JP2016065344A - Pitch control agent for pulp containing ether bond-containing copolymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pitch control agent for pulp used in a paper making process for inhibiting attachment of a pitch to manufacturing devices and pulp and suppressing quality reduction of a paper product by the pitch.SOLUTION: The ether bond-containing copolymer contains a structural unit derived from an ether bond-containing monomer and a structural unit derived from (meth)acrylic acid-based monomer with a specific ration and has a specific weight average molecular weight and carbon black dispersion ability (transmission coefficient %) of 0.1 to 60%.SELECTED DRAWING: None

Description

The present invention relates to a pitch control agent for pulp that is used in a papermaking process, suppresses the adhesion of pitch to production equipment and pulp, and prevents the deterioration of the quality of paper products due to the pitch.

Conventionally, in the manufacturing process of paper and pulp, obstacles due to pitch have occurred, and various drugs have been developed in order to suppress or prevent this. This pitch is a water-insoluble adhesive substance mainly composed of organic substances derived from natural resins and gum substances released from wood, pulp and paper, as well as additives used in the manufacturing process of paper and pulp. Say.

In general, pitch is dispersed in a colloidal form in white water of the paper and pulp manufacturing process, but some external action such as large shear force, rapid pH change, sulfate band (aluminum sulfate) It is considered that the colloidal state is destroyed due to the excessive addition of, etc., and aggregates and enlarges. This cohesive and enormous pitch not only adheres to paper, pulp, fan pumps, pipes, chests, wires, felts, rolls, and other manufacturing equipment due to its adhesiveness, but also removes these deposits. And re-adheres to paper and pulp. The spots and defects of the paper formed in this way deteriorate the quality of the paper product.
Further, the generated paper breakage causes a pitch failure such as a reduction in productivity and workability. In recent years, with the diversification of paper, the types and usage of additives have increased, and as the use of water in the manufacturing process has become more closed, the occurrence of pitch disturbance has increased and the occurrence has increased. The form is complicated.

Various methods have been proposed to suppress the above-described pitch disturbance. For example, Patent Document 1 describes that deposits (pitch) are suppressed by using a chelating agent and a surfactant in combination. Patent Document 2 describes that a copolymer of acrylic acid and acryloyloxyethyltrimethylammonium chloride is used as a pitch control agent for a papermaking process.

JP 2013-28887 A JP 2003-221798 A

Although Patent Document 1 describes that a chelating agent and a surfactant may be used in combination, in order to exhibit sufficient calcium scale preventing ability with a chelating agent, an equimolar amount of chelating agent with calcium ions Therefore, there is a problem that the cost is increased.
Patent Document 2 discloses the effect of preventing the pitch failure by the acrylic acid copolymer, but does not disclose any countermeasures related to the calcium scale. The pitch control agent for pulp requires the ability to prevent calcium scale. When the calcium scale preventing ability is low, there arises a problem that the effect of preventing an inorganic-based pitch obstacle that the calcium salt is deposited and adheres to the pipe is also low.
Further, when the carbon black dispersibility is low, the colloidal dispersion that causes the pitch failure tends to aggregate. A colloidal dispersion contains a large amount of organic carbon-based material, and a material having high carbon black dispersibility as carbon-based particles is required.

This invention is made | formed in view of such a situation, and it aims at providing the pitch control agent for pulp which can manufacture a high quality pulp and / or paper efficiently.

When the present inventors examined the copolymer which can be used suitably for the pitch control agent for pulp, it originates in the structural unit derived from the ether bond containing monomer, and the (meth) acrylic acid type monomer. It has been found that an ether bond-containing copolymer containing a structural unit at a specific ratio and having a specific weight average molecular weight exhibits excellent carbon black dispersibility, and has completed the present invention.

<1>
The pulp pitch control agent of the present invention is
An ether bond-containing copolymer,
A structural unit derived from an ether bond-containing monomer;
Including a structural unit derived from a (meth) acrylic acid monomer,
The ether bond-containing copolymer is:
When the total amount of the structural unit derived from the ether bond-containing monomer and the structural unit derived from the (meth) acrylic acid monomer is 100% by mass,
For a total amount of 100 mass% of structural units derived from all monomers forming the ether bond-containing copolymer,
0.1 mass% or more and 55 mass% or less of a structural unit derived from an ether bond-containing monomer,
Containing 45 mass% or more and 99.9 mass% or less of structural units derived from (meth) acrylic acid monomers,
It is a pitch control agent for pulp containing an ether bond-containing copolymer having a weight average molecular weight of 500 to 100,000.

<2>
The pulp pitch control agent of the present invention is
An ether bond-containing copolymer,
A structural unit (a) represented by the following general formula (1) derived from the ether bond-containing monomer (A), a structural unit (b) derived from the (meth) acrylic acid monomer (B), and Including
The ether bond-containing copolymer is:
When the total amount of the structural unit (a) and the structural unit (b) is 100% by mass,
For a total amount of 100 mass% of structural units derived from all monomers forming the ether bond-containing copolymer,
The structural unit (a) is 0.1% by mass or more and 55% by mass or less,
Containing 45 mass% or more and 99.9 mass% or less of the structural unit (b),
It is a pitch control agent for pulp containing an ether bond-containing copolymer having a weight average molecular weight of 500 to 100,000.

(In the general formula (1), R ⁰ represents a hydrogen atom or a methyl group. R ¹ represents a CH ₂ group, a CH ₂ CH ₂ group or a direct bond. X represents a hydroxyl group, the following general formula (2 ) Or a group represented by the following general formula (3) Y represents a hydroxyl group, a group represented by the following general formula (2), or a group represented by the following general formula (3). Provided that one of X and Y represents a hydroxyl group, and the other represents a group represented by the following general formula (2) or a group represented by the following general formula (3). Represents.)

(In the general formulas (2) and (3), R ² is the same or different and represents an alkylene group having 2 to 4 carbon atoms. N is an average addition of an oxyalkylene group (—O—R ² —). The number of moles represents 0 to ^5. R ³ , R ⁴ and R ⁵ each independently represents an alkyl group having 1 to 20 carbon atoms.)

<3>
The said ether bond containing copolymer of this invention is a pitch control agent for pulp containing the ether bond containing copolymer whose carbon black dispersibility (permeability%) is 0.1 to 60%.

<4>
The said ether bond containing copolymer of this invention is a pitch control agent for pulp containing the ether bond containing copolymer whose calcium ion capture | acquisition ability is 100-400 mgCaCO3 / g.

The present invention is described in detail below.
In addition, even if it combines two or more each preferable form of this invention described below, it is a preferable form of this invention.

(Ether bond-containing copolymer)
First, the ether bond-containing copolymer of the present invention will be described.
The ether bond-containing copolymer (hereinafter also referred to as “polymer”) is a structural unit derived from all monomers forming the ether bond-containing copolymer (hereinafter also referred to as “all structural units”). With respect to the total amount of 100% by mass, the structural unit (a) is 0.1% by mass or more and 30% by mass or less, the structural unit (b) is 70% by mass or more and 99.9% by mass or less, and the structural unit (c 0 mass% or more and 60 mass% or less.
The structural unit (a) is derived from the ether bond-containing monomer (A), the structural unit (b) is derived from the (meth) acrylic acid monomer (B), and the structural unit (c) is sulfone. Derived from the acid group-containing monomer (C).
Furthermore, the weight average molecular weight of the said ether bond containing copolymer is 500-100,000.

<Ether bond-containing monomer>
The ether bond-containing copolymer of the present invention is a polymer essentially comprising a structural unit derived from an ether bond-containing monomer. The ether bond-containing monomer is not particularly limited as long as a carbon-carbon double bond and an ether bond exist, but can be represented by the following chemical formula.
_{^{CH 2 = C (R 0)}} -R 1 -O-CH 2 -T
(In the chemical formula, R ⁰ represents a hydrogen atom or a methyl group. R ¹ represents a CH ₂ group, a CH ₂ CH ₂ group, or a direct bond. T represents a substituent having a hydroxyl group.)
T in the chemical formula is not particularly limited as long as it is a substituent having a hydroxyl group, and a hydrocarbon group having 1 to 20 carbon atoms may be included in addition to the hydroxyl group. The bonding mode may include a single bond, a double bond, or an aromatic ring. Further, T in the chemical formula may contain an oxygen atom, a nitrogen atom or other hetero atoms in addition to the hydroxyl group and the hydrocarbon group.
A structural unit derived from an ether bond-containing monomer refers to a structure in which a double bond is opened by a polymerization reaction to form a single bond.

<Ether bond-containing monomer (A)>
The ether bond-containing copolymer of the present invention may be expressed as a polymer essentially comprising the structural unit (a) derived from the ether bond-containing monomer (A) (hereinafter also referred to as monomer (A)). it can.
The structural unit (a) derived from the ether bond-containing monomer (A) is represented by the following general formula (1). This is a form in which the carbon-carbon double bond of the ether bond-containing monomer (A) represented by the following general formula (4) is a single bond.

(In the general formula (1), R ⁰ represents a hydrogen atom or a methyl group. R ¹ represents a CH ₂ group, a CH ₂ CH ₂ group or a direct bond. X represents a hydroxyl group, the following general formula (2 ) Or a group represented by the following general formula (3) Y represents a hydroxyl group, a group represented by the following general formula (2), or a group represented by the following general formula (3). Provided that one of X and Y represents a hydroxyl group, and the other represents a group represented by the following general formula (2) or a group represented by the following general formula (3). Represents.)

(In the general formulas (2) and (3), R ² is the same or different and represents an alkylene group having 2 to 4 carbon atoms. N is an average addition of an oxyalkylene group (—O—R ² —). The number of moles represents 0 to ^5. R ³ , R ⁴ and R ⁵ each independently represents an alkyl group having 1 to 20 carbon atoms.)

Since the structural unit (a) has a hydrophobic group as in the general formula (2) or (3), it exhibits a good pitch failure prevention effect. In addition, by having such a structural unit (a), the ether bond-containing copolymer has improved dispersibility in hydrophobic particles, and also exhibits excellent chelating ability, so extremely good pitch failure prevention. The effect can be demonstrated.

The ether bond-containing monomer (A) has a polymerizable unsaturated bond (carbon-carbon double bond), ether bond, hydroxyl group, and sulfone group such as a vinyl group, a methallyl group, and a (meth) acryl group. It is the structure which has.

Furthermore, as said ether bond containing monomer (A), following General formula (4);

(In the general formula (4), R ⁰ represents a hydrogen atom or a methyl group. R ¹ represents a CH ₂ group, a CH ₂ CH ₂ group or a direct bond. X represents a hydroxyl group, and the general formula (2 ) Or a group represented by the general formula (3) Y represents a hydroxyl group, a group represented by the general formula (2), or a group represented by the general formula (3). Provided that one of X and Y represents a hydroxyl group, and the other represents a group represented by the general formula (2) or a group represented by the general formula (3). Represents.)

In the general formula (4), the ^{R 1} is a direct ^{_{bond, H 2 C = C (R}} 0 ⁾ of the general formula (4) -R 1 -O- ^{_{is, H 2 C = C (R}} 0 ) -O-. The same applies to the general formula (1).
^{_{H 2 C = C (R 0}} ) -R 1 - is, ^{R 0} is a methyl group, methallyl group when ^{R 1} is CH ₂ group; ^{R 0} is a methyl group, when ^{R 1} is _CH 2 CH ₂ group An isoprenyl group; when R ⁰ is a methyl group and R ¹ is a direct bond, an isopropenyl group; when R ⁰ is a hydrogen atom and R ¹ is a CH ₂ group, an allyl group; R ⁰ is a hydrogen atom and R ¹ is a CH ₂ In the case of CH ₂ group, a butenyl group; R ⁰ is a hydrogen atom, and R ¹ is a direct bond, it represents a vinyl group.
H ₂ C═C (R ⁰ ) —R ¹ — is preferably an isoprenyl group, a methallyl group, an allyl group, or a vinyl group. From the viewpoint of increasing the polymerizability, an isoprenyl group, a methallyl group, and an allyl group are more preferable. When the isoprenyl group and the methallyl group are used, dispersibility to hydrophobic particles is improved, and excellent chelating ability is exhibited. An extremely good pitch failure prevention effect can be exhibited.

X and Y in the general formulas (1) and (4) each independently represent a hydroxyl group, a group represented by the general formula (2), or a group represented by the general formula (3). . However, either one of X and Y represents a hydroxyl group, and the other represents a group represented by the general formula (2) or a group represented by the general formula (3).

R ² in the general formulas (2) and (3) is the same or different and represents an alkylene group having 2 to 4 carbon atoms. Examples of the alkylene group having 2 to 4 carbon atoms include an ethylene group, a propylene group, and a butylene group. From the viewpoint of improving the polymerizability of the ether bond-containing monomer (A), an alkylene group having 2 to 3 carbon atoms such as an ethylene group or a propylene group is preferred. As said alkylene group, 1 type (s) or 2 or more types can be used.
N in the general formulas (2) and (3) is an average added mole number of an oxyalkylene group (—O—R ² —), and represents a number of 0 to 5.
From the standpoint of improving dispersibility in hydrophobic particles and further exhibiting an extremely good pitch hindrance prevention effect by improving chelating ability, n is preferably 0 to 4, more preferably 0 to 3, 2 is more preferable, 0 to 1 is particularly preferable, and 0 is most preferable.

R < ³ >, R < ⁴ >, R < ⁵ > in the said General formula (2), (3) represents a C1-C20 alkyl group each independently. Examples of the alkyl group having 1 to 20 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, heptyl group, octyl group, Nonyl group, decyl group, icosyl group and the like can be mentioned. The alkyl group having 1 to 20 carbon atoms may be substituted. Examples of the substituent include an amino group and a hydroxyl group. Carbon number of a preferable alkyl group is 1-15, More preferably, it is 1-10, More preferably, it is 1-6, Most preferably, it is 1-4. From the viewpoint of improving dispersibility in hydrophobic particles, and further exhibiting an extremely good pitch hindrance prevention effect by improving chelating ability, a methyl group, an ethyl group, and a butyl group are preferable, and a butyl group is more preferable.

Moreover, R ⁴ and R ⁵ in the general formula (3) may be bonded to each other to form a cyclic structure. In this case, the cyclic structure formed by the nitrogen atom, R ⁴ and R ⁵ is a 3- to 7-membered ring, that is, the total carbon number of R ⁴ and R ⁵ is 2 to 6 in that the cyclic structure is stabilized. Preferably there is.

As the combination of X and Y, X is a hydroxyl group, Y is a group represented by the general formula (2); X is a hydroxyl group, and Y is a group represented by the general formula (3); X is the general formula The group represented by (2), Y is a hydroxyl group; X is a group represented by the general formula (3), and Y is a hydroxyl group.
From the viewpoint of improving dispersibility in hydrophobic particles and further exhibiting a very good pitch hindrance prevention effect by improving chelating ability, X is preferably a hydroxyl group and Y is represented by the general formula (2). Group: X is a hydroxyl group, Y is a group represented by the general formula (3), more preferably X is a hydroxyl group, and Y is a group represented by the general formula (2).

The ether bond-containing copolymer of the present invention has “structural unit (a) derived from ether bond-containing monomer (A)” means that the finally obtained polymer has the general formula (1). It has a structural unit represented by). That is, the “structural unit (a) derived from the ether bond-containing monomer (A)” in the present invention includes those in which the process of forming the structural unit (a) extends before and after the polymerization reaction. After synthesizing the bond-containing monomer (A), it is introduced into the polymer by copolymerizing it with other monomer components, and the main chain portion of the ether bond-containing copolymer is copolymerized. And then obtained by introducing a side chain having a specific structure.
The ether bond-containing copolymer of the present invention may have only one type of structural unit (a), or may have two or more types.

The content of the structural unit (a) is the total amount of structural units derived from all monomers forming the ether bond-containing copolymer (structural unit (a), structural units (b), (c) and (Total amount of (e)) It is 0.5 mass% or more and 55 mass% or less with respect to 100 mass%. If the content of the structural unit (a) is within the above range, when the ether bond-containing copolymer of the present invention is used as a pitch control agent for pulp, dispersibility to hydrophobic particles is improved, and excellent Since the chelating ability is exhibited, it is possible to exhibit a very good pitch failure prevention effect.
The content of the structural unit (a) is preferably 1% by mass or more and 25% by mass or less, more preferably 2% by mass or more and 20% by mass or less, and further preferably 3% by mass or more and 15% by mass. %, Particularly preferably 4% by mass or more and 12% by mass or less.

It does not restrict | limit especially as a preparation method of the said ether bond containing monomer (A), It can prepare by arbitrary appropriate methods. As such a preparation method, for example, the epoxy group of a compound having a carbon-carbon double bond and an epoxy ring is bonded to the hydroxyl group and / or the compound having a C 1-4 alkyl group and a hydroxyl group and / or an amino group. Or the method of manufacturing by reacting an amino group etc. is mentioned as a simple method. Examples of the compound having a carbon-carbon double bond and an epoxy ring include (meth) allyl glycidyl ether and glycidyl vinyl ether. Examples of the compound having an alkyl group having 1 to 4 carbon atoms and a hydroxyl group and / or an amino group include methanol, ethanol, isopropanol, n-butanol, di-n-isopropylamine, and di-n-butylamine. The reaction may be performed without a catalyst, but may be performed in the presence of an acidic catalyst such as boron trifluoride or a basic catalyst such as sodium hydroxide or potassium hydroxide.

<(Meth) acrylic acid monomer>
The ether bond-containing copolymer of the present invention is a polymer essentially comprising a structural unit derived from a (meth) acrylic acid monomer.
The acrylic acid monomer can be represented by the following chemical formula.
CH ₂ = C (R ⁷ ) COOR ⁶
(In the chemical formula, R ⁶ represents a hydrogen atom, a metal atom, an ammonium group, or an organic amine group.
R ⁷ represents a hydrogen atom or a methyl group. )
The structural unit derived from a (meth) acrylic acid monomer indicates a structure in which a double bond is opened by a polymerization reaction to form a single bond.

<(Meth) acrylic acid monomer (B)>
The ether bond-containing copolymer of the present invention includes a polymer that also contains a structural unit (b) derived from a (meth) acrylic acid monomer (B) (hereinafter also referred to as monomer (B)). It can also be expressed.
As the (meth) acrylic acid monomer (B) in the present invention, the following general formula (5);

(Wherein R ⁶ represents a hydrogen atom, a metal atom, an ammonium group or an organic amine group, and R ⁷ represents a hydrogen atom or a methyl group).
The structural unit (b) derived from the (meth) acrylic acid monomer (B) is a form in which the carbon-carbon double bond of the monomer (B) is a single bond. General formula (6);

(Wherein R ⁶ and R ⁷ are the same as defined above).
By having such a structural unit (b), the ether bond-containing copolymer has improved dispersibility in hydrophobic particles and also exhibits excellent chelating ability, and therefore has an extremely good pitch hindrance prevention effect. It can be demonstrated.

In the general formulas (5) and (6), when R ⁶ is a metal atom, an ammonium group or an organic amine group, the (meth) acrylic acid monomer (B) is a metal salt of (meth) acrylic acid. It becomes an ammonium salt or an organic amine salt.
Examples of the metal atom in R ⁶ of the general formulas (5) and (6) include alkali metal atoms such as lithium, sodium and potassium; alkaline earth metal atoms such as magnesium and calcium; aluminum and iron and the like. .
Examples of the organic amine group in R ⁶ include alkanolamines such as monoethanolamine, diethanolamine and triethanolamine; alkylamines such as monoethylamine, diethylamine and triethylamine; polyamines such as ethylenediamine and triethylenediamine.
R ⁶ is preferably a hydrogen atom, an alkali metal, or an ammonium group because the dispersibility of the resulting ether bond-containing copolymer in hydrophobic particles and chelating ability are improved, and a hydrogen atom, sodium, potassium, or ammonium group is preferred. More preferred are a hydrogen atom and sodium.
In the general formulas (5) and (6), R ⁷ is a hydrogen atom or a methyl group. In the case of a hydrogen atom, it becomes acrylic acid, and in the case of a methyl group, it becomes methacrylic acid.
Specific examples of the (meth) acrylic acid monomer (B) include acrylic acid and its salt, methacrylic acid and its salt, and preferably acrylic acid and its sodium salt.

The ether bond-containing copolymer of the present invention has the “structural unit (b) derived from the (meth) acrylic acid monomer (B)”. It means having a structural unit represented by Formula (6). That is, the “structural unit (b) derived from the (meth) acrylic acid monomer (B)” in the present invention includes those in which the step of forming the structural unit (b) extends before and after the polymerization reaction. After the synthesis of the (meth) acrylic acid monomer (B), it is introduced into the polymer by copolymerizing it with other monomer components, or an ether bond-containing copolymer. Those obtained by forming a main chain portion by copolymerization and then introducing a side chain having a specific structure are also included.
The ether bond-containing copolymer of the present invention may have only one type of structural unit (b), or may have two or more types.

The content of the structural unit (b) is the total amount of structural units derived from all monomers forming the ether bond-containing copolymer (the structural units (a) and (b) and the structural unit (c) described later). (Total amount of (e)) It is 45 mass% or more and 99.5 mass% or less with respect to 100 mass%. If the content of the structural unit (b) is within the above range, when the ether bond-containing copolymer of the present invention is used as a pitch control agent for pulp, dispersibility into hydrophobic particles is improved, and excellent Since the chelating ability is exhibited, it is possible to exhibit a very good pitch failure prevention effect.
The content of the structural unit (b) is preferably 45% by mass or more and 98.5% by mass or less, more preferably 53% by mass or more and 97.5% by mass or less, and further preferably 59% by mass. As mentioned above, it is 96.3 mass% or less, Most preferably, it is 63 mass% or more and 95.2 mass% or less.

In the present invention, when calculating the mass ratio (% by mass) of the structural unit (b) to the total amount of structural units derived from all monomers forming the ether bond-containing copolymer, the corresponding acid It shall be calculated by conversion. For example, the mass proportion of the structural unit —CH ₂ —CH (COONa) — derived from sodium acrylate is the mass proportion (mass of the structural unit —CH ₂ —CH (COOH) — derived from acrylic acid, which is the corresponding acid. %). Similarly, when calculating the mass ratio (mass%) of the (meth) acrylic acid monomer (B) with respect to the total amount of all monomers, it is calculated in terms of the corresponding acid. For example, the mass proportion of sodium (meth) acrylate is calculated as the mass proportion (mass%) of (meth) acrylic acid which is the corresponding acid.
The method for preparing the (meth) acrylic acid monomer (B) is not particularly limited.

<Sulphonic acid group-containing monomer (C)>
The ether bond-containing copolymer of the present invention is a polymer in which a structural unit (c) derived from a sulfonic acid group-containing monomer (C) (hereinafter also referred to as monomer (C)) is essential.

Examples of the structural unit (c) include a structure in which the carbon-carbon double bond of the monomer (C) (at least one when there are a plurality of monomers) is a single bond. The monomer (C) is preferably represented by the following general formula (7), and the structural unit (c) is preferably represented by the following general formula (8). It is.

(In the formula, R ⁷ represents a hydrogen atom or a methyl group. R ⁸ represents a CH ₂ group, a CH ₂ CH ₂ group or a direct bond. R ⁹ and R ¹⁰ each independently represent a hydroxyl group or — SO ₃ Z is represented, and Z represents a hydrogen atom, a metal atom, an ammonium group, or an organic amine group, provided that at least one of R ⁹ and R ¹⁰ represents —SO ₃ Z.)

(Wherein R ⁷ , R ⁸ , R ⁹ and R ¹⁰ are the same as described above).
By having such a structural unit (c), the ether bond-containing copolymer has improved dispersibility in hydrophobic particles, and also exhibits excellent chelating ability, and therefore has an extremely good pitch hindrance prevention effect. It becomes possible to demonstrate.

In the general formulas (7) and (8), R ⁷ represents a hydrogen atom or a methyl group, preferably a hydrogen atom.
R ⁸ represents a CH ₂ group, a CH ₂ CH ₂ group or a direct bond, and is preferably a CH ₂ group.
R ⁹ and R ¹⁰ each independently represent a hydroxyl group or —SO ₃ Z, and at least one of R ⁹ and R ¹⁰ represents —SO ₃ Z. In order to exhibit the effect of the present invention more sufficiently, it is preferable that only one of R ⁹ and R ¹⁰ is —SO ₃ Z.
Z represents a hydrogen atom, a metal atom, an ammonium group or an organic amine group.
When Z is a metal atom, an ammonium group, or an organic amine group, —SO ₃ Z represents a metal salt, ammonium salt, or organic amine salt of sulfonic acid.
Examples of the metal atom and organic amine group in Z include the same as the metal atom and organic amine group in R ⁶ described above. Z is preferably a hydrogen atom, an alkali metal atom, or an ammonium group, more preferably a hydrogen atom, sodium, or potassium, and still more preferably a hydrogen atom or sodium.

Note that the ether bond-containing copolymer of the present invention has “structural unit (c) derived from sulfonic acid group-containing monomer (C)” means that the finally obtained polymer has the general formula ( It means having a structural unit represented by 8). That is, the “structural unit (c) derived from the sulfonic acid group-containing monomer (C)” in the present invention includes those in which the step of forming the structural unit (c) extends before and after the polymerization reaction. After synthesizing the sulfonic acid group-containing monomer (C), it is introduced into the polymer by copolymerizing it with other monomer components, or the main chain portion of the ether bond-containing copolymer. Those obtained by copolymerization and then introduced by introducing side chains having a specific structure are also included.
The ether bond-containing copolymer of the present invention may have only one type of structural unit (c), or may have two or more types.

The content of the structural unit (c) is the total amount of structural units derived from all monomers forming the ether bond-containing copolymer (structural units (a), (b), (c) and structural units described later). The total amount of (e) is 0 to 60% by mass with respect to 100% by mass. If the content of the structural unit (c) is within the above range, when the ether bond-containing copolymer of the present invention is used as a pitch control agent for pulp, dispersibility to hydrophobic particles is improved, and excellent Since the chelating ability is exhibited, it is possible to exhibit a very good pitch failure prevention effect.
Even if the content of the structural unit (c) is 0% by mass, it becomes an ether bond-containing copolymer useful as a pitch control agent for pulp. However, when the structural unit (c) is used, the content is preferably 0. 0.5% by mass or more and 30% by mass or less, more preferably 0.5% by mass or more and 27% by mass or less, still more preferably 0.7% by mass or more and 26% by mass or less, and particularly preferably. It is 0.8 mass% or more and 25 mass% or less.

In the present invention, when calculating the mass ratio (% by mass) of the structural unit (c) to the total amount of structural units derived from all monomers forming the ether bond-containing copolymer, the corresponding acid It shall be calculated by conversion. For example, the mass proportion of the structural unit derived from sodium 3-allyloxy-2-hydroxypropanesulfonate is the mass proportion (mass%) of the structural unit derived from 3-allyloxy-2-hydroxypropanesulfonic acid which is the corresponding acid. Calculate as Similarly, also when calculating the mass ratio (mass%) of the sulfonic acid group-containing monomer (C) with respect to the total amount of all monomers, it is calculated in terms of the corresponding acid. For example, the mass proportion of sodium 3-allyloxy-2-hydroxypropanesulfonate is calculated as the mass proportion (mass%) of 3-allyloxy-2-hydroxypropanesulfonic acid, which is the corresponding acid.

Moreover, as said sulfonic acid group containing monomer (C), the compound containing a polymerizable unsaturated bond (carbon-carbon double bond) and a sulfonic acid (salt) group is mentioned. Specifically, vinyl sulfonic acid and its salt, styrene sulfonic acid and its salt, (meth) allyl sulfonic acid and its salt, 3- (meth) allyloxy-2-hydroxypropane sulfonic acid and its salt, 3- (meta ) Allyloxy-1-hydroxypropanesulfonic acid and its salt, 2- (meth) allyloxyethylenesulfonic acid and its salt, 2-acrylamido-2-methylpropanesulfonic acid and its salt, and the like. In order to more fully exhibit the effects of the present invention, preferably, 3- (meth) allyloxy-2-hydroxypropanesulfonic acid and a salt thereof, more preferably 3-allyloxy-2-hydroxypropanesulfonic acid and Its sodium salt.

It does not restrict | limit especially as a preparation method of the said sulfonic acid group containing monomer (C), It can prepare by arbitrary appropriate methods. As such a preparation method, for example, a method of adding bisulfite to the glycidyl group of (meth) allyl glycidyl ether can be mentioned as a simple method.

<Other monomers>
The ether bond-containing copolymer of the present invention comprises other monomers (E) (the ether bond-containing monomer (A), the sulfonic acid group-containing monomer (C), and a (meth) acrylic acid monomer. You may have the structural unit (e) derived from monomers other than a body (B). The ether bond-containing copolymer may have only one type of structural unit (e), or may have two or more types.

The other monomer (E) (hereinafter also referred to as monomer (E)) is not particularly limited as long as it is copolymerizable with the monomers (A), (C) and (B). Instead, it can be appropriately selected depending on the desired effect.
Specific examples of the other monomer (E) include carboxyls other than the monomer (B) such as methacrylic acid, maleic acid, crotonic acid, itaconic acid, 2-methyleneglutaric acid and salts thereof. Group-containing monomer; monomer obtained by adding alkylene oxide to unsaturated alcohol such as (meth) allyl alcohol and isoprenol; polyalkylene glycol chain-containing monomer such as (meth) acrylic acid ester of alkoxyalkylene glycol; vinyl Vinyl aromatic monomers having a heterocyclic aromatic hydrocarbon group such as pyridine and vinyl imidazole; Dialkylaminoalkyl (meth) acrylates such as dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate and dimethylaminopropyl acrylate, dimethylamino Ethylacrylamide, Amino group-containing monomers such as dialkylaminoalkyl (meth) acrylamides such as methylaminoethyl methacrylamide and dimethylaminopropyl acrylamide, diallylamine such as diallylamine and diallylamine, and quaternized products thereof; N-vinyl monomers such as vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, N-vinyl-N-methylformamide, N-vinyl-N-methylacetamide, N-vinyloxazolidone; (meth) acrylamide, N Amide monomers such as N, dimethylacrylamide and N-isopropylacrylamide; hydroxyl group-containing monomers such as (meth) allyl alcohol and isoprenol; butyl (meth) acrylate and 2-ethylhexyl (meth) acryl (Meth) acrylic acid alkyl ester monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4 -Hydroxyalkyl (meth) acrylate monomers such as hydroxybutyl (meth) acrylate and 2-hydroxyhexyl (meth) acrylate; vinylaryl monomers such as styrene, indene and vinylaniline; isobutylene and vinyl acetate Can be mentioned.
The quaternized product is obtained by reacting a quaternizing agent usually used for the amino group-containing monomer. Examples of the quaternizing agent include alkyl halides and dialkyl sulfuric acid.

The structural unit (e) derived from the other monomer (E) refers to a polymerizable unsaturated bond (carbon-carbon double bond) (multiple units of the other monomer (E)). Is a structural unit in which at least one is replaced by a single bond. The ether bond-containing copolymer of the present invention has "structural unit (e) derived from other monomer (E)" means that the finally obtained polymer is the monomer (E). It means having a structural unit in which an unsaturated double bond is replaced with a single bond.
The content of the structural unit (e) derived from the other monomer (E), which is an optional component, is the total amount of structural units derived from all the monomers forming the ether bond-containing copolymer (that is, the structure). The total amount of the units (a), (b), (c) and (e)) is preferably 0 to 34% by mass with respect to 100% by mass. More preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%, Most preferably, it is 0 mass%.

In the case where the structural unit (e) is a structural unit derived from an amino group-containing monomer, the mass ratio relative to the total amount of structural units derived from all monomers, When calculating the mass ratio with respect to the total amount of monomers, it shall be calculated as the mass ratio of the corresponding unneutralized amine. For example, when the other monomer (E) is vinylamine hydrochloride, the mass ratio (% by mass) of vinylamine which is the corresponding unneutralized amine is calculated.
In addition, when calculating the mass ratio (mass%) of a monomer containing a quaternized amino group or a structural unit derived therefrom, the mass of the counter anion is not taken into account (not including) Shall.
When the structural unit (e) is a structural unit derived from an acid group-containing monomer, the mass ratio (mass%) to the total amount of structural units derived from all monomers is calculated in terms of the corresponding acid. And Moreover, when calculating the mass ratio (mass%) with respect to the total amount of all the monomers of an acid group containing monomer, it shall calculate by corresponding acid conversion.

<Physical properties of ether bond-containing copolymer>
In the ether bond-containing copolymer of the present invention, the structural units (a), (b), (c) and, if necessary, the structural units (e) are introduced at a specific ratio as described above. Each structural unit may exist in either a block shape or a random shape.

The composition ratio of the structural units derived from the respective monomers constituting the ether bond-containing copolymer of the present invention is 100% by mass in the total amount of structural units derived from all monomers forming the ether bond-containing copolymer. On the other hand, when the structural unit (a) is 0.1 to 55% by mass, the structural unit (b) is 45 to 99.9% by mass, and the structural unit (c) is 0 to 60% by mass, Since the dispersibility is improved and excellent chelating ability is exhibited, it is possible to exhibit a very good pitch obstruction preventing effect.
On the other hand, when the content of the structural unit (a) is less than the above range, the dispersibility in the hydrophobic particles may be lowered, and further, the pitch hindrance prevention effect may be lowered due to a decrease in chelating ability.
The copolymer which does not contain a structural unit (c) may be sufficient. In this case, an excellent pitch failure prevention effect is exhibited by adjusting the contents of the structural unit (a) and the structural unit (b). In the case of a copolymer containing the structural unit (c), when the content of the structural unit (c) is small, the pitch hindrance prevention effect may be lowered. In addition, when the content of the structural unit (b) is less than 45% by mass, the effect of preventing pitch failure may be deteriorated.
As a composition ratio of the structural unit derived from each monomer constituting the ether bond-containing copolymer of the present invention, the structural unit (a) is preferably 1 to 25% by mass and the structural unit (b) is 45 to 45%. 98.5 mass%, structural unit (c) is 0.5-30 mass%, more preferably, structural unit (a) is 2-20 mass%, and structural unit (b) is 53-97.5 mass%. %, The structural unit (c) is 0.5 to 27% by mass, more preferably the structural unit (a) is 3 to 15% by mass, the structural unit (b) is 59 to 96.3% by mass, and the structural unit. (C) is 0.7 to 26% by mass, and particularly preferably, the structural unit (a) is 4 to 12% by mass, the structural unit (b) is 63 to 95.2% by mass, and the structural unit (c) is 0.8 to 25% by mass.
In addition, the structural unit (e) is included at a ratio of 0 to 34% by mass with respect to 100% by mass of the total amount of all monomers (structural units (a), (b), (c), and (e)). May be. More preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%, Most preferably, it is 0 mass%.

When the ether bond-containing copolymer of the present invention does not contain the structural unit (c), the structural unit (a) is 1 to 99% by mass and the structural unit (b) is 1 to 99% by mass. In addition, the dispersibility to hydrophobic particles is improved and the excellent chelating ability is exhibited, so that it is possible to exhibit a very good pitch obstruction preventing effect.
On the other hand, when the content of the structural unit (a) is less than the above range, the dispersibility in the hydrophobic particles may be lowered, and further, the pitch hindrance prevention effect may be lowered due to a decrease in chelating ability.
Moreover, when content of a structural unit (b) is less than the above-mentioned range, the dispersibility to a hydrophobic particle falls, and also the pitch obstruction prevention effect may fall by the fall of chelate ability.
As composition ratio of each monomer used for superposition | polymerization, Preferably, structural unit (a) is 1-50 mass%, and a structural unit (b) is 50-99 mass%, More preferably, a structural unit ( a) is 2 to 30% by mass, structural unit (b) is 70 to 98% by mass, more preferably 3 to 20% by mass of structural unit (a) and 80 to 97% by mass of structural unit (b). Particularly preferably, the structural unit (a) is 4 to 15% by mass and the structural unit (b) is 85 to 96% by mass.
Moreover, the structural unit (e) may be included in a proportion of 0 to 34% by mass with respect to 100% by mass of the total amount of all monomers (structural units (a), (b) and (e)). More preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%, Most preferably, it is 0 mass%.

Furthermore, the weight average molecular weight of the said ether bond containing copolymer is 500-100,000. When the weight average molecular weight is within the above range, when used as a pitch control agent for pulp of the present invention, the dispersibility to hydrophobic particles is improved and an excellent chelating ability is exhibited, so that an extremely good pitch is obtained. It is possible to exert an effect of preventing failure.
The weight average molecular weight is preferably 1,000 to 90,000, more preferably 2,000 to 80,000, still more preferably 3,000 to 70,000, particularly preferably 5,000 to 70,000, most preferably Preferably it is 7,000-65,000.
In addition, in this specification, a weight average molecular weight is a measured value by GPC (gel permeation chromatography), and can be measured with the apparatus and measurement conditions described in the Example mentioned later.

The ether bond-containing copolymer of the present invention has a carbon black dispersibility (permeability%) of 0.1 to 60% for the ether bond-containing copolymer to exhibit an excellent pitch hindrance prevention effect. There is a need. When the carbon black dispersibility is good, the colloidal dispersion that causes the pitch hindrance becomes difficult to aggregate. The colloidal dispersion contains a large amount of an organic carbon-based material, and an ether bond-containing copolymer having a high carbon black dispersibility, which is a carbon-based particle, has a good pitch hindrance prevention effect.
It is preferable that the carbon black dispersibility (transmittance%) of the ether bond-containing copolymer is in the above-described range since an excellent pitch hindrance prevention effect can be exhibited.
The carbon black dispersibility (permeability%) is more preferably 0.5 to 55%, more preferably 1 to 50%, particularly preferably 2 to 48%, and most preferably 3 to 46%.
If the carbon black dispersibility (transmittance%) is larger than the above range, the pitch hindrance prevention effect is lowered, which is not preferable.
In addition, carbon black dispersibility (transmittance%) can be measured by the method as described in the Example mentioned later.

The ether bond-containing copolymer and composition thereof of the present invention have a high calcium ion scavenging ability, but in the papermaking process, a large amount of water is used, so that the calcium ion scavenging ability contained in water is high. High is preferred. Since the calcium ion scavenging ability is high, the effect of preventing an inorganic-based pitch obstacle that the calcium salt is deposited and adheres to the pipe is improved.
The calcium ion capturing ability is preferably 100 to 400 mg CaCO ₃ / g. More preferably 150~350mgCaCO ₃ / g, more preferably 180~300mgCaCO ₃ / g, particularly preferably 250~280mgCaCO ₃ / g.
In addition, calcium ion capture | acquisition ability can be measured by the method as described in the Example mentioned later.

[Method for producing ether bond-containing copolymer]
The ether bond-containing copolymer of the present invention includes an ether bond-containing monomer (A) represented by the general formula (4) and an acrylic acid monomer (B) represented by the general formula (5). The sulfonic acid group-containing monomer (C) represented by the general formula (7) is essential, and if necessary, the monomer component containing the other monomer (E) is added at a predetermined ratio. It can be produced by copolymerization.

In the method for producing an ether bond-containing copolymer of the present invention, the composition ratio of each monomer used for polymerization is the total monomer (monomer (A), (B), (C), (E). ) To 100% by mass, the monomer (A) is 0.1 to 55% by mass, the monomer (B) is 45 to 99.9% by mass, and the monomer (C) is 0 to 60%. When the content is% by mass, the dispersibility in hydrophobic particles is improved, and further, the improvement of chelating ability makes it possible to exhibit a very good pitch failure prevention effect.
On the other hand, when the content of the monomer (A) is less than the above range,
The dispersibility to hydrophobic particles is lowered, and further, the effect of preventing pitch disturbance may be lowered due to a decrease in chelating ability.
The copolymer which does not contain a monomer (C) may be sufficient. In this case, an excellent pitch failure prevention effect is exhibited by adjusting the contents of the monomer (A) and the monomer (B). In the case of a copolymer containing the monomer (C), when the content of the monomer (C) is small, the pitch hindrance prevention effect may be lowered. Moreover, when content of a monomer (B) becomes less than the above-mentioned range, a pitch obstruction prevention effect may fall.

The composition ratio of each monomer used for the polymerization is preferably 1 to 25% by mass of monomer (A), 45 to 98.5% by mass of monomer (B), and monomer (C ) Is 0.5 to 30% by mass, more preferably 2 to 20% by mass of monomer (A), 53 to 97.5% by mass of monomer (B), and monomer (C). Is 0.5 to 27% by mass, more preferably 3 to 15% by mass of monomer (A), 59 to 96.3% by mass of monomer (B), and monomer (C). It is 0.7-26 mass%, Most preferably, the monomer (A) is 4-12 mass%, the monomer (B) is 63-95.2 mass%, and the monomer (C) is 0. .8-25% by mass.

Moreover, monomer (E) is a ratio of 0-34 mass% with respect to 100 mass% of total amounts of all monomers (monomer (A), (B), (C), (E)). May be included. More preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%, Most preferably, it is 0 mass%.

Moreover, in the manufacturing method of the ether bond containing copolymer of this invention, when a monomer (C) is not included, a monomer (A) is 1-99 mass%, a monomer (B) is 1- 1 When the content is 99% by mass, the dispersibility in hydrophobic particles is improved, and further, the improvement of chelating ability makes it possible to exhibit a very good pitch failure prevention effect.
On the other hand, when the content of the monomer (A) is less than the above range, the dispersibility to the hydrophobic particles is lowered, and further, the pitch hindrance prevention effect may be lowered due to the lowered chelating ability.
Moreover, when content of a monomer (B) becomes less than the above-mentioned range, a pitch obstruction prevention effect may fall. As a composition ratio of each monomer used for polymerization,
Preferably, the monomer (A) is 1 to 50% by mass, the monomer (B) is 50 to 99% by mass,
More preferably, the monomer (A) is 2 to 30% by mass, the monomer (B) is 70 to 98% by mass, and more preferably, the monomer (A) is 3 to 20% by mass and the structure. The unit (b) is 80 to 97% by mass, and particularly preferably the monomer (A) is 4 to 15% by mass and the monomer (B) is 85 to 96% by mass.

Moreover, the monomer (E) may be included in a proportion of 0 to 34% by mass with respect to 100% by mass of the total amount of all monomers (monomers (A), (B) and (E)). Good. More preferably, it is 0-10 mass%, More preferably, it is 0-5 mass%, Most preferably, it is 0 mass%.

The polymerization method for obtaining the ether bond-containing copolymer of the present invention is not particularly limited, and a commonly used polymerization method or a modified method thereof can be employed. Examples of the polymerization method include a radical polymerization method, specifically, an oil-in-water emulsion polymerization method, a water-in-oil emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, a precipitation polymerization method, and a solution polymerization method. An aqueous solution polymerization method, a bulk polymerization method, or the like can be employed. Among the exemplified polymerization methods, it is preferable to employ a solution polymerization method in terms of high safety and reduction in production cost (polymerization cost).

In the solution polymerization method, the monomer component is polymerized in a solvent.
Although it is possible to use only an organic solvent as the solvent, it is preferable to include water. More preferably, water is used in an amount of 50% by mass or more, more preferably 80% by mass or more, and particularly preferably 100% by mass of water with respect to 100% by mass of the total solvent. Examples of the organic solvent that can be used alone or with water include lower alcohols such as ethanol and isopropanol; amides such as N, N-dimethylformamide; ethers such as diethyl ether and dioxane; glycol, glycerin, and polyethylene glycol Preferred examples include aqueous organic solvents such as
As for the said solvent, only 1 type may be used and 2 or more types may be used together.

The amount of the solvent used is preferably 40 to 300 parts by mass, more preferably 100 parts by mass based on the total amount of all monomers (monomers (A), (B), (C) and (E)). Is 45 to 200 parts by mass, more preferably 50 to 150 parts by mass. When the amount of the solvent used is less than 40 parts by mass relative to 100 parts by mass of the total amount of all monomers, the molecular weight of the resulting polymer may be too high. On the other hand, when the amount of the solvent used exceeds 300 parts by mass with respect to 100 parts by mass of the total amount of all monomers, the concentration of the resulting polymer is lowered, and in some cases, the solvent may need to be removed. .
The solvent may be partly or wholly charged in the reaction vessel in the initial stage of polymerization, but a part of the solvent may be added (dropped) into the reaction system during the polymerization reaction, or the monomer. Components, polymerization initiators, and the like may be added (dropped) into the reaction system during the polymerization reaction together with these components in a form that has been previously dissolved in a solvent.

The reaction form of the solution polymerization method is not particularly limited, and the reaction can be carried out in a form usually used. Typically, for example, in the solvent charged in advance in the reaction system, the single monomer is used. The form which reacts by dripping a body and a polymerization initiator (henceforth "initiator"), etc. are mentioned. In such a reaction mode, the concentration of each solution to be dropped is not particularly limited, and any appropriate concentration can be adopted.
As a form which reacts by dripping the said monomer and an initiator in the solvent previously prepared in the said reaction system, a monomer (A), a monomer (B), a single quantity, for example The polymer (C), the monomer (E) as necessary, the initiator component, and other additives as necessary are dissolved in the solvent, or without being dissolved in the solvent, during polymerization. A mode in which polymerization is carried out by appropriately adding (dropping) to the reaction system. Moreover, in the said reaction form, a part or all of the total usage-amount of a monomer (A) can also be previously added (initial preparation) in a reaction system before superposition | polymerization start.

<Polymerization initiator>
As the polymerization initiator used in the production method, those usually used can be used. Specifically, hydrogen peroxide; persulfates such as sodium persulfate, potassium persulfate and ammonium persulfate; 2,2′-azobis (2-amidinopropane) hydrochloride, 4,4′-azobis-4-cyanovalerin Azo compounds such as acid, azobisisobutyronitrile, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile); benzoyl peroxide, lauroyl peroxide, peracetic acid, di-t-butyl Preferable examples include organic peroxides such as peroxide and cumene hydroperoxide. Of these polymerization initiators, hydrogen peroxide, persulfate, and 2,2′-azobis (2-amidinopropane) hydrochloride are preferred, and persulfate and 2,2′-azobis (2-amidinopropane) hydrochloric acid. A salt is more preferred. These polymerization initiators may be used alone or in combination of two or more.

<Chain transfer agent>
In the production method, it is preferable to use a chain transfer agent as the molecular weight regulator of the polymer. When a chain transfer agent is used, it is possible to inhibit the polymer to be produced from becoming too high in molecular weight and to efficiently produce a low molecular weight ether bond-containing copolymer.
In the production method, it is preferable to use a compound capable of generating bisulfite and / or bisulfite as the chain transfer agent. In that case, it is more preferable to use a polymerization initiator in addition to the bisulfite and the compound capable of generating bisulfite. Furthermore, you may use a heavy metal ion together as a reaction accelerator mentioned later.
When a compound capable of generating bisulfite and / or bisulfite is used as a chain transfer agent, a polymer having a sulfonic acid (salt) group at at least one of the ends of the main chain can be obtained.

Examples of the compound capable of generating the bisulfite include pyrosulfite (salt), dithionite (salt), sulfurous acid (salt), and the like, and pyrosulfurous acid (salt) is preferable.
As the salt, a salt with a metal atom, ammonium or an organic amine is preferable.
Examples of the metal atom include a monovalent metal atom of an alkali metal such as lithium, sodium, and potassium; a divalent metal atom of an alkaline earth metal such as calcium and magnesium; and a trivalent metal atom such as aluminum and iron. Etc.
Examples of the organic amine include alkanolamines such as monoethanolamine, diethanolamine and triethanolamine; triethylamine and the like.
Among the above-mentioned compounds capable of generating bisulfite and bisulfite, bisulfite is preferable.
Preferred examples of the bisulfite include sodium bisulfite, potassium bisulfite, and ammonium bisulfite, and sodium bisulfite is more preferred.
Preferred examples of the compound capable of generating bisulfite include sodium pyrosulfite, potassium pyrosulfite; sodium dithionite, potassium dithionite; sodium sulfite, potassium sulfite, ammonium sulfite; and the like. Sodium pyrosulfite Is more preferable.
The bisulfite and the compound capable of generating bisulfite may be used alone or in combination of two or more.

Further, as the chain transfer agent, in addition to the above-mentioned bisulfite and the compound capable of generating bisulfite, the following can also be used. Examples of the chain transfer agent include thiol chain transfers such as mercaptoethanol, thioglycolic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, octyl 3-mercaptopropionic acid, 2-mercaptoethanesulfonic acid, and n-dodecyl mercaptan. Agents; Halides such as carbon tetrachloride, methylene chloride, bromoform, bromotrichloroethane; secondary alcohols such as isopropanol and glycerin; phosphorous acid, hypophosphorous acid and salts thereof (sodium hypophosphite, hypophosphorous acid) Lower oxides such as potassium) and salts thereof; and the like. The chain transfer agent can be used alone or in combination of two or more.

<Reaction accelerator>
In the production method, a reaction accelerator may be added for the purpose of reducing the use amount of a polymerization initiator or the like. Examples of the reaction accelerator include heavy metal ions.

In the production method, in the polymerization, in addition to the above-described compounds, a decomposition catalyst for the polymerization initiator or a reducing compound may be added to the reaction system.

<Amount of polymerization initiator used>
The total use amount of the polymerization initiator is not particularly limited as long as it is an amount capable of initiating copolymerization of monomers, but all monomer components (monomer (A), (B), (C) and ( It is preferable that it is 15 g or less with respect to 1 mol of total amounts of E)).

The addition amount of the chain transfer agent is not limited as long as the monomers (A), (B), (C) and (E) are polymerized satisfactorily, but the monomers (A), (B), Preferably it is 1-20g with respect to 1 mol of total amounts of all the monomer components which consist of (C) and (E), More preferably, it is 2-15g. If it is less than 1 g, the molecular weight may not be controlled. On the other hand, if it exceeds 20 g, a large amount of impurities may be produced, and the pure polymer content may be reduced. In particular, when bisulfite is used, if the amount added exceeds 20 g, surplus bisulfite may be decomposed in the reaction system and sulfurous acid gas may be generated, which is also economically disadvantageous. There is a fear.
On the other hand, it is preferable for the amount of chain transfer agent added to be in the above-mentioned range, since it is possible to suppress the production of 3SPA as a by-product, and an extremely good pitch hindrance prevention effect can be exhibited.

As a combination of the initiator and the chain transfer agent, it is preferable to use one or more persulfates and bisulfites.
In this case, the mixing ratio of persulfate and bisulfite is not particularly limited, but it is preferable to use 0.5 to 5 parts by mass of bisulfite with respect to 1 part by mass of persulfate.

The total amount of the chain transfer agent, the initiator and the reaction accelerator used is 1 mol of the total amount of all monomer components consisting of the monomers (A), (B), (C) and (E). It is preferable that it is 2-20g. By setting it as such a range, the ether bond containing copolymer of this invention can be produced efficiently, and the molecular weight distribution of the said polymer can be made into a desired thing.

In the production method, as the method for adding the monomer component, the polymerization initiator and the chain transfer agent to the reaction vessel, a continuous charging method such as dropping or divided charging can be applied. In addition, each may be introduced alone into the reaction vessel, or may be mixed in advance with other components, a solvent, or the like.

<Polymerization conditions>
In the production method, the polymerization temperature is appropriately determined depending on the polymerization method used, the solvent, the polymerization initiator, and the like, but is preferably 25 to 200 ° C.

The pressure at the time of polymerization in the production method is not particularly limited, and any appropriate pressure can be adopted. For example, it may be under normal pressure (atmospheric pressure), reduced pressure, or increased pressure.

(Ether bond-containing copolymer composition)
The ether bond-containing copolymer composition of the present invention includes the ether bond-containing copolymer.
Further, the ether bond-containing copolymer composition of the present invention may contain other components in addition to the ether bond-containing copolymer and the bisulfite addition compound.
Although it does not specifically limit as said other component, For example, a polymerization initiator residue, a residual monomer, the by-product at the time of superposition | polymerization, a water | moisture content, etc. are mentioned, These 1 type (s) or 2 or more types can be contained.
The ether bond-containing copolymer composition of the present invention comprises 3-sulfopropion, which is a compound having a structure in which a bisulfite is added to the ether bond-containing copolymer and the (meth) acrylic acid monomer (B). Acid (3SPA), and the content of the compound (3SPA) is 0.01% by mass or more and 1.5% by mass with respect to 100% by mass of the solid content of the ether bond-containing copolymer composition. % Or less is preferable.
When the content of the bisulfite addition compound is within the above range, the pitch hindrance prevention effect is improved. Further, the content is preferably 0.02% by mass or more and 1.0% by mass or less, more preferably 0.03% by mass or more and 0.8% by mass or less.

A compound having a structure in which bisulfite is added to the (meth) acrylic acid monomer (B) (hereinafter also referred to as “bisulfite addition compound”) is used as a chain transfer agent, and the above-mentioned bisulfite and / or Using a compound capable of generating bisulfite, and the bisulfite added to the (meth) acrylic acid monomer (B), the monomer (B) did not polymerize and remained impurities. It is. Specific examples include 3-sulfopropionic acid (salt).

The ether bond-containing copolymer composition of the present invention is an ether bond-containing copolymer that has an effect of preventing pitch damage from 1 to 100 mass% of the total amount of the ether bond-containing copolymer composition. It is preferable to contain 99.99 mass%. More preferably, it is 30-99 mass%, More preferably, it is 40-98 mass%.
One of the preferred forms of the ether bond-containing copolymer composition is a form containing 40 to 60% by mass of the ether bond-containing copolymer and 38.5 to 59.99% by mass of water.

[Use of ether bond-containing copolymer and composition thereof]
The ether bond-containing copolymer of the present invention and the composition thereof can exhibit high performance in aqueous applications, and are used as a pitch control agent for pulp for producing high-quality pulp and / or paper with high production efficiency. In addition, it is possible to exhibit a more excellent pitch failure prevention effect.

The ether bond-containing copolymer of the present invention and the composition thereof have excellent dispersibility in hydrophobic particles (carbon black dispersibility) and high calcium ion scavenging ability, and thus exhibit excellent pitch damage prevention effects. can do. Therefore, the ether bond-containing copolymer of the present invention and the composition thereof can be suitably used as a pitch control agent for pulp.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.
The quantification of monomers and reaction intermediates and the measurement of various physical properties were performed by the following methods.

<Measurement conditions of weight average molecular weight (GPC)>
Apparatus: L-7000 series manufactured by Hitachi, Ltd. Detector: HITACHI RI Detector L-7490
Column: SHODEX Asahipak GF-310-HQ, GF-710-HQ, GF-1G 7B manufactured by Showa Denko Co., Ltd.
Column temperature: 40 ° C
Flow rate: 0.5 ml / min
Calibration curve: Polyacrylic acid standard made by Sowa Chemical Co., Ltd.
Eluent: 0.1N sodium acetate / acetonitrile = 3/1 (mass ratio).

<Quantification of ether bond-containing monomer, acrylic acid-based monomer, sulfonic acid group-containing monomer, bisulfite addition compound>
Quantification of the ether bond-containing monomer, acrylic acid monomer, sulfonic acid group-containing monomer, and bisulfite addition compound was performed using liquid chromatography under the following conditions.
Measuring device: L-7000 series detector manufactured by Hitachi, Ltd .: UV detector L-7400 manufactured by Hitachi, Ltd.
Column: SHODEX RSpak DE-413 manufactured by Showa Denko Co., Ltd.
Temperature: 40.0 ° C
Eluent: 0.1% phosphoric acid aqueous solution Flow rate: 1.0 ml / min.

<Measurement of 3-sulfonepropionic acid (3SPA) concentration>
Apparatus: Waters gradient HPLC system Column: TSK-GEL ODS-100V 5 μm 4.6 × 250 mm 2 in series Eluent: 0.02 M potassium dihydrogen phosphate (adjusted to pH 2.5)
Flow rate: 0.7 mL / min
Temperature: 30 ° C
Detector: UV detector (210 nm)

<Measurement of carbon black dispersibility>
In the measurement of carbon black dispersibility, first, a buffer solution and a 0.1% polymer aqueous solution were prepared. The buffer solution was 6.76 g of glycine, 5.26 g of sodium chloride and 0.50 g of 48% sodium hydroxide to make pure water to 60.0 g, then calcium chloride dihydrate 0.123 g, chloride 0.056 g of magnesium hexahydrate was added, and pure water was added to make 1000.0 g. The 0.1% polymer aqueous solution used was prepared by diluting a polymer with an appropriate amount of water to a solid content concentration of 0.1% by mass.

Next, each solution and carbon black powder were charged into a 30 ml test tube in a predetermined order and in a predetermined amount. The predetermined order and the predetermined amount are as follows: 0.03 g of carbon black powder is charged as the first, 27.0 g of buffer solution is charged as the second, and finally 0.1% polymer aqueous solution 3 is charged. 0.0 g was charged.

After each solution and carbon black powder were charged in this order, the test tube was capped and slowly reversed up and down 60 times to stir the contents. Thereafter, the mixture was allowed to stand at room temperature for 20 hours. After 20 hours, the supernatant was immediately put into a 1 cm quartz cell, and the transmittance at a UV wavelength of 380 nm was measured. In addition, the one where the transmittance | permeability has shown has shown that the carbon black powder is disperse | distributing well, and its performance is excellent.

<Measurement of calcium ion scavenging ability>
In a beaker having a capacity of 100 cc, 50 g of 0.001 mol / L calcium chloride aqueous solution was collected, and 10 mg of the copolymer was added in terms of solid content. Next, the pH of this aqueous solution was adjusted to 9-11 with dilute sodium hydroxide. Then, 1 ml of 4 mol / L potassium chloride aqueous solution was added as a calcium ion electrode stabilizer under stirring. Using a titration device (Hiranuma AUTO TITRATOR COM-1700) and a calcium ion composite electrode (ORIION 9720BNWP), free calcium ions are measured, and how many mg of calcium ions are captured per 1 g of copolymer in terms of calcium carbonate. Was calculated by calculation. The unit of calcium ion capturing ability is “mgCaCO ₃ / g”.

[Example 1]
(1) Synthesis of monomer In a 500 mL glass four-necked flask equipped with a reflux condenser and a stirrer (paddle blade), 370.0 g of n-butyl alcohol and 4.27 g of pelleted sodium hydroxide were added. The temperature was raised to 60 ° C. while charging and stirring. Next, 57.0 g of allyl glycidyl ether (hereinafter also referred to as “AGE”) was added over 30 minutes, and then reacted for 5 hours. This solution was transferred to a 1,000 ml eggplant flask and desolvated with a rotary evaporator. To this, 200.0 g of a 20% by mass aqueous sodium chloride solution was added, this aqueous solution was transferred to a 500 ml separatory funnel, shaken well, and then allowed to stand until the layers were separated, and the lower layer was removed. The remaining upper layer was transferred to a 300 ml eggplant flask and desolvated with a rotary evaporator. The precipitated salt was removed by filtration to obtain monomer (1).

(2) A 1,000 mL glass separable flask equipped with a polymerization reflux condenser and a stirrer (paddle blade) was charged with 128.4 g of pure water and 0.0187 g of Mole salt, and the temperature was raised to 85 ° C. while stirring. Thus, a polymerization reaction system was obtained. Next, 270.0 g of 80% aqueous acrylic acid solution (hereinafter also referred to as “80% AA”), sodium 3-allyloxy-2-hydroxypropanesulfonate in a polymerization reaction system maintained at 85 ° C. with stirring. 40% aqueous solution (hereinafter also referred to as “40% HAPS”) 192.0 g, monomer (1) 15.0 g, 15% sodium persulfate aqueous solution (hereinafter also referred to as “15% NaPS”) 100 g, And 40 g of 35% sodium bisulfite aqueous solution (hereinafter also referred to as “35% SBS”) was dropped from separate nozzles. The dropping time of each solution is 180 minutes for 80% AA, 120 minutes for 40% HAPS, 120 minutes for monomer (1), 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. did. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 85 ° C. (ripening) for another 30 minutes to complete the polymerization. After completion of the polymerization, 193.3 g of a 48% aqueous sodium hydroxide solution (hereinafter also referred to as “48% NaOH”) was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, a polymer aqueous solution (1) having a solid content concentration of 45% containing the polymer (1) of the present invention was obtained. The weight average molecular weight of the polymer (1) was 8,200. The residual acrylic acid was 80 ppm, the residual HAPS was 850 ppm, and the residual 3 SPA was 0.21%. The results are shown in Table 1.

[Example 2]
A glass-separable flask with a capacity of 1,000 mL equipped with a reflux condenser and a stirrer (paddle blade) was charged with 128.4 g of pure water and 0.0187 g of Mole salt, and the temperature was raised to 85 ° C. while stirring to polymerize the reaction. It was a system. Next, in a polymerization reaction system maintained at 85 ° C. with stirring, 80% AA 270.0 g, 40% HAPS 192.0 g, monomer (1) 15.0 g, 15% NaPS 80 g, and 35 30 g of% SBS was dropped from each separate nozzle. The dropping time of each solution is 180 minutes for 80% AA, 120 minutes for 40% HAPS, 120 minutes for monomer (1), 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. did. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 85 ° C. (ripening) for another 30 minutes to complete the polymerization. After completion of the polymerization, 193.3 g of a 48% aqueous sodium hydroxide solution (hereinafter also referred to as “48% NaOH”) was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
Thus, a polymer aqueous solution (2) having a solid content concentration of 45% containing the polymer (2) of the present invention was obtained. The weight average molecular weight of the polymer (2) was 17,000. The residual acrylic acid was 120 ppm, the residual HAPS was 1,050 ppm, and the residual 3 SPA was 0.16%. The results are shown in Table 1.

[Example 3]
A glass separable flask with a capacity of 1,000 mL equipped with a reflux condenser and a stirrer (paddle blade) was charged with 146.8 g of pure water and 0.0186 g of Mole salt, and heated to 85 ° C. while stirring. A polymerization reaction system was used. Next, in a polymerization reaction system maintained at 85 ° C. with stirring, 270.0 g of 80% AA, 11 g of monomer (1), 60 g of 15% NaPS, and 20 g of 35% SBS were respectively provided in separate nozzles. More dripped. The dropping time of each solution was 180 minutes for 80% AA, 140 minutes for monomer (1), 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 85 ° C. (ripening) for another 30 minutes to complete the polymerization. After completion of the polymerization, 197.5 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
In this way, a polymer aqueous solution (3) having a solid content concentration of 45% containing the polymer (3) of the present invention was obtained. The weight average molecular weight of the polymer (3) was 35,000. Further, the residual acrylic acid was 72 ppm, and the residual 3 SPA was 0.13%. The results are shown in Table 1.

[Example 4]
A glass separable flask with a capacity of 1,000 mL equipped with a reflux condenser and a stirrer (paddle blade) was charged with 146.8 g of pure water and 0.0186 g of Mole salt, and heated to 85 ° C. while stirring. A polymerization reaction system was used. Next, 270.0 g of 80% AA, 24 g of monomer (1), 80 g of 15% NaPS, and 30 g of 35% SBS were separately added to a separate nozzle in a polymerization reaction system maintained at 85 ° C. with stirring. More dripped. The dropping time of each solution was 180 minutes for 80% AA, 140 minutes for monomer (1), 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 85 ° C. (ripening) for another 30 minutes to complete the polymerization. After completion of the polymerization, 197.5 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
In this way, a polymer aqueous solution (4) having a solid content concentration of 45% containing the polymer (4) of the present invention was obtained. The weight average molecular weight of the polymer (4) was 60,000. Further, the residual acrylic acid was 60 ppm, and the residual 3 SPA was 0.18%. The results are shown in Table 1.

[Example 5]
A glass-separable flask with a capacity of 1,000 mL equipped with a reflux condenser and a stirrer (paddle blade) was charged with 128.4 g of pure water and 0.0187 g of Mole salt, and the temperature was raised to 85 ° C. while stirring to polymerize the reaction. It was a system. Next, in a polymerization reaction system maintained at 85 ° C. with stirring, 80% AA 270.0 g, 40% HAPS 6.0 g, monomer (1) 24.0 g, 15% NaPS 80 g, and 35 35 g of% SBS was dropped from each separate nozzle. The dropping time of each solution is 180 minutes for 80% AA, 120 minutes for 40% HAPS, 120 minutes for monomer (1), 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. did. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 85 ° C. (ripening) for another 30 minutes to complete the polymerization. After completion of the polymerization, 193.3 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
In this way, a polymer aqueous solution (5) having a solid content concentration of 45% containing the polymer (5) of the present invention was obtained. The weight average molecular weight of the polymer (5) was 10,000. The residual acrylic acid was 90 ppm, and the residual HAPS was 250 ppm. The results are shown in Table 1.

[Example 6]
A glass-separable flask with a capacity of 1,000 mL equipped with a reflux condenser and a stirrer (paddle blade) was charged with 128.4 g of pure water and 0.0187 g of Mole salt, and the temperature was raised to 85 ° C. while stirring to polymerize the reaction. It was a system. Next, in a polymerization reaction system maintained at 85 ° C. with stirring, 800.0% AA 270.0 g, 40% HAPS 144.0 g, monomer (1) 14.4 g, 15% NaPS 80 g, and 35 35 g of% SBS was dropped from each separate nozzle. The dropping time of each solution is 180 minutes for 80% AA, 120 minutes for 40% HAPS, 120 minutes for monomer (1), 190 minutes for 15% NaPS, and 175 minutes for 35% SBS. did. Moreover, the dropping rate of each solution was made constant, and each solution was dropped continuously.
After the completion of the dropwise addition of 80% AA, the reaction solution was kept at 85 ° C. (ripening) for another 30 minutes to complete the polymerization. After completion of the polymerization, 193.3 g of 48% NaOH was gradually added dropwise while stirring and allowing the polymerization reaction liquid to cool, thereby neutralizing the polymerization reaction liquid.
In this way, a polymer aqueous solution (6) having a solid content concentration of 45% containing the polymer (6) of the present invention was obtained. The weight average molecular weight of the polymer (6) was 10,000. The residual acrylic acid was 150 ppm, and the residual HAPS was 1,250 ppm. The results are shown in Table 1.

[Comparative Example 1]
A 45% aqueous solution of sodium polyacrylate having a weight average molecular weight of 5,000 was used as a comparative polymer (1). The results are shown in Table 1.

[Comparative Example 2]
A 40% aqueous solution of acrylic acid / maleic acid = 30/70 (weight ratio) having a weight average molecular weight of 60,000 was used as a comparative polymer (2). The results are shown in Table 1.

[Comparative Example 3]
A 40% aqueous solution of sodium polyacrylate having a weight average molecular weight of 50,000 was used as a comparative polymer (3). The results are shown in Table 1.

From the results of the Examples and Comparative Examples, the structural unit (a) derived from the ether bond-containing monomer (A) and the structural unit (b) derived from the (meth) acrylic acid monomer (B) , The ether unit-containing copolymer of the present invention having a specific weight average molecular weight, and the structural unit (c) derived from the sulfonic acid group-containing monomer (C), and the polymer. The ether bond-containing copolymer composition of the present invention containing a specific amount of a compound having a structure in which bisulfite is added to the (meth) acrylic acid monomer (B) is used as a pitch control agent for pulp as hydrophobic particles. It has been found that since the dispersibility into (the carbon black dispersibility) is high and the calcium ion scavenging ability is high, it is possible to exert an excellent pitch failure prevention effect.

In addition, as a pitch control agent for pulp, it is an essential requirement that the dispersibility in hydrophobic particles (carbon black dispersibility) is high. Comparative Examples 1 to 3 show excellent values of calcium ion capturing ability, but the dispersibility into hydrophobic particles (carbon black dispersibility) is inferior to the ether bond-containing copolymer of the present invention. It is clear.

Thus, it is considered that all the mechanisms of action that sufficiently exhibit the excellent pitch failure prevention effect by using the polymer and composition having the specific configuration of the present invention are the same.
Therefore, it can be said from the results of the above-described embodiments that the present invention can be applied in the entire technical scope of the present invention and in various forms disclosed in this specification, and can exhibit advantageous effects.

Claims (3)

An ether bond-containing copolymer,
A structural unit derived from an ether bond-containing monomer;
Including a structural unit derived from a (meth) acrylic acid monomer,
The ether bond-containing copolymer is:
When the total amount of the structural unit derived from the ether bond-containing monomer and the structural unit derived from the (meth) acrylic acid monomer is 100% by mass,
For a total amount of 100 mass% of structural units derived from all monomers forming the ether bond-containing copolymer,
0.1 mass% or more and 55 mass% or less of a structural unit derived from an ether bond-containing monomer,
Containing 45 mass% or more and 99.9 mass% or less of structural units derived from (meth) acrylic acid monomers,
A pitch control agent for pulp comprising an ether bond-containing copolymer having a weight average molecular weight of 500 to 100,000. The pitch control agent for pulp containing an ether bond-containing copolymer according to claim 1, wherein the carbon black dispersibility (permeability%) is 0.1 to 60%. The pitch control agent for pulp containing an ether bond-containing copolymer according to claim 2, wherein the calcium ion scavenging ability is 100 to 400 mg CaCO ₃ / g.