JP2013001819A - Polymer and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polymer composition obtained by graft-polymerizing a carboxylic monomer with a polyalkylene glycol compound, in which the content of the polyalkylene glycol compound with which the carboxylic monomer is not grafted is reduced.SOLUTION: The method essentially includes a step of graft-polymerizing the monomer at 125-150°C in the presence of a polymerization initiator and a polyoxyalkylene compound. The polyoxyalkylene compound has a main chain terminal structure selected from aryl, alkyl, alkenyl and hydroxyl, and the content thereof is 1-30 mass% relative to 100 mass% of the polymer composition. The composition ratio of the monomer is 75-99 mol% of a monocarboxylic monomer (a) to 1-25 mol% of a dicarboxylic monomer (b). The polymerization initiator is an organic oxide having a 10-h half-life period of 80-100°C. The content of the dicarboxylic monomer to 100 mass% of the polymer composition is 1-10,000 ppm.

Description

  The present invention relates to a polymer and a method for producing the same.

  Conventionally, polymers obtained by graft polymerization of carboxylic acid monomers to polyalkylene glycols are known.

For example, U.S. Patent No. 6,057,049 includes a graft component bonded to one carbon atom that is at least 20 wt% hydrophilic, based on the weight of the graft polymer, and the graft component and 2 to 200 -C. A water-soluble or water-dispersible graft weight having at least one hydrophobic residue bonded via a polyether glycol chain having a (-) _2- C (-) _2- O- group Coalescence is disclosed. Further, in Patent Document 1, the graft polymer is a monomer having a polymerizable hydrophilic group in which the grafted side chain structural element is ethylenically unsaturated, such as a monomer sulfonic acid or preferably a carboxylic acid or an anhydride thereof. It is disclosed that the product is derived from. It is disclosed that the graft polymer can be used in various applications such as padding dyeing assistants, fiber assistants, wetting agents, detergents, antifoaming agents or paper venting agents.

For example, Patent Document 2 discloses that a polyether compound (A) having ethylene oxide as a constituent unit of 80 mol% or more and a number average molecular weight of 200 or more, (meth) acrylic acid (b1) of 40 to 100 mol%, and other copolymerizable compounds. Water-soluble graft polymer obtained by graft polymerization of monomer component (B) consisting of 0 to 60 mol% of monoethylenically unsaturated monomer (b2) in an amount of 25 wt% or more with respect to polyether compound (A) In obtaining water, the monomer component (B) is subjected to a graft polymerization reaction at a temperature of 100 ° C. or higher in the presence of a polymerization initiator in the presence of a polymerization initiator. A method for producing a conductive graft polymer is disclosed.
According to the production method described above, a monoethylenically unsaturated monomer mainly composed of (meth) acrylic acid has a high carboxylic acid density and is not grafted to the polyether. It is disclosed that a water-soluble graft polymer with a small amount of monoethylenically unsaturated monomer polymer can be produced efficiently.

  For example, in Patent Document 3, 10 to 90 mol% of monoethylenically unsaturated monocarboxylic acid, 10 to 90 mol% of monoethylenically unsaturated dicarboxylic acid and other monoethylenically unsaturated monomer capable of copolymerization are added to polyalkylene glycol. In a hydrophilic graft polymer obtained by graft polymerization of a monomer component consisting of 0 to 80 mol% of the product, the content of the monoethylenically unsaturated monocarboxylic acid is 900 ppm or less, and the hue (b value) of the 50 wt% aqueous solution ) Is 10 or less, a hydrophilic graft polymer is disclosed. It is disclosed that the polymer is a polymer that is less colored and has reduced residual monomers (particularly monoethylenically unsaturated monocarboxylic acid).

  For example, Patent Document 4 discloses a polymer composition obtained by polymerizing a polyoxyalkylene compound and an acid group-containing unsaturated monomer in the presence of a polymerization initiator, the polyoxyalkylene compound. Has at least one of an aryl group having less than 8 carbon atoms, an alkyl group having less than 8 carbon atoms, and an alkenyl group having less than 8 carbon atoms and / or two or more hydroxyl groups, and the polyoxyalkylene compound is It has an oxyalkylene group, and the content of the structure derived from the oxyalkylene group per 1 mol of the polyoxyalkylene compound is 10 to 400 mol, and the structure derived from the polyoxyalkylene compound and the acid group-containing unsaturated simple substance. The mass ratio to the structure derived from the monomer is 95: 5 to 50:50, and at least one selected from the following compounds 1 to 3 is used as the acid group-containing unsaturated compound. Mer relative to 100 parts by weight, containing 0.3 to 20 parts by weight, the polymer composition is disclosed. In the polymer composition, the residual amount of the polyoxyalkylene compound to which the acid group-containing monomer is not grafted is reduced, that is, the yield of the graft is improved and the uniformity of the composition is improved. It is disclosed that the stability over time of the composition is improved.

JP 59-62614 A JP 7-53645 A JP 2001-226441 A JP 2010-209136 A

As described above, various polymers obtained by graft polymerization of a carboxylic acid monomer to a polyalkylene glycol compound have been reported, but there is room for further improvement of physical properties as the demand for the graft polymer increases. there were. Specifically, if the graft polymer contains a large amount of polyalkylene glycol compounds that are not grafted with an acid group-containing monomer as an impurity, it may adversely affect the physical properties depending on the application, or the polymer may be stored in a solution. In this case, there is a demand for further reduction of these impurities as compared with the prior art.
Therefore, the present invention provides a polymer (composition) obtained by graft polymerization of a carboxylic acid monomer to a polyalkylene glycol compound, and the content of the polyalkylene glycol compound in which the carboxylic acid monomer is not grafted. It is an object of the present invention to provide a polymer (composition) having a lower content than in the prior art (in which the yield of the graft product is improved as compared with the prior art).

  The present inventors have intensively studied to solve the above problems. As a result, the present inventors can increase the yield of the graft polymer by performing the graft polymerization under the condition of performing polymerization using a specific polymerization initiator under specific conditions. It was found that the storage stability of the polymer (composition) was improved by setting the polymer composition to a predetermined one, and the present invention was completed.

  That is, the polymer composition of the present invention comprises a polymer containing a polymer produced by essentially polymerizing a monomer at 125 ° C. or higher and 150 ° C. or lower in the presence of a polymerization initiator and a polyoxyalkylene compound. The polyoxyalkylene compound has a structure in which the main chain terminal structure is selected from an aryl group having 7 or less carbon atoms, an alkyl group having 7 or less carbon atoms, an alkenyl group having 7 or less carbon atoms, and a hydroxyl group. In the polymer, the structural unit (a) derived from the monocarboxylic acid monomer is 75 mol% or more and 99 mol% or less with respect to 100 mol% of the structural unit derived from all monomers. Having a structural unit (b) derived from a monomer based on 100 mol% of structural units derived from all monomers, not less than 1 mol% and not more than 25 mol%, and the polymerization initiator has a 10-hour half-life temperature Is 80 ° C. or higher, 100 It is the following organic peroxide, the content of the polyoxyalkylene compound with respect to 100% by mass of the polymer composition is 1 to 30% by mass, and the dicarboxylic acid type monomer with respect to 100% by mass of the polymer composition It is a polymer composition whose body content is 1-10000 ppm.

  The polymer (composition) of the present invention can reduce the content of a polyalkylene glycol compound to which a carboxylic acid monomer has not been grafted. Moreover, since the polymer (composition) of the present invention is excellent in compatibility with a polyalkylene glycol compound and the like, it has excellent storage stability.

Hereinafter, the present invention will be described in detail.
[Polyoxyalkylene compounds]
The polymer of the present invention is a polymer produced by essentially including a step of polymerizing a monomer in the presence of a polyoxyalkylene compound. The “polymer of the present invention” includes unreacted polyoxyalkylene compounds.
In the present invention, the polyoxyalkylene compound is a structure in which the main chain terminal structure is selected from an aryl group having 7 or less carbon atoms, an alkyl group having 7 or less carbon atoms, an alkenyl group having 7 or less carbon atoms, and a hydroxyl group, and And a compound containing an oxyalkylene group as a structural unit. Examples of the oxyalkylene group include an oxyalkylene group having 2 to 7 carbon atoms, and specific examples include an oxyethylene group, an oxypropylene group, and an oxybutylene group.

The polyoxyalkylene compound in the present invention, an oxyethylene group _{(-O-CH 2 -CH 2 -} ) preferably contains a, those composed mainly of oxyethylene group is particularly preferred. In this case, “mainly composed of oxyethylene groups” means that when two or more oxyalkylene groups are present in the monomer, the oxyethylene groups occupy most of the total number of oxyalkylene groups present. It means that. Thereby, the grafting reaction to the polyoxyalkylene compound is likely to proceed during the polymerization of the monomer, and an excellent effect of improving water solubility and the like can be obtained. The oxyethylene group is more preferably 50 to 100 mol%, further preferably 80 mol% or more, more preferably 90 mol, based on 100 mol% of all oxyalkylene groups of the polyoxyalkylene compound in the present invention. % Or more is particularly preferable, and 100 mol% is most preferable.

As the polyoxyalkylene compound in the present invention, those obtained by polymerizing alkylene oxide by a known method or the like in the presence of a compound serving as a polymerization starting point are preferable. As a compound used as the starting point of the said polymerization, water, alcohol, ammonia, an amine etc. can be mentioned, for example, These are used 1 type or 2 or more types. Of these, at least one selected from water, alcohol and amine is preferred.
Examples of the alkylene oxide include ethylene oxide (EO), propylene oxide (PO), butylene oxide, and the like.
Examples of the alcohol include primary aliphatic alcohols having 1 to 7 carbon atoms such as methanol, ethanol, n-propanol, n-butanol and benzyl alcohol; aromatic alcohols such as phenol and methylphenol; Secondary alcohols; tertiary alcohols such as tert-butanol; diols such as ethylene glycol, diethylene glycol and propylene glycol; triols such as glycerin and trimethylolpropane; polyols such as sorbitol, etc. 1 type (s) or 2 or more types are used.

  The method for polymerizing alkylene glycol in the presence of the compound serving as the starting point of the polymerization is not particularly limited. (I) Strong alkalis such as alkali metal hydroxides and alcoholates, alkylamines and the like as base catalysts. Anionic polymerization used, (ii) Cationic polymerization using metal and metalloid halides, mineral acids, acetic acid, etc. as catalysts, and (iii) Alkoxides of metals such as aluminum, iron, zinc, alkaline earth compounds, Lewis acids Coordination polymerization using a combination of these can be used.

  As the polyoxyalkylene compound in the present invention, the terminal hydroxyl group of the polyoxyalkylene compound obtained by the above polymerization was reacted with a compound having a carboxyl group, an ester group, an isocyanate group, an amino group, a halogen group or the like. Polyoxyalkylene compounds may be used.

  Preferred examples of the polyoxyalkylene compound in the present invention include those having the structure of the following general formula (1).

In the general formula (1), R is a hydrogen atom, an aryl group having 7 or less carbon atoms, an alkyl group having 7 or less carbon atoms, and an alkenyl group having 8 or less carbon atoms. The alkyl group or alkenyl group may be linear or branched. The aryl group, alkyl group and alkenyl group may be substituted with other organic groups as long as the carbon number is within the above range.
In the said General formula (1), X is a carbonyl group, p represents the number of X presence, and is 0-1. It is more preferable that p is 0 (that is, X does not exist).
In the above general formula (1), Y represents —O—R ₁ — group, —S—R ₂ — group, — (O═) S (═O) —R ₃ — group, —N (—R ₅ ). -R ₄ - represents any one group. Here, R _{1 to} R ₄ each independently represents an alkylene group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, more preferably 2 to 3 carbon atoms, and most preferably 2 carbon atoms. R ₅ represents a hydrogen atom, an alkyl group having 7 or less carbon atoms, or a group represented by the following general formula (2):

It is. In the formula (2), R ₆ and R ₇ are each independently an alkylene group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, more preferably 2 to 3 carbon atoms, and most preferably 2 carbon atoms. Represent. Moreover, s is 0-100, Preferably it is 0-50, More preferably, it is 0-30. Incidentally, suppose that s is 2 or more, may be present alone by itself as R _7, or two or more may be mixed.

In the above general formula (1), Z represents an oxyalkylene group. Examples and preferred embodiments of the oxyalkylene group are as described above. As described above, only one type of Z may be present alone, or two or more types may be mixed.
In the general formula (1), q represents the number of Z repetitions. q is preferably 3 to 300, more preferably 5 to 200, and still more preferably 10 to 99.

  In the said General formula (1), r is an integer of 1-6. When r is 2 or more, it means that a group represented by parentheses in the above formula (1) is directly bonded to R by the number r. r is preferably 1 to 4, more preferably 1 to 2, and most preferably 1.

  The number average molecular weight of the polyoxyalkylene compound in the present invention is preferably 100 or more, and more preferably 200 or more. When the number average molecular weight is less than 100, there is a problem in that the graft ratio decreases and the amount of unreacted polyoxyalkylene compounds increases. The upper limit of the number average molecular weight is not particularly limited, but is preferably 100,000 or less. When the number average molecular weight exceeds 100,000, the viscosity tends to increase and it becomes difficult to handle during polymerization.

  The polymer of the present invention comprises a structural unit derived from a polyoxyalkylene compound (a structural part other than a structural unit derived from a monomer contained in a copolymer with a monomer, and an unreacted polyoxyalkylene compound). Compound), a structural unit derived from a polyoxyalkylene compound and a structural unit derived from all monomers (a structural unit derived from a monocarboxylic acid monomer, a structural unit derived from a dicarboxylic acid monomer, And a structural unit derived from other monomers) is preferably 60 to 90% by mass with respect to 100% by mass in total. More preferably, it is 65-85 mass%, More preferably, it is 70-80 mass%. By being in the above range, for example, when the polymer of the present invention is used as a water treatment agent, the gel resistance is good.

[Structural units derived from monomers]
In the polymer of the present invention, the structural unit (a) derived from the monocarboxylic acid monomer is 75 mol% or more and 99 mol% or less with respect to 100 mol% of the structural unit derived from all monomers. The structural unit (b) derived from the system monomer has 1 mol% or more and 25 mol% or less with respect to 100 mol% of the structural unit derived from all monomers.

<Structural Unit (a) Derived from Monocarboxylic Acid Monomer>
In the present invention, the monocarboxylic acid monomer (also referred to as monomer (A)) is a monomer having one carboxyl group or one carboxyl group salt per molecule. The said salt represents a metal salt, ammonium salt, and an amine salt.
Specific examples of the monocarboxylic acid monomer include acrylic acid, methacrylic acid, crotonic acid, isocrotonic acid, α-hydroxyacrylic acid, and salts thereof. Among the monocarboxylic acid monomers, the polymerizability is high, the residual monomer can be reduced, and the dispersibility of the inorganic particles of the resulting polymer is improved. More preferred are monomers selected from acids and salts thereof. One of these monocarboxylic acid monomers may be used alone, or two or more of them may be used in combination.

The structural unit (a) derived from the monocarboxylic acid monomer is a structure in which the polymerizable unsaturated double bond of the monocarboxylic acid monomer is a single bond. When the monomer is sodium acrylate, the structural unit (a) can be represented by —CH ₂ —CH (COONa) —. The polymer of the present invention has “structural unit (a) derived from monocarboxylic acid monomer” means that the finally obtained polymer is not polymerizable with the monocarboxylic acid monomer. It is meant to include structural units in which saturated double bonds are replaced with single bonds.

The polymer of the present invention has a structural unit (a) derived from a monocarboxylic acid monomer at a ratio of 75 mol% to 99 mol% with respect to 100 mol% of the structure derived from all monomers. In the present invention, the structure derived from all monomers refers to a structural unit (a) derived from a monocarboxylic acid monomer, a structural unit (b) derived from a dicarboxylic acid monomer, and other monomers. The structural unit (e) derived from
When the structural unit (a) derived from the monocarboxylic acid monomer is within the above range, the dispersibility of the inorganic particles of the polymer tends to be excellent. The ratio of the structural unit (a) to 100 mol% of the structure derived from all monomers is preferably 78 mol% or more and 98 mol% or less, more preferably 80 mol% or more and 97 mol% or less, Preferably they are 85 mol% or more and 95 mol% or less.

<Structural unit (b) derived from dicarboxylic acid monomer>
In the present invention, the dicarboxylic acid monomer (also referred to as monomer (B)) is a monomer having a total of two carboxyl groups and / or salts of carboxyl groups per molecule. The said salt represents a metal salt, ammonium salt, and an amine salt.
Specific examples of the dicarboxylic acid monomer include maleic acid, itaconic acid, fumaric acid, 2-methyleneglutaric acid, and salts thereof (including the case where only one carboxyl group is in a salt form). Is done. Among the dicarboxylic acid monomers, it is easy to proceed with graft polymerization, and the compatibility of the resulting polymer with the remaining polyalkylene glycol compound in which the carboxylic acid monomer is not grafted is particularly improved. Therefore, the monomer is preferably selected from maleic acid and maleic acid salts.

  The structural unit (b) derived from the dicarboxylic acid monomer is a structure in which the polymerizable unsaturated double bond of the dicarboxylic acid monomer is a single bond. In the case of monosodium maleate, the structural unit (b) can be represented by —CH (COOH) —CH (COONa) —. The polymer of the present invention has the “structural unit (b) derived from a dicarboxylic acid monomer” that the polymer finally obtained is a polymerizable unsaturated dicarboxylic acid monomer. It is meant to include structural units in which a heavy bond is replaced with a single bond.

The polymer of the present invention has the structural unit (b) derived from the dicarboxylic acid monomer at a ratio of 1 mol% to 25 mol% with respect to 100 mol% of the structure derived from all monomers. In the present invention, the structure derived from all monomers refers to a structural unit (a) derived from a monocarboxylic acid monomer, a structural unit (b) derived from a dicarboxylic acid monomer, and other monomers. The structural unit (e) derived from
When the structural unit (b) derived from the dicarboxylic acid monomer is within the above range, the resulting polymer phase with the remaining polyalkylene glycol compound to which the carboxylic acid monomer was not grafted. By particularly improving the solubility, the stability over time tends to be excellent when the polymer is stored in the form of a solution. The ratio of the structural unit (b) to 100 mol% of the structure derived from all monomers is preferably 2 mol% or more and 22 mol% or less, more preferably 3 mol% or more and 20 mol% or less, Preferably they are 5 mol% or more and 15 mol% or less.

<Structural unit derived from other monomer (e)>
The polymer of the present invention has structural units (e) derived from other monomers at a ratio of 0 mol% or more and 20 mol% or less with respect to 100 mol% of the structure derived from all monomers. Also good. In the present invention, the structure derived from all monomers is as described above. When the structural unit (e) derived from the other monomer exceeds the above range, the dispersibility of the inorganic particles of the polymer and the temporal stability of the polymer tend to decrease, which is not preferable. The proportion of the structural unit (e) with respect to 100 mol% of the structure derived from all monomers is preferably 0 mol% or more and 18 mol% or less, more preferably 0 mol% or more and 15 mol% or less, particularly preferably. It is 0 mol% or more and 10 mol% or less.

The other monomer (E) is not particularly limited and is appropriately selected depending on the desired effect (however, the above polyoxyalkylene compound, monomer (A), monomer (B) Is not included in the other monomer (E)). Specifically, unsaturated carboxylic acid monomers other than the above monomers (A) and (B); vinyl sulfonic acid, 1-acrylamido-1-propanesulfonic acid, 2-acrylamido-2-propanesulfonic acid 2- (meth) acrylamide-2-methyl-1-propanesulfonic acid, (meth) allyloxybenzenesulfonic acid, styrenesulfonic acid, sulfoethyl (meth) acrylate, sulfopropyl (meth) acrylate, (meth) allylsulfonic acid Sulfonic acid group-containing monomers such as isoprenesulfonic acid, 3-allyloxy-2-hydroxy-1-propanesulfonic acid, and salts thereof; N-vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N -Vinyl-N-methylformamide, N-vinyl-N-methylacetamide, N- N-vinyl monomers such as niloxazolidone; amide monomers such as (meth) acrylamide, N, N-dimethylacrylamide and N-isopropylacrylamide; allyl ether monomers such as (meth) allyl alcohol; isoprenol , Etc .; (Meth) acrylic acid alkyl ester monomers such as butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dodecyl (meth) acrylate; hydroxyethyl (meth) acrylate, 2 -Hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, α-hydroxymethylethyl (meth) acrylate , Hydroxypentyl (meth) acrylate, hydroxyneopentyl (meth) acrylate, hydroxyhexyl (meth) acrylate and other (meth) acrylate hydroxyalkyl monomers; styrene, indene, vinylaniline and other vinyl aryl monomers , Isobutylene, vinyl acetate; vinyl aromatic amino group-containing monomers having a heterocyclic aromatic hydrocarbon group and amino group such as vinyl pyridine and vinyl imidazole, and quaternized products and salts thereof; dimethylaminoethyl acrylate Aminoalkyl (meth) acrylates such as dimethylaminoethyl methacrylate, dimethylaminopropyl acrylate and aminoethyl methacrylate, and quaternized products and salts thereof; allylamines such as diallylamine and diallyldimethylamine; (I) Dialkyl such as dimethylamine, diethylamine, diisopropylamine, di-n-butylamine, etc. on the epoxy ring of (i) (meth) allyl glycidyl ether, isoprenyl glycidyl ether, vinyl glycidyl ether Monomers obtained by reacting amines such as amines, alkanolamines such as diethanolamine and diisopropanolamine, aminocarboxylic acids such as iminodiacetic acid and glycine, and cyclic amines such as morpholine and pyrrole, and quaternized products thereof Salt and the like.
Moreover, the said other monomer (E) may be used individually by 1 type, or may be used with the form of a 2 or more types of mixture.

[Acid amount of polymer]
It is preferable that the polymer of this invention is 1-40 mass% with respect to the sum total of the structural unit derived from the polyoxyalkylene type compound and the structural unit derived from all the monomers. When the acid amount is within the above range, the dispersibility of the inorganic particles tends to be improved. The acid amount is a numerical value measured by the method described in Examples described later.

[Polymerization initiator]
The polymer of the present invention is a polymer produced by essentially including a step of polymerizing a monomer in the presence of a polymerization initiator and a polyoxyalkylene compound. The polymerization initiator is an organic peroxide having a 10-hour half-life temperature of 80 ° C. or higher and 100 ° C. or lower. When the polymerization initiator has the above half-life temperature, the yield of the polymer tends to be improved.
Examples of the organic peroxide include t-butyl peroxyisopropyl monocarbonate (10-hour half-life temperature 98.7 ° C.), t-butyl peroxylaurate (10-hour half-life temperature 98.3 ° C.), and the like. Is done. T-Butylperoxyisopropyl monocarbonate is most preferred because the yield of the polymer is better and the reaction rate of the dicarboxylic acid monomer tends to be improved.
The 10-hour half-life temperature is a numerical value calculated by thermal decomposition in benzene at a peroxide concentration of 0.10 mol / L.

  The amount of the organic peroxide used in the production of the polymer of the present invention is preferably 1 to 15% by mass, more preferably 2 to 12%, based on 100% by mass of all monomers used for graft polymerization. It is mass%, More preferably, it is 3-10 mass%.

  In the production of the polymer of the present invention, other polymerization initiators may be used in addition to the organic peroxide. Examples of other polymerization initiators include hydrogen peroxide, other organic peroxides, persulfates, and azo compounds.

[Polymerization temperature]
The polymer of the present invention is a polymer produced by essentially performing a step of polymerizing a monomer at 125 ° C. or higher and 150 ° C. or lower in the presence of a polymerization initiator and a polyoxyalkylene compound.
Polymerization in the above temperature range tends to improve the yield of the polymer.
The lower limit of the polymerization temperature is preferably 126 ° C. or higher, more preferably 127 ° C. or higher, and the upper limit of the polymerization temperature is preferably 145 ° C. or lower, more preferably 140 ° C. or lower.
The polymerization step (polymerization step) may be set so as to be within the above temperature range during a part of the time, but the polymerization time (in the case of proceeding polymerization while adding the monomer, The time during which the polymerization initiator is added and when the polymerization proceeds while adding the polymerization initiator in one batch, the time during which the polymerization initiator is added is referred to as the monomer and the polymerization initiator. When the polymerization is carried out by adding all together, it is preferably maintained within the above temperature range for a time period of 50% or more of the heating time), and is maintained within the above temperature range for a time period of 80% or more. It is more preferable that the temperature is maintained within the above temperature range in a time zone of 100% of the polymerization time.
In addition, you may set to the said temperature range also in time slots (before polymerization start or after polymerization start) other than polymerization time.

[Molecular weight of polymer]
The weight average molecular weight of the polymer of the present invention can be appropriately set in consideration of the desired performance in each application, and is not particularly limited, but the weight average molecular weight of the graft polymer of the present invention is specifically, Preferably it is 100-50000, More preferably, it is 500-30000, More preferably, it is 1000-20000. When the value of the weight average molecular weight is too large, the viscosity becomes high and handling may be complicated. On the other hand, if the value of the weight average molecular weight is too small, the dispersibility of the inorganic fine particles tends to decrease. In addition, as a value of the weight average molecular weight of the polymer of this invention, the value measured by the method as described in the Example mentioned later shall be employ | adopted.

[Polymer composition]
The polymer composition of the present invention essentially contains the polymer of the present invention. In addition, raw material residues and by-products of the polymerization reaction such as unreacted acid group-containing unsaturated monomer, unreacted polymerization initiator, and polymerization initiator decomposition product may be included.
The polymer composition of this invention contains a solvent as needed. As a solvent, what contains water as an essential thing is preferable, and it is more preferable that it is water. When the polymer composition of the present invention contains a solvent such as water, the content of the solvent may be 10% by mass to 99% by mass with respect to 100% by mass of the polymer composition from the viewpoint of handleability. preferable.

<Content of polyoxyalkylene compound>
The polymer composition of the present invention is characterized in that the content of the polyoxyalkylene compound is 1 to 30% by mass with respect to 100% by mass of the polymer composition (solid content conversion). When the content of the polyoxyalkylene compound is within the above range, the storage stability (particularly the separation stability when stored as an aqueous solution) is improved.
The content of the polyoxyalkylene compound relative to 100% by mass of the polymer composition (in terms of solid content) is preferably 3 to 28% by mass, and more preferably 5 to 25% by mass.
A copolymer of a polyoxyalkylene compound and a monocarboxylic acid monomer and / or a dicarboxylic acid monomer is not a “polyoxyalkylene compound” and is referred to here. The “polyoxyalkylene compound” is usually a polyoxyalkylene compound remaining unreacted with a monocarboxylic acid monomer and / or a dicarboxylic acid monomer.

[Content of dicarboxylic acid monomer]
The polymer composition of the present invention is characterized in that the content of the dicarboxylic acid monomer is 0 to 10,000 ppm with respect to 100% by mass of the polymer composition (in terms of solid content). When the content of the dicarboxylic acid monomer is in the above range, the storage stability is improved.
The content of the dicarboxylic acid monomer with respect to 100% by mass of the polymer composition (in terms of solid content) is preferably 0 to 5000 ppm, and more preferably 0 to 3000 ppm.

[Production Method of Polymer (Composition)]
In the present invention, the production method of the polymer (composition) is not particularly limited unless otherwise specified, and can be produced by appropriately referring to conventionally known knowledge. Preferably, the polymerization is carried out in the form of substantially bulk polymerization (bulk polymerization), specifically, the solvent content is 10% by mass or less based on the total amount of the reaction system. In this case, conventionally known knowledge relating to bulk polymerization (bulk polymerization) can be referred to as appropriate, and further improved as necessary.

In the method for producing the polymer (composition) of the present invention, the polymerization may be started in a state where a part or all of the polyoxyalkylene compound is charged into the reaction system. From the viewpoint of facilitating the graft polymerization based on the polyoxyalkylene compound, it is particularly preferable to start the polymerization in a state where the entire amount of the polyoxyalkylene compound used is charged in the reaction system.
In the method for producing a polymer (composition) of the present invention, polymerization is carried out while adding part or all of the monomer component and the polymerization initiator to the reaction system (that is, added to the reaction system after the start of polymerization). good. Specifically, it is preferable to carry out the polymerization while adding the entire amount of the monocarboxylic acid monomer to the reaction system. On the other hand, it is preferable to start the polymerization with the dicarboxylic acid monomer charged in the reaction system. The polymerization initiator is preferably polymerized while adding the entire amount to the reaction system.
As a preferred embodiment, the whole amount of the polyoxyalkylene compound and the dicarboxylic acid monomer is charged into the reaction system, the reaction system is heated to dissolve the dicarboxylic acid monomer in the polyoxyalkylene compound, and then the rest The monomer component (monocarboxylic acid monomer and other monomer if necessary) and a polymerization initiator are separately added to cause the polymerization reaction to proceed. According to such a form, since the molecular weight of the polymer obtained can be adjusted easily, it is preferable. In addition, superposition | polymerization may be performed by a batch type and may be performed by a continuous type.

In the method for producing a polymer (composition) of the present invention, the amount of the polyoxyalkylene compound used is 60 to 90% by mass with respect to 100% by mass of the total mass of the polyoxyalkylene compound and the monomer. It is preferable to do. More preferably, it is 65-85 mass%, More preferably, it is 70-80 mass%.
It is preferable that the usage-amount of a monomer shall be 10 to 40 mass% with respect to 100 mass% of the total mass of a polyoxyalkylene type compound and a monomer. More preferably, they are 15 mass% or more and 35 mass% or less, More preferably, they are 20 mass% or more and 30 mass% or less.
It is preferable that the usage-amount for a monocarboxylic acid-type monomer shall be 75 mol% or more and 99 mol% or less with respect to 100 mol% of the usage-amount of all the monomers. More preferably, they are 78 mol% or more and 98 mol% or less, More preferably, they are 80 mol% or more and 97 mol% or less, Especially preferably, they are 85 mol% or more and 95 mol% or less.
The amount used for the dicarboxylic acid monomer is preferably 1 mol% or more and 25 mol% or less with respect to 100 mol% of the total monomer used. More preferably, they are 2 mol% or more and 22 mol% or less, More preferably, they are 3 mol% or more and 20 mol% or less, Especially preferably, they are 5 mol% or more and 15 mol% or less.
It is preferable that the usage-amount for another monomer shall be 0-20 mol% with respect to 100 mol% of the usage-amount of all the monomers. More preferably, they are 0 mol% or more and 18 mol% or less, More preferably, they are 0 mol% or more and 15 mol% or less, Especially preferably, they are 0 mol% or more and 10 mol% or less.

  In the method for producing a polymer (composition) of the present invention, the polymerization time is not particularly limited, but is preferably 30 to 420 minutes, more preferably 45 to 390 minutes, and further preferably 60 to 360 minutes. Most preferably, it is 90 to 240 minutes. In the present invention, the “polymerization time” is as described above.

  The pressure in the reaction system may be any of normal pressure (atmospheric pressure), reduced pressure, and increased pressure, but from the viewpoint of the molecular weight of the polymer obtained, the reaction system is sealed under normal pressure. However, it is preferably performed under pressure. Moreover, it is preferable to carry out under normal pressure (atmospheric pressure) in terms of equipment such as a pressurizing device, a decompressing device, a pressure-resistant reaction vessel, and piping. The atmosphere in the reaction system may be an air atmosphere, but is preferably an inert atmosphere. For example, the inside of the system is preferably replaced with an inert gas such as nitrogen before the start of polymerization.

As above-mentioned, Preferably the usage-amount of a solvent is 10 mass% or less with respect to the whole quantity of a reaction system. The amount of the solvent used is more preferably 7% by mass or less, further preferably 5% by mass or less, and particularly preferably 3% by mass or less. From the viewpoint of improving the graft ratio of the resulting polymer, Most preferably, it is substantially free of solvent. “Substantially free of solvent” means a form in which no solvent is positively added during graft polymerization, and it means that mixing of a solvent to the extent of impurities is acceptable.
On the other hand, by carrying out the polymerization reaction under the reflux of an organic solvent, it is possible to suppress the adhesion of gel deposits to the wall surface or upper part in the reactor. From such a viewpoint, it is preferable to use a small amount of an organic solvent.

  When the reaction system contains a solvent, the solvent used is not particularly limited, but those having a small chain transfer constant of the monomer component to the solvent, those having a boiling point of 70 ° C. or higher that can be used under normal pressure, and the like are preferable. Examples of such solvents include isobutyl alcohol, n-butyl alcohol, tert-butyl alcohol, isopropyl alcohol, ethylene glycol, diethylene glycol, glycerin, triethylene glycol, propylene glycol, ethylene glycol monoalkyl ether, propylene glycol monoalkyl ether. Alcohols such as ethylene glycol dialkyl ethers, diethers such as propylene glycol dialkyl ethers; acetic acid such as acetic acid, ethyl acetate, propyl acetate, butyl acetate, acetates of ethylene glycol monoalkyl ether, acetates of propylene glycol monoalkyl ether, etc. System compounds; and the like. Only 1 type of these solvents may be used independently, and 2 or more types may be used together. Examples of the alkyl group in the alcohols and diethers include a methyl group, an ethyl group, a propyl group, and a butyl group.

In the method for producing a polymer (composition) of the present invention, in addition to the polymerization initiator described above, a decomposition catalyst for the polymerization initiator or a reducing compound may be added to the reaction system.
Examples of the decomposition catalyst for the polymerization initiator include metal halides such as lithium chloride and lithium bromide; metal oxides such as titanium oxide and silicon dioxide; hydrochloric acid, hydrobromic acid, perchloric acid, sulfuric acid, nitric acid and the like. Metal salts of inorganic acids; carboxylic acids such as formic acid, acetic acid, propionic acid, lactic acid, isolacic acid, benzoic acid, their esters and their metal salts; heterocyclic amines such as pyridine, indole, imidazole, carbazole and their derivatives Can be mentioned. These decomposition catalysts may be used alone or in combination of two or more.

  Examples of the reducing compound include organic metal compounds such as ferrocene; iron naphthenate, copper naphthenate, nickel naphthenate, cobalt naphthenate, manganese naphthenate, and the like, such as iron, copper, nickel, cobalt, and manganese. Inorganic compounds capable of generating metal ions; boron trifluoride ether adducts, potassium permanganate, perchloric acid and other inorganic compounds; sulfur dioxide, sulfite, sulfate, bisulfite, thiosulfate, sulfoxide, Sulfur-containing compounds such as benzenesulfinic acid and its substitutes, and homologues of cyclic sulfinic acid such as p-toluenesulfinic acid; octyl mercaptan, dodecyl mercaptan, mercaptoethanol, α-mercaptopropionic acid, thioglycolic acid, thiopropionic acid, α -Sodium thiopropionate sulfopropyl es Tercap, mercapto compounds such as α-thiopropionic acid sodium sulfoethyl ester; nitrogen-containing compounds such as hydrazine, β-hydroxyethylhydrazine, hydroxylamine; formaldehyde, acetaldehyde, propionaldehyde, n-butyraldehyde, isobutyraldehyde, isovaleraldehyde Aldehydes such as ascorbic acid and the like. These reducing compounds may also be used alone or in combination of two or more. A reducing compound such as a mercapto compound may be added as a chain transfer agent.

In the method for producing a polymer (composition) of the present invention, an aging step may be provided in addition to the step of polymerizing monomers (polymerization step).
The aging step can be carried out, for example, by aging after completion of dropping of the monomer while maintaining the polymerization temperature or changing the polymerization temperature. By including the aging step, the residual monomer can be reduced. On the other hand, the color tone of the polymer (composition) tends to deteriorate. Considering the economical aspect, it is better that the aging time is short. For example, the aging step is preferably 30 minutes to 6 hours, and more preferably 1 to 3 hours.

  The method for producing a polymer (composition) of the present invention may be provided with a post-treatment step in which the polymer composition is further dissolved in water and a peroxide is added in addition to or in place of the aging step. good. By providing the post-treatment step, it is possible to reduce the residual monomer.

  The peroxide added in the post-treatment step is hydrogen peroxide; inorganic peroxide (peroxodisulfate (sodium persulfate, potassium persulfate, ammonium persulfate, etc.), peroxoborate, dithionite, sulfurous acid. Hydrogen peroxide, disulfite, etc.); organic peroxides (those exemplified as polymerization initiators, peracetic acid, peracetates (such as sodium peracetate), percarbonates (such as sodium percarbonate)) Water-soluble ones are preferable, water-soluble weak oxides are more preferable, and hydrogen peroxide is most preferable.

  When a peroxide is used in the post-treatment step, it is preferable to use a decomposition accelerator that can accelerate decomposition of the peroxide together with the peroxide. Examples of the decomposition accelerator include reducing agents such as amines, ascorbic acid and iron, and alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. One or more of these are used. be able to. As the decomposition accelerator, a reducing agent is preferable, and ascorbic acid is most preferable.

  When a peroxide or its decomposition accelerator is used in the post-treatment step, the total is preferably 0.01 to 10% by mass with respect to 100% by mass of the polymer. More preferably, it is 0.05-5 mass%, More preferably, it is 0.1-2 mass%.

  The method for producing a polymer (composition) of the present invention may further include a neutralization step, a dilution step, a concentration step, and a drying step.

[Use of polymer (composition)]
The polymer (or polymer composition) of the present invention comprises a water treatment agent, a scale inhibitor (scale inhibitor), a fiber treatment agent, a dispersant, a metal ion sealant, a thickener, various binders, an emulsifier, and skin care. It can be used as an agent, hair care agent, detergent composition and the like.

<Water treatment agent>
The polymer (or polymer composition) of the present invention can be used as a water treatment agent. If necessary, the water treatment agent may contain a polymerized phosphate, phosphonate, anticorrosive, slime control agent, and chelating agent as other compounding agents.

  The water treatment agent is useful for scale prevention in a cooling water circulation system, a boiler water circulation system, a seawater desalination apparatus, a reverse osmosis membrane treatment apparatus, a pulp digester, a black liquor concentration tank, and the like. Further, any appropriate water-soluble polymer may be included as long as it does not affect the performance and effects.

<Fiber treatment agent>
The polymer (or polymer composition) of the present invention can be used as a fiber treatment agent. The fiber treatment agent includes at least one selected from the group consisting of a dye, a peroxide, and a surfactant, and the polymer (or polymer composition) of the present invention.

  The content of the polymer of the present invention in the fiber treatment agent is preferably 1 to 100% by mass and more preferably 5 to 100% by mass with respect to the entire fiber treatment agent. Further, any appropriate water-soluble polymer may be included as long as the performance and effects are not affected.

  Below, the compounding example of the fiber processing agent which is closer to embodiment is shown. This fiber treatment agent can be used in the steps of refining, dyeing, bleaching and soaping in fiber treatment. Examples of dyeing agents, peroxides and surfactants include those usually used for fiber treatment agents.

  The blending ratio of the polymer of the present invention to at least one selected from the group consisting of a dye, a peroxide, and a surfactant is, for example, for improving the whiteness, color unevenness, and dyeing tempering degree of fibers. Is a fiber treatment agent in terms of a pure component, 0.1 to 100 parts by mass of at least one selected from the group consisting of a dye, a peroxide and a surfactant with respect to 1 part by mass of the polymer of the present invention. It is preferable to use the composition mix | blended in a ratio as a fiber processing agent.

  Arbitrary appropriate fiber can be employ | adopted as a fiber which can use the said fiber processing agent. Examples thereof include cellulosic fibers such as cotton and hemp, chemical fibers such as nylon and polyester, animal fibers such as wool and silk, semi-synthetic fibers such as human silk, and woven fabrics and blended products thereof.

  When the fiber treatment agent is applied to the refining process, it is preferable to blend the polymer of the present invention with an alkali agent and a surfactant. When applied to the bleaching step, it is preferable to blend the polymer of the present invention, a peroxide, and a silicic acid-based agent such as sodium silicate as a decomposition inhibitor for the alkaline bleaching agent.

<Inorganic pigment dispersant>
The polymer (or polymer composition) of the present invention can be used as an inorganic pigment dispersant. In the inorganic pigment dispersant, condensed phosphoric acid and its salt, phosphonic acid and its salt, and polyvinyl alcohol may be used as other compounding agents as required.

  The content of the polymer of the present invention in the inorganic pigment dispersant is preferably 5 to 100% by mass with respect to the whole inorganic pigment dispersant. Further, any appropriate water-soluble polymer may be included as long as it does not affect the performance and effect.

  The inorganic pigment dispersant can exhibit good performance as a dispersant for heavy or light calcium carbonate or clay inorganic pigment used in paper coating. For example, by adding a small amount of an inorganic pigment dispersant to an inorganic pigment and dispersing it in water, high concentration calcium carbonate having low viscosity and high fluidity and good aging stability of their performance. High concentration inorganic pigment slurries such as slurries can be produced.

  When the inorganic pigment dispersant is used as an inorganic pigment dispersant, the amount of the inorganic pigment dispersant used is preferably 0.05 to 2.0 parts by mass with respect to 100 parts by mass of the inorganic pigment. When the amount of the inorganic pigment dispersant used is within the above range, a sufficient dispersion effect can be obtained, and an effect commensurate with the addition amount can be obtained, which can be economically advantageous.

<Detergent composition>
The polymer (composition) of the present invention can also be added to a detergent composition.
Although the polymer (composition) of the present invention includes the above-described polymer, the content of the polymer is preferably relative to the total amount of the detergent composition from the viewpoint that excellent builder performance can be exhibited. Is 0.1 to 15% by mass, more preferably 0.3 to 10% by mass, and still more preferably 0.5 to 5% by mass.

  Detergent compositions used in detergent applications usually include surfactants and additives used in detergents. Specific forms of these surfactants and additives are not particularly limited, and conventionally known knowledge can be appropriately referred to in the detergent field. The detergent composition may be a powder detergent composition or a liquid detergent composition.

  The surfactant is one or more selected from the group consisting of an anionic surfactant, a nonionic surfactant, a cationic surfactant and an amphoteric surfactant. When two or more kinds are used in combination, the total amount of the anionic surfactant and the nonionic surfactant is preferably 50% by mass or more, more preferably 60% by mass with respect to the total amount of the surfactant. It is above, More preferably, it is 70 mass% or more, Most preferably, it is 80 mass% or more.

  Examples of the anionic surfactant include alkylbenzene sulfonate, alkyl ether sulfate, alkenyl ether sulfate, alkyl sulfate, alkenyl sulfate, α-olefin sulfonate, α-sulfo fatty acid or ester salt, alkane sulfonate. , Saturated fatty acid salt, unsaturated fatty acid salt, alkyl ether carboxylate, alkenyl ether carboxylate, amino acid type surfactant, N-acyl amino acid type surfactant, alkyl phosphate ester or salt thereof, alkenyl phosphate ester or Its salts are preferred. An alkyl group such as a methyl group may be branched from the alkyl group or alkenyl group in these anionic surfactants.

  Nonionic surfactants include polyoxyalkylene alkyl ethers, polyoxyalkylene alkenyl ethers, polyoxyethylene alkyl phenyl ethers, higher fatty acid alkanolamides or alkylene oxide adducts thereof, sucrose fatty acid esters, alkyl glycoxides, fatty acid glycerin monoesters. Esters, alkylamine oxides and the like are preferred. An alkyl group such as a methyl group may be branched from the alkyl group or alkenyl group in these nonionic surfactants.

  As the cationic surfactant, a quaternary ammonium salt or the like is suitable. As the amphoteric surfactant, a carboxyl type amphoteric surfactant, a sulfobetaine type amphoteric surfactant, and the like are suitable. The alkyl group and alkenyl group in these cationic surfactants and amphoteric surfactants may be branched from an alkyl group such as a methyl group.

  The blending ratio of the surfactant is usually 10 to 80% by mass, preferably 15 to 70% by mass, more preferably 20 to 60% by mass, and particularly preferably based on the total amount of the detergent composition. Is 25-40 mass%. If the surfactant content is too small, sufficient detergency may not be achieved, and if the surfactant content is too high, the economy may be reduced.

  Additives include anti-redeposition agents to prevent redeposition of contaminants such as alkali builders, chelate builders, sodium carboxymethylcellulose, stain inhibitors such as benzotriazole and ethylene-thiourea, soil release agents, and color transfer. Inhibitors, softeners, alkaline substances for pH adjustment, fragrances, solubilizers, fluorescent agents, colorants, foaming agents, foam stabilizers, polishes, bactericides, bleaching agents, bleaching aids, enzymes, dyes A solvent or the like is preferable. In the case of a powder detergent composition, it is preferable to blend zeolite.

  The detergent composition may include other detergent builders in addition to the polymer composition of the present invention. Examples of other detergent builders include, but are not limited to, alkali builders such as carbonates, hydrogen carbonates, and silicates, tripolyphosphates, pyrophosphates, bow glass, nitrilotriacetate, ethylenediaminetetraacetate, Examples thereof include acid salts, (meth) acrylic acid copolymer salts, acrylic acid-maleic acid copolymers, chelate builders such as fumarate and zeolite, and carboxyl derivatives of polysaccharides such as carboxymethylcellulose. Examples of the counter salt used in the builder include alkali metals such as sodium and potassium, ammonium and amine.

  The total blending ratio of the additive and other builder for detergent is usually preferably 0.1 to 50% by mass with respect to 100% by mass of the cleaning composition. More preferably, it is 0.2-40 mass%, More preferably, it is 0.3-35 mass%, Most preferably, it is 0.4-30 mass%, Most preferably, it is 0.5-20 mass% or less. It is. If the additive / other detergent builder content is less than 0.1% by mass, sufficient detergent performance may not be achieved, and if it exceeds 50% by mass, the economy may be reduced.

  In addition, the concept of the above-mentioned detergent composition includes specific detergents such as synthetic detergents for household detergents, textile industry and other industrial detergents, hard surface cleaners, and bleaching detergents that enhance one of the components. Also included are detergents that are only used.

  When the detergent composition is a liquid detergent composition, the amount of water contained in the liquid detergent composition is usually preferably 0.1 to 75% by mass, more preferably based on the total amount of the liquid detergent composition. Is 0.2 to 70% by mass, more preferably 0.5 to 65% by mass, even more preferably 0.7 to 60% by mass, particularly preferably 1 to 55% by mass, Preferably it is 1.5-50 mass%.

  When the detergent composition is a liquid detergent composition, the detergent composition preferably has a kaolin turbidity of 200 mg / L or less, more preferably 150 mg / L or less, and even more preferably 120 mg / L or less. Especially preferably, it is 100 mg / L or less, Most preferably, it is 50 mg / L or less.

  Further, the change (difference) in kaolin turbidity with and without adding the polymer composition of the present invention as a detergent builder to the liquid detergent composition is preferably 500 mg / L or less, more preferably It is 400 mg / L or less, more preferably 300 mg / L or less, particularly preferably 200 mg / L or less, and most preferably 100 mg / L or less. As the kaolin turbidity value, a value measured by the following method is adopted.

  The present invention will be described in more detail with reference to examples below, but the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.

<Molecular weight of polymer>
The weight average molecular weight (Mw) of the polymer was measured using gel permeation chromatography (GPC).
GPC measurement conditions:
Equipment: Hitachi L-7000 series detector: RI
Column: SHODEX Asahipak GF-310-HQ, GF-710-HQ, GF-1G 7B manufactured by Showa Denko KK
Column temperature: 40 ° C
Flow rate: 0.5 ml / min
Calibration curve: POLYACRYLIC ACID STANDARD made by Soka Science Co., Ltd.
Eluent: 0.1 M aqueous sodium acetate solution / acetonitrile = 75/25 (wt / wt).

<Measurement of residual monomer>
The residual monomer was quantified using liquid chromatography.
Measurement conditions for liquid chromatography:
Measuring device: 8020 series manufactured by Tosoh Corporation Column: CAPCELL PAK C1 UG120 manufactured by Shiseido Co., Ltd.
Temperature: 40.0 ° C
Eluent: 10 mmol / L Disodium hydrogen phosphate.12 hydrate aqueous solution (adjusted to pH 7 with phosphoric acid) / acetonitrile = 45/55 (volume ratio)
Flow rate: 1.0 ml / min
Detector: UV (detection wavelength 215 nm).

<Measurement of graft ratio>
The content (mass%) of the graft polymer in the polymer composition (in terms of solid content) was taken as the graft yield. That is, it is the ratio of the mass of the graft polymer contained in the polymer composition to the mass of the solid content of the polymer composition, and is calculated by the following formula.
100 (%)-(content of unreacted polyoxyalkylene compound in polymer composition (%) + monomer content in solid in polymer composition (%))
<Method for measuring solid content of polymer composition>
In a nitrogen atmosphere, the polymer composition (polymer composition 1.0 g + water 3.0 g) was left to dry for 1 hour in an oven heated to 130 ° C. From the weight change before and after drying, the solid content (%) and the volatile component (%) were calculated.

<Example 1>
A glass reactor equipped with a thermometer, a stirrer, a nitrogen inlet tube and a reflux condenser was obtained by adding phenoxypolyethylene glycol having a number average molecular weight of 974 (average 20 mol of ethylene oxide to phenol, hereinafter referred to as PH200). 149.3 parts by mass, 10.7 parts by mass of maleic acid, and 1.1 parts by mass of isopropyl alcohol were charged. The charge was dissolved by heating under a nitrogen stream, and the temperature was raised to 128 ° C. with stirring. Next, while maintaining the temperature at 128 ° C., 6.8 parts by mass of perbutyl I (containing 75% of tert-butyl peroxyisopropyl monocarbonate, manufactured by NOF Corporation, hereinafter referred to as PBI) is continuously added over 250 minutes. It was dripped. 20 minutes after the start of dropping of PBI, 53.3 parts by mass of acrylic acid was added dropwise over 240 minutes. Stirring was continued for another 55 minutes after the dropping of acrylic acid was completed to obtain a polymer.
After adding 128.3 parts by mass of ion-exchanged water to the obtained polymer, 0.9 part by mass of 35% H ₂ O ₂ (manufactured by ADEKA) is added and aged at 50 to 70 ° C. for 30 minutes. A polymer composition (1) containing the polymer of the present invention was obtained. The graft ratio of the polymer in the obtained polymer composition was 79%, and the number average molecular weight was 12000.
The monomer content of the polymer composition (1) was 96 ppm maleic acid and 50 ppm acrylic acid based on 100% by mass of the polymer composition (in terms of solid content).

<Example 2>
In Example 1, 170.9 parts by mass of PH200, 5.6 parts by mass of maleic acid, 4.6 parts by mass of PBI, 67.6 parts by mass of acrylic acid, 132.9 parts by mass of ion-exchanged water, 35% A polymer composition (2) was obtained in the same manner as in Example 1 except that 1.0 part by mass of H ₂ O ₂ was used.
The graft ratio of the polymer in the obtained polymer composition was 73%, and the molecular weight was 9300.
The content of the monomer in the polymer composition (2) was 0 ppm for maleic acid and 75 ppm for acrylic acid with respect to 100% by mass of the polymer composition (in terms of solid content).

<Example 3>
A glass reactor equipped with a thermometer, a stirrer, a nitrogen inlet tube, and a reflux condenser was obtained by adding phenoxypolyethylene glycol having a number average molecular weight of 1414 (average 30 moles of ethylene oxide to phenol, hereinafter referred to as PH300). 192.0 parts by mass, 12.8 parts by mass of maleic acid, and 1.3 parts by mass of isopropyl alcohol were charged. The charge was dissolved by heating under a nitrogen stream, and the temperature was raised to 128 ° C. with stirring. Next, while maintaining the temperature at 128 ° C., 6.8 parts by mass of PBI was continuously added dropwise over 250 minutes. 20 minutes after the start of dropping of PBI, 51.2 parts by mass of acrylic acid was dropped over 240 minutes. Stirring was continued for another 55 minutes after the dropping of acrylic acid was completed to obtain a polymer.
By adding 137.8 parts by mass of ion-exchanged water to the obtained polymer, 1.05 parts by mass of 35% H ₂ O ₂ (manufactured by ADEKA) is added and aged at 50 to 70 ° C. for 30 minutes. A polymer composition (3) containing the polymer of the present invention was obtained. The graft ratio of the polymer in the obtained polymer composition was 79%, and the number average molecular weight was 14,300.
The monomer content of the polymer composition (3) was 109 ppm maleic acid and 0 ppm acrylic acid based on 100% by mass of the polymer composition (in terms of solid content).

<Comparative Example 1>
A comparative polymer composition (1) was obtained in the same manner as in Example 2 except that the polymerization temperature in Example 2 was changed to 120 ° C.
The graft ratio of the polymer in the obtained comparative polymer composition was 68%, and the molecular weight was 10400.

<Comparative example 2>
In Example 1, 189.2 parts by mass of PH200, 0 part by mass of maleic acid, and perbutyl D (containing Di-tert-butyl peroxide 98%, manufactured by NOF Corporation, hereinafter referred to as PBD) as an initiator. Comparative weight was the same as in Example 1 except that 4.3 parts by mass, 47.3 parts by mass of acrylic acid, 237.3 parts by mass of ion-exchanged water, and 1.0 part by mass of 35% H ₂ O ₂ were used. A combined composition (2) was obtained.
The graft ratio of the polymer in the obtained comparative polymer composition was 47%, and the molecular weight was 5800.

  The polymerization results are summarized in Table 1.

From the above results, it was revealed that the polymer composition of the present invention has a better graft ratio of the polymer contained as compared with the conventional polymer composition. Therefore, it can be expected that the temporal stability of the polymer composition is good.

Claims (1)

In the presence of a polymerization initiator and a polyoxyalkylene compound,
A polymer composition comprising a polymer produced essentially by a step of polymerizing a monomer at 125 ° C. or higher and 150 ° C. or lower,
The polyoxyalkylene compound has a structure in which the main chain terminal structure is selected from an aryl group having 7 or less carbon atoms, an alkyl group having 7 or less carbon atoms, an alkenyl group having 7 or less carbon atoms, and a hydroxyl group,
The polymer has a structural unit (a) derived from a monocarboxylic acid monomer of 75 mol% or more and 99 mol% or less, based on 100 mol% of structural units derived from all monomers, a dicarboxylic acid monomer. 1 mol% or more and 25 mol% or less of the structural unit (b) derived from the monomer with respect to 100 mol% of the structural unit derived from all monomers,
The polymerization initiator is an organic peroxide having a 10-hour half-life temperature of 80 ° C. or higher and 100 ° C. or lower,
The content of the polyoxyalkylene compound with respect to 100% by mass of the polymer composition (in terms of solid content) is 1 to 30% by mass,
The polymer composition whose content of the dicarboxylic acid monomer with respect to 100% by mass of the polymer composition (in terms of solid content) is 0 to 10,000 ppm.