JP7196725B2 - Method for producing papermaking additive - Google Patents

Description

The present invention relates to a method for producing a papermaking additive.

Polyamide polyamine-epihalohydrin resin, which is a papermaking additive, is used as a "wet paper strength agent" that does not break even when the paper gets wet with water, when making tissue paper, towel paper, and the like. Generally, a polyamidepolyamine-epihalohydrin resin is obtained by reacting an aqueous solution containing a polyamidepolyamine with epihalohydrin. However, 1,3-dihalo-2-propanol (also referred to as dihalohydrin), 3-halo -1,2-Propanediol (also called monohalohydrin) is produced, which is environmentally unfavorable and its reduction is desired.

As a production method for reducing these, for example, after reacting polyamide polyamine with a specific amount of epihalohydrin at 10 to 45° C., the reaction concentration is lowered and the reaction is performed at a temperature of 25 to 70° C. until it has a specific viscosity. (Patent Document 1), and after reacting polyamide polyamine and epihalohydrin at 20 to 40°C, a basic substance, then acid and water are added and reacted at 55 to 75°C (Patent Document 2). ing. However, in the above method, the reduction of dihalohydrin and monohalohydrin is insufficient, or even if these can be reduced, the wet paper strength effect is poor.

JP-A-02-170825 JP-A-06-001842

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a papermaking additive that can obtain a papermaking additive that maintains the wet strength effect of paper and that can reduce the content of dihalohydrin and monohalohydrin.

As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by including a specific monoalcohol in the polyamidopolyamine solution before adding the epihalohydrin, and have completed the present invention. . That is, the present invention relates to the following method for producing a papermaking additive.

1. Epihalohydrin (C) is added to a mixture of a saturated aliphatic monoalcohol (A), an aliphatic dibasic acid and/or derivative thereof (b1), and a polyamidepolyamine (B) which is a condensate of an alkylenepolyamine (b2). and then cross-linking to obtain a reaction product (D), wherein the mixture contains 5 to 70 parts by weight of component (A) with respect to 100 parts by weight of component (B). A method for manufacturing an additive.

2. 2. The method for producing a papermaking additive according to the preceding item 1, wherein the component (A) is a saturated aliphatic monoalcohol having an alkyl group of 1 to 4 carbon atoms.

3. The use ratio of component (B) and component (C) is (epoxy equivalent of component (C))/(secondary amine equivalent of component (B)) = 0.8 to 2.0, or 3. A method for producing the papermaking additive according to 2.

4. 4. The method for producing a papermaking additive according to any one of the preceding items 1 to 3, wherein the addition reaction is performed at a temperature of 5 to 40°C and the cross-linking reaction is performed at a temperature of 40 to 80°C.

5. 5. The method for producing a papermaking additive according to any one of the preceding items 1 to 4, wherein the aqueous solution of component (D) having a solid content of 25% by weight has a viscosity of 10 to 500 mPa·s at a temperature of 25°C.

According to the method for producing a papermaking additive of the present invention, the content of environmentally unpreferable dihalohydrins and monohalohydrins (hereinafter collectively referred to as "halohydrins") can be reduced, and the resulting papermaking additive can be The wet paper strength effect is also maintained when paper is made using

The method for producing the papermaking additive of the present invention comprises a saturated aliphatic monoalcohol (A) (hereinafter referred to as component (A)) and a specific polyamidepolyamine (B) (hereinafter referred to as component (B)). Epihalohydrin (C) (hereinafter referred to as component (C)) is added to the mixed solution of (1) to cause an addition reaction, followed by a cross-linking reaction to obtain a reaction product (D) (hereinafter referred to as component (D)). It includes steps.

Component (A) is a component that suppresses the formation of halohydrins during the reaction of components (B) and (C) and reduces the halohydrin content in the resulting papermaking additive.

Component (A) is not particularly limited as long as it is a saturated aliphatic monoalcohol, and various known ones can be used. Examples include linear saturated aliphatic monoalcohols such as methanol, ethanol, n-propanol and n-butanol; branched saturated aliphatic monoalcohols such as isopropanol, isobutanol, s-butanol and t-butanol. These may be used alone or in combination of two or more. Among them, aliphatic monoalcohols having an alkyl group having 1 to 4 carbon atoms are preferred, and aliphatic monoalcohols having an alkyl group having 1 to 3 carbon atoms are preferred from the viewpoint of being soluble in water and making it difficult to generate halohydrin during the reaction. , that is, methanol, ethanol, n-propanol and isopropanol are more preferable.

The content of component (A) is usually 5 to 70 parts by weight per 100 parts by weight of component (B). If the content is less than 5 parts by weight, a large amount of halohydrin is produced during the reaction, and the halohydrin content in the papermaking additive increases. On the other hand, if the content exceeds 70 parts by weight, the wet paper strength effect of the paper tends to decrease. From the same point of view, it is preferably 10 to 65 parts by weight.

Moreover, you may use a polyol together. Polyols are not particularly limited, and examples include aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol and tripropylene glycol; ethane-1,1,2-triol, glycerin, 1, Aliphatic triols such as 2,3-butanetriol and 1,2,4-butanetriol; aliphatic tetraols such as erythritol; These may be used alone or in combination of two or more. The content of polyol is not particularly limited, but is preferably 5 parts by weight or less per 100 parts by weight of component (B).

The component (B) is a polyamide polyamine, and includes an aliphatic dibasic acid and/or derivative thereof (b1) (hereinafter referred to as the (b1) component) and an alkylenepolyamine (b2) (hereinafter referred to as the (b2) component. ) is a condensate.

Component (b1) is not particularly limited, and examples include saturated aliphatic dibasic acids such as malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid and sebacic acid; itaconic acid and citraconic acid. and unsaturated aliphatic dibasic acids such as Derivatives include, for example, anhydrides of the above-mentioned aliphatic dicarboxylic acids, esters with saturated aliphatic alcohols such as methanol and ethanol, and the like. These may be used alone or in combination of two or more. Among them, saturated aliphatic dibasic acids are preferred, and adipic acid and sebacic acid are more preferred.

Component (b2) is not particularly limited, but preferably has at least two primary amino groups. Examples of such component (b2) include ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, 1,5-pentanediamine (pentamethylenediamine), 1,6 -monoalkylenediamines such as hexanediamine (hexamethylenediamine); dialkylenetriamines (diethylenetriamine, dipropylenetriamine, dibutylenetriamine, etc.), trialkylenetetramines (triethylenetetramine, tripropylenetetramine, etc.), tris(2-aminoalkyl ) amines (tris(2-aminoethyl)amine, tris(2-aminopropyl)amine, etc.), tetraalkylenepentamines (tetraethylenepentamine, tetrapropylenepentamine, etc.), polyalkylenepolyamines such as pentaethylenehexamine. be done. These may be used alone or in combination of two or more. Among them, dialkylenetriamine is preferable, and diethylenetriamine and dipropylenetriamine are more preferable.

The molar ratio of component (b1) and component (b2) used is not particularly limited, and is usually (b2)/(b1) = about 0.8 to 1.5, preferably 0.9 to 1.2. degree.

The condensation reaction with components (b1) and (b2) is not particularly limited, but usually in the presence or absence of a catalyst such as sulfuric acid, benzenesulfonic acid, p-toluenesulfonic acid, etc., at a reaction temperature of 110 to The reaction is carried out at about 250° C. for about 2 to 24 hours. The obtained condensate is preferably diluted with water or an organic solvent. The solid content concentration after dilution is about 20 to 80% by weight.

Water is not particularly limited, and examples thereof include pure water, ion-exchanged water, tap water, industrial water, and the like. These may be used alone or in combination of two or more.

The organic solvent is not particularly limited, and examples thereof include alcohols such as methanol, ethanol and isopropanol; ketones such as acetone and methyl ethyl ketone; dimethyl sulfoxide, hexane and toluene. Among them, methanol, ethanol, and isopropanol are preferable from the viewpoint of facilitating dissolution of the component (B).

The physical properties of the component (B) obtained in this way are not particularly limited, but in addition to promoting the addition reaction and cross-linking reaction between the component (B) and the component (C), gelation due to thickening is suppressed. Therefore, for example, the viscosity of an aqueous solution having a solid content of 50% by weight at a temperature of 25° C. is preferably about 200 to 1000 mPa·s. The viscosity is a value measured with a Brookfield viscometer (Brookfield viscometer) (the same shall apply hereinafter).

Component (C) is not particularly limited, and examples thereof include epichlorohydrin, epibromohydrin, and the like.

The amount of component (C) used is not particularly limited, but it suppresses the production of halohydrin during production, and maintains the wet paper strength effect when paper is made using the obtained additive for papermaking. From this point of view, the ratio of component (B) and component (C) used is preferably (epoxy equivalent of component (C))/(secondary amine equivalent of component (B)) = about 0.8 to 2.0. , is more preferably 0.9 to 1.6, and more preferably about 0.9 to 1.3.

In the method for producing a papermaking additive of the present invention, the component (C) is added to the mixed solution of the component (A) and the component (B) to cause an addition reaction in order to make it difficult to generate halohydrins during the reaction. and then cross-linking reaction to obtain component (D). A detailed description will be given below.

In the method for producing the papermaking additive of the present invention, first, a mixture of components (A) and (B) is prepared. The method for preparing the mixed solution is not particularly limited. For example, after charging the components (A) and (B), they are mixed with a stirrer or the like. ) component is added. The mixed solution may consist of only the components (A) and (B), but is preferably a mixed solution with water added. Examples of water include those mentioned above. When water is added, the total solid concentration of components (A) and (B) can be adjusted to about 20 to 80% by weight from the viewpoint of reactivity between components (B) and (C). Preferably, it is more preferably about 30 to 70% by weight.

Conditions for preparing the mixture are not particularly limited, but room temperature or below is preferable, for example. The mixing time is not particularly limited as long as the components (A) and (B) are mixed until uniform.

Next, the component (C) is added to the mixture. The addition reaction method is not particularly limited, but it is preferable to drop the component (C) from the viewpoint of controlling the heat of reaction and suppressing thickening and gelling of the papermaking additive. The dropping time is preferably 0.5 to 5 hours from the same point as above.

The conditions for the addition reaction are not particularly limited, but the temperature is preferably about 5 to 40° C., for example, from the viewpoint of preferentially proceeding the reaction. Also, the reaction time is preferably about 0.5 to 24 hours, more preferably about 2 to 24 hours. Incidentally, the reaction temperature may be appropriately set by heating or cooling. Also, the concentration of the reaction solution in the addition reaction is not particularly limited, but is preferably about 30 to 70% by weight.

Next, the liquid after the addition reaction is subjected to a cross-linking reaction to obtain the component (D). In the present invention, water is preferably added after completion of the addition reaction in order to control the viscosity of component (D) to be produced. Examples of water include those mentioned above. When water is added, it is preferable to adjust the concentration of the reaction solution to about 20 to 40% by weight.

The conditions for the cross-linking reaction are not particularly limited. is preferably about 40 to 80°C, more preferably about 40 to 70°C. Also, the reaction time is preferably about 2 to 10 hours, more preferably about 2 to 6 hours. The reaction time may be managed by measuring the viscosity of the reaction solution with a Brookfield viscometer.

In addition, in the method for producing a papermaking additive of the present invention, component (A) is used when preparing a mixed solution with component (B), and in addition to being used during or during dropping of component (C). Immediately after, at the time of addition reaction or crosslinking reaction, component (A) may be added as appropriate.

Moreover, in the said crosslinking reaction, you may add an amine in the middle.

The amine is not particularly limited, and examples thereof include primary alkanolamine such as monoethanolamine and monoisopropanolamine; diethanolamine, diisopropanolamine, di-2-hydroxybutylamine, N-methylethanolamine, N-ethylethanolamine. , N-benzylethanolamine and the like; tertiary alkanolamine such as triethanolamine and tripropanolamine; primary saturated aliphatic amines such as methylamine, ethylamine and n-propylamine; dimethylamine secondary saturated aliphatic amines such as , diethylamine and di-n-propylamine; and tertiary saturated aliphatic amines such as trimethylamine, triethylamine and tri-n-propylamine. These may be used alone or in combination of two or more. The amount of amine to be used is not particularly limited, but is preferably 10 parts by weight or less in terms of solid content per 100 parts by weight of component (B).

In the method for producing the papermaking additive of the present invention, after obtaining the component (D), the aforementioned amine, pH adjuster, water, etc. may be added. These can be added after the cross-linking reaction is complete, while cooling, or after cooling.

The pH adjuster is not particularly limited, and examples include inorganic acids such as sulfuric acid, nitric acid and phosphoric acid; organic acids such as formic acid and acetic acid; inorganic bases such as sodium hydroxide and potassium hydroxide; methylamine, ethylamine and diethylamine. , an organic base such as triethylamine; and an aqueous ammonia solution. These may be used alone or in combination of two or more. Although the pH is not particularly limited, it is preferably about 2.5 to 4 from the viewpoint of suppressing thickening of the papermaking additive during standing.

Furthermore, various known additives such as antifoaming agents, antioxidants, preservatives and chelating agents may be added to the obtained component (D).

Although the physical properties of component (D) are not particularly limited, for example, the solid content concentration is usually about 5 to 40% by weight, preferably about 10 to 30% by weight.

Further, the viscosity of the aqueous solution of component (D) having a solid content of 25% by weight at a temperature of 25° C. is usually about 10 to 500 mPa·s from the viewpoint of storage stability.

The papermaking additive of the present invention is obtained by the above-described manufacturing method, and the solution containing the component (D) can be used as it is or after being further diluted with water or the like. Moreover, the papermaking additive of the present invention is suitable as a wet paper strength agent.

The physical properties of the papermaking additive of the present invention are not particularly limited, but the halohydrin content is preferably 0.7% by weight or less. The halohydrin content in the present invention is a value measured by gas chromatography (GC).

In the present invention, the reason why the content of halohydrin is reduced when component (A) is used to prepare a mixed solution with component (B) is that the solvation effect reduces component (A) to (C) It surrounds the halogen groups in the component or the halide ions liberated during the addition reaction with the components (B) and (C), and as a result, the unreacted component (C) is prevented from reacting with the halide ions. It is considered to be for

The papermaking additive of the present invention is used by being added to various known pulp slurries prepared in the process of papermaking. The pulp slurry is not particularly limited, and for example, chemical pulp such as hardwood pulp (L-BKP) and softwood pulp (N-BKP); ) and other mechanical pulps; waste paper pulps such as corrugated waste paper. These may be used alone or in combination of two or more.

The addition amount of the papermaking additive is not particularly limited, and is usually about 0.05 to 1% by weight based on the solid weight of the pulp slurry. By setting it as the said range, the wet paper strength effect which was excellent in paper is exhibited.

The pulp slurry may optionally contain water-soluble aluminum compounds such as aluminum sulfate and polyaluminum chloride; Polymer sizing agents obtained by polymerizing saturated monomers; polyacrylamide paper strength agents, starches, pH adjusters such as sulfuric acid and sodium hydroxide, retention agents, fillers such as talc, clay, kaolin, titanium dioxide, and calcium carbonate. You may add.

EXAMPLES The present invention will be described below with reference to Examples, but the present invention is not limited to these. "%" in each example is based on weight.

(viscosity)
Using a Brookfield viscometer (manufactured by Toki Sangyo Co., Ltd.), the viscosity of the sample adjusted to 25° C. was measured.

(Halohydrin content in papermaking additive (component (D)))
The papermaking additive (component (D)) was measured by gas chromatography (product name: "HP6890/5973", manufactured by Agilent).

For dichlorohydrin and monohydrin, the area values were determined for each of the following retention times (RT) and summed up.
・Dichlorohydrin (DCH): peak around RT = 23.5 minutes ・Monochlorohydrin (MCH): peak around RT = 10.8 minutes

Production Example 1 (Production of Polyamide Polyamine (B-1))
A flask equipped with a thermometer, a condenser, a stirrer and a nitrogen inlet tube was charged with 730 g (5 mol) of adipic acid and 619 g (6 mol) of diethylenetriamine, and the temperature was raised to 120 to 120 while removing the generated water out of the system. After reacting at 200° C. for 5 hours, 1200 g of water was gradually added to obtain polyamide polyamine (B-1) having a solid concentration of 50%. The viscosity of the component (B-1) is shown in Table 1 (same below).

Production Examples 2-5
Polyamide polyamines (B-2) to (B-5) were obtained by synthesizing the compositions shown in Table 1 in the same manner as in Production Example 1.

The abbreviations in Table 1 mean the following compounds.
・AA: adipic acid ・SA: sebacic acid ・DETA: diethylenetriamine ・DPTA: dipropylenetriamine

Example 1
19 g of methanol, 400 g of component (B-1) and 91 g of deionized water were charged into an apparatus equipped with a thermometer, a cooler and a stirrer, and the liquid temperature was adjusted to 15° C. while stirring. After 110 g of epichlorohydrin (equivalence ratio (epoxy equivalent of epichlorohydrin)/(secondary amino group equivalent of component (B-1))=1.2) was added dropwise over 120 minutes, the temperature was raised to 32°C. The temperature was raised and the addition reaction was carried out for 5 hours. After adding 475 g of water, the mixture was heated to 60° C. and crosslinked for 3 hours. Next, 155 g of water and 20 g of concentrated sulfuric acid (solid concentration: 62.5%) were added and cooled to obtain component (D-1) having a solid concentration of 25% and a pH of 2.7. The physical properties of the obtained component (D-1) are shown in Table 2 (the same applies hereinafter).

Examples 2-12, Comparative Examples 3-6
The components shown in Table 2 were used in the same manner as in Example 1 to obtain components (D-2) to (D-12) and (E-3) to (E-6) having a pH of 2.7.

Comparative example 1
400 g of component (B-1) and 110 g of ion-exchanged water were charged into the same reactor as in Example 1 and stirred at 20°C. After 110 g of epichlorohydrin (equivalent ratio (epoxy equivalent of epichlorohydrin)/(secondary amino group equivalent of component (B-1))=1.2) was added dropwise at 15° C. over 90 minutes, After the temperature was raised to 30° C. and the addition reaction was carried out for 2.5 hours, 19 g of methanol was added and the addition reaction was further carried out for 2.5 hours. Then, after adding 456 g of water, the mixture was heated to 60° C. and crosslinked for 3 hours. Next, 155 g of water and 20 g of concentrated sulfuric acid (solid content concentration: 62.5%) are added and cooled, and the (E-1) component with a solid content concentration of 25%, a viscosity of 220 mPa s (25 ° C.), and a pH of 2.7 is added. Obtained.

Comparative example 2
400 g of component (B-1) and 110 g of ion-exchanged water were charged into the same reactor as in Example 1 and stirred at 20°C. After 110 g of epichlorohydrin (equivalent ratio (epoxy equivalent of epichlorohydrin)/(secondary amino group equivalent of component (B-1))=1.2) was added dropwise at 15° C. over 90 minutes, The temperature was raised to 30° C. and the addition reaction was carried out for 5 hours. After adding 19 g of methanol and 456 g of water, the mixture was heated to 60° C. and crosslinked for 3 hours. Next, 155 g of water and 20 g of concentrated sulfuric acid (solid content concentration: 62.5%) are added and cooled, and the (E-2) component with a solid content concentration of 25%, a viscosity of 210 mPa s (25 ° C.), and a pH of 2.7 is added. Obtained.

<Papermaking evaluation>
By solid content weight, a pulp slurry with a solid content concentration of 2% by weight of N-BKP / L-BKP = 50/50 is beaten, adjusted to Canadian Standard Freeness (CSF) 600 ml, and tap water was added to prepare a solid content concentration of 1% by weight. To this pulp slurry, 0.3% of each papermaking additive is added to the solid content weight of the pulp slurry, and a paper machine (Tappi Standard Sheet Machine (round type)) is used according to JIS P 8122. Paper was made so that the amount was 20 g/m ² . The papermaking pH at this time was 7.0. Then, the obtained wet paper was dehydrated by a roll press at 0.5 kg/cm ² . It was then dried in a tumble dryer at 110° C. for 2 minutes. The obtained paper was conditioned at a temperature of 20° C. and a humidity of 50% for 24 hours, and then the wet paper strength (wet breaking length) was measured according to JIS P 8135. Table 2 shows the results.

*1 The parts by weight of component (A) are indicated by the value per 100 parts by weight of the solid content of component (B).
*2 ECH means epichlorohydrin.
*3 (C)/(B) is the value of (epoxy equivalent of component (C))/(secondary amine equivalent of component (B)).

Claims (5)

Epihalohydrin (C) is added to a mixture of a saturated aliphatic monoalcohol (A), an aliphatic dibasic acid and/or derivative thereof (b1), and a polyamidepolyamine (B) which is a condensate of an alkylenepolyamine (b2). and then cross-linking to obtain a reaction product (D), wherein the mixture contains 5 to 70 parts by weight of component (A) with respect to 100 parts by weight of component (B). A method for manufacturing an additive. 2. The method for producing a papermaking additive according to claim 1, wherein component (A) is a saturated aliphatic monoalcohol having an alkyl group of 1 to 4 carbon atoms. Claim 1, wherein the use ratio of component (B) and component (C) is (epoxy equivalent of component (C))/(secondary amine equivalent of component (B)) = 0.8 to 2.0. Or the method for producing the papermaking additive according to 2. The method for producing a papermaking additive according to any one of claims 1 to 3, wherein the addition reaction is carried out at a temperature of 5 to 40°C and the cross-linking reaction is carried out at a temperature of 40 to 80°C. 5. The method for producing a papermaking additive according to any one of claims 1 to 4, wherein the viscosity of the aqueous solution of component (D) having a solid content of 25% by weight at a temperature of 25°C is 10 to 500 mPa·s.