JPH0613606B2 - Method for producing cationic water-soluble resin - Google Patents

Description

The present invention relates to a method for producing a cationic water-soluble resin. More specifically, the present invention relates to a method for quickly and safely producing, through simple steps, a cationic water-soluble resin that can be made highly water-soluble over a wide molecular weight range and is suitable for use as a drainage aid or retention aid during papermaking in the papermaking industry, as well as a flocculant and a drainage promoter.

BACKGROUND ART It is well known that polyalkyleneimines are useful in the papermaking industry as drainage improvers during papermaking, retention aids for fillers, dyes, pigments, fine fibers, etc., as flocculants for white water, and as flocculants and dewatering promoters for industrial wastewater and activated sludge in sewage treatment.

However, polyalkyleneimines are difficult to increase in molecular weight, which is one of the essential conditions for these applications, and are also very expensive.Furthermore, when used as a papermaking drainage retention improver, for example, they have the disadvantage that they are only effective in the neutral range and do not provide a stable effect over a wide range of pH.

As a product that has improved on these drawbacks, DE24,36,
Nitrogen-containing condensation products have been proposed in the specification of US Pat. No. 386. According to this specification, crosslinking of polyalkyleneimines with polyalkylene glycol polychlorohydrin ethers makes it possible to obtain high molecular weight nitrogen-containing condensation products that are economical and effective over a wide pH range.

However, in reality, the reaction between polyalkyleneimine and polyethylene glycol polyhalohydrin ether is slow, requiring a long time for production, and it is difficult to control the crosslinking reaction and obtain a product with the desired molecular weight, resulting in insufficient performance as a water treatment agent, and furthermore, there are problems in that only a low-concentration aqueous resin solution can be obtained.
In addition, for stable production, the reaction must be carried out at a uniform pH, which necessitates the addition of an alkaline substance, which is a problem.

Also known is a water-soluble crosslinked nitrogen-containing condensation product obtained by reacting polyethylene glycol-polypropylene glycol polychlorohydrin with ethyleneimine (DE 2,638,955). However, such a nitrogen-containing condensation product also has the problem that its solubility is insufficient, and only a low-concentration aqueous resin solution can be obtained, and it does not provide satisfactory performance as a water treatment agent.

The present invention is intended to solve the above problems, and therefore an object of the present invention is to provide a method for quickly and safely producing, through simple steps, a cationic water-soluble resin that can be made into a highly concentrated aqueous solution over a wide molecular weight range, and a water treatment agent that can exhibit remarkable effects over a wide pH range.

DISCLOSURE OF THE INVENTION The above object is to provide a method for producing a polyethylene glycol polyhalohydrin ether (A) comprising reacting 1 to 10 moles of epihalohydrin (b) per mole of polyethylene glycol with 100 parts by weight of polyethylene glycol polyhalohydrin ether, and 0.1 to 10 moles of an aziridine compound (B).
10,000 parts by weight of a cationic water-soluble resin (I) obtained by reacting (C) epihalohydrin and (D)
0.01 to 20 parts by weight of at least one selected from the group consisting of water-soluble or water-dispersible polyfunctional epoxy compounds,
This can be achieved by a method for producing a cationic water-soluble resin, which is characterized by carrying out a reaction until the viscosity reaches 0 to 2,000 cps.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing the relationship between the amount of cationic water-soluble resin added to pulp and the amount of drainage obtained by the method of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION The polyethylene glycol (a) used in the present invention preferably has a molecular weight in the range of 200 to 100,000, more preferably 600 to 50,000.
Most preferably, those having a molecular weight of 1,000 to 20,000 are suitably used, because if the molecular weight is less than 200, the cationic water-soluble resin is likely to gel during production, while if it exceeds 100,000, the reactivity with epihalohydrin decreases, making it impossible to obtain a cationic water-soluble resin that meets the object of the present invention.

Specific examples of the epihalohydrin (b) used in the present invention include epichlorohydrin, epibromohydrin, etc., but epichlorohydrin is preferably used because of its industrial availability.

In the production method of the present invention, it is essential to use polyethylene glycol (a) in the synthesis of polyethylene glycol polyhalohydrin ether (A). However, using other polyalkylene glycols, such as polypropylene glycol or ethylene glycol-propylene glycol copolymers, instead of polyethylene glycol (a) is not preferred because the water solubility decreases or, even if the polyethylene glycol (a) is water soluble, the viscosity of the aqueous solution increases and the effect as a water treatment agent also becomes significantly inferior.

The aziridine compound (B) used in the present invention is not particularly limited as long as it has one aziridine group per molecule. For example, a compound having a substituent on the aziridine ring may be used, or two or more of these aziridine compounds may be used.

Specific examples of such aziridine compounds include ethyleneimine, propyleneimine, butyleneimine, N-hydroxyethylethyleneimine, N-cyanoethylethyleneimine, N-methylethyleneimine, N-ethylethyleneimine, N-phenylethyleneimine, N-acetylethyleneimine, N-methacryloylaziridine,
Examples thereof include β-aziridinyl methyl propionate and β-aziridinyl ethyl methacrylate.

The aziridine compound (B) used in the present invention is one included in the above-mentioned range, but is preferably an alkyleneimine, more preferably ethyleneimine, from the viewpoints of economical advantages, reactivity with the polyethylene glycol polyhalohydrin ether (A), stable water solubility of the resulting cationic water-soluble resin, and performance as a water treatment agent.

To obtain polyethylene glycol polyhalohydrin ether (A) from polyethylene glycol (a) and epihalohydrin (b), a Bronsted acid or Lewis acid is added as a catalyst to polyethylene glycol (a) and reacted with epihalohydrin (b) at 30 to 150°C, preferably 50 to 100°C. Examples of Lewis acids and Bronsted acids include sulfuric acid, paratoluenesulfonic acid, perchloric acid, aluminum chloride, and boron fluoride ether complexes, with boron fluoride ether complexes being particularly preferred. The amount used is 0.01 to 1 wt%, preferably 0.02 to 0.5 wt%, relative to the polyethylene glycol (a). The ratio of polyethylene glycol (a) to epihalohydrin (b) is 1 to 10 moles, preferably 2 to 5 moles, of epihalohydrin (b) per mole of polyethylene glycol (a). That is, if the amount of epihalohydrin (b) is less than 1 mole, unreacted polyethylene glycol (a) will remain, making it impossible to obtain a cationic water-soluble resin that meets the object of the present invention, and the performance as a water treatment agent will also be insufficient.
On the other hand, if the amount exceeds 10 moles, gelation tends to occur during the production of the cationic water-soluble resin, which is not appropriate.

In the present invention, the cationic aqueous solution resin (I) is prepared by dissolving the polyethylene glycol polyhalohydrin ether (A) obtained by the above-mentioned procedure or an aqueous solution thereof in which an aziridine compound (B) is added.
The polyethylene glycol polyhalohydrin ether (A) is added to the aziridine compound (B) and subjected to a ring-opening addition polymerization reaction.
00/0.1 to 10,000, preferably 100/1 to 5
The reaction temperature is selected from the range of 0 to 200°C, preferably 50 to 100°C, at which the final concentration of the resulting cationic water-soluble resin is 5 to 100% by weight, preferably 20 to 70% by weight, in an aqueous solution, and is generally at a temperature at which the aziridine compound undergoes ring-opening polymerization, for example, 0 to 200°C, preferably 50 to 100°C.
It is preferable to carry out the process at a temperature of 0°C.
In an aqueous solution below 0°C, the reaction is slow, and the performance is insufficient when used as a water treatment agent. In addition, if the reaction temperature is below 0°C, the reaction rate is slow, while if it exceeds 200°C, it is difficult to control the reaction.

Cationic water-soluble resin (I) obtained by this method
The molecular weight can be adjusted to a wide range, for example, from 1,000 to 2,000,000, preferably from 5,000 to 10
0,000, and an aqueous solution of the cationic water-soluble resin (I) has a low viscosity.

The method for producing the cationic water-soluble resin of the present invention is achieved by reacting 100 parts by weight of the cationic water-soluble resin (I) obtained by the above-mentioned procedure with 0.01 to 20 parts by weight of at least one member selected from the group consisting of epihalohydrin (C) and water-soluble or water-dispersible polyfunctional epoxy compound (D) until the viscosity of a 20% by weight aqueous solution at 25°C reaches 100 to 2,000 cps.

Specific examples of the epihalohydrin (C) used in this case include:
As with the epihalohydrin (b), epichlorohydrin is preferred from the viewpoint of industrial availability.

The water-soluble or water-dispersible polyfunctional epoxy compound (D) is not limited as long as it has two or more epoxy groups in the molecule and is water-soluble or water-dispersible. Examples thereof include polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether,
Examples of such compounds include water-soluble polyfunctional epoxy compounds such as sorbitol polyglycidyl ether, and water-dispersible polyfunctional epoxy compounds such as bisphenol-type epoxy resins. It is preferable to use the polyethylene glycol diglycidyl ether represented by the formula (I) because it is water-soluble and therefore easy to handle, the reaction with the cationic water-soluble resin (I) can be carried out even at low temperatures and occurs rapidly, making it easy to adjust the molecular weight, and it is possible to obtain a cationic water-soluble resin having a high molecular weight and a low viscosity aqueous solution.

The amount of epihalohydrin (C) and/or water-soluble or water-dispersible polyfunctional epoxy compound (D) used in this reaction is as described above relative to 100 parts by weight of the cationic water-soluble resin (I), but if the amount used is less than 0.01 part by weight, no effect will be observed, while if the amount used exceeds 20 parts by weight, gelation will occur during the reaction.
It is preferable to use it in the range of 10 parts by weight, and in order to further enhance the effect as a water treatment agent, it is more preferable to use 0.1 to 10 parts by weight of the water-soluble or water-dispersible polyfunctional epoxy compound (D) alone.

The reaction continues until the viscosity of a 20% by weight aqueous solution of the resulting cationic water-soluble resin reaches 100 to 2,000 cps at 25°C. If the viscosity is less than 100 cps, the resin is insufficiently effective as a water treatment agent. Conversely, if the resin is allowed to react until the viscosity exceeds 2,000 cps, the resin is not more effective as a water treatment agent and simply results in time and economic losses.

In the reaction, the cationic water-soluble resin (I) is added in an amount of 10 to 30
%, preferably 15 to 25% by weight, of the resulting aqueous solution, to which epihalohydrin (C) and/or water-soluble or water-dispersible polyfunctional epoxy compound (D) is added, and 0 to
The reaction is preferably carried out at 80°C, more preferably at 20 to 60°C, in order to ensure smooth progress of the reaction.

Cationic water-soluble resin (II) obtained by this method
is, for example, 50,000 to 2,000,000, preferably 100,000 to 100
The water-soluble resin (I) has a molecular weight of 10,000 and is more effective as a water treatment agent over a wide pH range than the cationic water-soluble resin (I).

In these production methods of the present invention, the cationic water-soluble resin (I) is used as a raw material, and its molecular weight can be arbitrarily changed as desired. Therefore, even if the molecular weight of the cationic water-soluble resin (I) is low in order to obtain a highly concentrated aqueous solution, the epihalohydrin (C) can be easily added.
and/or a reaction with a polyfunctional epoxy compound (D), a cationic water-soluble resin with dramatically improved performance as a water treatment agent can be obtained.

The water treatment agent containing the cationic resin obtained by the above method has excellent water treatment effects over a wide pH range,
In addition, the water treatment effect is further improved over a wide pH range.

Such water treatment agents are particularly useful in the papermaking industry as drainage improvers, retention aids for fillers, dyes, pigments and fine fibers during papermaking, and flocculants for white water, as well as flocculants and dewatering promoters for activated sludge in industrial wastewater and sewage treatment.

The present invention will be specifically explained below with reference to examples, but the present invention is not limited by these examples.

Comparative Example 1 A flask equipped with a dropping funnel, a stirrer, a thermometer, and a reflux condenser was charged with 1,000 g of polyethylene glycol having a molecular weight of 1,800 and heated to 65° C. 2.1 g of boron trifluoride etherate was added as a catalyst, and then 113.1 g of epichlorohydrin was added dropwise over 20 minutes, and the reaction was continued for an additional 4.5 hours to obtain polyethylene glycol polychlorohydrin ether.

160 g of the obtained polyethylene glycol polychlorohydrin ether was diluted with 1,600 g of ion-exchanged water,
Heat to 80°C, then add 240g of ethyleneimine to
The reaction was continued for 6 hours, and the reaction was completed when it was confirmed by gas chromatography that the residual ethyleneimine was 1 ppm or less and the viscosity of the resin had become constant, thereby obtaining the cationic water-soluble resin (I) of the present invention.

The concentration of the resulting aqueous resin solution was 20% by weight, and the viscosity (B type) at 25°C was 360 cps. The reaction rate of the polyethylene glycol polychlorohydrin ether determined by analyzing chloride ions by ion chromatography was 95.2%.

Comparative Examples 2 and 3 and Production Examples 1 and 2 The types and amounts of raw materials used in Comparative Example 1 and the reaction conditions were as shown in Table 1.
The same procedure as in Comparative Example 1 was repeated to obtain cationic resins (2) to (5). The properties of the aqueous solutions of these resins were as follows:
The results were as shown in Table 1.

Comparative Example 4 300 g of a 20 wt % aqueous solution of polyethyleneimine having a molecular weight of 1,800 was placed in a flask and heated to 80°C, and 200 g of a 20 wt % aqueous solution of polyethylene glycol polychlorohydrin ether obtained by repeating the same procedure as in Comparative Example 1 was added dropwise over 5 hours, and the reaction was carried out for 6 hours while maintaining the pH of the system at 9.5 or higher with a 50% aqueous sodium hydroxide solution, thereby obtaining a cationic water-soluble resin (6). The concentration of the obtained resin aqueous solution was 20 wt % at 25°C.
The viscosity at 1000 kJ/min was 46.5 cps. The conversion rate of the polyethylene glycol polychlorohydrin ether was determined by analyzing chloride ions by ion chromatography to be 52.3%.

Comparative Example 5 The same procedure as in Comparative Example 2 was repeated to obtain polyethylene glycol polychlorohydrin ether.

40% by weight of polyethyleneimine with a molecular weight of 1,800 g
300 g of the aqueous solution was placed in a flask and heated to 80°C.
200 g of a 40% by weight aqueous solution of the polyethylene glycol polychlorohydrin ether was added dropwise over 5 hours, and the reaction was carried out while maintaining the pH of the system at 9.5 or higher with a 50% by weight aqueous solution of sodium hydroxide, resulting in gelation during the reaction.

Comparative Example 6 The same procedure as in Comparative Example 3 was repeated to obtain polyethylene glycol polychlorohydrin ether.

200 g of a 30 wt % aqueous solution of polyethyleneimine having a molecular weight of 1,200 was placed in a flask and heated to 80°C, and 200 g of the 30 wt % aqueous solution of the polyethylene glycol polychlorohydrin ether was added dropwise over 5 hours.
The pH of the system was adjusted to 9.0 with a 50% by weight aqueous solution of sodium hydroxide.
The reaction was continued for 6 hours while maintaining the temperature at or above 5 to obtain a cationic water-soluble resin (8). The concentration of the resulting aqueous resin solution was 30% by weight, and the viscosity at 25°C was 790 cps².
The viscosity of the aqueous solution adjusted to 0% by weight was 210 cps. The conversion of polyethylene glycol polychlorohydrin ether determined by chloride ion analysis was 79.6%.

Comparative Example 7: The same procedure as in Production Example 1 was repeated, except that an ethylene glycol-propylene glycol block copolymer (molecular weight 7,500) obtained by copolymerizing ethylene glycol and propylene glycol in a weight ratio of 80/20 was used instead of the polyethylene glycol used in Production Example 1, to obtain a cationic water-soluble resin (9). The resulting aqueous resin solution had a concentration of 50% by weight and a viscosity of 13,640 cps at 25°C, and an aqueous solution adjusted to a concentration of 20% by weight had a viscosity of 120 cps. The reaction rate of the polyalkylene glycol polychlorohydrin ether determined by analyzing chloride ions by ion chromatography was 82.2%.

Example 1 200 g of the cationic water-soluble resin obtained in Production Example 1 was mixed with 2
Dilute with 300 g of ion-exchanged water to a concentration of 0 wt %.
While stirring, 1.3 g (1.3 wt % based on the resin solid content) of ethylene glycol diglycidyl ether (where n=1 in formula (1)) was added. After that, the mixture was left to stand at 25° C. for 6 hours to obtain the cationic water-soluble resin (1.3 g) of the present invention.
The final viscosity was 385 cps at 25°C.

Examples 2 to 6 The same procedures as in Example 1 were repeated except that the types and amounts of raw materials used and the reaction conditions were as shown in Table 2.
The same procedure as in Example 1 was repeated to obtain cationic water-soluble resins (11) to (15). The properties of the aqueous solutions of these resins are shown in Table 2.

Comparative Example 8 100 g of the cationic water-soluble resin obtained in Production Example 2 was mixed with 2
Dilute with 100 g of ion-exchanged water to a concentration of 0 wt %.
While stirring, 12.5 g (25 wt % based on resin solids) of polyethylene glycol polyglycidyl ether (n=22) was added. After leaving it for 6 hours, a non-flowable gel-like substance was obtained. This substance was also insoluble in water.

Example 7 Cationic water-soluble resins (1), (2), (3), (6) and (8) obtained in Comparative Examples 1, 2, 3, 4 and 6
The cationic aqueous solution resin (10) obtained in Example 1 was tested for its effectiveness as a drainage aid during papermaking in the papermaking industry. The test conditions are shown below. The test results are shown in Figure 1.

Test conditions: Stock: 0.5% cardboard waste paper Evaluation method: The freeness was evaluated by adding the above cationic water-soluble resin or a comparative water-soluble resin to Stock 1 and measuring the amount of drainage using a Canadian freeness tester.

Example 8 Cationic water-soluble resins (10), (11) and (12) obtained in Comparative Examples 1, 2 and 3 and Comparative Examples 4 and 6
The effect of the cationic water-soluble resins (6) and (8) obtained in the above on filler retention during papermaking was tested. The test conditions are shown below. The test results are shown in Table 3.

Test conditions: Paper stock: LBKP Filler: Calcium carbonate, average particle size 0.2 microns (Shiraishi Kogyo Co., Ltd.) (30% to pulp) Procedure: 1% paper stock → Filler → Sizing agent → Aluminum sulfate → Dilution →
Chemicals → Papermaking, Yield: Filler retention was calculated from the ash content after heat treating the paper at 600°C for 20 minutes.

(Industrial Application Field) The production method of the present invention makes it possible to rapidly and safely produce, through simple steps, cationic water-soluble resins that can be made into highly concentrated aqueous solutions over a wide range of molecular weights.

Cationic water-soluble resin (I) obtained by the first method
The molecular weight can be adjusted over a wide range, and it is suitable for use as a water treatment agent such as a flocculant over a wide pH range.

Cationic water-soluble resin (II) obtained by the second method
In particular, it is possible to obtain a high molecular weight resin aqueous solution with low viscosity, and its effect as a water treatment agent over a wide pH range is enhanced compared to that of the cationic water-soluble resin (I), and it is suitable as a drainage improver in the papermaking industry and an agent for treating industrial wastewater.

Cationic water-soluble resin obtained by the third method (II
I) is a cationic water-soluble resin with an increased cationic strength, which can be used in water treatment agents over a wide pH range, and is particularly effective in the alkaline range.

The water treatment agent of the present invention contains at least one cationic resin selected from the cationic water-soluble resins (I), (II) and (III) described above. By freely selecting the type and use ratio of the resin depending on the desired purpose, the water treatment agent of the present invention can be used in a wide range of water treatment applications. In particular, the water treatment agent is suitable as a water treatment agent for papermaking in the papermaking industry and as a flocculant for activated sludge from industrial wastewater and sewage.

──────────────────────────────────────────────────── Continued from the front page (56) References: Patent Publication No. 51-37200 (JP, A) Patent Publication No. 53-28700 (JP, A)

Claims (14)

[Claims] 1. (A) A polyethylene glycol polyhalohydrin ether obtained by reacting 1 mole of (a) polyethylene glycol with 1 to 10 moles of (b) epihalohydrin, in an amount of 100 parts by weight of polyethylene glycol polyhalohydrin ether, in an amount of 0.1 to 10 moles of (B) aziridine compound,
100 parts by weight of a cationic water-soluble resin (I) obtained by reacting 1,000 parts by weight of (C) epihalohydrin and (D) at least one member selected from the group consisting of water-soluble or water-dispersible polyfunctional epoxy compounds, and a 20% by weight aqueous solution of the resin having a viscosity of 100 to 2,000 parts by weight at 25°C.
1. A method for producing a cationic water-soluble resin, comprising reacting the resin until the viscosity reaches 100,000 cps. 2. The method according to claim 1, wherein the epihalohydrin (b) is reacted in an amount of 2 to 5 moles per mole of the polyethylene glycol (a). 3. The method according to claim 1, wherein the aziridine compound (B) is reacted in an amount of 1 to 500 parts by weight per 100 parts by weight of the polyethylene glycol polyhalohydrin ether (A). 4. The method according to claim 1, which comprises reacting the polyethylene glycol polyhalohydrin ether (A) with the aziridine compound (B) in an aqueous solution at a temperature of 0 to 200°C so that the resulting cationic water-soluble resin (I) has a final concentration in the range of 5 to 100% by weight. 5. The method according to claim 1, wherein the polyethylene glycol polyhalohydrin ether (A) and the aziridine compound (B) are reacted at a temperature of 50 to 100°C in an aqueous solution so that the resulting cationic water-soluble resin (I) has a final concentration in the range of 20 to 70% by weight. [Claim 6] The method described in claim 1, which comprises reacting 100 parts by weight of the cationic water-soluble resin (I) with 0.1 to 10 parts by weight of at least one member selected from the group consisting of epihalohydrin (C) and water-soluble or water-dispersible polyfunctional epoxy compound (D). 7. The method according to claim 1, wherein 100 parts by weight of the cationic water-soluble resin (I) is reacted with 0.1 to 10 parts by weight of the water-soluble or water-dispersible polyfunctional epoxy compound (D). 8. The method according to claim 1, wherein the cationic water-soluble resin (I) is reacted with the epihalohydrin (C) and the water-soluble or water-dispersible polyfunctional epoxy compound (D) in an aqueous solution having a concentration of the cationic water-soluble resin (I) of 10 to 30% by weight at a temperature of 0 to 80°C. 9. The polyethylene glycol (a) has a molecular weight of 2
2. The method of claim 1, wherein the molecular weight is in the range of 00 to 100,000. 10. The process according to claim 1, wherein the epihalohydrin (C) is epichlorohydrin. 11. The method according to claim 1, wherein the aziridine compound (B) is an alkyleneimine. 12. The method according to claim 11, wherein the alkyleneimine is ethyleneimine. 13. The method according to claim 1, wherein the epihalohydrin (C) is epichlorohydrin. 14. The water-soluble or water-dispersible polyfunctional epoxy compound (D) represented by the following formula (1): 2. The method according to claim 1, wherein the compound is represented by the formula: (wherein n is an integer of 1 to 30).