JPH1053648A - Block copolymer, its production and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a block copolymer for cement dispersing agent, etc., having a polyalkylene glycol structural unit and a polyglyoxylate structural unit and excellent in dispersing property as well as chelate formability and scale preventing performance. SOLUTION: This block copolymer comprises a polyalkylene glycol structural unit represented by formula I [(n) is 2-4; average value of (x) is >=5] and a polyglyoxylate structural unit represented by formula II [M is H, a 1-4C alkyl, a mono- to tri-valent metal atom, ammonium group or an organic amine; average value of (y) is >=10]. Furthermore, the polymer is obtained by subjecting a glyoxylic acid-based monomer to polymerization reaction with a polyalkylene glycol represented by formula III (R<1> is H, an alkyl, an alkenyl, etc.) in a polymerization reaction system in which water content is <=30mol% based on the compound represented by formula III in the presence of a catalyst (e.g. an anion polymerization catalyst such as diethyl zinc) and saponifying the resultant polymer with an alkaline substance such as sodium hydroxide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a block copolymer excellent in dispersibility and the like, its use as a detergent builder, and the like, and a method for producing a block copolymer.

[0002]

2. Description of the Related Art Hitherto, polyether block copolymers comprising structural units derived from ethylene oxide and propylene oxide have been known. Although such a block polymer has surface activity, when used as a pigment dispersant, the performance is not satisfactory. Similarly, when used as a water treatment agent, the scale prevention performance is not satisfactory, and when used as a dispersant for trapping hardness components in water and dispersing mud dirt.

As a polymer containing structural units derived from both an alkylene oxide and a carboxylic acid, US Pat. No. 4,204,052 discloses a random copolymer composed of structural units derived from ethylene oxide and a glyoxylic acid derivative. ing. Also, U.S. Pat.
No. 26 discloses a polymer of glyoxylic acid,
This polymer has ethylene glycol monoether derivatives at both ends obtained by reacting 1 to 3 molecules of ethylene oxide with both ends of the polymer molecule for stabilization. All of the polymers described in these US patents are described for use in detergent builders.

[0004]

SUMMARY OF THE INVENTION US Patent No. 42040
In the random copolymer of No. 52, carboxylate ions are randomly arranged in the polymer. For example, when this polymer is used as a cement dispersant, any portion of the polymer side chain is negatively charged to the same extent and almost uniformly adsorbs to cement particles, and adsorbs to cement particles. It is considered that the polymer portion that has not been absorbed is small, and it is not expected that the cement particles are effectively dispersed by the steric repulsion between the polymer portions that are not adsorbed. Also, when the homopolymer disclosed in U.S. Pat. No. 4,144,226 is used as a cement dispersant, the contribution of the terminal alkylene oxide portion of the polymer is small, so that the polymer is strongly adsorbed to positively charged cement particles, and In addition, cement particles cannot be effectively dispersed.

Further, none of the polymers described in the above-mentioned US Patents has a continuous alkylene oxide group, and therefore, when used as a detergent builder, the dispersibility is not sufficient, the cleaning performance is low, and It is poor in biodegradability. The problem to be solved by the present invention is to provide a novel block copolymer having a chemical structure different from that described above, having excellent dispersibility, and having excellent chelating ability and scale prevention performance. is there.

Another object to be solved by the present invention is to provide a cement dispersant and a pigment dispersant having excellent dispersibility. Still another object to be achieved by the present invention is to provide a water treatment agent having excellent dispersibility, chelating ability and scale prevention ability. Still another object to be achieved by the present invention is to provide a detergent builder having excellent dispersibility and chelating ability, high cleaning performance, and excellent biodegradability, and a detergent composition containing the detergent builder. It is.

[0007] Still another object of the present invention is to easily and efficiently produce a novel block copolymer having excellent dispersibility, excellent chelating ability and anti-scale performance.

[0008]

Means for Solving the Problems In order to solve the above problems, the present inventors have prepared a polymer having a polyether structural unit and a polycarboxylate structural unit having a degree of polymerization of a certain degree or more in a block structure. If so, the present inventors have completed the present invention on the assumption that the function of the polycarboxylate block and the function of the polyether block portion are effectively exhibited.

That is, the block copolymer of the present invention comprises:
It contains a polyalkylene glycol structural unit represented by the following general formula (1) and a polyglyoxylate structural unit represented by the following general formula (2).

[0010]

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(However, n is an integer of 2 to 4 and the average value of x is 5 or more.)

[0012]

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(Where M is one selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a 1 to 3 valent metal atom, an ammonium group and an organic amine group, and the average value of y is 10 or more. The block copolymer according to claim 1, wherein the structure of at least one terminal of the polymer is selected from the structures represented by the following general formulas (3) and (4).

[0014]

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(However, n is an integer of 2 to 4, and R ¹ is ^one selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group.)

[0016]

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(Where M is one selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a metal atom having 1 to 3 valences, ammonium and an organic amine, and X is a depolymerization of a block copolymer. The cement dispersant of the present invention contains the block polymer. The pigment dispersant of the present invention contains the block polymer.

The water treatment agent of the present invention contains the block polymer. The detergent builder of the present invention contains the block polymer. The detergent composition of the present invention is a detergent composition comprising a surfactant and the detergent builder as essential components, wherein the surfactant is an anionic surfactant, a nonionic surfactant, or a cationic surfactant. At least one selected from a surfactant and an amphoteric surfactant,
10 to 60% by weight of the surfactant in the detergent composition
Wherein the detergent builder is 0.1 to 60% by weight.

The method for producing the block copolymer of the present invention comprises:
In a polymerization reaction system having a water content of 30 mol% or less with respect to the polyalkylene glycol represented by the following general formula (5), glyoxylic acid represented by the following general formula (6) is added to the polyalkylene glycol in the presence of a catalyst. It is characterized by polymerizing a system monomer.

[0020]

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(Where R ¹ is a hydrogen atom, an alkyl group,
It is one selected from an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group, n is an integer of 2 to 4, and the average value of x is 5 or more. )

[0022]

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(However, R ² is an alkyl group having 1 to 4 carbon atoms.) It is preferable to further perform a saponification reaction with an alkaline substance to increase the water solubility.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Block Copolymer A block copolymer comprises a polyalkylene glycol structural unit represented by the above general formula (1) and a polyglyoxylate structural unit represented by the above general formula (2). Contains.

The polyalkylene glycol structural unit is represented by the general formula (1) and is a structural unit derived from polyalkylene glycol. In the general formula (1), n is an integer of 2 to 4, and the average value of x is 5 or more. n is not particularly limited as long as it is an integer of 2 to 4, and is any of a polyethylene glycol structural unit where n = 2, a polypropylene glycol structural unit where n = 3, and a polybutylene glycol structural unit where n = 4. However, when used in an aqueous system, it is preferable to use a polyethylene glycol structural unit in which n = 2 because water solubility is improved.

There is no particular limitation as long as the average value of x is 5 or more. If the average value of x is less than 5, dispersibility or scale prevention performance will not be exhibited. The average value of x is preferably 10 or more, and when it is 20 to 1,000, dispersibility,
It is more preferable because of its excellent chelating ability and scale prevention performance, and most preferably from 20 to 500. The polyglyoxylate structural unit is represented by the general formula (2) and is a structural unit derived from polyglyoxylate. In the general formula (2), M is one selected from a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a metal atom having 1 to 3 valences, an ammonium group (NH ₄ ), and an organic amine group. The average value is 10 or more.

Specific examples of the alkyl group having 1 to 4 carbon atoms include methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-
Examples thereof include a butyl group and a tert-butyl group. One or more of these alkyl groups may be used. Specific examples of the trivalent metal atom include lithium, sodium, potassium, magnesium,
Examples include calcium, strontium, barium, aluminum, iron and the like. These metal atoms are 1
A species or a combination of two or more species may be used.

The organic amine group is not particularly limited as long as at least one of the groups bonded to the nitrogen atom is an organic group and has a structure capable of forming a salt with a carboxyl group. Specific examples of such organic amines include ethylamine, n
-Propylamine, isopropylamine, n-butylamine, sec-butylamine, tert-butylamine, allylamine, dimethylamine, diethylamine,
An alkylamine having 1 to 4 carbon atoms such as triethylamine;
Other amines such as dodecylamine, octadecylamine, cyclohexylamine, benzylamine, aniline, dipropylamine, dicyclohexylamine, N, N-dimethyldodecylamine; and alkanolamines such as monoethanolamine, diethanolamine and triethanolamine. Can be. One or more of these organic amines may be used.

M is a hydrogen atom; sodium, potassium,
Metal atoms such as magnesium and calcium; ammonium groups; at least one selected from organic amine groups derived from organic amines such as alkanolamines and alkylamines having 1 to 4 carbon atoms are preferred. When M is an alkyl group having 1 to 4 carbon atoms, the functional group (—COOM) in the polyglyoxylate structural unit represented by the general formula (2) becomes an ester group. On the other hand, when M is one selected from a metal atom having 1 to 3 valences, an ammonium group and an organic amine group, the functional group (—COOM) in the polyglyoxylate structural unit is composed of a carboxylate. It is preferable because it forms a base and generates an affinity with a positively charged substance due to an electrostatic action, thereby increasing the chelating ability and the scale preventing ability. The conversion from the ester group to a group consisting of a carboxylate can be facilitated by a method described later.

The average value of y is not particularly limited as long as it is 10 or more, but if it is less than 10, no improvement in chelating ability and dispersing performance, which is an effect not exhibited by the polyalkylene glycol structural unit, is not recognized. When the average value of y is 20 or more, the chelating ability, the dispersing performance, the scale prevention performance, and the like are excellent, and the average value of y is more preferably 20 to 500.

The blending ratio of the polyalkylene glycol structural unit and the polyglyoxylate structural unit in the block copolymer is not particularly limited, but may be polyalkylene glycol structural unit / polyglyoxylate structural unit (weight ratio). Is preferably 1/9 to 9/1, because the performance is superior to that of the polymer comprising each single structural unit, and more preferably 2/8 to 8/2.

The number average molecular weight of the block copolymer is preferably from 1,500 to 1,000,000, more preferably from 2,000 to 50,000. When the number average molecular weight is out of the above range, effects such as dispersibility exhibited by being a block copolymer cannot be obtained. Regarding the arrangement of each structural unit of the block copolymer, the block copolymer is composed of a polyalkylene glycol structural unit (hereinafter, sometimes referred to as “A”) and a polyglyoxylate structural unit (hereinafter, “B”). Is not particularly limited, as long as it includes the following sequence.

AB-type block copolymer BAB-type block copolymer ABA-type block copolymer A block copolymer obtained by repeating the above-mentioned steps. The structure of the terminal of the polymer is not particularly limited, but at least one terminal of the polymer. Is preferably selected from the structures represented by the general formulas (3) and (4) because the stability of the polymer increases and the handleability is excellent. In addition,
When the end of the repeating portion of the polymer is a polyalkylene glycol structural unit, the structure represented by the general formula (3) (hereinafter, the “structure represented by the general formula (3)” is referred to as “terminal structure a”)
There is that. ) Is the structure of the terminal of the polymer, and when the end of the repeating portion of the polymer is a polyglyoxylate structural unit, the structure represented by the general formula (4) (hereinafter referred to as “general formula (4) "Structure shown" to "terminal structure b"
There is that. ) Is the terminal structure of the polymer.

One end and the other end of the polymer may have the same general formula selected from the general formulas (3) and (4), or may have different general formulas It may be. Further, when one end and the other end of the polymer have a structure represented by the same general formula, each may have exactly the same structure, and may have the same general formula but not the same structure. good.

In the terminal structure a, n is an integer of 2 to 4,
¹ is ^one selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group, and in the case other than a hydrogen atom, each group may be substituted. . Specific examples of the alkyl group used as R ¹ include a methyl group, an ethyl group, a propyl group, an n-butyl group, an iso-butyl group, a lauryl group, and a stearyl group. One or more of these alkyl groups may be used.

Specific examples of the alkenyl group used as R ¹ include a propenyl group and a butenyl group. One or more of these alkenyl groups may be used. Specific examples of the alkylphenyl group used as R ¹ include a toluyl group, a xylyl group, a dodecylphenyl group, a nonylphenyl group, and the like. One or more of these alkylphenyl groups may be used.

In the terminal structure b, M is a hydrogen atom, carbon number 1
It is one selected from alkyl groups of 1 to 4, 1 to 3 valent metal atoms, ammonium groups and organic amine groups, and X is a group which is chemically stable to depolymerization of the block copolymer. A group that is chemically stable to depolymerization is any group that is chemically stable to rapid depolymerization in an alkaline solution.

As M, those exemplified above can be used. The same applies to those preferred as M. X is a 0.5 M aqueous sodium hydroxide solution containing 10 g of a block copolymer per liter,
When the average chain length of the polyglyoxylate structural unit in this block copolymer is measured by NMR, the group is such that the reduction rate of the average chain length after 1 hour at 20 ° C. is less than 50%.

X is preferably an alkyl group, an oxygen-containing alkyl group, an oxygen-containing cyclic alkyl group, or the like. Specific examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a lauryl group, and a stearyl group. Specific examples of the oxygen-containing alkyl group include -CH ₂ COOM ¹ , -C
R ³ (COOM ¹ ) ₂ , —CH (COOM ¹ ) [CH
(OH) COOM ¹ ], -CH (OCH ₂ CH ₃ ) [C
H (COOM ¹⁾ _2] alkyl group (having a carboxyl group such as, M ¹ is a one selected from alkali metal atom, an ammonium group, an alkanolamine and alkyl groups having 1 to 4 carbon atoms, R ³ Is one selected from a hydrogen atom and an alkyl group having 1 to 8 carbon atoms.);
_{-CHCH 3 OCH 2 CH 3, -} (CH 2 CH 2 O)
Alkyl groups having an ether group such as _1-4 H; aldehyde groups and other oxygen-containing alkyl groups; and acyl groups represented by the following general formula (7).

[0040]

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(Where R ¹ is ^one selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group. As the R ¹ in the acyl group, those exemplified above are used. Specific examples of the oxygen-containing cyclic alkyl group include a group represented by the following formula (8).

[0042]

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One or more of these Xs may be used. The block copolymer described above is
It can be suitably used as a cement dispersant, a water treatment agent and a pigment dispersant. Production method of block copolymer The production method of the block copolymer is a polymerization reaction system having a water content of 30 mol% or less with respect to the polyalkylene glycol represented by the general formula (5) in the presence of a catalyst. A glyoxylic acid-based monomer represented by the general formula (6) is polymerized with the polyalkylene glycol.

The polyalkylene glycol has the general formula (5)
And obtained, for example, by polymerizing an alkylene oxide in the presence of a polymerization catalyst. R ¹ in the polyalkylene glycol is ^one selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group, n is an integer of 2 to 4, and the average value of x is 5 or more. And those described in the section of the above block copolymer can be used. The same applies to preferred ones. When R ¹ is a hydrogen atom, the polyalkylene glycol has a hydroxyl group at both terminals, and polymerization of a glyoxylic acid-based monomer described later starts from both terminals of the polyalkylene glycol. Also, R ¹
Is other than a hydrogen atom, the polyalkylene glycol has a hydroxyl group at one end and an ether group at another end, and polymerizes a glyoxylic acid-based monomer from one end of the polyalkylene glycol having a hydroxyl group bonded thereto. Starts.

The glyoxylic acid-based monomer is a glyoxylic acid alkyl ester represented by the general formula (6), R ²
Is an alkyl group having 1 to 4 carbon atoms. Specific examples of the alkyl group having 1 to 4 carbon atoms used as R ² include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an iso-butyl group, a sec-butyl group, A tert-butyl group and the like can be mentioned. One or more of these alkyl groups may be used.

The mixing ratio of the polyalkylene glycol and the glyoxylic acid monomer is not particularly limited,
Polyalkylene glycol / glyoxylic acid-based monomer (a weight ratio of 1/9 to 9/1 is preferable, more preferably a polymer obtained by polymerizing each monomer alone, and is more preferable. Is 2/8 to 8/2.
The production of the block copolymer is performed in the presence of a catalyst. The catalyst is not particularly limited, but specific examples of the catalyst include one selected from a cationic polymerization catalyst and an anionic polymerization catalyst.

Specific examples of the cationic polymerization catalyst include boron trifluoride etherate (BF ₃ .Et ₂ O), trifluoroacetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, phosphorus pentoxide and the like. As specific examples of the anionic polymerization catalyst,
Organometallic compounds such as diethylzinc and n-butyllithium; alkali metal compounds such as potassium hydroxide, sodium hydroxide, calcium hydroxide and magnesium hydroxide; amines such as triethylamine, N, N-dimethyldodecylamine; sodiomethyl Malonate ester; examples thereof include alkali metal alkoxides such as sodium methoxide and potassium methoxide.

In the production of the block copolymer, it is generally preferable to use an anionic polymerization catalyst because the number average molecular weight of the polymer can be easily controlled. The amount of the catalyst used is not particularly limited, and varies depending on the type of the catalyst.
0.001 to 10% by weight of monomer for amine catalyst
It is preferred that

The reaction temperature during the production of the block copolymer is as follows:
The reaction conditions vary depending on the type of catalyst and solvent used, and are not particularly limited, but are usually -50 to
It is performed within the range of 50 ° C. If the temperature is lower than −50 ° C., it is difficult to perform cooling. If the temperature is higher than 50 ° C., the yield of the obtained block copolymer decreases. In the method for producing the block copolymer, any method of solution polymerization using a solvent and bulk polymerization of a solventless system may be used. The solution polymerization can be performed in any of a batch system and a continuous system.

The solvent used in the solution polymerization is miscible with the polyalkylene glycol used in the reaction, the glyoxylic acid-based monomer and the block copolymer obtained by the reaction, and does not participate in undesired side reactions. There is no particular limitation as long as conditions such as the above are satisfied. Specific examples of such a solvent include aromatic hydrocarbons such as benzene, toluene and xylene; aliphatic hydrocarbons such as cyclohexane and n-hexane; halogenated hydrocarbons such as methylene chloride; methyl acetate, ethyl acetate and the like. Ester compounds; ketone compounds such as acetone; ether compounds such as tetrahydrofuran and dioxane. Among them, at least one selected from toluene, methyl acetate, dioxane, and acetone is preferred from the viewpoint of solubility in dissolving the reactants and products and convenience in use.

When the amount of the solvent used is 10 to 2,000 parts by weight based on 100 parts by weight of the obtained copolymer, not only the productivity but also the side reaction can be suppressed. Although it is preferable because the polyalkylene glycol is liquid at the reaction temperature, the reaction may be performed without a solvent. In the method for producing a block copolymer, a polymerization reaction is performed in a polymerization reaction system having a water content of 30 mol% or less based on polyalkylene glycol. The polymerization reaction is preferably carried out in a water content of 10 mol% or less, more preferably 1 mol% or less, and most preferably a non-aqueous system. If the water content is high, the amount of the by-product glyoxylic acid-based monomer homopolymer increases, and the yield of the target block copolymer decreases. For this reason, it is preferable to dehydrate the polyalkylene glycol, the glyoxylic acid-based monomer, and the solvent used as required before starting the polymerization reaction. The method of dehydration is not particularly limited, and examples thereof include azeotropic dehydration and addition of a dehydrating agent.

In the method for producing the block copolymer,
The arrangement of each structural unit in the obtained block copolymer varies depending on the terminal structure of the polyalkylene glycol.
When R ¹ is a hydrogen atom in the polyalkylene glycol, the polyalkylene glycol has a hydroxyl group at both terminals, and the polymerization of the glyoxylic acid-based monomer starts from both terminals of the polyalkylene glycol, and the above-described B , A, and B are obtained. When the terminal structure of the obtained BAB block copolymer is reacted with an alkylene oxide represented by the following general formula (9) without converting the terminal structure into a chemically stable group, the above-mentioned A, B, A , B, and A, an ABABA block copolymer in which structural units are arranged in this order is obtained. Further, when a glyoxylic acid-based monomer is subjected to a polymerization reaction with the obtained ABABA block copolymer, a BABABAB block having structural units arranged in the order of B, A, B, A, B, A, and B described above is obtained. A polymer is obtained.
By repeating such a polymerization reaction, an arbitrary block copolymer can be produced.

[0053]

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(However, n is an integer of 2 to 4.) In the general formula (9), n is preferably ethylene oxide in which n = 2 because it has good solubility when used in an aqueous system. Since R ^{1 in the} polyalkylene glycol is other than a hydrogen atom, the polyalkylene glycol has a hydroxyl group at one end, and the polymerization of the glyoxylic acid-based monomer starts from only one end of the polyalkylene glycol, and AB block copolymer in which the structural units are arranged in the order of A and B is obtained. Further, without converting the structure at the B-terminal of the obtained AB block copolymer into a chemically stable group (Since R ¹ is other than a hydrogen atom, the A-terminal has an ether bond. Therefore, when it is reacted with the alkylene oxide represented by the general formula (9), an ABA block copolymer in which the structural units are arranged in the order of A, B, and A is obtained. Further, when a glyoxylic acid-based monomer is polymerized with the obtained ABA block copolymer, the above-mentioned A,
An ABAB block copolymer in which the structural units are arranged in the order of B, A, and B is obtained. By repeating such a polymerization reaction, an arbitrary block copolymer can be produced. Also in this case, in the general formula (9), n is:
Ethylene oxide with n = 2 is preferred because it has good solubility when used in an aqueous system.

The reaction conditions for the polymerization reaction of the alkylene oxide represented by the above general formula (9) with the block copolymer having a terminal B, and the addition of a glyoxylic acid monomer to the block copolymer having a terminal A. The reaction conditions for the polymerization reaction are the same as the reaction conditions described in detail in the above-mentioned method for producing a block copolymer, and the same applies to preferable ones.

When the terminal is B, the obtained block copolymer is converted into a group which is stable against depolymerization. It is preferable because it becomes stable. When the terminal is A, it is not always necessary to convert the terminal into another group, but it may be converted into a group that is stable against the above-mentioned depolymerization.

As a method for converting the terminal to a group stable to depolymerization, for example, there is a method in which a block copolymer having a terminal B is reacted with a reactive compound in the presence of a reaction catalyst. Specific examples of the reactive compound include alkyl vinyl ethers such as ethyl vinyl ether, butyl vinyl ether, and propyl vinyl ether; propylene,
Substituted olefins such as butylene and methyl acrylate; epoxides such as ethylene oxide, propylene oxide and epichlorohydrin; alcohols such as methanol, ethanol and propyl alcohol; methyl iodide and isochloride
Alkyl halides such as -propyl and tert-butyl chloride; allyl halides such as allyl chloride; acetals such as acetaldehyde dimethyl acetal; alkyl sulfates such as dimethyl sulfate and diethyl sulfate; benzyl halides such as benzyl chloride and benzyl bromide. Can be mentioned. One or two or more of these reactive compounds can be used.

The amount of the reactive compound used is not particularly limited, but is preferably 1.1 to 10 (molar ratio) with respect to the block copolymer having a terminal B. Specific examples of the reaction catalyst include hydrochloric acid, hydrobromic acid, hydroiodic acid,
Protic acids such as trifluoroacetic acid and phosphoric acid; and Lewis acids such as aluminum chloride, alkylaluminum halide and trialkylaluminum. One or more of these reaction catalysts can be used.

The use amount of the reaction catalyst is not particularly limited, and is appropriately determined depending on the type of the catalyst. In the reaction with the reactive compound, the solvent used for producing the block copolymer can be used as it is. The reaction temperature is preferably from 0 to 50 ° C.

The glyoxylic acid-based monomer used in the method for producing the block copolymer is a glyoxylic acid alkyl ester, and thus has a structure in which an ester group is pendant on the main chain of the block copolymer. The ester itself can be used for various applications described below, but when the obtained block copolymer is further saponified with an alkaline substance to convert the ester group into a group consisting of a carboxylate, it is used in an aqueous system. In this case, the solubility in water is increased, which is preferable.

Specific examples of the alkaline substance include potassium hydroxide, sodium hydroxide and calcium hydroxide.
To trivalent metal hydroxides. One or more of these alkaline substances can be used. The amount of the alkaline substance used is not particularly limited, but is preferably 1.0 to 2.0 (molar ratio) to the glyoxylic acid-based monomer used in the polymerization reaction. More preferably, it is 1.1 to 1.5.

In the saponification reaction, a block copolymer is added to an aqueous solution containing an alkaline substance, and the reaction temperature is from 0 to 100.
C., more preferably at 20-70.degree. A group consisting of a salt of a carboxylic acid having a valence of 1 to 3 obtained by a saponification reaction can be easily converted into a group consisting of an ammonium salt of a carboxylic acid or a group consisting of an amine salt of a carboxylic acid by ion exchange or the like. it can. For example, the salt may be exchanged by mixing a strong acid salt such as an amine hydrochloride, and if necessary, the generated inorganic salt may be removed. Use of Block Copolymer [Cement Dispersant] Cement dispersants include the aforementioned block copolymers.

The block copolymer contained in the cement dispersant is not particularly limited as long as it is the above-mentioned block copolymer, and the block copolymer is composed of a polyalkylene glycol structural unit and a polyglyoxylate structural unit. When the blending ratio [polyalkylene glycol structural unit / polyglyoxylate structural unit (weight ratio)] is 30/70 or more, it is preferable because the addition amount can be reduced and the viscosity can be reduced. Further, it is preferable that the polyalkylene glycol structural unit be a polyethylene glycol structural unit because the solubility in water becomes excellent. Further, the number average molecular weight of the block copolymer contained in the cement dispersant is preferably from 2,000 to 50,000.

The average number of the alkylene glycol structural units constituting the polyalkylene glycol structural units in the block copolymer contained in the cement dispersant, that is, the average value of x in the general formula (1) is not less than 5. If it is not particularly limited, it is preferably 10 to 80 because the fluidity of the cement composition is improved, and more preferably 20 to 60.
It is. The average number of glyoxylate structural units constituting the polyglyoxylate structural unit, that is, the average value of y in the general formula (2) is not particularly limited as long as it is 10 or more. If there is, it is preferable because the addition amount of the cement dispersant can be gradually reduced, and more preferably 20 to 50.

When a cement dispersant is used in a cement composition such as cement mortar or concrete, the dispersibility is improved by the block copolymer, and high fluidity is exhibited without causing a large hardening delay due to the addition. In addition, the mortar construction and concrete construction workability is remarkably improved because the mortar construction and the concrete construction exhibit performance that can extend the pot life. Therefore, this cement dispersant
For example, it can be used as a fluidizer for concrete including ready-mixed concrete. In particular, the production of ready-mixed concrete with a high water reduction ratio as a high-performance AE water reducing agent added simultaneously with a plant can be easily realized.

The cement dispersant can be used for dispersing hydraulic cements such as Portland cement, alumina cement, various mixed cements, and hydraulic materials other than cements such as gypsum. The amount of the cement dispersant added to the cement is not particularly limited, but is preferably 0.01 to 1.0 part by weight based on 100 parts by weight of the cement.

As a method of using the cement dispersant, for example, there is a method of dissolving in kneading water and then adding it at the same time as kneading water when preparing the cement composition, or a method of adding it to the already kneaded cement composition. . Cement dispersants can also be used as high performance water reducing agents for the production of concrete secondary products, reducing water and increasing strength. [Pigment dispersant] The pigment dispersant contains the aforementioned block copolymer.

The block copolymer contained in the pigment dispersant is not particularly limited as long as it is the above-mentioned block copolymer.
The pigment dispersant contains a block copolymer as an essential component,
It may contain other components. Pigment dispersants include kaolin, clay, calcium carbonate, titanium oxide,
It is used to disperse pigments such as barium sulfate, satin white, and magnesium hydroxide in water.

The average number of alkylene glycol structural units constituting the polyalkylene glycol structural units in the block copolymer contained in the pigment dispersant, that is, the average value of x in the general formula (1) is not less than 5. If it is not particularly limited, if it is 5 to 30, the pigment is effectively dispersed,
It is preferable because the viscosity of the slurry containing the pigment can be reduced, and more preferably 8 to 20. Also,
The average number of glyoxylate structural units constituting the polyglyoxylate structural unit, that is, y in general formula (2)
Is not particularly limited as long as it is 10 or more.
When it is from 200 to 200, stability of the viscosity of the slurry containing the pigment over time is improved.
50.

The amount of the pigment dispersant added to the pigment is not particularly limited, but is preferably 0.01 to 1.0 part by weight based on 100 parts by weight of the pigment. The pigment dispersant has excellent dispersibility due to the block copolymer, and has a low viscosity even at a high concentration, so that a dispersion having excellent stability can be prepared. Therefore, it can be particularly preferably used as a dispersant used for dispersing a paper pigment, and can be widely applied in fields such as fiber processing, building material processing, paint, and ceramics. [Water treatment agent] The water treatment agent contains the above-mentioned block copolymer.

The block copolymer contained in the water treatment agent is as follows:
There is no particular limitation as long as it is the aforementioned block copolymer. The water treatment agent contains a block copolymer as an essential component, and may contain other components. The water treatment agent is excellent in chelating ability and scale prevention performance due to the block copolymer, and thus is used for scale prevention in a cooling water system, a boiler system, a seawater desalination apparatus, a pulp digester, a black liquor concentrator, and the like.

The average number of the alkylene glycol structural units constituting the polyalkylene glycol structural units in the block copolymer contained in the water treating agent, that is, the average value of x in the general formula (1) is not less than 5. If it is not particularly limited, it is preferably 5 to 20 because gelation resistance is improved, and more preferably 8 to 18. The average number of glyoxylate structural units constituting the polyglyoxylate structural unit, that is, the average value of y in the general formula (2) is not particularly limited as long as it is 10 or more.
When it is 00, calcium-based scale can be prevented, so that it is more preferably 15 to 50.

The amount of the water treatment agent to be added to water is not particularly limited, but 1 liter of water and 1 to 100 m
g is preferred. [Detergent Builder and Detergent Composition] The detergent builder contains the above-mentioned block copolymer. The detergent builder contains a block copolymer as an essential component, and may further contain components other than the block copolymer, such as other acetal-based polymers and vinyl-based polymers.

The detergent builder, together with a surfactant,
It is a component to be added to the detergent composition described below, and has excellent dispersibility and chelating ability, high cleaning performance, and excellent biodegradability. The detergent builder keeps the pH of the aqueous solution containing the detergent composition constant during washing, captures calcium ions and the like in the aqueous solution, disperses the dirt peeled off from the laundry in the aqueous solution, and removes the dirt from the laundry. It has the function of preventing re-adhesion to objects.

The block copolymer contained in the detergent builder is not limited as long as it is the above-mentioned block copolymer, regardless of whether the form of the detergent composition is a liquid detergent composition or a powder detergent composition. However, when a detergent builder is used for a liquid detergent composition, it is preferable because it has excellent compatibility with the surfactant described below and becomes a highly concentrated liquid detergent composition. When the detergent composition is a liquid detergent composition, the average number of alkylene glycol structural units constituting the polyalkylene glycol structural units in the block copolymer contained in the detergent builder used in the liquid detergent composition, that is, The average value of x in the general formula (1) is not particularly limited as long as it is 5 or more. However, when it is 5 to 20, it is preferable because the mud stain component can be effectively dispersed, and more preferably 8
-18, most preferably 10-15. The average number of glyoxylate structural units constituting the polyglyoxylate structural unit, that is, the average value of y in the general formula (2) is not particularly limited as long as it is 10 or more.
When it is 00, the compatibility with the surfactant is improved, so that it is more preferably 30 to 100, and most preferably 50 to 80.

When the detergent composition is a powder detergent composition, the alkylene glycol structural unit constituting the polyalkylene glycol structural unit in the block copolymer contained in the detergent builder used in the powder detergent composition is used. The average number, that is, the average value of x in the general formula (1) is 5
There is no particular limitation as long as it is above, but when it is 5 to 20, it is preferable because the mud dirt component can be effectively dispersed, more preferably 8 to 18, most preferably 10 to 10.
Fifteen. Further, the average number of glyoxylate structural units constituting the polyglyoxylate structural unit, that is,
The average value of y in the general formula (2) is not particularly limited as long as it is 10 or more, but if it is 30 to 500, it is preferable because the chelating ability is improved, and more preferably, 60 to 40.
0, most preferably 80-400.

In the above, the preferred range of y in the block copolymer contained in the detergent builder is smaller when used as a liquid detergent composition than a powdered detergent composition, because the glyoxylate structural unit is relatively in water. This is because it is difficult to dissolve, and when y is large, it becomes difficult to use it as a liquid detergent composition. Further, the surfactant to be blended in the powder detergent composition,
While mainly anionic surfactants, surfactants incorporated into the liquid detergent composition are mainly nonionic surfactants, and the number of glyoxylate structural units constituting the polyglyoxylate structural unit is This is because, at least, the detergent performance does not decrease.

The detergent composition contains a surfactant and the above-mentioned detergent builder as essential components, and may further contain other components as necessary. The surfactant is at least one selected from an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant, and one or more of these surfactants are used. can do.

Specific examples of the anionic surfactant include:
Alkyl benzene sulfonate, alkyl or alkenyl ether sulfate, alkyl or alkenyl sulfate, α-olefin sulfonate, α-sulfofatty acid or ester salt, alkane sulfonate, saturated or unsaturated fatty acid salt, alkyl or alkenyl ether carboxylate Examples thereof include acid salts, amino acid type surfactants, N-acyl amino acid type surfactants, alkyl and alkenyl phosphates and salts thereof.

Specific examples of the nonionic surfactant include:
Examples thereof include polyoxyalkylene alkyl or alkenyl ether, polyoxyethylene alkyl phenyl ether, higher fatty acid alkanolamide or an alkylene oxide adduct thereof, sucrose fatty acid ester, alkyl glycooxide, fatty acid glycerin monoester, and alkylamine oxide.

Specific examples of the cationic surfactant include:
And quaternary ammonium salts. Specific examples of the amphoteric surfactant include a carboxyl-type or sulfobetaine-type amphoteric surfactant. The mixing ratio of the surfactant contained in the detergent composition is usually from 10 to 60% by weight, preferably from 15 to 60% by weight in the detergent composition.
５０50% by weight. If the blending ratio of the surfactant is less than 10% by weight, sufficient detergent performance cannot be exhibited.
On the other hand, if it exceeds 60% by weight, the economic efficiency is reduced.

The mixing ratio of the builder for detergent contained in the detergent composition is usually 0.1 to 60% by weight, preferably 3 to 30% by weight in the detergent composition. If the compounding ratio of the detergent builder is less than 0.1% by weight, sufficient detergent performance cannot be exhibited. On the other hand, if it exceeds 60% by weight, the economic efficiency is reduced. The detergent composition may contain, if necessary, an enzyme such as a protease, an (alkali) lipase, or an (alkali) cellulase; an alkali builder such as a silicate, a carbonate, or a sulfate; Glycolic acid, oxycarboxylate, EDTA
Chelating builder such as (ethylenediaminetetraacetic acid) and DTPA (diethylenetriaminehexaacetic acid) citric acid; other components such as anti-redeposition agent; fluorescent agent; bleaching agent; fragrance; zeolite; Species or two or more can be used.

As the enzyme, alkaline lipase or alkaline cellulase, which has a high activity in an alkaline washing solution, is preferred. The mixing ratio of the enzyme is usually 0.01 to 5% by weight in the detergent composition. When the blending ratio of the enzyme is 0.
If it is less than 01% by weight, sufficient detergent performance cannot be exhibited. On the other hand, if it exceeds 5% by weight, the economic efficiency is reduced.

The block copolymer is also useful as a binder such as ceramics, a fiber treating agent, a flocculant and the like in addition to the above-mentioned applications.

[0085]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Example A1-80 ml of toluene and polyethylene glycol monomethyl ether (molecular weight: 80 ml) were placed in a glass reactor equipped with a stirrer, a thermometer, a nitrogen gas inlet tube, a condenser, and a dropping funnel.
4,400) 33 g, pyridine as a polymerization catalyst 12 μl
Was supplied. Freshly distilled methyl glyoxylate 35
g was dropped into the reactor over a period of 30 minutes. During the dropwise addition of methyl glyoxylate, the reactor was cooled to control the reaction temperature to about 40 ° C. or lower.

The reaction mixture was cooled to 20 ° C., and 0.03 g of boron trifluoride etherate was added, followed by stirring for 10 minutes to completely dissolve. Then, a mixed solution of 1.0 g of ethylene oxide and 10 ml of toluene was added over 30 minutes. After completion of the addition, stirring was continued for another 60 minutes to produce a stabilized ester polymer. All the above operations were performed in a nitrogen atmosphere in a non-aqueous system.

To the reaction solution containing the obtained stabilized ester polymer was added 1.2 g of methyl glyoxylate used for the polymerization.
The saponification reaction was performed by adding twice the molar amount of sodium hydroxide. A polymer aqueous solution containing a block copolymer 1 was obtained by removing toluene and methanol from the obtained product solution. When the obtained block copolymer 1 was analyzed by gel permeation chromatography (hereinafter abbreviated as GPC), the peak of polyethylene glycol monomethyl ether as a reaction raw material disappeared, and a new peak was recognized on the high molecular weight side. The average molecular weight was 9,000. Further, the measurement results of ¹ H-NMR and IR spectrum of the block copolymer 1 were as follows.

¹ H-NMR (δ value, solvent: heavy water) 3.4 to 3.8 (7H) 4.9 to 5.2 (1H) (The number of protons indicates each ratio.) IR spectrum 2880, 2740, 1630 (carboxylate), 14
30 (carboxylate), 1300, 1110 (ether bond, acetal bond), 940, 840, 680, 5
20 cm ^-1 -Example A2-The amount of methyl glyoxylate used in Example A1 was changed from 35 g to 18 g, and otherwise, Example A was used.
The reaction was carried out in the same manner as in 1 to obtain a polymer aqueous solution containing the block copolymer 2. The obtained block copolymer 2 is G
Analysis by PC revealed that the peak of polyethylene glycol monomethyl ether as a reaction raw material disappeared, and a new peak was observed on the high molecular weight side. Block copolymer 2
Table 1 shows the number average molecular weight of

Example A3- 80 g of toluene, 30 g of polyethylene glycol (molecular weight: 3,000) were placed in a glass reactor equipped with a stirrer, thermometer, nitrogen gas inlet tube, condenser, and dropping funnel.
16 μl of pyridine was supplied as a polymerization catalyst. 55 g of freshly distilled methyl glyoxylate were added dropwise to the reactor over 30 minutes. Hereinafter, the same operation as in Example A1 was performed, and the subsequent operations were performed in the same manner as in Example A1 to obtain a polymer aqueous solution containing the block copolymer 3. When the obtained block copolymer 3 was analyzed by GPC, the peak of polyethylene glycol as a reaction raw material disappeared, and a new peak was recognized on the high molecular weight side. Table 1 shows the number average molecular weight of the block copolymer 3.

-Example A4- The procedure of Example A1 was repeated except that polyethylene glycol monophenyl ether (molecular weight: 1,000) was used instead of polyethylene glycol monomethyl ether, and that the amount of methyl glyoxylate used was changed to 18 g. The reaction was carried out in the same manner as in A1, to obtain a polymer aqueous solution containing the block copolymer 4. When the obtained block copolymer 4 was analyzed by GPC, the peak of polyethylene glycol monophenyl ether as a reaction raw material disappeared, and a new peak was recognized on the high molecular weight side. Table 1 shows the number average molecular weight of the block copolymer 4.

Example A5- In Example A1, polyethylene glycol monoalkyl ether (molecular weight: 500; C12 to C15 in the alkyl group) was used instead of polyethylene glycol monomethyl ether, and methyl glyoxylate was used. The reaction was carried out in the same manner as in Example A1 except that the amount was changed to 18 g, to obtain a polymer aqueous solution containing the block copolymer 5. When the obtained block copolymer 5 was analyzed by GPC, the peak of polyethylene glycol monoalkyl ether as a reaction raw material disappeared, and a new peak was recognized on the high molecular weight side. Table 1 shows the number average molecular weight of the block copolymer 5.

Example A6- Same as Example A1 except that polyethylene glycol mononaphthoxy ether was used in place of polyethylene glycol monomethyl ether and the amount of methyl glyoxylate used was changed to 60 g. To obtain a polymer aqueous solution containing the block copolymer 6. When the obtained block copolymer 6 was analyzed by GPC, the peak of polyethylene glycol mononaphthoxy ether as a reaction raw material disappeared, and a new peak was recognized on the high molecular weight side. Table 1 shows the number average molecular weight of the block copolymer 6.

Comparative Example A1- First, 100 g of methylglyoxylate methyl hemiacetal and 160 g of phosphorus pentoxide were placed in a 500 ml round bottom flask equipped with a stirrer and a heater. The contents of the flask were heated to 100 ° C., stirred for 1 hour, and then cooled to room temperature. The produced aldehyde ester was recovered from the remaining phosphorus pentoxide by distillation and stored in a glass stopper bottle.

Next, 10 g of freshly distilled aldehyde ester obtained above and 100 g of methylene chloride were placed in a 100 ml one-necked round bottom reaction flask equipped with a magnetic stirrer.
ml. The temperature of the contents of the flask was lowered to about 0 ° C., and 5.3 g of ethylene oxide and 0.5 ml of boron trifluoride diethyl etherate were added to initiate polymerization. The flask was placed in an ice bath until the temperature returned to 0-2 ° C (about 45 minutes) and the mixture was stirred at room temperature overnight. About 2 ml of 1N NaOH was added to the mixture and volatiles were removed under vacuum. Thereafter, 12 ml of 2.5N NaOH was added, and the mixture was stirred at about 0 ° C. for about 5 hours, and then stirred at about 40 ° C. for about 24 hours.
Heated for hours. The methanol and residual solvent were removed on a rotary evaporator. The solution was concentrated to about 15%, and a precipitate was formed with about 100 ml of methanol.
Stirred for minutes. The precipitate was collected by filtration, dried, redissolved in distilled water, precipitated in methanol, stirred, and collected by filtration. The yield was about 74.8%. Proton magnetic resonance (PMR)
As a result of spectrum analysis, the product was found to have the following empirical formula:

[0095]

Embedded image

(Here, the average value of n is about 20, and Y is
-CH randomly arranged in the polymer _TwoCH_TwoO-
Yes, p: q = 1: 3. ) Copolymer represented by
(Hereinafter referred to as comparative polymer A1).

[0097]

[Table 1]

Examples in which the block copolymer obtained as described above was used as a cement dispersant, a pigment dispersant, a water treatment agent and a detergent builder will be described below.

Examples B1 and B2 and Comparative Examples B1 and B
2- [Cement dispersant] Block copolymers 1 and 2, Comparative polymer 1 (Naphthalenesulfonic acid formalin condensate Na salt)
Using the comparative polymer A1 as a cement dispersant and the following mortar test, the cement dispersibility was confirmed.

A mortar mixer was charged with 400 g of ordinary Portland cement and 800 g of Toyoura standard sand, and kneaded for 1 minute. Thereafter, 240 g of an aqueous solution in which a predetermined amount of a cement dispersant was dissolved was added and kneaded for 3 minutes to obtain a mortar. The obtained mortar was filled into a hollow cylinder with an inner diameter and height of 50 mm both placed on a glass plate until it was frayed,
This was gently lifted, and the average value of the major axis and minor axis of the spread mortar was defined as the mortar flow value. The higher the mortar flow value, the better the dispersibility. Table 2 shows the results obtained by the mortar test.

[0101]

[Table 2]

As shown in Table 2, the block copolymers 1 to
2 shows that the same mortar flow value was obtained with a smaller amount of addition as compared with Comparative Polymer 1 and Comparative Polymer A1, and it was found that cement dispersion performance was excellent. -Example B3 and Comparative Examples B3 to B4- [Pigment Dispersant] Using block copolymer 1, comparative polymer 2 (sodium polyacrylate (molecular weight 5,000)) and comparative polymer A1 as pigment dispersants, The dispersibility of the pigment was confirmed by measuring the slurry viscosity shown below.

Light calcium carbonate (Brilliant 150)
0: Shiraishi Industry Co., Ltd.) / Water = 60/40 (weight ratio)
Each polymer was added in an amount of 0.3% by weight with respect to calcium carbonate to the slurry prepared so as to obtain a mixture. The mixture was stirred for 3 minutes, and allowed to stand for 1 minute.
M (manufactured by Tokyo Keiki Co., Ltd.). When neither polymer was added, the slurry had no fluidity and viscosity measurement was impossible. The results are shown in Table 3.

[0104]

[Table 3]

Examples B4-B6 and Comparative Examples B5-B
6- [Water-treating agent] Using the block copolymers 1, 4, 5, the comparative polymer 2 and the comparative polymer A1 as the water-treating agent, the following gelation resistance test and measurement of the scale inhibition rate were performed. The performance of the water treatment agent was evaluated. 1) Gelation resistance test: In a glass bottle having a capacity of 225 ml,
100 mg / l aqueous solution of calcium chloride (dihydrate) 100
g was mixed with 1 ml of an aqueous solution (concentration: 1%) of each polymer, and the pH of the test solution was adjusted to 8.5 using NaOH to obtain solution A.

Calcium chloride (dihydrate) 100 mg / l
Using 100 g of pure water as a blank instead of the aqueous solution,
This was mixed with 1 ml of a 1% aqueous polymer solution in the same glass bottle as above, and the solution whose pH was adjusted to 8.5 with NaOH was used as solution B. Seal the above glass bottle and place at 90 ° C for 2
After standing for a time, the absorbance of each solution in the glass bottle with respect to UV 380 nm was measured, and the gelation degree was calculated by the following equation. The smaller the value is, the higher the gelation resistance is, and the drug works effectively. Table 4 shows the obtained results.

Gelation degree = (absorbance of solution A)-(absorbance of solution B) 2) Scale inhibition rate: 170 g of water was placed in a 225 ml glass bottle, and 10 g of a 1.56% calcium chloride (dihydrate) aqueous solution was added. And 3 g of a 0.02% aqueous polymer solution were mixed, and 10 g of a 3% aqueous sodium hydrogen carbonate solution and 7 g of water were added to make the total amount 200 g. The above-mentioned glass bottle was sealed and heat-treated at 70 ° C. for 3 hours. After cooling, the precipitate was filtered through a 0.45 μm membrane filter, and the calcium concentration of the filtrate was measured by ICP analysis. Calcium carbonate scale inhibition rate (%)
I asked. Table 4 shows the obtained results.

Scale inhibition rate (%) = [(Z−Y) /
(X-Y)] × 100, where X: concentration of calcium dissolved in the solution before the test (%) Y: concentration of calcium in the filtrate without the scale inhibitor (%) Z: in the solution after the test Calcium concentration (%)

[0109]

[Table 4]

Examples B7 to B12 and Comparative Examples B7 to
B9- [Detergent Builder and Detergent Composition] Using the block copolymers 1 to 6, Comparative Polymer 3 (diglycolic acid) and Comparative Polymer A1 as detergent builders, the following cleaning performance tests and biodegradability Tests were performed to evaluate the performance of the detergent builder and the performance of the detergent composition containing the polymer. 1) Cleaning performance test: Builder for each detergent (solid content conversion),
A detergent composition was obtained by mixing linear alkylbenzenesulfonic acid sodium salt, No. 2 sodium silicate, anhydrous sodium carbonate and anhydrous sodium sulfate in a weight ratio of 3/25 / 12.5 / 12.5 / 47. .

Further, a stained cloth was prepared by the following method. First, 6.64 g of myristic acid, 6.64 g of oleic acid,
6.64 g of tristearin, 6.64 g of triolein,
After dissolving 0.88 g of cholesterol stearate, 4.40 g of paraffin wax (mp 48 to 50 ° C.), 4.40 g of squalene and 3.52 g of cholesterol in carbon tetrachloride, clay (Kanto loam) (11 kinds of test dust, 39.76 g of carbon black (manufactured by Japan Society of Powder Technology)
Add 0.48 g, and add about 7000 / min
The mixture was stirred for 30 minutes by rotation to prepare two artificial stains. The components other than clay and carbon black used were those of commercially available primary or special grade reagents. Next, using a continuous automatic soiling machine, the test cloth (JIS No. 3 white cotton cloth according to JIS) was contaminated twice with the artificial soil prepared as described above, left at 25 ° C. for 3 weeks, and then 10 cm × 10 cm. To make artificially stained cloth.

Next, the above-prepared 10 cm × 10 cm
8 pieces of the artificially stained cloths were placed in 1 liter of the aqueous solution of the detergent composition prepared above, and washed at 100 rpm with a tergotometer (manufactured by Kamishima Seisakusho) under the following conditions. (Washing conditions): Washing time: 10 minutes Detergent composition concentration: 200 ppm (in terms of sodium linear alkylbenzene sulfonate) Sample: 200 ppm Water hardness: 3 ° DH Water temperature: 25 ° C. Rinsing: 5 minutes with tap water The reflectance of the original cloth before contamination and the contaminated cloth before and after cleaning were measured with a color difference meter, and the evaluation was made by obtaining the cleaning rate by the following equation.

Cleaning rate (%) = (reflectance after cleaning−reflectance before cleaning) / (reflectance of original cloth−reflectance before cleaning) × 10
0 2) Biodegradability test Biodegradability was measured using the modified MIT described in the OECD guidelines.
Evaluation was performed by measuring the biodegradation rate according to the test I (I).

Table 5 shows the results.

[0115]

[Table 5]

[0116]

As described above, the block copolymer of the present invention contains a polyalkylene glycol structural unit represented by the general formula (1) and a polyglyoxylate structural unit represented by the general formula (2). And a novel block copolymer which is excellent in chelating ability, scale prevention performance and the like.

When the structure of at least one terminal of the polymer is selected from the structures represented by the general formulas (3) and (4), the stability of the polymer is increased and the handleability is excellent. Since both the cement dispersant and the pigment dispersant of the present invention contain a block copolymer, they are excellent in dispersibility. Since the water treatment agent of the present invention contains a block copolymer, it has excellent dispersibility, and has excellent chelating ability and scale prevention ability.

Since the detergent builder and the detergent composition of the present invention each contain a block copolymer, they have excellent dispersibility and chelating ability, high washing performance, and excellent biodegradability. The method for producing a block copolymer of the present invention is a polymerization reaction system having a water content of 30 mol% or less with respect to the polyalkylene glycol represented by the general formula (5). Since the glyoxylic acid-based monomer represented by the general formula (6) is subjected to a polymerization reaction, a novel block copolymer excellent in dispersibility, chelating ability and scale prevention performance can be easily prepared. It can be manufactured efficiently.

When the saponification reaction is further carried out with an alkaline substance, the block copolymer becomes more water-soluble, and the effect of water-solubility becomes higher.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shigeru Yamaguchi 5-8 Nishiburi-cho, Suita-shi, Osaka Nippon Shokubai Co., Ltd.

Claims (10)

[Claims] 1. A block copolymer comprising a polyalkylene glycol structural unit represented by the following general formula (1) and a polyglyoxylate structural unit represented by the following general formula (2). Embedded image (However, n is an integer of 2 to 4 and the average value of x is 5 or more.) (Where M is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms,
It is one selected from a monovalent to trivalent metal atom, an ammonium group and an organic amine group, and the average value of y is 10 or more. ) 2. The block copolymer according to claim 1, wherein the structure of at least one terminal of the polymer is selected from the structures represented by the following general formulas (3) and (4). Embedded image (Where n is an integer of 2 to 4, and R ¹ is ^one selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group.) (Where M is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms,
X is one selected from a metal atom having 1 to 3 valences, an ammonium group and an organic amine group, and X is a group which is chemically stable against depolymerization of the block copolymer. ) 3. A cement dispersant comprising the block copolymer according to claim 1. 4. A pigment dispersant comprising the block copolymer according to claim 1. 5. A water treatment agent comprising the block copolymer according to claim 1. 6. A builder for detergents comprising the block copolymer according to claim 1. 7. The detergent builder according to claim 6, which is used for a liquid detergent composition. 8. A detergent composition comprising a surfactant and the detergent builder according to claim 6 as essential components, wherein the surfactant is an anionic surfactant, a nonionic surfactant, At least one selected from a cationic surfactant and an amphoteric surfactant, wherein the surfactant is 10 to 60% by weight and the detergent builder is 0.1 to 60% by weight in the detergent composition. A detergent composition, characterized in that: 9. A polymerization reaction system having a water content of 30 mol% or less with respect to a polyalkylene glycol represented by the following general formula (5), wherein the polyalkylene glycol is added with the following general formula (6) in the presence of a catalyst. A method for producing a block copolymer, comprising subjecting a glyoxylic acid-based monomer represented by the following to a polymerization reaction. Embedded image (However, R ¹ is ^one selected from a hydrogen atom, an alkyl group, an alkenyl group, an alkylphenyl group, a phenyl group and a benzyl group, n is an integer of 2 to 4, and the average value of x is 5 or more. )) (However, R ² is an alkyl group having 1 to 4 carbon atoms.) 10. The method for producing a block copolymer according to claim 9, wherein a saponification reaction is further carried out with an alkaline substance.