JPS6346092B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing an aqueous cationic thermosetting resin solution with good storage stability. Conventionally, polyamide polyamine-epichlorohydrin resins useful as wet paper strength agents have been disclosed, for example, in Japanese Patent Publication No. 3547-3547 and Japanese Patent Application Laid-open No. 1983-3547.
It is known that it can be produced by the method of No. 159496. However, the polyamide polyamine/epichlorohydrin resins obtained by these conventionally known methods are not necessarily satisfactory in terms of storage stability, wet paper strength enhancing effect, and freeness improving effect. The inventors of the present invention have made intensive studies in view of the drawbacks of the resins produced by the above-mentioned known methods, and have found that by specifying the reaction conditions for producing polyamide polyamine/epichlorohydrin resin, it has an excellent wet paper strength enhancing effect. We succeeded in obtaining a resin with high storage stability. That is, the present invention synthesizes a polyamide polyamine by heating and condensing an aliphatic saturated dibasic acid and a polyalkylene polyamine, and then reacts this polyamide polyamine with epichlorohydrin in an aqueous solution to form a cationic thermosetting resin aqueous solution. In the manufacturing method, (1) aliphatic saturated dibasic acid and polyalkylene polyamine are reacted in a molar ratio of 1:1.0 to 1.2 such that a 50% aqueous solution of polyamide polyamine at 25°C has a viscosity of 300 to 1000 CPS. (2) Next, the above polyamide polyamine and 1.8 to 3.0 equivalents of epichlorohydrin based on its secondary amino group were reacted at 30 to 45°C for 30 to 120 minutes, and then the viscosity of a 30% aqueous solution of the product at 25°C was
A cation with a solid content concentration of 30 to 40%, which is characterized by reacting at 50 to 90°C to give 50 to 200 CPS, and (3) adjusting the PH of the reaction product at 25°C to 3 to 5. This is a method for producing a thermosetting resin aqueous solution. Examples of the aliphatic saturated dibasic acids used in the present invention include malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and industrially preferred is adipic acid. Examples of polyalkylene polyamines include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and iminobispropylamine. The molar ratio of aliphatic saturated dibasic acid and polyalkylene polyamine is 1:
Can be reacted at 1.0 to 1.2. If there is too much polyalkylene polyamine, it is difficult to increase the degree of polymerization of the polyamide polyamine, and the performance of the final product may be insufficient or it may take a long time to reach a predetermined degree of polymerization. On the other hand, if the amount of polyalkylene polyamine is too small, the polyamide polyamine will have a highly branched structure, resulting in gelation of the polyamide polyamine and a tendency for the stability of the final product to deteriorate. The reaction between the polyalkylene polyamine and the aliphatic saturated dibasic acid is preferably carried out in the presence of water in order to control the reaction heat generated during charging of the raw materials. The reaction is carried out by raising the temperature while removing the water produced. Reaction temperature is 110-250℃, preferably 160℃
~200℃. In this reaction, the viscosity of a 50% aqueous solution of the polyamide polyamine produced at 25℃ is
You can continue until you reach 300 CPS or more. The viscosity of a 50% aqueous solution of polyamide polyamine at 25℃ is
If it is less than 300 CPS, the wet paper strength enhancement effect of the final product may be insufficient, and when used in the papermaking process, strong foaming may occur, which is disadvantageous in terms of work.
Generally speaking, the higher the viscosity is, the greater the wet paper strength enhancement effect of the final product, and the greater its usefulness as a freeness improver.
Exceeding 1000 CPS is not preferable because the stability of the final product deteriorates. Therefore, the viscosity of the 50% aqueous solution at 25° C. can be arbitrarily selected from the range of 300 to 1000 CPS depending on the desired use and performance of the product. When the viscosity of the polyamide polyamine reaches a predetermined value, the reaction is terminated and the polyamide polyamine is diluted with water to prepare a 50% aqueous solution. The polyamide polyamine thus prepared is then reacted with epichlorohydrin in an aqueous solution. The amount of epichlorohydrin used in this reaction is 1.8 to 3.0 equivalents, preferably 1.8 to 2.4 equivalents, based on the secondary amino groups in the polyamide polyamine. If the molar ratio of epichlorohydrin is smaller than 1.8, the storage stability of the final product will be poor, and if the molar ratio of epichlorohydrin is larger than 3.0, it may take a long time to complete the reaction or the performance of the final product may deteriorate. . The reaction between polyamide polyamine and epichlorohydrin is usually carried out in an aqueous solution with a solid content concentration of 30-50%. In this case, after adding epichlorohydrin to a polyamide polyamine aqueous solution at 30℃,
After carrying out the reaction at 45℃ for 30 to 120 minutes,
The reaction is continued at a relatively high reaction temperature, i.e. 50-90°C. and 30 at 25℃ of the product
The reaction is carried out until the viscosity of the aqueous solution reaches 50-200 CPS. If the viscosity of the 30% aqueous solution of the reaction product is less than 50 CPS, the final product may not have sufficient performance as a wet paper strength enhancer, and if it exceeds 200 CPS, the stability of the final product may deteriorate. Once the viscosity of the reaction product reaches a predetermined range, the reaction product is cooled to below 45°C, preferably below 40°C, and if necessary diluted with water to a solid moisture concentration of 30-40%. . Then add acid to adjust the pH to 305. During this period, the temperature of the reaction product is preferably maintained at 30-40°C. Examples of acids used to adjust pH include hydrochloric acid, sulfuric acid, phosphoric acid, and acetic acid, with hydrochloric acid being preferred. The cationic thermosetting resin obtained by the method of the present invention has an excellent effect of increasing wet paper strength and improving water freeness. Furthermore, since the present resin aqueous solution has excellent storage stability, even an aqueous solution with a high solid content concentration of 30 to 40% can be stably maintained for a long period of time. The cationic thermosetting resin obtained by the method of the present invention is useful as a wet paper strength enhancer, as well as a freeness improver and a retention aid used in the paper manufacturing process, and is also useful for cellulose materials. It can also be used as a waterproofing agent, fiber treatment agent, binder, and flocculant. EXAMPLES The present invention will be described in more detail with reference to Examples below. Example 1 487 g (4.74 mol) of diethylenetriamine, 90 g of water, and adipic acid were placed in a 2-4 neck round bottom flask equipped with a thermometer, condenser, stirrer, and nitrogen inlet tube.
683 g (4.67 mol) was charged, heated externally with stirring, heated while removing water, and reacted at 180° C. for 4 hours. Then, 965 g of water was gradually added to obtain an aqueous polyamide polyamine solution. This polyamide polyamine aqueous solution has a solid content of 50.1% and a viscosity of 455CPS.
(25℃). In another flask, put 150 g of this polyamide polyamine aqueous solution (secondary amino group: 0.33
mol) and 201 g of water, and at 30°C add 60.5 g (0.65 mol) of epichlorohydrin. Raise the temperature,
Hold at 40℃ for 100 minutes, then raise the temperature to 65℃, perform the reaction at this temperature, and the viscosity of the reaction liquid is 140CPS.
When the temperature reached (25°C), it was cooled, and at 30°C, hydrochloric acid was added to adjust the pH to 4.2. The obtained product had a solid content of 32.1% and did not gel even when stored at 50°C for more than 3 months. Example 2 In a reactor similar to Example 1, 487 g (4.74 mol) of diethylenetriamine, 90 g of water, and 683 g of adipic acid were added.
g (4.67 mol), heated externally while stirring, heated to 180℃ while removing water, and heated at 180℃ for 4 hours.
After reacting for several minutes, 970 g of water was gradually added to obtain a polyamide polyamine aqueous solution. This polyamide polyamine aqueous solution has a solid content of 49.8% and a viscosity of 519CPS.
(25℃). Another flask was charged with 180 g of this polyamide polyamine aqueous solution (0.41 mol of secondary amino groups) and 231 g of water, and 68.5 g (0.74 mol) of epichlorohydrin was added at 30°C. Raise the temperature,
After being held at 40°C for 100 minutes, the temperature was raised to 65°C and the reaction was carried out at this temperature. When the viscosity of the reaction liquid reached 120 CPS, it was cooled and the pH was adjusted to 4.0 by adding hydrochloric acid. The resulting product had a solid content of 32.3% and did not gel for more than 3 months even when stored at 50°C. Example 3 In a reactor similar to Example 1, 487 g (4.74 mol) of diethylenetriamine, 90 g of water, and adipic acid were added.
683 g (4.67 mol) was charged, heated externally with stirring, heated while removing water, and heated to 200°C for 2 hours.
After reacting for a period of time, 970 g of water was gradually added to obtain a polyamide polyamine aqueous solution. This polyamide polyamine aqueous solution has a solid content of 49.8% and a viscosity of
It was 438CPS (25℃). In another flask, 150 g of this polyamide polyamine aqueous solution (secondary amino group
0.33 mol) and 188 g of water were charged, and 55.0 g (0.60 mol) of epichlorohydrin was added at 30°C. After raising the temperature and holding it at 40℃ for 100 minutes, the temperature was raised to 65℃,
The reaction is carried out at this temperature, and the viscosity of the reaction liquid is
When it reached 144 CPS, it was cooled and hydrochloric acid was added at 30°C to adjust the pH to 4.2. The resulting product had a solid content of 32.6% and did not gel for more than 3 months even when stored at 50°C. Example 4 In a reactor similar to Example 1, 482 g (4.67 mol) of diethylenetriamine, 92 g of water, and 683 g of adipic acid were added.
(4.67 mol) was charged, heated externally under stirring, and raised the temperature while removing water. After reacting at 180° C. for 5 hours, 975 g of water was added to obtain an aqueous polyamide polyamine solution. This polyamide polyamine aqueous solution had a solid content of 50.2% and a viscosity of 806 CPS (25°C). In another flask, add 150 g of this polyamide polyamine aqueous solution (0.32 mol of secondary amino groups) and 222 g of water.
g, add epichlorohydrin at 30°C while stirring.
71 g (0.77 mol) was added. Raise the temperature to 40℃
After holding for 100 minutes, the temperature was raised to 70°C, and the reaction was carried out at this temperature until the viscosity of the reaction solution reached 131 CPS, then cooled to 30°C, and hydrochloric acid was added to PH.
Adjusted to 4.0. The resulting product has a solids content of 32.1%
This product did not gel for more than 3 months even when stored at 50°C. Example 5 In a reactor similar to Example 1, 491 g (4.76 mol) of diethylenetriamine, 111 g of water, and 683 g of adipic acid were added.
(4.67 mol) was charged, heated externally under stirring, and raised the temperature while removing water. After reacting at 180° C. for 1 hour, 990 g of water was added to obtain an aqueous polyamide polyamine solution. This polyamide polyamine aqueous solution had a solid content of 50.0% and a viscosity of 350 CPS (25°C). In another flask, add 150 g of this polyamide polyamine aqueous solution (0.35 mol of secondary amino groups) and 109 g of water.
and epichlorohydrin at 30℃ under stirring.
58.3g (0.63mol) was added. Raise the temperature to 40℃
After holding for 60 minutes, the temperature was raised to 65°C, and the reaction was carried out at this temperature until the viscosity of the reaction liquid reached 238 CPS, then cooled to 30°C, and hydrochloric acid was added.
Adjusted to PH4.0. The resulting product has a solids content of 40.3%
Even when stored at 50°C, it did not gel for more than 3 months. Comparative Example 1 In Example 1, the amount of hydrochloric acid added was reduced,
Adjusted to PH5.6. The resulting product has a solid content of 33.0
%, but this product gelled in 43 days when stored at 50°C. Comparative Example 2 180 g (secondary amino group 0.41 mol) of the polyamide polyamine aqueous solution obtained in Example 2 (solid content 49.8%, viscosity 519 CPS) and 231 g of water were charged, and 68.5 g (0.74 mol) of epichlorohydrin was added at 30°C. After that, the temperature was raised to 65℃, the reaction was carried out at this temperature until the viscosity of the reaction liquid reached 120CPS, and then the temperature was raised to 30℃.
The mixture was cooled to 500 mL and hydrochloric acid was added to adjust the pH to 4.0. This product had a solid content of 31.9%;
When stored at °C, it gelled in 30 days. Comparative Example 3 150 g (secondary amino group 0.33 mol) of the polyamide polyamine aqueous solution obtained in Example 3 (solid content 49.8%, viscosity 438 CPS) and 175 g of water were charged, and 48.9 g (0.53 mol) of epichlorohydrin was added at 30°C. After that, the temperature was raised and held at 40℃ for 100 minutes, and then the temperature was increased to 65℃.
℃, and at this temperature the viscosity of the reactant decreases.
After carrying out the reaction until 142CPS was reached, the temperature was increased to 30°C.
The mixture was cooled to pH 4.2 and hydrochloric acid was added thereto to adjust the pH to 4.2.
The resulting product had a solid content of 32.7% and gelled in 30 days when stored at 50°C. Comparative Example 4 The same reaction as in Example 4 was carried out, but in the reaction between the polyamide polyamine aqueous solution and epichlorohydrin, the reaction was stopped when the viscosity of the reactant reached 30 CPS at 65° C., and the pH was adjusted to 4.0.
The obtained product has a solid content of 32.4%, and this
When stored at 50°C, it did not gel for more than 3 months. Comparative Example 5 150 g (secondary amino group 0.32 mol) of the polyamide polyamine aqueous solution obtained in Example 4 (solid content 50.2%, viscosity 806 CPS) and 270 g of water were charged, and 94.8 g (1.02 mol) of epichlorohydrin was added at 30°C. After that, the temperature was raised and held at 40℃ for 100 minutes, and then heated to 65℃.
The temperature was raised to ℃, the reaction was carried out until the viscosity of the reactant reached 129 CPS, the temperature was cooled to 30℃, and hydrochloric acid was added.
Adjusted to PH4.0. The resulting product has a solids content of 30.9%
Although this product was stored at 50°C, it did not gel for more than 3 months. Comparative Example 6 Into the same apparatus as in Example 1, 491 g (4.76 mol) of diethylenetriamine, 90 g of water, and 683 g of adipic acid were added.
(4.67g) and heated from the outside while stirring.
The temperature was raised while removing water, and the mixture was reacted at 180° C. for 4 hours, and then 980 g of water was added to obtain an aqueous polyamide polyamine solution. This polyamide polyamine aqueous solution had a solid content of 50.2% and a viscosity of 250 CPS (25°C). In another flask, add 150 g of this polyamide polyamine aqueous solution (secondary amino group, 0.35 mol) and 197 g of water.
Prepare 58.3g of epichlorohydrin at 30℃
After adding (0.63 mol), the temperature was raised to 40℃ and 100
The temperature was then raised to 65°C, and the reaction was carried out at this temperature until the viscosity of the reaction solution reached 126 CPS, and then cooled to 30°C and hydrochloric acid was added to make the pH 4.3.
Adjusted to. The resulting product had a solids content of 32.4%, but did not gel for more than 3 months when stored at 50°C. Reference Example 1 The paper strength enhancing effect of each resin obtained in Examples 1 to 5 and Comparative Examples 4 to 6 was investigated. Paper making and paper strength measurement conditions are as follows. (1) Sample pulp NBKP, freeness 370ml (2) Resin addition rate 0.3%/pulp (3) Sulfuric acid band addition rate 0.01%/pulp (4) Average metric basis weight 120g/m ² (5) Paper machine Square sheet machine (Paper size 25cm x
25cm) (6) Pretreatment conditions (20℃, humidity 65%) x 24 hours (7) Heat treatment conditions 105℃ x 10 minutes

【table】

【table】

Claims (1)

[Claims] 1 A polyamide polyamine is synthesized by heating and condensing an aliphatic saturated dibasic acid and a polyalkylene polyamine, and then this polyamide polyamine is reacted with epichlorohydrin in an aqueous solution to produce a cationic thermosetting resin. In the method for producing an aqueous solution, (1) the viscosity of a 50% aqueous solution at 25°C of a polyamide polyamine produced at a molar ratio of aliphatic saturated dibasic acid and polyalkylene polyamine of 1:1.0 to 1.2 is 300 to 1000 cps. (2) Then, the above polyamide polyamine and 1.8 to 3.0 equivalents of epichlorohydrin to its secondary amino group were reacted at 30 to 45°C for 30 to 120 minutes, and then a 30% aqueous solution of the product at 25°C was reacted. The viscosity
A cation having a solid content concentration of 30 to 40%, which is characterized by reacting at 50 to 90°C to give a reaction rate of 50 to 200 cps, and (3) adjusting the pH of the reaction product at 25°C to 3 to 5. A method for producing a thermosetting resin aqueous solution.