60 ml of 30% by weight hydrogen peroxide and 500 mg of concentrated sulfuric acid at room temperature for 2 hours, and an aqueous solution containing 20 g of acrylic acid and 32 g of maleic acid.
Milliliters were fed with separate chemical pumps over 3 hours. Then, the mixture was further heated and stirred at the same temperature for 1 hour. During this period, the pH of the polymerization liquid was 2.5 to 3.0. Table 1 shows the properties of this polymer and the builder containing it as a main component.

Example 5 20 ml of water was placed in a separable flask having a capacity of 500 ml equipped with a stirrer, a reflux condenser, a thermometer, a pH meter and a metering pump, and the temperature was kept at 98 to 100 ° C. An aqueous solution 190 containing 80 g of acrylic acid
Milliliter, 60 ml of 30% by weight hydrogen peroxide and 4 g of mercaptoethanol as chain transfer agent
And a mixed solution of 20 ml of water were supplied by separate metering pumps over 3 hours. During this period, the pH of the polymerization solution was 3.0.
Met. After the supply was completed, the mixture was further heated and stirred at the same temperature for 1 hour. The polymer obtained was isolated by freeze-drying. The properties of this polymer and the builder containing it as the main component are
It is shown in the table.

Example 6 150 ml of water was put in the same apparatus as in Example 1,
The temperature was maintained at 75 ° C to 80 ° C. Acrylic acid 2
A solution prepared by stirring 0 g, 60 ml of 30% by weight hydrogen peroxide and 500 mg of concentrated sulfuric acid at 50 ° C. for 5 hours was supplied by a chemical pump over 3 hours. Then, the mixture was further heated and stirred at the same temperature for 1 hour. During this period, the pH of the polymerization solution was 1.0 to 3.0. The obtained polymer was isolated by freeze-drying. Table 1 shows the properties of this polymer and the builder containing it as a main component.

Comparative Example 1 The pH of the acrylic acid aqueous solution added dropwise in Example 1
Was carried out in the same manner as in Example 1 except that sodium hydroxide was adjusted to 7.5. The pH of the polymerization liquid during the dropwise addition was 7.1 to 7.8. Table 1 shows the properties of the obtained polymer and the builder containing it as a main component.

Comparative Example 2 The pH of the acrylic acid aqueous solution added dropwise in Example 5
Was carried out in the same manner as in Example 5 except that the concentration was adjusted to 8.1 with sodium hydroxide. The pH of the polymerization liquid during dropping was 7.5 to 8.6. Table 1 shows the properties of the obtained polymer and the builder containing it as a main component.

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[Table 1]

[0079]

[Table 2]

Examples 7 to 12 and Comparative Examples 3 to 9 A detergent composition containing the following components was used to test the detergency. (1) Linear alkylbenzene sulfonate sodium (LA
Abbreviated as S). (2) Sodium alkyl sulfate (abbreviated as ASS). (3) Sodium polyoxyethylene alkyl sulfate (AE
Abbreviated as S). (4) Nonionic surfactant (abbreviated as NSF). (5) The acrylic acid-based polymer described in Example 1 (abbreviated as PA-1). (6) The acrylic acid-based polymer described in Example 4 (abbreviated as PA-5). (7) Polyacrylic acid (number average molecular weight 8000) (PA8
And abbreviated). (8) Polyacrylic acid (number average molecular weight 15,000) (PA
(Abbreviated as 15). (9) Sodium tripolyphosphate (abbreviated as TPS). (10) Type A zeolite (abbreviated as AZE). (11) Sodium silicate (abbreviated as SiS). (12) Polyethylene glycol (abbreviated as PEG). (13) Sodium carbonate (abbreviated as CAS). (14) Sodium sulfate (abbreviated as SAS). (15) Water (abbreviated as H ₂ O). The results are shown in Table 2.

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[Table 3]

[0082]

The novel acrylic polymer according to the present invention has a unique molecular structure and can be used as a biodegradable builder containing the polymer as a main component. Not only is it decomposable, but it is also excellent in chelating ability and can be mixed with various surface-active ingredients to obtain a suitable detergent composition.

[Brief description of drawings]

1 shows the structural units (I) and (I obtained in Example 1).
¹ H-NMR absorption spectrum of acrylic polymer consisting of (I) (deuterated chloroform solvent after methyl esterification)

FIG. 2 ¹ H-NMR absorption spectrum of an ordinary unbranched acrylic polymer consisting of structural unit (I) only.

FIG. 3 shows structural units (I) and (I obtained in Example 1).
¹ H-NMR absorption spectrum of acrylic polymer (I) (heavy water solvent)

Claims (4)

[Claims] (A) General formula (I): (Wherein X represents a hydrogen atom, an alkali metal atom or an ammonium group, and R ¹ represents a hydrogen atom or a methyl group), and 70 to 98 mol% of a structural unit represented by the formula (II): Chemical 2] (In the formula, R ¹ is the same as above.) And the structural unit is 2 to 30 mol%, and the number average molecular weight is 30.
An acrylic polymer of 0 to 100,000. (A) General formula (I): (In the formula, X represents a hydrogen atom, an alkali metal atom or an ammonium group, and R ¹ represents a hydrogen atom or a methyl group.) 20 to 97 mol% of a structural unit represented by the formula (b) Chemical 4] (Wherein R ¹ is the same as above), and 2 to 30 mol% of the structural unit represented by the formula (c) [In the formula, R ² is a hydrogen atom, a methyl group, —OH or —CH
'Indicates, Y and Z each represents a hydrogen atom, a chlorine _{atom, -COOX' 2 COOX, - SO} 3 X ', - OH, -OC
OR ', - COR', - CONH 2 , or -CHO (X '
Is a hydrogen atom, an alkali metal atom or an ammonium group,
R'represents an alkyl group having 1 to 12 carbon atoms. Y and Z
May be the same or different for each unit. However, the general formula (I) is not included. ] The structural unit represented by 1 to 50 mol%, and the number average molecular weight is 300 to 100,00.
An acrylic polymer that is 0. 3. A biodegradable builder comprising the acrylic polymer according to claim 1. 4. A detergent composition comprising a surface-active component and the biodegradable builder according to claim 3.