JP2010065145A - Multi-branched polyalkylene glycol-based polymer and method for producing the same, cement admixture and cement composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-branched polyalkylene glycol-based polymer useful for various uses, especially cement admixture uses, to provide a cement admixture using the same, to provide a cement composition using the same, and to provide a method for producing the multi-branched polyalkylene glycol-based polymer, by which the multi-branched polyalkylene glycol-based polymer can simply and efficiently be produced at a low cost. <P>SOLUTION: There is provided the multi-branched polyalkylene glycol-based polymer containing a polyalkylene glycol chain and having a multi-branched structure, characterized in that the polymer has a structure in which the polyalkylene glycol chain is bound to the residue of a compound having three or more active hydrogen atoms, and a terminal oxygen atom at at least one of the other ends of the polyalkylene glycol chain is bound to the main chain terminal of a polymer containing constituting units originated from a vinylic monomer component through an organic residue. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a multi-branched polyalkylene glycol polymer, a method for producing the same, a cement admixture, and a cement composition. More specifically, multi-branched polyalkylene glycol polymers used in various applications such as cement admixtures, adhesives and sealants, softening ingredients, detergent builders as soft segments, and the like. The present invention relates to a cement admixture and a cement composition obtained as described above, and a method for producing such a polymer.

A polymer containing a polyalkylene glycol chain is imparted with characteristics such as hydrophilicity, hydrophobicity, and steric repulsion by appropriately adjusting the chain length and the alkylene oxide constituting the polymer, and is used as an adhesive or a sealing agent as a soft segment. It is widely used in various applications such as a softening component application and a detergent builder application.
In recent years, the use of cement admixtures added to cement compositions such as cement paste, mortar and concrete has been studied. Such a cement admixture is usually used as a water reducing agent or the like, and exerts an effect of improving the strength and durability of the cured product by reducing the cement composition by increasing the fluidity of the cement composition. Used for that purpose. As a water reducing agent, a water reducing agent such as naphthalene has been conventionally used, but the polyalkylene glycol chain can act as a dispersing group for dispersing cement particles due to its steric repulsion, and therefore contains a polyalkylene glycol chain. The polycarboxylic acid-based water reducing agent has been newly proposed as exhibiting a high water reducing action, and has recently been used as a high-performance AE water reducing agent.

With respect to a polymer containing a conventional polyalkylene glycol chain, for example, both ends obtained by decomposing a thioester group formed after adding a thiocarboxylic acid to a polyether having a double bond at both ends or one end A polyether having a mercapto group at one end (for example, see Patent Document 1) or a compound having a mercapto group as a biodegradable water-soluble polymer used in a detergent builder is introduced into a polyether compound by an ester reaction. A polymer obtained by subjecting a modified polyether compound to block or graft polymerization of a monoethylene biounsaturated monomer component is disclosed (for example, see Patent Document 2). Further, it is disclosed that a novel polymer having a polymer unit comprising a polyalkylene glycol chain and a constituent unit derived from an unsaturated monomer bonded to at least one end of the chain is particularly useful as a cement admixture. (For example, refer to Patent Document 3).

However, a polymer containing a conventional polyalkylene glycol chain has not yet reached a level that can sufficiently exhibit the extremely high degree of cement dispersibility (water-reducing property) that has recently been demanded. Therefore, there has been room for devising to make the compound useful in more fields by making it suitable for use as a cement admixture. In addition, there is room for improvement in order to produce such a polymer having high cement dispersibility more easily and efficiently at a low cost.
Japanese Patent Publication No. 7-13141 JP-A-7-109487 JP 2007-119736 A

The present invention has been made in view of the above situation, and is useful for various uses, particularly for cement admixtures, a multi-branched polyalkylene glycol polymer, a cement admixture and a cement composition using the same, It is an object of the present invention to provide a production method capable of producing a branched polyalkylene glycol-based polymer simply and efficiently at a low cost.

The inventors of the present invention have made various studies on polymers containing polyalkylene glycol chains, and pay attention to the fact that, when a structure having a multi-branched structure is used, high water reduction performance can be exerted on cement compositions and the like due to steric repulsion. A polyalkylene glycol chain bonded to the residue of a compound having 3 or more active hydrogens, and at least one terminal oxygen atom at the other end of the chain is a heavy chain containing a structural unit derived from a vinyl-based monomer component. While a polymer having a structure in which the main chain end of the coalescence is bonded via an organic residue can provide a cement admixture that exhibits excellent dispersion performance, the polymer has been known so far. It was found that the polymer was a novel compound and was useful in many fields. Further, a polymer obtained by polymerizing a vinyl monomer component in the presence of a compound having a polyalkylene glycol chain bonded to a residue of a compound having 3 or more active hydrogens and bonded to an organic residue is also provided. In addition, it is found that the compound is a novel compound capable of exhibiting excellent dispersibility, and also that such a production method is found to be a very useful technique industrially, and can solve the above-mentioned problems brilliantly. I came up with what I can do.

Furthermore, among such polymers, a polymer in which the organic residue interposed between the terminal hydrogen atom of the polyalkylene glycol chain and the main chain end of the polymer is a group containing a sulfur atom is efficient and simple. In addition, it has been found that it can be produced at a low cost and that it can fully exhibit the effect of exhibiting excellent dispersion performance. Such a polymer is a vinyl monomer in the presence of a compound having a polyalkylene glycol chain bonded to a residue of a compound having 3 or more active hydrogens and bonded to an organic residue containing a sulfur atom. Can be obtained by polymerizing the components, but whether radicals generated from the mercapto group by heat, light, radiation, etc., or radicals generated by a polymerization initiator used separately as necessary, chain transfer to the mercapto group Alternatively, when the mercapto groups are bonded to each other to form a disulfide bond, the disulfide bond is cleaved, and monomers are successively added via the sulfur atom (S), thereby the polymer. It seems to give the structure of
And, the cement admixture obtained by using the polymer of the present invention has been found to be able to exhibit dispersibility as never before, and the cement composition comprising the same has been found to be particularly useful in the field. The present invention has been achieved.

That is, the present invention is a polymer having a polyalkylene glycol chain and having a multi-branched structure, wherein the polymer is bonded to a residue of a compound in which the polyalkylene glycol chain has 3 or more active hydrogens, and A polybranched poly having a structure in which a terminal oxygen atom at at least one other end of a polyalkylene glycol chain is bonded to a main chain end of a polymer containing a structural unit derived from a vinyl monomer component via an organic residue It is an alkylene glycol polymer.
The present invention is described in detail below.

<Multi-branched polyalkylene glycol polymer>
The multi-branched polyalkylene glycol-based polymer of the present invention binds to a residue of a compound in which the polyalkylene glycol chain has three or more active hydrogens, and a terminal oxygen atom at at least one other end of the polyalkylene glycol chain However, it has the structure couple | bonded via the organic residue with the principal chain terminal of the polymer containing the structural unit derived from a vinyl-type monomer component.
Hereinafter, the multi-branched polyalkylene glycol polymer of the present invention is referred to as “polymer (i)”, and the structural unit derived from the vinyl monomer component in which the polyalkylene glycol chain is bonded through an organic residue. A polymer containing is also referred to as “polymer (ii)”.

The polymer (i) has a multi-branched structure, and the multi-branched structure here means a structure branched radially from the residue of a compound having 3 or more active hydrogens. . That is, it means a structure in which the polymer (ii) is bonded from a residue of a compound having 3 or more active hydrogens as a starting point through a polyalkylene glycol chain and an organic residue. The polymer of the present invention having such a multi-branched structure is particularly excellent in cement dispersion performance and has a possibility of being applicable to various fields in the future because it is a novel polymer.

In the polymer (i), the residue of the compound having active hydrogen means the group having a structure in which active hydrogen is removed from the compound having active hydrogen, Active hydrogen means hydrogen to which alkylene oxide can be added. The number of residues of such compounds having 3 or more active hydrogens may be one, or two or more.

The number of active hydrogens of the compound having active hydrogens is suitably 3 or more from the viewpoint of industrial production efficiency, and the polymerization is carried out using the polyalkylene glycol chain-containing thiol compound. From the viewpoint of properties, the number is preferably 50 or less. The lower limit value of the number of active hydrogens is preferably 4, more preferably 5, and the upper limit value is more preferably 20, more preferably 10.

Specific examples of the residue of the compound having three or more active hydrogens include, for example, polyhydric alcohol residues having a structure in which active hydrogen is removed from the hydroxyl group of the polyhydric alcohol, and active from the amino group of the polyvalent amine. A polyvalent amine residue having a structure excluding hydrogen, a polyvalent imine residue having a structure in which active hydrogen is removed from an imino group of a polyvalent imine, and a structure in which active hydrogen is removed from an amide group of a polyvalent amide compound Multivalent amide residues and the like are preferred. Of these, polyvalent amine residues, polyalkyleneimine residues and polyhydric alcohol residues are preferred. That is, the residue of the compound having three or more active hydrogens is at least one polyvalent compound residue selected from the group consisting of a polyvalent amine residue, a polyalkyleneimine residue, and a polyhydric alcohol residue. Preferably it is. This makes it possible to obtain a compound suitable for various applications.
The form of the compound residue having active hydrogen may be any of a chain, branched, and three-dimensionally crosslinked structure.

In a preferred form of the residue of the compound having active hydrogen, the polyvalent amine (polyamine) may be a compound having an average of 3 or more amino groups in one molecule, for example, methylamine, ethylamine, propyl Alkylamines such as amine, butylamine, 2-ethylbutylamine, octylamine, dimethylamine, dipropylamine, dimethylethanolamine, dibutylamine, trimethylamine, triethylamine, cyclobutylamine, cyclohexylamine, laurylamine; alkyleneamines such as allylamine; aniline Homopolymers and copolymers obtained by polymerizing one or more monoamine compounds such as aromatic amines such as diphenylamine; nitrogen compounds such as ammonia, urea, and thiourea by a conventional method are suitable. . By such a compound, the polyvalent amine residue of the polyalkylene glycol chain-containing thiol compound is formed. Further, it may be ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, tripropylenetetramine, tetrapropylenepentamine, and the like. In addition to the primary amino group, it has a primary amino group having an active hydrogen atom or a secondary amino group (imino group).
Among these, it is preferable to use a polyalkylamine. As the alkylamine constituting the polyalkylamine, an alkylamine having 8 to 18 carbon atoms such as laurylamine is preferable.

The polyalkyleneimine may be a compound having an average of 3 or more imino groups in one molecule, such as ethyleneimine, propyleneimine, 1,2-butyleneimine, 2,3-butyleneimine, 1 A homopolymer or a copolymer obtained by polymerizing one or more alkylene imines having 2 to 8 carbon atoms such as 1-dimethylethyleneimine by a conventional method is preferable. By such a compound, the polyalkyleneimine residue of the polyalkylene glycol chain-containing thiol compound is formed. Polyalkyleneimine is three-dimensionally cross-linked by polymerization, and usually has a tertiary amino group, a primary amino group having an active hydrogen atom, or a secondary amino group (imino group) in the structure. become.
Among these, from the viewpoint of performance exhibited by the polyalkylene glycol chain-containing thiol compound, a polyalkyleneimine mainly composed of ethyleneimine is more preferable.

The “main body” in this case means that when the polyalkyleneimine is formed by two or more kinds of alkyleneimines, it accounts for the majority of the total number of alkyleneimines present. In the present invention, the alkyleneimine forming the polyalkyleneimine chain is mostly ethyleneimine, so that the hydrophilicity of the polyalkyleneglycol chain-containing thiol compound is improved and suitable for many applications. From the fact that the action and effect are sufficiently exhibited, by using ethyleneimine as an alkyleneimine that forms a polyalkyleneimine chain (polyalkyleneimine residue) to the extent that the above action and effect are sufficiently exhibited, It will be “occupying the majority” mentioned above. When “dominating” is expressed in terms of mol% of ethyleneimine in 100 mol% of all alkyleneimines, it is preferably 50 to 100 mol%. If it is less than 50 mol%, the hydrophilicity of the polyalkyleneimine chain may not be sufficient. More preferably, it is 60 mol% or more, More preferably, it is 70 mol% or more, Especially preferably, it is 80 mol% or more, Most preferably, it is 90 mol% or more.

The average polymerization number of the alkyleneimine per one polyalkyleneimine chain is preferably 2 or more, and preferably 300 or less. By setting it in such a range, it becomes possible to more fully exert the action and effect resulting from the structure of the polyalkylene glycol chain-containing thiol compound. For example, the cement admixture etc. It can be made suitable for. As a lower limit, More preferably, it is 3, More preferably, it is 5, Especially preferably, it is 10. Moreover, as an upper limit, More preferably, it is 200, More preferably, it is 100, Especially preferably, it is 50, Most preferably, it is 25. The average polymerization number of diethylenetriamine is 2, and the average polymerization number of triethylenetetramine is 3.

As a number average molecular weight of the said polyvalent amine and polyalkyleneimine, 100-100000 are preferable, More preferably, it is 300-50000, More preferably, it is 600-10000, Most preferably, it is 800-5000.

The polyhydric alcohol may be a compound containing an average of 3 or more hydroxyl groups in one molecule, but is preferably a compound composed of three elements of carbon, hydrogen and oxygen. Specifically, for example, polyglycidol, glycerin, polyglycerin, trimethylolethane, trimethylolpropane, 1,3,5-pentatriol, erythritol, pentaerythritol, dipentaerythritol, sorbitol, sorbitan, sorbitol glycerin condensate, Adonitol, arabitol, xylitol, mannitol and the like are preferable. Moreover, as sugars, saccharides of hexoses such as glucose, fructose, mannose, indoses, sorbose, growth, talose, tagatose, galactose, allose, psicose, altrose; arabinose, ribulose, ribose, xylose, xylulose, lyxose, etc. Saccharides of pentoses; saccharides of tetroses such as treose, erythrulose, erythrose; other saccharides such as rhamnose, cellobiose, maltose, isomaltose, trehalose, sucrose, raffinose, gentianose, melezitose; these sugar alcohols, sugar acids ( Saccharides; glucose, sugar alcohols; glucite, sugar acids; gluconic acids) and the like are also suitable. Furthermore, derivatives such as partially etherified products and partially esterified products of these exemplified compounds are also suitable. By such a compound, the polyhydric alcohol residue of the polyalkylene glycol chain-containing thiol compound is formed.
Among these, trimethylolpropane and sorbitol are more preferable from the viewpoint of industrial production efficiency.

The residue of the compound having 3 or more active hydrogens is bonded to a polyalkylene glycol chain bonded to the polymer (ii) via 2 or more organic residues. That is, the number of the polyalkylene glycol chains to which the compound having 3 or more active hydrogens is bonded is suitably 2 or more. In this case, the polymer (i) of the present invention has the above-described multi-branched structure. Preferably, it is 3 or more.
The number of the polyalkylene glycol chains to which the compound having 3 or more active hydrogens is bonded is preferably equal to the number of active hydrogens in the compound having 3 or more active hydrogens. That is, it is preferable to have a structure in which a polyalkylene glycol chain is bonded to all active hydrogen atoms in the compound having three or more active hydrogens. This makes it possible to provide a cement admixture that can exhibit further superior dispersibility, so that the compound can be applied to various applications.

Here, when schematically showing the structure in which the number of the polyalkylene glycol chains to which the compound having 3 or more active hydrogens is bonded is equal to the number of active hydrogens in the compound having 3 or more active hydrogens, It can be expressed as follows:
In the following formula (A), the residue of the compound having 3 or more active hydrogens is a glycerin residue (polyhydric alcohol residue), and all the active hydrogens possessed by glycerin include a polyalkylene glycol chain and a sulfur atom. 1 schematically shows a structure in which a polymer (ii) is bonded through an organic residue.
In the following formula (B), the residue of the compound having 3 or more active hydrogens is a sorbitol residue (polyhydric alcohol residue), and all the active hydrogens possessed by sorbitol have a polyalkylene glycol chain and a sulfur atom. 1 schematically shows a structure in which a polymer (ii) is bonded through an organic residue containing it.

In the multi-branched polyalkylene glycol polymer (i), a polyalkylene glycol chain is bonded to the residue of the compound having three or more active hydrogens.
The polyalkylene glycol chain may be any one composed of an alkylene oxide having 2 or more carbon atoms (polyalkylene oxide), and the alkylene oxide is preferably an alkylene oxide having 2 to 18 carbon atoms. More preferably, it is an alkylene oxide having 2 to 8 carbon atoms, such as ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, trimethylethylene oxide, tetramethylene oxide, tetramethylethylene oxide, butadiene. Examples include monooxide and octylene oxide. In addition, aliphatic epoxides such as dipentane ethylene oxide and dihexane ethylene oxide; alicyclic epoxides such as trimethylene oxide, tetramethylene oxide, tetrahydrofuran, tetrahydropyran, and octylene oxide; aromatics such as styrene oxide and 1,1-diphenylethylene oxide Epoxides and the like can also be used.

The alkylene oxide constituting the polyalkylene glycol chain is preferably selected as appropriate according to the use required for the polymer (i) of the present invention. For example, when used for the production of a cement admixture component. From the viewpoint of affinity with cement particles, it is preferable that the main component is a relatively short chain alkylene oxide (oxyalkylene group) having about 2 to 8 carbon atoms. More preferably, the main component is an alkylene oxide having 2 to 4 carbon atoms such as ethylene oxide, propylene oxide, butylene oxide, and still more preferably, the main component is ethylene oxide.

The “main body” as used herein means that when the polyalkylene glycol chain is composed of two or more types of alkylene oxides, it accounts for the majority of the total number of alkylene oxides present. When “dominating” is expressed in terms of mol% of ethylene oxide in 100 mol% of all alkylene oxides, 50 to 100 mol% is preferable. Thereby, the polymer (i) has higher hydrophilicity. More preferably, it is 60 mol% or more, More preferably, it is 70 mol% or more, Especially preferably, it is 80 mol% or more, Most preferably, it is 90 mol% or more.

When the polyalkylene glycol chain is composed of two or more types of alkylene oxides, two or more types of alkylene oxides may be added in any form such as random addition, block addition, alternating addition, etc. When a plurality of the polyalkylene glycol chains are present in one molecule of the polymer (i), these may be the same or different.

When the polyalkylene glycol chain contains an alkylene oxide having 3 or more carbon atoms, it becomes possible to impart a certain degree of hydrophobicity to the polymer (i). When used as a cement admixture, it gives some structure (network) to the cement particles, and can reduce the viscosity and stiffness of the cement composition. On the other hand, if the alkylene oxide having 3 or more carbon atoms is introduced too much, the hydrophobicity of the polymer (i) becomes too high, so that the performance of dispersing cement particles may not be sufficient. For this reason, it is preferable that content of C3 or more alkylene oxide with respect to 100 mass% of all alkylene oxides is 30 mass% or less. More preferably, it is 25 mass% or less, More preferably, it is 20 mass% or less, Most preferably, it is 5 mass% or less.
In addition, depending on the use requested | required of the said polymer (i), the aspect which does not contain C3 or more alkylene oxide may be preferable.

The average number of repeating alkylene oxides in the polyalkylene glycol chain (average number of moles of oxyalkylene group added) is preferably 5 to 1,000. By setting the number to 5 or more, the polymer (i) can sufficiently exhibit the performance based on the polyalkylene glycol chain, and when n exceeds 1000, the polymer (i) There is a possibility that the viscosity of the raw material compound used for producing the product may not be suitable from the viewpoint of workability, for example, the reactivity may not be sufficient. The lower limit value of the average number of repetitions is more preferably 7, more preferably 10, and the upper limit value is more preferably 800, still more preferably 600.
The average number of repeating alkylene oxides (average number of moles of oxyalkylene group added) is the average number of moles of alkylene oxide added in 1 mole of the polyalkylene glycol chain of the polymer (i). Means.

In the multi-branched polyalkylene glycol polymer (i), the terminal oxygen atom at at least one other terminal of the polyalkylene glycol chain is connected to the main chain terminal of the polymer (ii) via an organic residue. Will be combined.
The organic residue is preferably a group having a molecular weight of 1000 or less. If it exceeds 1000, the group itself is easily hydrolyzed, and there is a possibility that the polymer (ii) cannot be stably bonded to the polyalkylene glycol chain, and the introduction of the group becomes difficult, Economic efficiency may be impaired. More preferably, it is 500 or less, More preferably, it is 300 or less.

The organic residue also preferably contains a sulfur atom, and specifically includes, for example, —S—Y ² —COO—, —S—Y ² —CO—, and —S—Y ² —. CO—NH—, —S—Y ² —CO—NH—CH ₂ —CH ₂ —, —S—Y ² —, —S—Y ² —O—, —S—Y ² —N—, —S— Y ² —S— or the like is preferable. Here, Y ² is a divalent organic residue, preferably a linear, branched or cyclic alkylene group having 1 to 18 carbon atoms or an aromatic group (phenyl group) having 6 to 11 carbon atoms. Alkylphenyl group, pyridinyl group, thiophene, pyrrole, furan, thiazole, etc.), for example, hydroxyl group, amino group, acetylamino group, cyano group, carbonyl group, carboxyl group, halogen group, sulfonyl group, nitro group , A group which may be partially substituted with a substituent such as a formyl group.
Thus, when the organic residue has a sulfur atom, it is preferable that the main chain end of the polymer (ii) is bonded via the sulfur atom. In such a form, as will be described later, at the time of production, monomers are successively added via sulfur atoms due to the reactivity of sulfur atoms to form polymer (ii) sites. Therefore, it is advantageous for manufacturing.

Among the organic residues containing a sulfur atom, those containing a carbonyl group (—C (O) —) or an amide group (—N (H) —C (O) —) are preferred. A form in which the residue contains a carbonyl group or an amide group is also one of the preferred forms of the present invention. Such a form is useful for industrial production because it is easy to manufacture and can be manufactured at low cost.
In this case, the carbon atom contained in the carbonyl group (including the —CO group in the amide group) and the terminal oxygen atom of the polyalkylene glycol chain are adjacent to each other at the bonding site between the organic residue and the polyalkylene glycol chain. It is preferable to do. That is, the polymer (i) is preferably one in which a polyalkylene glycol chain and Y ² are bonded via an ester bond or an amide bond.

The polymer (ii) may be one kind of polymer or a mixture of two or more kinds of polymers. It is preferable to contain a saturated carboxylic acid monomer as an essential component. Thereby, the hydrophilicity of a polymer is improved and it becomes possible to make it useful by various uses. Moreover, when using it for uses, such as a cement admixture, in order to improve dispersibility further, it is suitable for the said vinyl-type monomer component to contain an unsaturated polyalkylene glycol-type monomer. In this case, the steric repulsion resulting from the polybranched structure is added to the steric repulsion of the polyalkylene glycol chain derived from the unsaturated polyalkylene glycol-based monomer. It is thought to improve dramatically. More preferably, the vinyl monomer component includes an unsaturated carboxylic acid monomer (a) and an unsaturated polyalkylene glycol monomer (b). That is, the polymer (ii) is a form containing a structural unit derived from the unsaturated carboxylic acid monomer (a) and a structural unit derived from the unsaturated polyalkylene glycol monomer (b). Is preferred.

Examples of the unsaturated carboxylic acid monomer (a) (hereinafter also simply referred to as “monomer (a)”) include, for example, the following formula (1);

^(Wherein, R 1, ^{R 2} and ^{R 3} are the same or different and each represents a hydrogen atom, a methyl group or _{(CH ²⁾} x COOM _{2 Note, -. (CH 2) x} COOM 2 is -COOM ¹ Or other — (CH ₂ ) _x COOM ² may form an anhydride, x is an integer of 0 to ^2. M ¹ and M ² are the same or different and are a hydrogen atom, monovalent Represents a metal, divalent metal, trivalent metal, quaternary ammonium base or organic amine base).
The structural unit derived from the monomer (a) is a structure in which a polymerizable double bond of the monomer (a) represented by the general formula (1) is opened by a polymerization reaction (double bond (C = C) corresponds to a single bond (-C—C—).

In the general formula (1), examples of the metal atom represented by M ¹ and M ² include monovalent metal atoms such as alkali metal atoms such as lithium, sodium and potassium; alkaline earth metals such as calcium and magnesium And divalent metal atoms such as atoms; trivalent metal atoms such as aluminum and iron. Examples of the organic amine base include alkanolamine groups such as ethanolamine group, diethanolamine group and triethanolamine group, and triethylamine group.

Specific examples of the unsaturated carboxylic acid monomer represented by the general formula (1) include monocarboxylic acid monomers such as acrylic acid, methacrylic acid, and crotonic acid; maleic acid, itaconic acid, and fumaric acid. Dicarboxylic acid monomers such as acids; anhydrides or salts of these carboxylic acids (for example, alkali metal salts, alkaline earth metal salts, trivalent metal salts, ammonium salts, organic amine salts) and the like. Among these, acrylic acid, methacrylic acid, maleic acid, maleic anhydride and salts thereof are preferable from the viewpoint of polymerizability, and acrylic acid, methacrylic acid and salts thereof are more preferable.

Examples of the unsaturated polyalkylene glycol monomer (b) (hereinafter also simply referred to as “monomer (b)”) include, for example, the following formula (2);

(.AO ^wherein, R 4, ^{R 5} and ^{R 6} are the same or different, .R ⁷ represents a hydrogen atom or a methyl group, represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms are the same Or, differently, it represents one or more of oxyalkylene groups having 2 to 18 carbon atoms, and when there are two or more oxyalkylene groups represented by AO, these groups are introduced in a block form. And y is an integer of 0 to 2. z is 0 or 1. r represents the average number of moles added of the oxyalkylene group. A number of 300.) is preferred.
The structural unit derived from the monomer (b) is a structure in which a polymerizable double bond of the monomer (b) represented by the general formula (2) is opened by a polymerization reaction (double bond (C = C) corresponds to a single bond (-C—C—).

In the general formula (2), of the terminal group represented by ^{R 7,} examples of the hydrocarbon group having 1 to 20 carbon atoms, aliphatic alkyl group having 1 to 20 carbon atoms, alicyclic of 3 to 20 carbon atoms Examples thereof include an alkyl group having 2 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms.
The terminal group represented by R ⁷ is preferably a hydrophilic group from the viewpoint of dispersibility of cement particles when used for cement admixture, specifically, a hydrogen atom or carbon. The hydrocarbon group of number 1-8 is preferable. More preferably, they are a hydrogen atom or a C1-C6 hydrocarbon group, More preferably, they are a hydrogen atom or a C1-C3 hydrocarbon group, Most preferably, they are a hydrogen atom or a methyl group.

In the general formula (2), the polyalkylene glycol chain represented by (AO) _r is preferably composed mainly of oxyethylene groups having 2 carbon atoms (ethylene oxide). Thereby, the obtained polymer (ii) becomes sufficiently hydrophilic, and sufficient water solubility and cement particle dispersion performance are imparted to the multi-branched polyalkylene glycol polymer of the present invention.
Here, “mainly” means, for example, 50 to 100 mol% when oxyethylene groups in 100 mol% of all oxyalkylene groups (alkylene glycol units) constituting the polyalkylene glycol chain are expressed in mol%. It is preferable that If it is less than 50 mol%, the hydrophilicity of the oxyalkylene group may not be sufficient, and the dispersion performance of cement particles may not be sufficiently imparted. More preferably, it is 60 mol% or more, More preferably, it is 70 mol% or more, Especially preferably, it is 80 mol% or more, Most preferably, it is 90 mol% or more.

The polyalkylene glycol chain represented by the above (AO) _r may also contain a oxyalkylene group having 3 or more carbon atoms having higher hydrophobicity as a part thereof. When such a hydrophobic group is introduced, when used as a cement admixture (dispersant), the viscosity of the cement composition is adjusted by showing a light hydrophobic interaction between polyalkylene glycol chains in an aqueous solution. This is because workability may be improved. When introducing an oxyalkylene group having 3 or more carbon atoms, the amount introduced is, for example, to maintain sufficient water solubility with respect to 100 mol% of all oxyalkylene groups (alkylene glycol units) constituting the polyalkylene glycol chain. Is preferably 50 mol% or less. More preferably, it is 25 mol% or less, More preferably, it is 10 mol% or less. Moreover, it is preferable that it is 1 mol% or more for improvement of workability | operativity. More preferably, it is 2.5 mol% or more, More preferably, it is 5 mol% or more.
As the oxyalkylene group having 3 or more carbon atoms, a propylene oxide group and a butylene oxide group are preferable from the viewpoint of ease of production, and among them, a propylene oxide group is more preferable.

When the polyalkylene glycol chain is composed of an oxyethylene group having 2 carbon atoms and an oxyalkylene group having 3 or more carbon atoms, these sequences may be random or block, When the block arrangement is used, the hydrophilicity of the hydrophilic block is expressed more strongly than the random arrangement, and the hydrophobicity of the hydrophobic block seems to be expressed more strongly. This is preferable because workability is further improved. In particular, it is preferably arranged in an ABA block shape as (oxygen group having 2 carbon atoms)-(oxyalkylene group having 3 or more carbon atoms)-(oxyethylene group having 2 carbon atoms).

In the general formula (2), r is a number of 1 to 300, but if it exceeds 300, there is a risk of production failure, and the viscosity of the cement composition when used as a cement admixture is low. The workability may not be sufficient due to the increase. From the viewpoint of production, r is suitably 300 or less, preferably 200 or less, more preferably 150 or less, still more preferably 100 or less, particularly preferably 75 or less, and most preferably 50 or less. Further, from the viewpoint of strongly dispersing cement particles, r is preferably 4 or more. More preferably, it is 6 or more, More preferably, it is 10 or more, Most preferably, it is 25 or more.

Specific examples of the unsaturated polyalkylene glycol monomer represented by the general formula (2) include an unsaturated alcohol polyalkylene glycol adduct and a polyalkylene glycol ester monomer.
The unsaturated alcohol polyalkylene glycol adduct may be a compound having a structure in which a polyalkylene glycol chain is added to an alcohol having an unsaturated group.
The polyalkylene glycol ester monomer may be a monomer having a structure in which an unsaturated group and a polyalkylene glycol chain are bonded via an ester bond. The unsaturated carboxylic acid polyalkylene glycol ester monomer Compounds are preferred, among which (alkoxy) polyalkylene glycol mono (meth) acrylates are preferred.

Examples of the unsaturated alcohol polyalkylene glycol adduct include vinyl alcohol alkylene oxide adduct, (meth) allyl alcohol alkylene oxide adduct, 3-buten-1-ol alkylene oxide adduct, isoprene alcohol (3-methyl- 3-buten-1-ol) alkylene oxide adduct, 3-methyl-2-buten-1-ol alkylene oxide adduct, 2-methyl-3-buten-2-ol alkylene oxide adduct, 2-methyl-2 -Butene-1-ol alkylene oxide adducts and 2-methyl-3-buten-1-ol alkylene oxide adducts are preferred.

Specific examples of the unsaturated alcohol polyalkylene glycol adduct include, for example, polyethylene glycol monovinyl ether, polyethylene glycol monoallyl ether, polyethylene glycol mono (2-methyl-2-propenyl) ether, polyethylene glycol mono (2-butenyl). Ether, polyethylene glycol mono (3-methyl-3-butenyl) ether, polyethylene glycol mono (3-methyl-2-butenyl) ether, polyethylene glycol mono (2-methyl-3-butenyl) ether, polyethylene glycol mono (2- Methyl-2-butenyl) ether, polyethylene glycol mono (1,1-dimethyl-2-propenyl) ether, polyethylene polypropylene glycol mono (3-methyl-3-butene) Nyl) ether, methoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, ethoxy polyethylene glycol mono (3-methyl-3-butenyl) ether, 1-propoxy polyethylene glycol mono (3-methyl-3-butenyl) ether , Cyclohexyloxypolyethylene glycol mono (3-methyl-3-butenyl) ether, phenoxypolyethyleneglycolmono (3-methyl-3-butenyl) ether, methoxypolyethyleneglycolmonoallylether, ethoxypolyethyleneglycolmonoallylether, phenoxypolyethyleneglycolmono Allyl ether, methoxypolyethylene glycol mono (2-methyl-2-propenyl) ether, ethoxypolyethylene glycol mono (2-methyl -2-propenyl) ether, phenoxy polyethylene glycol mono (2-methyl-2-propenyl) ether and the like.

Examples of the (alkoxy) polyalkylene glycol mono (meth) acrylate include, for example, alkoxypolyalkylene glycols obtained by adding 1 to 25 moles of an alkylene oxide group having 2 to 18 carbon atoms to alcohols, particularly alkoxypolyethylene mainly composed of ethylene oxide. An esterified product of an alkylene glycol and (meth) acrylic acid is preferred.
Examples of the alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, and 2-hexanol. Aliphatic alcohols having 1 to 30 carbon atoms such as 3-hexanol, octanol, 2-ethyl-1-hexanol, nonyl alcohol, lauryl alcohol, cetyl alcohol, stearyl alcohol; fats having 3 to 30 carbon atoms such as cyclohexanol Cyclic alcohols; unsaturated alcohols having 3 to 30 carbon atoms such as (meth) allyl alcohol, 3-buten-1-ol, 3-methyl-3-buten-1-ol, and the like.

Specifically, the following (alkoxy) polyethylene glycol (poly) (C2-C4 alkylene glycol) (meth) acrylic acid esters and the like are preferable as the esterified product.
Methoxy polyethylene glycol mono (meth) acrylate, methoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, methoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, methoxy {polyethylene glycol (poly) propylene glycol (Poly) butylene glycol} mono (meth) acrylate, ethoxypolyethylene glycol mono (meth) acrylate, ethoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, ethoxy {polyethylene glycol (poly) butylene glycol} mono (meta ) Acrylate, ethoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (Meth) acrylate, propoxy polyethylene glycol mono (meth) acrylate, propoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, propoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, propoxy {polyethylene glycol ( Poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate,

Butoxy polyethylene glycol mono (meth) acrylate, butoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, butoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, butoxy {polyethylene glycol (poly) propylene glycol (Poly) butylene glycol} mono (meth) acrylate, pentoxypolyethylene glycol mono (meth) acrylate, pentoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, pentoxy {polyethylene glycol (poly) butylene glycol} mono ( Meth) acrylate, pentoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol } Mono (meth) acrylate, hexoxypolyethylene glycol mono (meth) acrylate, hexoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, hexoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, hexoxy {Polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate,

Heptoxy polyethylene glycol mono (meth) acrylate, heptoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, heptoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, heptoxy {polyethylene glycol (poly) propylene Glycol (poly) butylene glycol} mono (meth) acrylate, octoxypolyethylene glycol mono (meth) acrylate, octoxy {polyethyleneglycol (poly) propyleneglycol} mono (meth) acrylate, octoxy {polyethyleneglycol (poly) butyleneglycol} mono (Meth) acrylate, octoxy {polyethylene glycol (poly) propylene glycol (poly) butylene Recall} mono (meth) acrylate, nonanoxy polyethylene glycol mono (meth) acrylate, nonanoxy {polyethylene glycol (poly) propylene glycol} mono (meth) acrylate, nonanoxy {polyethylene glycol (poly) butylene glycol} mono (meth) acrylate, Nonanoxy {polyethylene glycol (poly) propylene glycol (poly) butylene glycol} mono (meth) acrylate.

The vinyl monomer component used to obtain the polymer (ii) also includes the unsaturated carboxylic acid monomer (a) and the unsaturated polyalkylene glycol monomer (b) described above. Other copolymerizable monomers (hereinafter also referred to as “monomer (c)”) may be included.
In this case, the polymer (ii) further includes a structural unit derived from the monomer (c), and the structural unit derived from the monomer (c) is a monomer by polymerization reaction. It corresponds to a structure (a structure in which a double bond (C = C) is converted to a single bond (-C-C-)) having a polymerizable double bond in (c).
When using the said monomer (c), it is suitable to set it as 30 mass% or less with respect to 100 mass% of all the vinyl-type monomer components. More preferably, it is 25 mass% or less, More preferably, it is 20 mass% or less.

Specific examples of the monomer (c) include the following compounds, and one or more of these can be used.
Half esters and diesters of unsaturated dicarboxylic acid monomers such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid and the like and alcohols having 23 to 30 carbon atoms; Half amides and diamides of an alkyl group and an amine having 23 to 30 carbon atoms; an alkyl (poly) alkylene glycol obtained by adding 1 to 500 moles of an alkylene oxide having 2 to 18 carbon atoms to the alcohol or amine and the above unsaturated Half esters and diesters with dicarboxylic acid monomers; half of the above unsaturated dicarboxylic acid monomers and glycols having 5 to 18 carbon atoms or polyalkylene glycols having 2 to 500 addition moles of these glycols Esters, diesters; maleamic acid and glycols having 5 to 18 carbon atoms, or Half amides of polyalkylene glycols of addition mole number 2 to 500 of glycol;

(Poly) alkylene glycols such as triethylene glycol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, (poly) ethylene glycol (poly) propylene glycol di (meth) acrylate, etc. Di (meth) acrylates; polyfunctional (meth) acrylates such as hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate; triethylene glycol dimaleate, polyethylene glycol (Poly) alkylene glycol dimaleates such as dimaleate; vinyl sulfonate, (meth) allyl sulfonate, 2- (meth) acryloxyethyl sulfonate, 3- (meth) acrylate Xylpropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropyl sulfonate, 3- (meth) acryloxy-2-hydroxypropylsulfophenyl ether, 3- (meth) acryloxy-2-hydroxypropyloxysulfobenzoate, 4- ( Unsaturated sulfonic acids such as (meth) acryloxybutyl sulfonate, (meth) acrylamide methyl sulfonic acid, (meth) acrylamide ethyl sulfonic acid, 2-methylpropane sulfonic acid (meth) acrylamide, styrene sulfonic acid, and monovalents thereof Metal salts, divalent metal salts, ammonium salts and organic amine salts;

Amides of unsaturated monocarboxylic acids and amines having 1 to 30 carbon atoms such as methyl (meth) acrylamide; vinyl aromatics such as styrene, α-methylstyrene, vinyltoluene, p-methylstyrene; Alkanediol mono (meth) acrylates such as 4-butanediol mono (meth) acrylate, 1,5-pentanediol mono (meth) acrylate, 1,6-hexanediol mono (meth) acrylate; butadiene, isoprene, 2- Dienes such as methyl-1,3-butadiene and 2-chloro-1,3-butadiene; (meth) acrylamide, (meth) acrylalkylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) Unsaturated amides such as acrylamide; (meth) acrylonitrile, α-chloroa Unsaturated cyanides such as acrylonitrile; unsaturated esters such as vinyl acetate and vinyl propionate.

A more preferred form of the multi-branched polyalkylene glycol polymer (i) is the following general formula (3);

(In the formula, X represents a residue of a compound having 3 or more active hydrogens. AO is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. Y ¹ represents an organic residue. Z is a polymer containing a structural unit derived from a vinyl monomer component, n is the same or different and represents the average number of moles of oxyalkylene group added, and is a number from 5 to 1000. , An integer of 1 to 50.).

In the general formula (3), a residue of a compound having 3 or more active hydrogens represented by X, an oxyalkylene group having 2 to 18 carbon atoms represented by AO, an organic residue represented by Y ¹ , The average number of moles of the polymer represented by Z and the oxyalkylene group represented by n is as described above. M represents the number of polyalkylene glycol chains bonded to the polymer (ii) through an organic residue to which a compound having three or more active hydrogens represented by X is bonded. Just as you did.

The multi-branched polyalkylene glycol polymer (i) may also have a polyalkylene glycol chain that is not bonded to the polymer (ii).
The terminal of such a polyalkylene glycol chain (the terminal opposite to the residue of the compound having 3 or more active hydrogens) is, for example, a hydrogen atom, a monovalent metal atom, a divalent metal atom, an ammonium group, or an organic amine. Having a structure bonded to any one of a group, a hydrocarbon group having 1 to 30 carbon atoms, an oxo hydrocarbon group, an amide hydrocarbon group, a carboxyl hydrocarbon group, a sulfonyl (hydrocarbon) group having 0 to 30 carbon atoms, and the like. In the case where two or more polyalkylene glycol chains are present in one molecule, the terminal structures thereof may be the same or different. Among such terminal structures, from the viewpoint of versatility, a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, more preferably a structure bonded to a hydrogen atom or a carbon hydrogen group having 1 to 10 carbon atoms, Among the hydrocarbon groups having 1 to 10 carbon atoms, an alkyl group and an alkylene group are preferable.
That is, for example, when the multi-branched polyalkylene glycol polymer (i) is a polymer represented by the general formula (3), the polymer is represented by the following general formula (4);

(In the formula, X, AO, Y ¹ , n and m are the same as those in the general formula (3), and n ′ is the same or different and represents the average number of added moles of the oxyalkylene group; The preferred form is the same form as n above, and n and n ′ may be the same or different, and Q is a hydrogen atom or a carbon number of 1 to Represents an alkyl group or an alkylene group of 10. p is an integer of 0 or more, and the maximum number is determined depending on the number of active hydrogens and the number of m of compounds having 3 or more active hydrogens represented by X It may be a compound represented by:
The above p is a number determined by the number of active hydrogens and the number of m of the compound having 3 or more active hydrogens represented by X, and is determined by the polymer (ii) via an organic residue. In order to sufficiently exert the effect due to the bonded polyalkylene glycol chain, p is [(active hydrogen so that the number of the polyalkylene glycol chain bonded to the compound having 3 or more active hydrogens is 3 or more. The total active hydrogen number of the compound having 3 or more) is preferably 3 or less.

The multi-branched polyalkylene glycol polymer (i) of the present invention has a weight average molecular weight (Mw) of 300,000 in consideration of its handleability and retention of cement composition when used for cement admixture. It is preferable that: More preferably, it is 200,000 or less, More preferably, it is 150,000 or less, Most preferably, it is 100,000 or less. Further, when used for cement admixture, it is preferable that Mw is 10,000 or more from the viewpoint that performance is better when adsorbed to cement particles to some extent and Mw is larger so that the adsorptive power becomes larger. More preferably, it is 15000 or more, More preferably, it is 18000 or more, Most preferably, it is 20,000 or more.
In addition, the weight average molecular weight of a polymer can be calculated | required by the gel permeation chromatography (GPC) analysis method mentioned later.

<Method for producing multi-branched polyalkylene glycol-based polymer>
The present invention is also a method for producing the multi-branched polyalkylene glycol polymer (i), wherein the production method comprises the following general formula (5);

(In the formula, X represents a residue of a compound having 3 or more active hydrogens. AO is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. Y ¹ represents an organic residue. N is the same or different and represents the average number of added moles of the oxyalkylene group, and is a number of 5 to 1000. m is an integer of 1 to 50.) Is a method for producing a multi-branched polyalkylene glycol polymer including a step of polymerizing a vinyl monomer component.
A polymer containing a polyalkylene glycol chain and having a multi-branched structure, wherein a vinyl monomer component is polymerized in the presence of the polyalkylene glycol chain-containing compound represented by the general formula (5). The resulting multi-branched polyalkylene glycol-based polymer is also one aspect of the present invention.

In the production method of the multi-branched polyalkylene glycol polymer (i), the polyalkylene glycol chain-containing compound may be any compound having the structure represented by the general formula (5).
In addition, a residue of a compound having 3 or more active hydrogens represented by X, an oxyalkylene group having 2 to 18 carbon atoms represented by AO, an organic residue represented by Y ¹ , and n The average added mole number of the oxyalkylene group is as described above. M represents the number of polyalkylene glycol chains bonded to the polymer (ii) through an organic residue to which a compound having three or more active hydrogens represented by X is bonded. Just as you did.

In the general formula (5), the organic residue represented by Y ¹ is preferably a group containing a sulfur atom as described above. In this case, in this case, the sulfur atom and the general formula (5) A form in which a hydrogen atom present at the terminal is bonded is preferable. That is, the polyalkylene glycol chain-containing compound represented by the general formula (5) is preferably a compound having a mercapto group (thiol group, SH group) (hereinafter, such a compound is referred to as “polyalkylene”). Also referred to as “glycol chain-containing thiol compound”). As a result, it is possible to carry out the polymerization by utilizing the unique reactivity of the mercapto group, and it is possible to produce the polymer (i) of the present invention more efficiently, simply and at low cost. .

In the above production method, when the polyalkylene glycol chain-containing thiol compound is used, a radical generated from the mercapto group by heat, light, radiation, or the like or a radical generated by a polymerization initiator used separately as necessary , Chain transfer to the mercapto group, or when the mercapto groups are bonded to each other to form a disulfide bond, the disulfide bond is cleaved, and the monomers are successively introduced via the sulfur atom (S). The polymer (ii) is added to form a site, so that the polymer (i) of the present invention can be obtained efficiently.
In addition to the polyalkylene glycol chain-containing thiol compound, the polyalkylene glycol chain-containing compound has reactivity with the main chain terminal of the polymer (ii) other than the mercapto group, It is also possible to use one having a group that can be a chain transfer agent or a radical initiator. Examples of such a group include a peroxide group and an azo group. Even with such a compound, the polymerization reaction is carried out in the same manner as the polyalkylene glycol chain-containing thiol compound.

The polyalkylene glycol chain-containing thiol compound is obtained by a production method including a step of dehydrating and condensing a compound obtained by adding alkylene oxide to a compound having 3 or more active hydrogens and a thiol compound having a carboxyl group. It is preferable that
In such a production method, the compound having three or more active hydrogens is preferably a polyhydric alcohol, a polyvalent amine, a polyvalent imine, a polyvalent amide compound or the like, as described above. Polyalkyleneimines and polyhydric alcohols are preferred. These are as described above.
The alkylene oxide is also as described above.
The reaction molar ratio between the compound having 3 or more active hydrogens and the alkylene oxide is preferably set as appropriate so that the average number of repetitions of the alkylene oxide in the polyalkylene glycol chain is within the preferable range.

As a method for adding alkylene oxide to a compound having 3 or more active hydrogens, polymerization can be carried out by an ordinary method, and a method using an acid catalyst or an alkali catalyst is preferable. As the acid catalyst, Lewis acid catalysts such as boron trifluoride, metal and metalloid halogen compounds; mineral acids such as hydrogen chloride, hydrogen bromide and sulfuric acid; paratoluenesulfonic acid and the like are suitable, and alkali catalysts Is preferably potassium hydroxide, sodium hydroxide or sodium hydride.

The reaction time in the addition reaction step may be appropriately set according to the type and amount of the catalyst used, the number of moles of the alkylene oxide added to the compound having 3 or more active hydrogens, the solution concentration, and the like.
A commercially available compound can also be used as a compound obtained by adding alkylene oxide to a compound having three or more active hydrogens (hereinafter also simply referred to as “addition product”).

In the above production method, a compound obtained by adding alkylene oxide to a compound having three or more active hydrogens obtained in this way, and a thiol compound having a carboxyl group (hereinafter also simply referred to as “thiol compound”). Is dehydrated and condensed.
In the dehydration condensation step, the thiol compound having a carboxyl group may be a mercaptocarboxylic acid group-containing compound having a carboxyl group (carboxylic acid group) and a mercapto group in one molecule.
Examples of such a mercaptocarboxylic acid group-containing compound include thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, mercaptoisobutyric acid, thiomalic acid, mercaptostearic acid, mercaptoacetic acid, mercaptobutyric acid, mercaptooctanoic acid. , Mercaptobenzoic acid, mercaptonicotinic acid, cysteine, N-acetylcysteine, mercaptothiazole acetic acid and the like. Among these, thioglycolic acid, 3-mercaptopropionic acid, thiomalic acid, and mercaptoisobutyric acid are preferable.

In the dehydration condensation step of the adduct and the thiol compound, it is preferable that a dehydration condensation reaction is performed between the hydroxyl group of the adduct and the carboxyl group of the thiol compound. It can be carried out using an ordinary method of ester reaction in a normal liquid phase. Further, the pressure may be reduced or an entrainer such as xylene may be used.
In addition, from the property of the mercapto group which the said thiol compound has, it is suitable to perform the said dehydration condensation process under an acid catalyst. The acid catalyst is as described above.
Thus, the dehydration condensation step of the adduct and the thiol compound is preferably an esterification reaction step using an acid catalyst.

What is necessary is just to set suitably as mixing ratio of the said adduct and a thiol compound according to the purity, cost, reaction rate, synthesis method, etc. of a desired polyalkylene glycol chain containing thiol compound. For example, when it is desired to obtain a highly pure polyalkylene glycol chain-containing thiol compound in a short time, the thiol compound has a large excess of carboxyl groups in molar ratio with respect to the amount of hydroxyl groups provided for the reaction of the adduct. It is preferable to do. Specifically, from the viewpoint of reaction rate, the molar ratio is preferably 2 times or more, more preferably 3 times or more, and from the viewpoint of production cost, it is preferably 10 times or less, More preferably, it is 5 times or less. In addition, although the crude product after reaction may be used as it is, it may refine | purify as needed and an unreacted substance may be removed.

As the mixing ratio, when it is desired to reduce the amount of the crude product after the reaction, the carboxyl group of the thiol compound is less than twice the molar ratio with respect to the amount of hydroxyl group provided for the reaction of the adduct. It is preferable to do. Specifically, from the viewpoint of yield, the molar ratio is preferably 0.3 times or more, more preferably 0.5 times or more, still more preferably 0.7 times or more, particularly preferably 0.8. In view of the remaining amount of unreacted material, it is preferably 1.8 times or less, more preferably 1.6 times or less, still more preferably 1.4 times or less, particularly preferably 1 Less than 3 times. Although the crude product after the reaction may be purified as necessary, in this method, since there are few unreacted thiol compounds, the operation of removing this can often be omitted, and the production process is further simplified. be able to.

The reaction time of the dehydration condensation process may be appropriately set according to the type and amount of the acid catalyst used, the mixing ratio of the adduct and the thiol compound, the solution concentration, and the like.

The above production method may also include a step of adjusting the pH of the reaction solution after the dehydration condensation step, whereby the resulting ester can be prevented from being hydrolyzed by the desolvation step. The pH can be adjusted by introducing an alkali such as an aqueous sodium hydroxide solution into the reaction solution obtained by the dehydration condensation step. In order to suppress the hydrolysis reaction, the pH of the reaction solution is preferably 3 or more, more preferably 4 or more, and preferably 7 or less, more preferably 6 or less. More preferably, it is 5.5 or less.

The reaction crude product obtained by the dehydration condensation step is solidified by cooling the reaction solution after the dehydration condensation step (that is, the pH-adjusted reaction solution) or the pH-adjusted reaction solution to room temperature. Is preferred. Thereby, the reaction crude product can be easily obtained from the reaction solution. The solidified product of the obtained reaction crude product may be purified. In this case, after solidifying the reaction crude product is dried and ground, impurities such as unreacted raw material compounds dissolve. The solidified product may be washed using a solvent that does not dissolve the thiol compound, such as diethyl ether.
In view of the increase in manufacturing cost due to the increase in the number of work steps and the environmental load due to the use of the solvent, it is preferable to avoid the cleaning work using the solvent. In this case, the mixing ratio of the adduct, which is a raw material compound, and the thiol compound is 2 in terms of the molar ratio of the carboxyl group of the thiol compound to the amount of hydroxyl group provided for the reaction of the adduct as described above. It is preferable to make it not more than twice.

By the way, the present inventors dried the solidified product of the reaction crude product obtained by the above-described production method, or washed the dried solidified product with diethyl ether or the like to obtain a polymer from the reaction crude product. When trying to obtain an alkylene glycol chain-containing thiol compound, it has been found that a multimerized product is generated by self-multiplication, and the content of the multimerized product may exceed 30% by mass in 100% by mass of the total product. I found it. As a result of further investigation, although the reaction route is unknown, it has been found that the cause of this increase is that the solidified product of the reaction crude product is dried, and if it is in a dry state, whether it is in a vacuum state or not. Regardless of whether or not the dehydration reaction or neutralization reaction is performed, the inventors have found that the quantity increases.

Here, for example, when the viscosity of the polyalkylene glycol chain-containing thiol compound or a solution thereof is required to be low, it is desired that the amount of multimerization is small. In this case, the solidified product of the reaction crude product is dried. It is suitable to handle so as not to. Thereby, the production of multimers is effectively suppressed, and the content of multimers in the polyalkylene glycol chain-containing thiol compound is kept within the range of 1 to 30% by mass with respect to 100% by mass of the compound. Is possible.

Conversely, the amount of the multimerized product can be significantly increased by simply drying the crude reaction product for a certain period of time. The structure of the multimer is presumed to have a polydisulfide structure in which two or more thiol compounds are bonded by disulfation of a mercapto group and have a polyalkylene glycol chain-containing thiol compound residue, but the disulfide bond is a mercapto bond. Since the radical can be easily generated by various methods like the group, this multimer can be used as a chain transfer agent. In addition, the molecular weight of the multimer is reduced due to generation of radicals, and finally decomposed to the structure of the polyalkylene glycol chain-containing thiol compound residue. Therefore, if the polymerized product is used as a chain transfer agent for various radical polymerizations, the polymerized product before reaction has a high viscosity because of its high molecular weight, and the polyalkylene glycol chain-containing thiol compound residue after the reaction has a reduced molecular weight. Becomes smaller. For this reason, the polymerization reaction can be advanced while adjusting the viscosity in the system during the reaction, and application different from the polyalkylene glycol chain-containing thiol compound is possible.
Thus, the form in which the polyalkylene glycol chain-containing thiol compound contains a multimerized product as a by-product is also a preferred form of the present invention.

The multimer can also be synthesized from the polyalkylene glycol chain-containing thiol compound by various methods. For example, the mercapto group of the polyalkylene glycol chain-containing thiol compound is radicalized using heat, light, radiation, a radical generator, etc., disulfidized via sulfur radicals, treated with an oxidizing agent, It is possible to obtain a multimer by treating and disulfiding via a sulfur anion.

Here, an example of a multimerized product of the above polyalkylene glycol chain-containing thiol compound is shown by taking sorbitol as an example of a compound having three or more active hydrogens.
In the following formula, the polyalkylene glycol chain-containing thiol compound is the above-described formula (b) (the compound having 3 or more active hydrogens is sorbitol, and all the active hydrogens in sorbitol have a polyalkylene glycol chain and a carbonyl group. The form in which two mercapto groups generate disulfide bonds to form a dimer in the case where the mercapto group is bonded via a group having the same).

In the above production method, it is preferable to include a step of adding an antioxidant when it is necessary to suppress the amount of the polymerized product from the viewpoint of viscosity or the like. This is because generation of thermal radicals from the mercapto group of the thiol compound due to the reaction between the adduct and the thiol compound under heating is considered as one of the factors for the increase in the number of radicals. By adding an antioxidant having a function, it is possible to effectively suppress the increase in quantity due to the generation of thermal radicals from the mercapto group.

The addition of the antioxidant may be performed in any production process, for example, may be performed in any stage such as a dehydration condensation process, a desolvation process, a purification process, or the like. May be made.
Although it does not specifically limit as said antioxidant, What is necessary is just to use what is used normally, For example, phenothiazine and its derivative; Hydroquinone, catechol, resorcinol, methoquinone, butylhydroquinone, butylcatechol, naphthohydroquinone, dibutylhydroxytoluene Phenol compounds such as butylhydroxyanisole, tocopherol, tocotrienol and catechin; nitro compounds such as tri-p-nitrophenylmethyl, diphenylpicrylhydrozine and picric acid; nitroso compounds such as nitrosobenzene and cuperone; diphenylamine and di-p Amine compounds such as fluorophenylamine and N- (3-N-oxyanilino-1,3-dimethylbutylidene) aniline oxide; TEMPO radical (2,2,6, -Tetramethyl-1-piperidinyloxyl), stable radicals such as diphenylpicrylhydrazyl, galvinoxyl, and ferdazyl; alcorbic acid, erythorbic acid and salts or esters thereof; dithiobenzoyl disulfide; copper (II) chloride, and the like. It may be used alone or in combination of two or more. Among these, phenothiazine and derivatives thereof, phenolic compounds, ascorbic acid, erythorbic acid and esters thereof are preferable, and phenothiazine, hydroquinone and methoquinone are more preferable. These antioxidants are useful in that they can exhibit a polymerization inhibiting ability very effectively both in the dehydration condensation process and in the solvent distillation process.

The amount of the antioxidant added is not particularly limited as long as it can effectively prevent the polyalkylene glycol chain-containing thiol compound from being increased in number. For example, the mass of the polyalkylene glycol chain-containing thiol compound (solid Min), the mass of the antioxidant is preferably 10 ppm or more, and preferably 5000 ppm or less. By setting within this range, the effect of the antioxidant can be more fully exhibited while sufficiently maintaining the characteristics of the thiol compound, but if it exceeds 5000 ppm, the performance of the thiol compound is more enhanced. There is a risk that it may not be fully exhibited or colored. More preferably, it is 20 ppm or more, More preferably, it is 50 ppm or more, Most preferably, it is 100 ppm or more. More preferably, it is 2000 ppm or less, More preferably, it is 1000 ppm or less, Especially preferably, it is 500 ppm or less.

As described above, as a method for obtaining a solidified product of the reaction crude product from the reaction solution after the dehydration-condensation step, a method of heating the reaction solution and distilling off the solvent can be adopted. The content of the multimerized product in the polyalkylene glycol chain-containing thiol compound can be kept within the range of 30% by mass or less in 100% by mass of the compound.

Since the solidified product of the polyalkylene glycol chain-containing thiol compound obtained as described above tends to increase in quantity when dried as described above, it is preferably stored in a solution state. More preferably, it is stored in an aqueous solution state. Further, the pH of the solution is preferably set to 4 or more, more preferably 5 or more, still more preferably 5.5 or more, and particularly preferably 6 or more. Moreover, it is suitable to set to pH 7 or less.

In the above production method, as described above, since the polyalkylene glycol chain-containing thiol compound to be obtained is easily quantified, it may include a step of removing the multimer from the polyalkylene glycol chain-containing thiol compound. Examples of the removing step include molecular weight fractionation methods such as dialysis, ultrafiltration, GPC (gel permeation chromatography) fractionation, and the like. In addition, since the addition of such a removal step of the multimerized product may lead to an increase in production cost, the polyalkylene glycol chain-containing thiol compound containing the multimerized product is used as it is, for example, for the preparation of a polymer described later. It may be used.

In the present invention, the polymerization reaction of the vinyl monomer component is carried out in the presence of a polyalkylene glycol chain-containing compound represented by the polyalkylene glycol chain-containing thiol compound thus obtained.
For example, when the polymerization reaction is performed in the presence of the polyalkylene glycol chain-containing thiol compound, as described above, monomers are successively added via the terminal sulfur atom (S) to form the polymer ( ii) is formed, and thus the polymer (i) of the present invention is produced as a main component. The structure of the polymer (ii) is repeated two or more times, or the monomer (a ), A polymer having a structural unit derived from one or more monomers among the monomer (b) and the monomer (c) may be produced as a secondary.

The amount of the polyalkylene glycol chain-containing compound (preferably polyalkylene glycol chain-containing thiol compound) used in the polymerization reaction is 1 to 80 parts by weight with respect to 100 parts by weight of the vinyl monomer component. Is preferred. If the amount is 1 part by weight or less, the effect due to the polyalkylene glycol chain-containing compound may not be sufficiently exhibited. If the amount exceeds 80 parts by weight, the performance derived from the vinyl monomer may not be sufficiently exhibited. is there. The lower limit of the amount used is more preferably 2 parts by weight, still more preferably 4 parts by weight, and the upper limit is more preferably 50 parts by weight, still more preferably 30 parts by weight. is there.

The polymerization reaction can be performed by a method such as solution polymerization or bulk polymerization using a radical polymerization initiator as necessary. The solution polymerization can be performed batchwise, continuously, or a combination thereof. Examples of the solvent used in this case include water; alcohols such as methyl alcohol, ethyl alcohol, and isopropyl alcohol; benzene, toluene, Aromatic or aliphatic hydrocarbons such as xylene, cyclohexane and n-hexane; ester compounds such as ethyl acetate; ketone compounds such as acetone and methyl ethyl ketone; cyclic ether compounds such as tetrahydrofuran and dioxane. Among them, for example, when used in an application that is often used as an aqueous solution such as a cement admixture, polymerization is preferably performed by an aqueous solution polymerization method.

Among the solution polymerizations described above, in aqueous solution polymerization, it is preferable to use a water-soluble radical polymerization initiator because it is not necessary to remove insoluble components after polymerization. For example, persulfates such as ammonium persulfate, sodium persulfate, and potassium persulfate; hydrogen peroxide; azoamidine compounds such as 2,2′-azobis-2-methylpropionamidine hydrochloride, 2,2′-azobis-2- Cyclic azoamidine compounds such as (2-imidazolin-2-yl) propane hydrochloride, azonitrile compounds such as 2-carbamoylazoisobutyronitrile, 2,4′-azobis {2-methyl-N- [2- (1- Water-soluble azo initiators such as azoamide compounds such as (hydroxybutyl)] propionamide}, macroazo compounds such as esters of 4,4′-azobis (4-cyanovaleric acid) and (alkoxy) polyethylene glycol, These 1 type (s) or 2 or more types can be used. Among these, a water-soluble azo initiator is preferable as will be described later.

At this time, alkali metal sulfites such as sodium hydrogen sulfite, metabisulphite, sodium hypophosphite, Fe (II) salt such as molle salt, sodium hydroxymethanesulfinate dihydrate, hydroxylamine hydrochloride, thiourea , Accelerators (reducing agents) such as L-ascorbic acid (salt) and erythorbic acid (salt) can be used in combination. For example, a combination of hydrogen peroxide and an organic reducing agent is possible. Examples of the organic reducing agent include L-ascorbic acid (salt), L-ascorbic acid ester, erythorbic acid (salt), erythorbic acid ester, and the like. It can be used suitably. These radical polymerization initiators and accelerators (reducing agents) may be used alone or in combination of two or more.
The amount of the accelerator (reducing agent) used is not particularly limited. For example, when the total amount of the polymerization initiator used in combination is 100 mol, it is preferably 10 mol or more, more preferably 20 mol or more. More preferably, it is 50 mol or more, preferably 1000 mol or less, more preferably 500 mol or less, still more preferably 400 mol or less.

In solution polymerization and bulk polymerization using lower alcohols, aromatic or aliphatic hydrocarbons, esters or ketones as solvents, radical polymerization initiators such as benzoyl peroxide, lauroyl peroxide, sodium peroxide, etc. Peroxides such as t-butyl hydroperoxide and cumene hydroperoxide; azonitrile compounds such as azobisisobutyronitrile, 2,4′-azobis {2-methyl-N- [2- (1- Hydroxybutyl)] propionamide} and other water-soluble azo initiators such as macroazo compounds such as esters of 4,4′-azobis (4-cyanovaleric acid) and (alkoxy) polyethylene glycol Or 2 or more types can be used. Among these, a water-soluble azo initiator is preferable as will be described later. In this case, an accelerator such as an amine compound can be used in combination.
Furthermore, when using a mixed solvent of water and a lower alcohol, it can be appropriately selected from the above-mentioned various radical polymerization initiators or a combination of the above radical polymerization initiator and an accelerator.

In the present invention, considering that a mercapto group contained in the polyalkylene glycol chain-containing thiol compound or a radical is generated by heat, light, radiation, or the like from a disulfide bond in the multimer, a mercapto group is used as a polymerization initiator. It is preferable to use a carbon radical generator that easily generates radicals from disulfide bonds. Among these, azo initiators are suitable, and this makes it possible to efficiently obtain the above-described radially branched multi-branched polymer. More preferably, the above-mentioned water-soluble azo initiator is used.
When a persulfate or hydrogen peroxide is used as a polymerization initiator, the mercapto group of the polyalkylene glycol chain-containing thiol compound is oxidized, and the yield of the resulting polymer may not be sufficient. There is.

The amount of the radical polymerization initiator used may be appropriately set according to the aspect and amount of the polyalkylene glycol chain-containing thiol compound, but the radical polymerization initiator is used for the vinyl monomer component to be polymerized. If the amount is too small, the radical concentration may be too low and the polymerization reaction may be slow. Conversely, if the amount is too large, the radical concentration may be too high, resulting in a vinyl monomer component more than the polymerization reaction caused by a mercapto group or disulfide bond. The polymerization reaction from the above has a priority, and there is a possibility that the yield of the above-mentioned radially branched multi-branched polymer cannot be increased. Therefore, the amount of the radical polymerization initiator used is preferably 0.001 mol or more, more preferably 0.01 mol or more, still more preferably 0.1 mol or more, with respect to 100 mol of the total amount of vinyl monomer components. The amount is particularly preferably 0.2 mol or more, preferably 10 mol or less, more preferably 5 mol or less, still more preferably 2 mol or less, particularly preferably 1 mol or less.

In the polymerization reaction, a normal chain transfer agent may be used in combination. Examples of chain transfer agents that can be used include thiol chain transfer agents such as mercaptoethanol, thioglycerol, thioglycolic acid, 3-mercaptopropionic acid, thiomalic acid, and 2-mercaptoethanesulfonic acid; secondary such as isopropyl alcohol. Alcohol; phosphorous acid, hypophosphorous acid and salts thereof (sodium hypophosphite, potassium hypophosphite, etc.), sulfurous acid, hydrogen sulfite, dithionite, metabisulfite and salts thereof (sodium sulfite, hydrogen sulfite) And hydrophilic chain transfer agents such as lower oxides of sodium, sodium dithionite, sodium metabisulfite, and the like, and salts thereof.

A hydrophobic chain transfer agent can also be used as the chain transfer agent. Examples of the hydrophobic chain transfer agent include 3 carbon atoms such as butanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, and octyl 3-mercaptopropionate. A thiol chain transfer agent having the above hydrocarbon group is preferably used.

The chain transfer agents may be used alone or in combination of two or more, and for example, a hydrophilic chain transfer agent and a hydrophobic chain transfer agent may be used in combination.
The amount of the chain transfer agent used may be appropriately set according to the aspect and amount of the polyalkylene glycol chain-containing thiol compound, but is preferably 0.1 mol with respect to 100 mol of the total amount of vinyl monomer components. More preferably, it is 0.25 mol or more, more preferably 0.5 mol or more, and preferably 20 mol or less, more preferably 15 mol or less, still more preferably 10 mol or less.

In the above polymerization reaction, the polymerization conditions such as the polymerization temperature are appropriately determined depending on the polymerization method used, the solvent, the polymerization initiator, and the chain transfer agent, but the polymerization temperature is preferably 0 ° C. or higher, It is preferable that it is 150 degrees C or less. More preferably, it is 30 degreeC or more, More preferably, it is 50 degreeC or more. More preferably, it is 120 degrees C or less, More preferably, it is 100 degrees C or less.

The method for charging the vinyl monomer component into the reaction vessel is not particularly limited, and a method in which the entire amount is initially charged into the reaction vessel; a method in which the entire amount is divided or continuously charged into the reaction vessel; Any of the methods of initially charging the reaction vessel into the reaction vessel and dividing or continuously charging the remainder into the reaction vessel may be used. The radical polymerization initiator and the chain transfer agent may be charged into the reaction vessel from the beginning, may be dropped into the reaction vessel, or may be combined according to the purpose.

In the above polymerization reaction, in order to obtain a copolymer having a predetermined molecular weight with good reproducibility, it is preferable to allow the polymerization reaction to proceed stably. Therefore, in the solution polymerization, the dissolved oxygen concentration at 25 ° C. of the solvent to be used is set to a range of 5 ppm or less (preferably 0.01 to 4 ppm, more preferably 0.01 to 2 ppm, still more preferably 0.01 to 1 ppm). It is preferable to do. In addition, when nitrogen substitution etc. are performed after adding a vinyl-type monomer component to a solvent, it is appropriate to make the dissolved oxygen concentration of the type | system | group containing a vinyl-type monomer component into the said range.

The dissolved oxygen concentration of the solvent may be adjusted in a polymerization reaction tank, or a dissolved oxygen amount may be used in advance. Examples of the method for driving off oxygen in the solvent include the following methods (1) to (5).
(1) After pressurizing and filling an inert gas such as nitrogen into a sealed container containing a solvent, the partial pressure of oxygen in the solvent is lowered by lowering the pressure in the sealed container. In that case, you may reduce the pressure in a sealed container under nitrogen stream.
(2) The liquid phase portion is vigorously stirred for a long time while the gas phase portion in the container containing the solvent is replaced with an inert gas such as nitrogen.
(3) An inert gas such as nitrogen is bubbled in the solvent in the container for a long time.
(4) The solvent is once boiled and then cooled in an inert gas atmosphere such as nitrogen.
(5) A static mixer (static mixer) is installed in the middle of the pipe, and an inert gas such as nitrogen is mixed in the pipe for transferring the solvent to the polymerization reaction tank.

The multi-branched polyalkylene glycol polymer obtained by the above polymerization reaction is adjusted to a pH range of weak acid or higher (more preferably pH 4 or higher, more preferably pH 5 or higher, particularly preferably pH 6 or higher) in an aqueous solution state. It can be made easy to handle.
On the other hand, when the polymerization reaction is carried out at a pH of 7 or more, the polymerization rate is lowered, and at the same time, the copolymerizability is not sufficient. For example, when used for cement admixture, there is a possibility that the dispersion performance cannot be sufficiently exhibited. is there. Therefore, in the polymerization reaction, it is suitable to carry out the polymerization reaction in a pH range from acidic to neutral (more preferably less than pH 6, more preferably less than pH 5.5, still more preferably less than pH 5). As preferred polymerization initiators whose polymerization system becomes acidic to neutral in this way, for example, persulfates such as ammonium persulfate, sodium persulfate, potassium persulfate, and azoamidine compounds such as azobis-2-methylpropionamidine hydrochloride It is preferable to use a water-soluble azo initiator such as hydrogen peroxide, a combination of hydrogen peroxide and an organic reducing agent, or the like. It is more preferable to use at least an azo initiator as described above.

Therefore, after carrying out the polymerization reaction at a low pH, it is preferable to adjust the pH to a higher pH by adding an alkaline substance or the like. Specifically, a method of adjusting the pH to 6 or more by adding an alkaline substance after performing a polymerization reaction at a pH of less than 6; a method of adjusting to a pH of 5 or more by adding an alkaline substance after performing a polymerization reaction at a pH of less than 5; pH 5 For example, a method of adjusting the pH to 6 or more by adding an alkaline substance after carrying out the polymerization reaction at less than the above may be mentioned.
The pH can be adjusted using, for example, an alkaline substance such as inorganic salt such as hydroxide or carbonate of monovalent metal or divalent metal; ammonia; organic amine; In addition, when pH is lowered, particularly when pH adjustment is required during polymerization, acidic substances such as phosphoric acid, sulfuric acid, nitric acid, alkylphosphoric acid, alkylsulfuric acid, alkylsulfonic acid, (alkyl) benzenesulfonic acid are used. Among these acidic substances, phosphoric acid and sulfuric acid capable of lowering the pH with addition of a small amount are preferable among these acidic substances. In addition, after the reaction is completed, the concentration can be adjusted as necessary.

The reaction product obtained by the above polymerization reaction may contain various polymers as by-products as described above in addition to the multi-branched polyalkylene glycol-based polymer. Although it may be subjected to a step of isolating the coalescence, it may usually be used for various purposes without isolating individual polymers from the viewpoint of work efficiency and production cost.

The multi-branched polyalkylene glycol polymer (i) of the present invention is suitably used for various applications such as adhesives, sealing agents, components for imparting flexibility to various polymers, cement admixtures, detergent builders and the like. Among them, the cement admixture containing the above-mentioned multi-branched polyalkylene glycol polymer is also suitable for use as a cement admixture because it can exhibit extremely high cement dispersion performance as described above. Moreover, it is one of the present inventions.
The cement admixture can be used in addition to a cement composition such as cement paste, mortar, concrete, etc., and such a cement composition containing the cement admixture is also one aspect of the present invention.

As the above-mentioned cement composition, those containing cement, water, fine aggregate, coarse aggregate, and the like are suitable. Various mixed cements (blast furnace cement, silica cement, fly ash cement); white Portland cement; alumina cement; super fast cement (1 clinker fast cement, 2 clinker fast cement, magnesium phosphate cement) ); Grout cement; oil well cement; low exothermic cement (low exothermic blast furnace cement, fly ash mixed low exothermic blast furnace cement, cement containing high belite); ultra high strength cement; cement-based solidified material; ecocement (city waste) Cement produced from one or more of incineration ash and sewage sludge incineration ash G) other such, these blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, and a film obtained by adding a fine powder and gypsum limestone powder.
As the above aggregate, in addition to gravel, crushed stone, granulated slag, recycled aggregate, etc. Refractory aggregate.

Examples of the unit water amount per 1 m ³ of the cement composition, the cement use amount, and the water / cement ratio (mass ratio) include, for example, a unit water amount of 100 to 185 kg / m ³ , a use cement amount of 200 to 800 kg / m ³ , and a water / cement ratio. Cement ratio (mass ratio) is preferably 0.1 to 0.7, and more preferably, unit water amount 120 to 175 kg / m ³ , used cement amount 250 to 800 kg / m ³ , water / cement ratio ( (Mass ratio) = 0.2 to 0.65. Thus, the cement admixture containing the polymer (i) of the present invention can be used in a wide range from poor blending to rich blending, and has a high water reduction rate region, that is, a water / cement ratio (mass ratio). ) = 0.15 to 0.5 (preferably 0.15 to 0.4), and can be used in a region with a low water / cement ratio. Further, high strength concrete with a large amount of unit cement and a small water / cement ratio. This is effective for any poorly blended concrete having a unit cement amount of 300 kg / m ³ or less.

As the cement admixture of the present invention, the fluidity, retention and workability can be exhibited with high performance in a balanced manner even in a high water reduction rate region, and since it has excellent workability, ready-mixed concrete, concrete secondary products ( It can be used effectively for concrete for precast concrete), concrete for centrifugal molding, concrete for vibration compaction, steam-cured concrete, shotcrete, etc. Furthermore, medium-fluidity concrete (slump value is 22-25cm) Mortar and concrete that require high fluidity, such as concrete with high fluidity (concrete with a slump value of 25 cm or more and a slump flow value of 50 to 70 cm), self-filling concrete, self-leveling material, etc. Also effective.

When the cement admixture is used in a cement composition, the blending ratio of the polymer (i), which is an essential component of the present invention, is 0 with respect to 100 mass% of the total mass of cement in terms of solid content. It is preferable to set it to be 0.01 to 10% by mass. If it is less than 0.01% by mass, the performance may not be sufficient. On the other hand, if it exceeds 10% by mass, the effect will substantially reach its peak, which may be disadvantageous in terms of economy. More preferably, it is 0.02-8 mass%, More preferably, it is 0.05-6 mass%.

The cement admixture can also be used in combination with other cement additives. As another cement additive, 1 type (s) or 2 or more types, such as a cement additive (material) as shown below, can be used, for example. Among these, it is particularly preferable to use an oxyalkylene antifoaming agent or an AE agent in combination.
In addition, it is suitable for the addition ratio of a cement additive to be 0.0001-10 weight part with respect to 100 weight part of solid content of the said polymer (i).

(1) Water-soluble polymer substances: polyacrylic acid (sodium), polymethacrylic acid (sodium), polymaleic acid (sodium), unsaturated carboxylic acid polymer such as sodium salt of acrylic acid / maleic acid copolymer; polyethylene Polymers of polyoxyethylene or polyoxypropylene such as glycol and polypropylene glycol or copolymers thereof; Nonionic cellulose ethers such as methylcellulose, ethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose, carboxymethylcellulose, carboxyethylcellulose, hydroxypropylcellulose, etc. Yeast glucan, xanthan gum, β-1,3 glucans (both linear and branched), for example, curdlan, paramylon, pachyman, Polyacrylamide; polyvinyl alcohol; starch; starch phosphate ester; sodium alginate; gelatin; copolymer of acrylic acid having an amino group in the molecule and its four Grade compounds and the like.

(2) Polymer emulsion.
(3) Retardant: Gluconic acid, malic acid or citric acid, and oxycarboxylic acids such as inorganic salts or organic salts such as sodium, potassium, calcium, magnesium, ammonium, triethanolamine, and salts thereof; glucose; , Fructose, galactose, saccharose; sugar alcohols such as sorbitol; magnesium silicate; phosphoric acid and its salts or borate esters; aminocarboxylic acid and its salts; alkali-soluble protein; humic acid; tannic acid; Polyhydric alcohols such as aminotri (methylenephosphonic acid), 1-hydroxyethylidene-1,1-diphosphonic acid, ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylenephosphonic acid) and alkali metal salts thereof, al Phosphonic acids and derivatives thereof such as Li earth metal salts.

(4) Early strengthening agent / accelerator: soluble calcium salt such as calcium chloride, calcium nitrite, calcium nitrate, calcium bromide, calcium iodide; alkanolamine; alumina cement; calcium aluminate silicate.
(5) Mineral oil-based antifoaming agent: cocoon oil, liquid paraffin, etc.
(6) Fat and oil-based antifoaming agents: animal and vegetable oils, sesame oil, castor oil, and alkylene oxide adducts thereof.
(7) Fatty acid-based antifoaming agent: oleic acid, stearic acid, and these alkylene oxide adducts.
(8) Fatty acid ester antifoaming agent: glycerin monoricinoleate, alkenyl succinic acid derivative, sorbitol monolaurate, sorbitol trioleate, natural wax and the like.

(9) Oxyalkylene antifoaming agents: polyoxyalkylenes such as (poly) oxyethylene (poly) oxypropylene adducts; diethylene glycol heptyl ether, polyoxyethylene oleyl ether, polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene (Poly) oxyalkyl ethers such as 2-ethylhexyl ether and higher alcohols having 12 to 14 carbon atoms such as oxyethyleneoxypropylene adducts; (poly) oxy such as polyoxypropylene phenyl ether and polyoxyethylene nonylphenyl ether Alkylene (alkyl) aryl ethers; 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 2,5-dimethyl-3-hexyne-2,5-diol, 3-methyl-1 -Bu Acetylene ethers obtained by addition polymerization of alkylene oxide to acetylene alcohol such as n-3-ol; (poly) oxyalkylene fatty acid esters such as diethylene glycol oleate, diethylene glycol laurate, ethylene glycol distearate; polyoxyethylene (Poly) oxyalkylene sorbitan fatty acid esters such as sorbitan monolaurate and polyoxyethylene sorbitan trioleate; (poly) oxyalkylene alkyls such as sodium polyoxypropylene methyl ether sulfate and sodium polyoxyethylene dodecylphenol ether sulfate ( Aryl) ether sulfate esters; (poly) oxyethylene stearyl phosphates, etc. Polyoxyalkylene alkyl phosphoric acid esters; polyoxyethylene such as polyoxyethylene lauryl amine (poly) oxyalkylene alkyl amines; polyoxyalkylene amide.

(10) Alcohol-based antifoaming agent: octyl alcohol, hexadecyl alcohol, acetylene alcohol, glycols and the like.
(11) Amide antifoaming agent: acrylate polyamine and the like.
(12) Phosphate ester antifoaming agent: tributyl phosphate, sodium octyl phosphate, etc.
(13) Metal soap type antifoaming agent: aluminum stearate, calcium oleate, etc.
(14) Silicone antifoaming agent: dimethyl silicone oil, silicone paste, silicone emulsion, organically modified polysiloxane (polyorganosiloxane such as dimethylpolysiloxane), fluorosilicone oil and the like.
(15) AE agent: resin soap, saturated or unsaturated fatty acid, sodium hydroxystearate, lauryl sulfate, ABS (alkyl benzene sulfonic acid), LAS (linear alkyl benzene sulfonic acid), alkane sulfonate, polyoxyethylene alkyl (phenyl) ether , Polyoxyethylene alkyl (phenyl) ether sulfate or a salt thereof, polyoxyethylene alkyl (phenyl) ether phosphate or a salt thereof, protein material, alkenylsulfosuccinic acid, α-olefin sulfonate, and the like.

(16) Other surfactants: aliphatic monohydric alcohols having 6 to 30 carbon atoms in the molecule such as octadecyl alcohol and stearyl alcohol, and those having 6 to 30 carbon atoms in the molecule such as abiethyl alcohol Intramolecular monohydric alcohols such as alicyclic monohydric alcohol, dodecyl mercaptan, etc. Intramolecular such as monohydric mercaptans having 6-30 carbon atoms in the molecule, such as nonylphenol, alkylphenols having 6-30 carbon atoms in the molecule, dodecylamine, etc. 10 mol or more of an alkylene oxide such as ethylene oxide and propylene oxide was added to a carboxylic acid having 6 to 30 carbon atoms in the molecule such as amine having 6 to 30 carbon atoms, lauric acid and stearic acid. Polyalkylene oxide derivatives; having an alkyl group or alkoxyl group as a substituent Alkyldiphenyl ether sulfonates in which two phenyl groups having a sulfone group are ether-bonded; various anionic surfactants; various cationic surfactants such as alkylamine acetate and alkyltrimethylammonium chloride; various nonions Surfactants; various amphoteric surfactants.
(17) Waterproofing agent: fatty acid (salt), fatty acid ester, oil and fat, silicon, paraffin, asphalt, wax and the like.
(18) Rust preventive: nitrite, phosphate, zinc oxide and the like.
(19) Crack reducing agent: polyoxyalkyl ethers; alkanediols such as 2-methyl-2,4-pentanediol.
(20) Expansion material: Ettlingite, coal, etc.

Other cement additives (materials) include, for example, cement wetting agents, thickeners, separation reducing agents, flocculants, drying shrinkage reducing agents, strength enhancing agents, self-leveling agents, rust preventives, colorants, antifungal agents , Blast furnace slag, fly ash, cinder ash, clinker ash, husk ash, silica fume, silica powder, gypsum and the like.

Since the polyalkylene glycol chain-containing thiol polymer of the present invention has the above-described configuration and can exhibit extremely excellent dispersion performance, it is useful for various uses, particularly for cement admixtures. Moreover, according to the method for producing a polyalkylene glycol chain-containing thiol polymer of the present invention, such a polyalkylene glycol chain-containing thiol polymer can be produced simply and efficiently at low cost, This is a very useful technique.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples. Unless otherwise specified, “%” means “mass%” and “part” means “part by weight”.
First, as an analysis method for polyalkylene glycol chain-containing thiol compounds, polymers thereof and comparative polymers, liquid chromatography (LC) analysis conditions / analysis conditions, and gel permeation chromatography (GPC) analysis conditions / analysis conditions Will be described. A measurement method for obtaining these solid contents will also be described.

<LC analysis method>
Device: Waters Alliance (2695)
Analysis software: Emper professional manufactured by Waters + GPC option column: GL Science Inertsil ODS-2 guard column + column (inner diameter 4.6 mm x 250 mm x 3)
Detector: differential refractometer (RI) detector (Waters 2414), multi-wavelength visible ultraviolet (PDA) detector (Waters 2996)
Eluent: A mixture of acetonitrile / 100 mM acetate ion exchange aqueous solution = 40/60 (mass%) adjusted to pH 4.0 by adding 30% NaOH aqueous solution Flow rate: 0.6 mL / min Column temperature: 40 ° C.
Sample solution injection amount: 100 μL (eluent solution having a sample concentration of 1% by mass)

<LC analysis conditions: consumption rate of adduct and average number of introduced SH>
The consumption rate of the adduct as a raw material component was estimated as follows.
According to LC analysis, no mercapto group was introduced (unreacted raw material), polyalkylene glycol chain-containing thiol compound into which one mercapto group was introduced (also referred to as “PAG thiol compound”), ..., mercapto The peaks of the PAG thiol compound into which (m + p) groups have been introduced are separated. These RI (differential refractometer) area ratios (%) were S ₀ , S ₁ ,... S _{m + p,} and the consumption rate of the adducts of the raw material components was estimated by the following equation (1).

Moreover, the average number of SH introduction | transduction in a PAG thiol compound was estimated by the following formula | equation (2).

<GPC analysis method>
The weight average molecular weights of the polyalkylene glycol chain-containing thiol polymer and the comparative polymer were measured under the following measurement conditions.
Device: Waters Alliance (2695)
Analysis software: Waters, Empor professional + GPC option column: Tosoh Co., Ltd., TSK guardcolumns SWXL + TSKgel G4000SWXL + G3000SWXL + G2000SWXL
Detector: differential refractometer (RI) detector (Waters 2414), multi-wavelength visible ultraviolet (PDA) detector (Waters 2996)
Eluent: A solution prepared by dissolving 115.6 g of sodium acetate trihydrate in a mixed solvent of 10999 g of water and 6001 g of acetonitrile, and further adjusting the pH to 6.0 with acetic acid. Standard material for preparing a calibration curve: polyethylene glycol (peak top molecular weight (Mp ) 272500, 219300, 107000, 50000, 24000, 12600, 7100, 4250, 1470)
Calibration curve: Flow rate prepared by cubic equation based on Mp value of polyethylene glycol and elution time: 1 mL / min Column temperature: 40 ° C
Measurement time: 45 minutes Sample solution injection amount: 100 μL (PAG, PAG thiol compound is an eluent solution having a sample concentration of 0.4% by mass, and polymer is a sample concentration of 0.5% by mass)

<GPC analysis condition 1 (analysis of PAG thiol compound (monomer))>
In the RI chromatogram, the portions that were flat and stable in the baseline immediately before and after elution were connected by straight lines, and peaks were detected and analyzed. When a multimer or an impurity was measured partially overlapping the target peak, the molecular weight of the target product was measured by vertically dividing at the most concave portion of the overlapping portion of the peak.
Calculation of monomer content and amount of polymerized product;
From the ratio of the peak area by the RI detector, the calculation was performed as follows.
Monomer pure amount = (PAG thiol compound area) / (multimer peak area + PAG thiol compound area)
Multimerized product amount = (multimerized product peak area) / (multimerized product peak area + PAG thiol compound area)

<GPC analysis condition 2 (analysis of polymer)>
In the obtained RI chromatogram, the portions that were flat and stable in the baseline immediately before and after elution of the polymer were connected with a straight line, and the polymer was detected and analyzed. However, when the peak of the monomer or monomer-derived impurity is measured partially overlapping the polymer peak, the polymer part and the monomer are divided vertically at the most concave part of the overlapping part of the polymer and the polymer peak. The molecular weight and molecular weight distribution of only the polymer part were measured. When the polymer part and other parts could not be completely overlapped and separated, they were calculated together.
Calculation of polymer purity:
From the ratio of the peak area by the RI detector, the calculation was performed as follows.
Polymer pure content = (polymer peak area) / (polymer peak area + monomer or impurity peak area)

<Measurement of solid content (analysis of PAG thiol compound and polymer)>
About 0.5 g of the sample was weighed on an aluminum dish and diluted with about 1 g of water to spread it uniformly. The sample was dried at 130 ° C. for 1 hour in a nitrogen atmosphere, allowed to cool in a desiccator, and then weighed after drying. The solid content (nonvolatile content) concentration was calculated from the difference in mass before and after drying.
As the concentration of the aqueous solution of the PAG thiol compound or polymer, the solid content measured by the above procedure was used unless otherwise specified.

<Synthesis example of adduct (multi-branched alcohol)>
Synthesis Example 1: TMP → TMP-30
Trimethylolpropane (Wako Pure Chemical Industries, 200 g, hereinafter also referred to as “TMP”) and a 30% aqueous sodium hydroxide solution (3.62 g) were charged into a pressure-resistant reaction vessel equipped with a stirrer. The inside of the reaction system was heated to 100 ° C. using an oil bath, and while slowly bubbling nitrogen through the system, the pressure was reduced to 100 mm Torr with a vacuum pump for 2.53 g of water. Furthermore, after reducing the pressure to 100 mmTorr with a vacuum pump for 1 hour, the inside of the reactor was heated to 130 ° C., and nitrogen was introduced to adjust the internal pressure to 0.5 MPa. While maintaining the reactor internal temperature at 130 ± 2 ° C., ethylene oxide (19699.9 g, 30 mol times with respect to TMP) was added. However, the internal pressure of the reactor was not allowed to exceed 0.8 MPa. After completion of the addition of ethylene oxide, the inside of the reactor was kept at 130 ° C. for 1 hour to complete the reaction. From the mass before and after the reaction, the yield was 99.7% and an ethylene oxide 29.9 mol adduct of trimethylolpropane (hereinafter also referred to as “TMP-30”) was obtained.

Synthesis Example 2: TMP-30 → TMP-225
The same procedure as in Synthesis Example 1 except that the raw materials were TMP-30 (300 g), 30% aqueous sodium hydroxide solution (2.97 g), ethylene oxide (1784.7 g, 196 mol times relative to TMP-30) The reaction was carried out. The yield was 99.6%, and a trimethylolpropane ethylene oxide 225 mol adduct (hereinafter also referred to as “TMP-225”) was obtained.

Synthesis Example 3: TMP-30 → TMP-330
Same as Synthesis Example 1 except that TMP-30 (200 g), 30% aqueous sodium hydroxide solution (3.05 g), ethylene oxide (1827.8 g, 301.1 mol times with respect to TMP-30) were used as raw materials. The reaction was performed according to the procedure. The yield was 99.7%, and an ethylene oxide 330 mole adduct of trimethylolpropane (hereinafter also referred to as “TMP-330”) was obtained.

Synthesis Example 4: TMP-225 → TMP-465
Same as Synthesis Example 1, except that TMP-225 (1000 g), 30% aqueous sodium hydroxide solution (1.77 g), ethylene oxide (1059.0 g, 241.5 mol times with respect to TMP-225) were used as raw materials. The reaction was performed according to the procedure. The yield was 99.7%, and an 465 mol ethylene oxide adduct of trimethylolpropane (hereinafter also referred to as “TMP-465”) was obtained.

Synthesis Example 6: SB → SB-30
Sorbitol (Wako Pure Chemical Industries, 250 g, hereinafter also referred to as “SB”) and 30% aqueous sodium hydroxide solution (3.44 g) were charged into a pressure-resistant reaction vessel equipped with a stirrer. The inside of the reaction system was heated to 130 ° C. using an oil bath, and while slowly bubbling nitrogen through the system, the pressure was reduced to 100 mm Torr with a vacuum pump for 1 hour to distill off water. Further, the pressure was reduced to 100 mm Torr with a vacuum pump for 1 hour, and then nitrogen was introduced to adjust the internal pressure to 0.5 MPa. While maintaining the reactor internal temperature at 130 ± 2 ° C., ethylene oxide (1813.6 g, 30 mol times with respect to SB) was added. However, the internal pressure of the reactor was not allowed to exceed 0.8 MPa. After completion of the addition of ethylene oxide, the inside of the reactor was kept at 130 ° C. for 1 hour to complete the reaction. From the weight before and after the reaction, the yield was 99.7%, and 29.9 mol of sorbitol ethylene oxide adduct (hereinafter also referred to as “SB-30”) was obtained.

Synthesis Example 7: SB-30 → SB-120
The same as Synthesis Example 6 except that the raw materials were SB-30 (600 g), 30% aqueous sodium hydroxide solution (2.66 g), and ethylene oxide (1595.4 g, 90.5 mol times relative to SB-30). The reaction was performed according to the procedure. The yield was 99.7%, and an ethylene oxide 120 mol adduct of sorbitol (hereinafter also referred to as “SB-120”) was obtained.

Synthesis Example 8: SB-120 → SB-300
The same procedure as in Synthesis Example 6 except that the raw materials were SB-120 (800 g), 30% aqueous sodium hydroxide solution (1.94 g), and ethylene oxide (1166.5 g, 181 mol times with respect to SB-30). The reaction was carried out. The yield was 99.7%, and an ethylene oxide 300 mol adduct of sorbitol (hereinafter also referred to as “SB-300”) was obtained.

Synthesis Example 9: SB-30 → SB-60
The same as Synthesis Example 6 except that the raw materials were SB-30 (600 g), 30% aqueous sodium hydroxide solution (0.90 g), and ethylene oxide (537.7 g, 30.5 mol times relative to SB-30). The reaction was performed according to the procedure. The yield was 99.7%, and an ethylene oxide 60 mol adduct of sorbitol (hereinafter also referred to as “SB-60”) was obtained.

<Polyalkylene glycol chain-containing thiol compound (PAG thiol compound)>
Production Example 1
(1) Dehydration esterification reaction process In a glass reactor equipped with a Dean-Stark device with a Dimroth condenser, a Teflon (R) stirring blade and a stirring seal, and a temperature sensor with a glass protective tube, Polyalkylene glycol chain-containing triol obtained by adding 225 mol of ethylene oxide to 1 mol of trimethylolpropane (TMP-225, 250.00 g), 3-mercaptopropionic acid (3-MPA, 8.72 g), p-toluenesulfonic acid-water A Japanese product (PTS, 5.17 g), phenothiazine (PTZ, 0.0517 g), and cyclohexane (12.94 g) were charged. After the Dean-Stark apparatus was filled with cyclohexane, the reaction system was heated to reflux while stirring. The temperature of the heating oil bath was 120 ± 5 ° C. The reaction was completed by heating and refluxing for 44.5 hours while adding cyclohexane in the middle so that the temperature in the reaction system became 110 ± 5 ° C.
As a result of LC analysis after completion of the reaction, the consumption rate of TMP-225 was 99.6%, and the average number of SH introduced per molecule of TMP-225 was 2.79.

(2) Desolvation step After completion of the reaction, the mixture was allowed to cool to 60 ° C. with stirring so as not to solidify, and then an aqueous solution in which water (247.88 g) was added to 30% NaOH aqueous solution (3.45 g) was quickly reacted. I put it in the vessel. Subsequently, the temperature was gradually raised to about 100 ° C., and cyclohexane was distilled off. The heating was stopped, nitrogen was bubbled at 30 mL / min for 90 minutes while cooling, and the remaining cyclohexane was removed to obtain an aqueous solution of the target compound (PAG thiol compound (1)).
As a result of LC analysis of the obtained target compound, the consumption rate of TMP-225 was 99.1%, and the average number of SH introduced per molecule of TMP-225 was 2.73. As a result of GPC analysis, the monomer amount was 78.0%, and the remainder was a multimer.

Production Examples 2-6
An aqueous solution of the target compound (PAG thiol compounds (2) to (6)) was obtained in the same manner as in Production Example 1 except that the raw material compounds and reaction conditions were changed as shown in Tables 1 and 2 in Production Example 1. It was.
Table 2 shows the LC analysis results and GPC analysis results after the esterification step and after the desolvation step.

<Polyalkylene glycol chain-containing thiol polymer>
Example 1 (BPT-91)
As a monomer solution, sodium methacrylate (SMAA, 0.92 g), methacrylic acid (MAA, 6.57 g), methoxypolyethylene glycol methacrylate (average number of ethylene oxide additions 25 mol, PGM25E, 51.95 g), Production Example 1 A solution was prepared by adding ion exchange water to the obtained PAG thiol compound (1) (3.06 g) and sodium hydroxide (NaOH, 0.30 g) to make a total of 100 g.
As an initiator solution, 2,2′-azobis (2-methylpropionamidine) dihydrochloride (V-50 manufactured by Wako Pure Chemical Industries, Ltd., V69, 0.069 g) was added with ion-exchanged water to prepare a total solution of 50 g.
Dimroth condenser, Teflon (R) stirrer and stirrer with stir seal, nitrogen inlet tube, and glass reaction vessel equipped with temperature sensor were charged with ion-exchanged water (100 g) and nitrogen was stirred at 250 rpm. The mixture was heated to 80 ° C. while introducing at 200 mL / min.
Subsequently, the monomer solution was dropped into the reaction vessel over 4 hours and the initiator solution over 5 hours. The polymerization reaction was completed by maintaining at 80 ° C. for 1 hour after completion of the dropping. After cooling to room temperature, 30% NaOH aqueous solution was added to adjust pH to 6.0 to obtain an aqueous solution of the target polymer.
As a result of GPC analysis, the polymer was Mw = 113751, Mp = 126140, and Mn = 55041. The pure polymer content was 96.8%.

Examples 2 to 24 (BPT-92 to BPT-115)
An aqueous solution of the target polymer was obtained in the same manner as in Example 1 except that the types and charged amounts of the monomer solution and the initiator solution were changed as shown in Tables 3 and 4.
Table 4 shows the GPC analysis results.

Example 25 (IB-110)
As the monomer solution, a solution of acrylic acid (AA, 9.33 g), the PAG thiol compound (1) (6.09 g) obtained in Production Example 1 and ion-exchanged water (31.05 g) was prepared.
As an initiator solution, 2,2′-azobis (2-methylpropionamidine) dihydrochloride (V-50, Wako Pure Chemical Industries, Ltd., V-50, 0.0962 g) was added with ion exchange water to prepare a total solution of 37.5 g.
Dimroth condenser, Teflon (R) stirrer and stirrer with stir seal, nitrogen inlet tube, glass reactor equipped with temperature sensor, ethylene oxide adduct of 3-methyl-3-buten-1-ol ( An average ethylene oxide addition number of 50 mol, IPN-50, 109.58 g) and ion-exchanged water (56.45 g) were charged, and the mixture was heated to 80 ° C. while stirring at 300 rpm and introducing nitrogen at 200 mL / min.
Subsequently, the monomer solution was dropped into the reaction vessel over 3 hours and the initiator solution over 3.5 hours.
The polymerization reaction was completed by maintaining at 80 ° C. for 1 hour after completion of the dropping. After cooling to room temperature, 30% NaOH aqueous solution was added to adjust pH to 6.0 to obtain an aqueous solution of the target polymer.
As a result of GPC analysis, the polymer was Mw = 53597, Mp = 60508, and Mn = 25696. The pure polymer content was 86.4%.

Examples 26-36 (IB-1111-IB-126)
An aqueous solution of the target polymer was obtained in the same manner as in Example 25 except that the types and amounts of the monomer solution and the initiator solution were changed as shown in Tables 5 and 6 in Example 25. Table 6 shows the GPC analysis results.

In Tables 3 to 6, the composition of the polymer is expressed as a mass ratio in terms of complete neutralization with NaOH (when the carboxylic acid is completely neutralized with NaOH). The total is not 100% because of consideration.

Comparative Example 1 (F-1)
As a monomer solution, sodium methacrylate (SMAA, 0.93 g), methacrylic acid (MAA, 73.29 g), methoxypolyethylene glycol methacrylate (average number of ethylene oxide additions 25 mol, PGM25E, 371.72 g), 3-mercaptopropion A solution of acid (MPA, 4.06 g) and ion-exchanged water (112.5 g) was prepared.
As an initiator solution, a solution of ammonium persulfate (APS, Wako Pure Chemical Industries, 5.13 g) and ion-exchanged water (82.37 g) was prepared.
Dimroth condenser, Teflon (R) stirrer and stirrer with stirring seal, nitrogen inlet tube, glass reaction vessel equipped with temperature sensor, charged with ion-exchanged water (350.00 g), stirred at 200 rpm, The mixture was heated to 80 ° C. while introducing nitrogen at 200 mL / min.
Subsequently, the above monomer solution was dropped into the reaction vessel over 4 hours and the initiator solution over 5 hours, and after completion of the dropping, the reaction was maintained at 80 ° C. for 1 hour to complete the polymerization reaction. After cooling to room temperature, a 30% aqueous NaOH solution was added to adjust the pH to 7.0 to obtain a comparative polymer aqueous solution.
As a result of GPC analysis, the polymer was Mw = 24200, Mp = 18600, and Mn = 1260. The pure polymer content was 95.3%.

Comparative Example 5 (L-2)
Acrylic acid (AA, manufactured by Nippon Shokubai Co., Ltd.) and ion-exchanged water as a monomer solution, and 30% hydrogen peroxide (H ₂ O ₂ , Wako Pure) as a kettle charge initiator solution in the amounts shown in Table 9. L-ascorbic acid (L-AS, manufactured by Wako Pure Chemical Industries, Ltd.), 3-mercaptopropionic acid (MPA), and ion-exchanged water solution were prepared as transfer agent solutions. .
The amount of 3-methyl-3-butene-1 shown in Table 9 was added to a glass reaction vessel equipped with a Dimroth condenser, a stirrer made of Teflon (R), a stirrer with a stirring seal, a nitrogen inlet tube, and a temperature sensor. -All ethylene oxide adduct (average number of ethylene oxide additions 50 mol, IPN-50), acrylic acid (AA, manufactured by Nippon Shokubai) and ion-exchanged water were charged while stirring at 200 rpm and introducing nitrogen at 200 mL / min 58 Warmed to ° C. Next, the whole amount of the kettle charging initiator aqueous solution was charged and heated to 58 ° C. Subsequently, the monomer solution was dropped into the reaction vessel over 3 hours and the transfer agent solution over 3.5 hours, and the polymerization reaction was completed by maintaining at 58 ° C. for 1 hour after the completion of dropping. After cooling to room temperature, a 30% aqueous NaOH solution was added to adjust to pH = 6.0 to obtain an aqueous solution of a comparative polymer. Table 9 shows the amount of each compound used, and Table 10 shows the GPC analysis results of the resulting aqueous solution of the comparative polymer.

In Tables 7 to 10, the composition of the polymer is expressed as a mass ratio in terms of complete neutralization with NaOH (when the carboxylic acid is completely neutralized with NaOH).

<Method for evaluating cement dispersion performance: mortar test>
Examples 37-46, Comparative Examples 8-11
The mortar test was performed in an environment where the temperature was 20 ° C. ± 1 ° C. and the relative humidity was 60% ± 10%.
The mortar formulation was C / S / W = 550/1350/220 (g). However,
C: Ordinary Portland cement (manufactured by Taiheiyo Cement)
S: Standard sand for cement strength test (Cement Association)
W: As an ion exchange aqueous solution W of the polymer of the present invention or a comparative polymer and an antifoaming agent, an addition amount of the polymer aqueous solution shown in Tables 11 and 12 was weighed, and the antifoaming agent MA-404 (Pozoris product manufactured ) In solid form and 10% by mass with respect to the solid content of the polymer, and further ion-exchanged water was added to obtain a predetermined amount, which was sufficiently uniformly dissolved. In Tables 11 and 12, the addition amount of the polymer is represented by mass% of the polymer solid content with respect to the cement mass.
A stainless beater (stirring blade) was attached to a Hobart mortar mixer (model number N-50; manufactured by Hobart), C and W were added, and kneaded at a first speed for 30 seconds. Further, S was added over 30 seconds while kneading at a first speed. After the completion of S addition, the kneading was continued for 30 seconds in duplicate, then the mixer was stopped, the mortar was scraped off for 15 seconds, and then allowed to stand for 75 seconds. The mixture was allowed to stand for 75 seconds and then kneaded at a second speed for 60 seconds to prepare a mortar.

The mortar was transferred from the kneading vessel to a 1 L polyethylene container, stirred 20 times with a spatula, and then immediately packed in a half of a flow cone (described in JIS R5201-1997) placed on a flow table (described in JIS R5201-1997). I struck it with a stick, and stuffed the mortar to the full extent of the flow cone and struck it with a stick with 15 turns. Immediately after that, the flow cone is pulled up vertically, and the diameter of the expanded mortar (the diameter of the longest part (major axis) and the diameter of the part forming 90 degrees with respect to the major axis) is measured at two locations, and the average value is 0 times. The flow value was used. Immediately after measuring the zero stroke flow value, 15 falling motions were given in 15 seconds, and the diameter of the expanded mortar (the diameter of the longest part (major axis) and the diameter of the part forming 90 degrees with respect to the major axis) was 2 The points were measured and the average value was taken as the 15-stroke flow value. Moreover, the amount of mortar air was also measured as needed.
The 0-stroke flow value and the 15-stroke flow value are more excellent in dispersion performance as the numerical value is larger.

<Method of measuring the amount of mortar air>
About 200 mL of mortar was packed in a 500 mL glass graduated cylinder, pushed with a round bar having a diameter of 8 mm, and gently shaken by hand to remove coarse bubbles. Further, about 200 mL of mortar was added and air bubbles were similarly removed. Then, the volume and mass of the mortar were measured, and the amount of air was calculated from the density of each material.

From the results in Table 11, the following was found.
As a result of the mortar test, the polyalkylene glycol chain-containing thiol polymer used in Examples 37 to 41 had a flow value 15 strokes greater than that of the polymer of Comparative Example 8 by 10 mm or more with the same addition amount.
From the result of increasing the amount of addition of the polymer of Comparative Example 8 (Comparative Example 9), it is considered that the amount of addition is about 0.0725% in order to make the 15-stroke flow value 200 mm using Comparative Example 8. The polyalkylene glycol chain-containing thiol polymer has an addition amount of 0.065% and a 15-stroke flow value of 200 mm or more. That is, the polymer obtained the same flow value (0.065 / 0.0725 = 90%) with an addition amount of 10% or more smaller than that of Comparative Example 8 and shows that the cement dispersibility is very high. ing.

From the results in Table 12, the following was found.
As a result of the mortar test, the polyalkylene glycol chain-containing thiol polymer used in Examples 42 to 46 had a flow rate of 15 strokes greater than that of the polymer of Comparative Example 10 by 9 mm or more at the same addition amount.
From the result of increasing the amount of the polymer of Comparative Example 10 (Comparative Example 11), it is considered that the amount of addition is about 0.084% in order to make the 15-stroke flow value to 205 mm using Comparative Example 10. All of the polyalkylene glycol chain-containing thiol polymers have an addition amount of 0.08% and a 15-stroke flow value of 205 mm or more. That is, the polymer has the same flow value (0.08 / 0.084 = 95%) with an addition amount of 5% or more less than that of Comparative Example 10 and shows that the cement dispersibility is very high. ing.

Claims (13)

A polymer containing a polyalkylene glycol chain and having a multi-branched structure,
In the polymer, the polyalkylene glycol chain is bonded to a residue of a compound having 3 or more active hydrogens, and the terminal oxygen atom at the other end of the polyalkylene glycol chain is a vinyl monomer component. A multi-branched polyalkylene glycol polymer having a structure in which a main chain terminal of a polymer containing a derived structural unit is bonded via an organic residue. The multi-branched polyalkylene glycol polymer according to claim 1, wherein the vinyl monomer component essentially contains an unsaturated carboxylic acid monomer. The multi-branched polyalkylene glycol polymer according to claim 1 or 2, wherein the vinyl monomer component essentially contains an unsaturated polyalkylene glycol monomer. The multi-branched polyalkylene glycol polymer according to any one of claims 1 to 3, wherein the organic residue contains a sulfur atom. The polyalkylene glycol chain-containing thiol compound according to claim 4, wherein the organic residue further contains a carbonyl group or an amide group. The polyalkylene glycol chain-containing thiol compound according to any one of claims 1 to 5, wherein the polyalkylene glycol chain has an average number of alkylene oxide repeats of 5 to 1,000. The residue of the compound having 3 or more active hydrogens is at least one polyvalent compound residue selected from the group consisting of a polyvalent amine residue, a polyalkyleneimine residue, and a polyhydric alcohol residue. The multibranched polyalkylene glycol polymer according to any one of claims 1 to 6. The multi-branched polyalkylene glycol polymer is represented by the following general formula (3);

(In the formula, X represents a residue of a compound having 3 or more active hydrogens. AO is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. Y ¹ represents an organic residue. Z is a polymer containing a structural unit derived from a vinyl-based monomer component, n is the same or different and represents the average number of moles of oxyalkylene groups added, and is a number from 5 to 1000. The multi-branched polyalkylene glycol polymer according to any one of claims 1 to 7, which has a structure represented by: A method for producing the multi-branched polyalkylene glycol polymer according to any one of claims 1 to 8,
The production method comprises the following general formula (5):

(In the formula, X represents a residue of a compound having 3 or more active hydrogens. AO is the same or different and represents an oxyalkylene group having 2 to 18 carbon atoms. Y ¹ represents an organic residue. N is the same or different and represents the average number of added moles of the oxyalkylene group, and is a number of 5 to 1000. m is an integer of 1 to 50.) A process for producing a multi-branched polyalkylene glycol polymer, comprising a step of polymerizing a vinyl monomer component in the presence of. The method for producing a multi-branched polyalkylene glycol polymer according to claim 9, wherein a carbon radical generator is used in the polymerization step. A polymer containing a polyalkylene glycol chain and having a multi-branched structure,
A multi-branched polyalkylene glycol polymer obtained by polymerizing a vinyl monomer component in the presence of the polyalkylene glycol chain-containing compound represented by the general formula (5). A cement admixture comprising the multi-branched polyalkylene glycol polymer according to any one of claims 1 to 8. A cement composition comprising the cement admixture according to claim 12.