JPS58152004A - Production of novel cationic polymer - Google Patents

Abstract

PURPOSE:The reaction of an acrylamide polymer containing quaternary ammonium groups with a hypohalite salt in the presence of alkali gives the titled polymer with high stability to shelf tests, having cationic groups introduced efficiently. CONSTITUTION:An acrylamide polymer containing quaternary ammonium groups obtained from acrylamide and a monomer containing a quaternary ammonium group is made to react with 50-70mol%, based on 100mol% of amide groups in the acrylamide polymer, of a hypohalite salt or a substance capable of forming a hypohalite salt in the presence of an alkali to produce the objective polymer containing 5-70mol% of primary amino groups and 2-20mol% of quaternary ammonium groups.

Description

[Detailed Description of the Invention] Related. More specifically, the present invention relates to a method for producing a novel cationic polymer having a primary amino group and a quaternary ammonium group in its side chain.

Conventionally, primary amino groups can be introduced into acrylamide polymers by reacting them with caustic soda and sodium hypochlorite in water (Ho7man decomposition reaction), and the resulting product can be used as a papermaking N11 product. It is known to be scaly. However, when such a product is stored as an aqueous flI solution, there is a problem in that most of the amino groups disappear after being left at room temperature for several days, probably because the produced amino groups are extremely unstable. Therefore, when the Hofmann degradation product is used as a paper-making diarrhea product, it does not exhibit sufficiently satisfactory performance.

Various proposals have been made to eliminate this problem. For example, Japanese Patent Publication No. 54-15.791, Japanese Patent Publication No. 54-15.
No. 5-108,405 and JP-A-54-144,29
Each publication No. 6 discloses that when an acrylamide polymer is subjected to Hoffmann decomposition to generate a primary amino group, a low-molecular compound having a quaternary ammonium group is added and then reacted with the polymer. A polymer having both a primary amino group and a quaternary ammonium group and a method for producing the same have been disclosed. In the case of this polymer, since the quaternary ammonium group contained therein has superior stability compared to the primary amine 7 group, the polymer itself also contains only the above-mentioned primary amino group. It has better storage stability than Hofmann decomposition products of acrylamide.

However, low molecular weight compounds having a quaternary ammonium group have a low reaction rate to polymers, making it difficult to efficiently introduce stable cationic groups (quaternary ammonium groups) into polymers. The content of quaternary ammonium groups in the product is insufficient. Therefore, when this polymer is used as a papermaking chemical, there is almost no difference in storage stability and performance from the aforementioned acrylamide polymer having only primary amino groups, and as a product it is I'm still not satisfied with it. Furthermore, when the polymer is used as a paper-making chemical, unreacted residual low-molecular compounds may contaminate white water during the paper-making process.

Further, JP-A-54145.790 discloses that a cationically modified polyacrylamide can be obtained by adding a polyamine when subjecting polyacrylamide to a Hoffmann decomposition reaction. However, even with such a method, the cationic group cannot be efficiently introduced because the reactivity between the polyamine and the polymer is low. In addition, the cationic modified product obtained by this method has 7 primary to tertiary amide groups, and
Not only when a large number of primary and secondary amine 7 groups are introduced, but even when a large number of 6th class amine 7 groups are introduced, the expression of cationic properties of these polymers is hardly observed in the high pH range. do not have. Therefore, when the daughter cationic modified product is used as a papermaking chemical, the area in which it can be used properly is limited to a narrow range from the viewpoint of fixability to pulp.

Like temporary fixing, Hofmann decomposition products of conventionally known polyacrylamides or their derivatives are stable on storage and have high pH.
These days, there is a strong desire in the paper industry for the development of even better paper-making chemicals.

The inventors of the present invention have conducted intensive research in order to develop an excellent papermaking chemical that solves the conventional problems such as temporary fixing. By Hofmann decomposition, cationic groups have excellent storage stability, efficiently introduce cationic groups, and when used as papermaking products, they have excellent fixation to pulp and cationic properties in the Takato region. This discovery led to the completion of the present invention.

That is, the present invention is characterized in that an acrylamide-based polymer having a quaternary ammonium group and a hypohalite or a substance capable of forming a hypohalite are reacted in the presence of an alkali. first on the polymer side chain
The present invention relates to a method for producing a cationic polymer having a primary amino group and a quaternary ammonium group.

Used in the present invention. The acrylamide-based polymer having quaternary ammonium groups (hereinafter referred to as #!quaternary cationic polymer) contains at least (a) acrylamide and (b) a monomer having quaternary ammonium groups. It can be obtained by copolymerizing a monomer mixture. Also, if desired, during the copolymerization, lc) the above (a) and (
It is also possible to use any monomer copolymerizable with b).

For example, the monomer of (b) has the following general formula % formula %
(: (1) (In the formula, R□ is a hydrogen atom or a methyl group, A has a carbon number of 2
~4 fullkylene group or hydroxyl group-containing alkylene group, B
is an alkylene group having 1 to 4 carbon atoms, R2, R3, R4, R
5, R6, R7J8, R15 and RIO are alkyl groups or alkyl groups containing a water group, R is a hydrogen atom or an alkyl group, X- is a chlorine ion, bromide ion, sulfate ion, methylsulfate ion or p-toluenesulfone A quaternary ammonium salt represented by an acid ion) is used.

The compound represented by the general formula (1) is a quaternary ammonium salt of dialkylaminoalkyl ester of acrylic acid or methacrylic acid, and specific examples of such dialkylaminoalkyl ester group include banma, dimethylaminomethyl group, diethylaminomethyl group. group, dimethylaminoethyl group, diethylaminoethyl group, 6-diethylaminopropyl group, 2-dimethylaminoisopropyl group, and the like.

The compound represented by the general formula (1) is a quaternary ammonium salt of an N-dialkylaminoalkyl substituent of acrylic amide or methacrylic amide, and specific examples of such dialkylaminoalkyl substituent include dimethylaminoethyl group, dimethylaminopropyl group, dimethylaminobutyl group, diethylaminopropyl group, diethylaminobutyl group, g-n-tetrabyl aminoethyl group, g-n, propylaminobutyl group, and the like.

The compound represented by the general formula (1) is a quaternary ammonium salt derived from diallylamine, and specific examples of ~ or ~ include methyl group, ethyl group 1 n-propyl group, hydroxyethyl group, benzyl group etc.

The compound represented by the general formula (g) is a quaternary ammonium salt (pyridinium salt) derived from vinylpyridines, and examples of such vinylpyridines include 2-vinylpyridine, 4-vinylpyridine, and 2-vinylpyridine. Examples include 6-methylpyridine and 2-vinyl-5-ethylpyridine.

Quaternizing agents used in producing quaternary ammonium salts such as temporary fixing include ethyl bromide, butyl bromide, benzyl bromide, methyl chloride, ethyl chloride, benzyl chloride,
Examples thereof include alkyl halides or aralkyl halides such as methyl iodide, and inorganic acid esters such as dimethyl sulfate, diethyl sulfate, dimethyl sulfite, and dimethyl phosphorus.

Further, as specific examples of the monomer of the above To), for example, acrylic acid, methacrylic acid, vinylsulfonic acid, styrene,
7-ionic monomer such as sulfonic acid or carbon Wk1
-8 esters of alcohols with acrylic acid or methacrylic acid, 7-ionic monomers such as methacrylamide, acrylonitrile, styrene, vinyl acetate, and methyl vinyl ether.

The quaternary cationic polymer used in the present invention can be prepared by the method described above (i.e., by the following method. In other words, the quaternary ammonium group-containing monomer of (b) above is added to the corresponding monomer having a quaternary ammonium group. Instead of the tertiary amine monomer, the above (&) is copolymerized (and (c) is added if desired), and then the 6th amino group in the resulting copolymer is A quaternary cationic polymer can be obtained by quaternizing with the quaternizing agent.

The copolymerization reaction of suspending the fs quaternary cationic polymer used in the present invention can be carried out by various conventionally known methods.

For example, a water-soluble radical generating catalyst such as hydrogen peroxide, potassium persulfate, or ammonium persulfate is added to the monomer mixture 1.
If used in an aqueous medium with a monomer concentration of 5 to 50% and stirred for 1 to 10 hours at a temperature of about 50 to 95° good. At this time, chain transfer of various water-soluble chemicals such as buffering agents such as sodium bicarbonate, sodium monophosphate or sodium diphosphate, reducing agents such as dimethylamine and sodium thiosulfate, isoprene alcohol, allyl alcohol, etc. It is also possible to use a suitable agent in the same manner as in the conventional method.

According to the method of the present invention, after obtaining the quaternary cationic polymer, it is reacted with a hypohalogen salt or a substance capable of forming hypohalogen gas in the presence of an alkali to form a quaternary cationic polymer. It is essential to introduce 7 primary amide groups. For this reaction step, a conventionally known reaction method known as so-called Hofmann decomposition reaction can be employed. That is, it is carried out by a method of reacting the quaternary cationic polymer with a hypohalite or a substance capable of forming it (for example, a mixture of halogen gas and an inorganic alkali). The temperature at this time is preferably as low as possible from the viewpoint of decomposing the hypohalite, generating primary amino groups by Hofmann decomposition, and suppressing crosslinking of the polymer, preferably 10 to +50, more preferably is suitably in the range of 0 to 25°0, whereby the reaction is completed in a short time and primary amino groups are introduced into the acrylamide polymer.

Examples of hypohalite salts used in the present invention include sodium hypohalite, sodium hypobromite, and potassium hypochlorite. The amount is arbitrarily adopted in the range of about 5 to 70 mol per 100 examples, and is determined as appropriate depending on the required properties and performance of the final product.

Further, a typical substance capable of forming the hypohalite used in the present invention is a mixture of a halogen gas and an inorganic alkali. Specific examples of halogen gases used in such cases include fluorine gas, chlorine gas, bromine gas, and iodine gas, and specific examples of inorganic alkalis include caustic potash, caustic soda, and charcoal lithium. .

The quaternary cationic polymer obtained by the method of the present invention can be used as a papermaking additive (e.g., a paper strength enhancer, a p-aqueous property improver,
It can be effectively used as a filler retention agent, size fixing aid, flocculant, etc.).

When the polymer is used for such purposes, the monomer unit having a primary amino group is usually 5 to 70 mol%, preferably 5 to 70 mol%, from the viewpoint of fixability to pulp or filler. It is appropriate that the proportion of monomer units having a cationic group is 2 to 20 mol%, preferably 2 to 10 mol%.

As mentioned above, the monomer component (a) is not an essential component contained in the polymer used in the method of the present invention.

However, when providing the #114 cationic polymer for the above uses, the monomer component (o) is preferably used to change its properties depending on the use. In this case, the anionic monomer is used in an amount such that the number of carboxyl group-containing monomer units in the polymer is up to 20 moles, preferably up to 10 moles, and the nonionic monomer is The amount can be used as long as the resulting polymer remains water soluble, usually up to 60 molar.

If the content of primary amino group-containing monomer units in the quaternary cationic polymer is less than 5 moles, it will have poor fixing properties as a papermaking additive; Even if the molar strength is increased, no particularly significant improvement is observed in terms of fixing properties and chemical performance (for example, paper strength effect, water resistance, etc.).

Furthermore, if the content of the quaternary cationic group-containing monomer unit in the quaternary cationic polymer is less than 2 moles, the cationic property will be poorly expressed when used in a high pH environment. On the other hand, if more than 20 mol is used, the fixing properties in the high press area will not be particularly improved, and it will be disadvantageous from an economic point of view, so either case is not preferable.

Furthermore, when the anionic monomer is contained in the quaternary cationic polymer, if it exceeds the above range, that is, 20 mol%, the paper strength enhancing effect and/or
This is not preferable because the effect of improving P water properties is reduced.

Next, the method of the present invention and the properties of the quaternary cationic polymer obtained thereby as a paper-making agent will be explained in more detail by reference examples, examples, and test examples. It is not limited only to the examples. In addition, reference example G listed below is used in the method of the present invention.
This is an example of producing an acrylamide yarn polymer (base polymer) having grade ammonium groups.

Reference Example 1 Soft water 23009, acrylamide 446 in a Yotsurokorpen equipped with a stirrer, thermometer, cooler and nitrogen introduction tube
g and methacrylamide propyltrimethylammonium chloride (154 g) were charged, the temperature was raised to 65° CJ under a nitrogen gas flow, and 18 g of a 10% aqueous solution of ammonium persulfite and 89 g of a 10% aqueous solution of aqueous sodium sulfite were added to polymerize. The reaction started. 3 at 80°O with stirring
After completing the polymerization reaction by keeping it warm for an hour, use soft water with 1080
9 to form an acrylamide-methacrylamidopropyltrimethylammonium chloride (molar ratio 90/10) copolymer with a nonvolatile concentration of 15% and a viscosity of 9!00 cP (
A solution (hereinafter referred to as P) was obtained.

Reference Examples 2 to 7 Polymerization reactions were carried out in the same manner as in Example 1, except that the types and amounts of monomers used were changed as shown in Table 1. P2, P
3, P4, P5, P6, Pwa) solutions were obtained. Table 1 shows the viscosity of each copolymer solution obtained.

The abbreviations used in Table 1 indicate the following, respectively.

MAP: methacrylamide probilt IJ methyla.

Ammonium chloride DMO: Methacryloyloxysutyl 9-methylammonium chloride QA: 2-Hydroxy-3-methac 1-noroxypropyl F trimethylammonium chloride DMD: Dimethyldiallylammonium chloride vp: 2-vinylpyridine-N-methylchloride AM Niacrylamide AA Niacrylic Acid IM Side 1 300 g (0,5
2 mol), the temperature was adjusted to 1500, and then a 12.5% pure hypochlorous acid sorter 51.29 (0.05
2 mol) and 48% caustic soda aqueous solution 5.2 g (0
, 062 mol) was added dropwise over 30 minutes. After the reaction was completed by keeping it at 25°0 for 2 hours with stirring, 10% hydrochloric acid was added to adjust the pi (pi) to 4.5, and then water was added to give a
A solution of grade cationic polymer (hereinafter referred to as C grade) was obtained.

The viscosity of the polymer solution at 2500 was 950 cp. Further, the content of monomer units containing 7 primary amine groups in C0 was 10-mol%, and the content of monomer units containing quaternary ammonium groups was 10-mol%.

Examples 2 to 8 Same as Example 1 except that at least one of the type of base polymer used and the amount (mol%) of sodium hypochlorite and caustic soda used relative to the base polymer was changed as shown in Table 2. Experiments were conducted using quaternary cationic polymers (02, C3, C4,05, C
6,07, C8) was obtained. Got 0
□The viscosity of the 7% solution of ~8, the content of the monomer unit containing 7 primary amine groups in 02~8 (hereinafter referred to as the amino group content), and the content of the monomer unit containing the quaternary ammonium group The content rates (hereinafter referred to as ammonium group content rates) are shown in Table 2.

Comparative Example 1 2,500 g of soft water and 600 g of acrylamide were charged in a four-wheel colben equipped with a stirrer, a thermometer, and a nitrogen inlet tube, and the temperature was raised to 55 aO under a nitrogen gas flow, and a 10% aqueous solution of ammonium persulfate 1+6F and acidic sulfite were added. Polymerization was started by adding 7 g of a 10% aqueous solution of soda. After completing the polymerization reaction by keeping the temperature at 80°0 for 3 hours while stirring, add 1083 g of soft water to make a non-volatile concentration of 15%.
An acrylamide polymer solution with a viscosity of 7800 cP was obtained.

Next, the acrylamide polymer solution 2469 was temporarily fixed in a Yotsurokolben equipped with a stirrer, a thermometer, and a dropping funnel.
(0.52 mol) and adjusted the temperature to 1500℃,
Next, 62.4g of sodium hypochlorite with a purity of 12.5% (
0,104 mol) and 48% caustic soda 10.49 (0,
124 mol) was added dropwise over 30 minutes. After the reaction was completed by keeping it at 25oC for 2 hours with stirring, the pH was adjusted to 4 or 5 by adding 10% hydrochloric acid.
Then, water was added to obtain a 7% primary amide 7 group-containing polymer (hereinafter referred to as D□) solution in terms of base polymer. The viscosity of the solution at 25°O is 790 op,
The amide 7 group content in D0 was outside 18 moles.

Comparative Example 2 The amount of sodium hypochlorite with an active ingredient of 12.5% was 12.
The experiment was carried out in the same manner as in Comparative Example 1, except that the amount of 48% caustic soda aqueous solution was 20.89 (0,248 mol), and 7% in terms of base polymer. The primary amino group-containing polymer (hereinafter referred to as D2) was dried up. The viscosity of the D2 solution at 25'O was 210 oP, and the content of amide 7 groups in D2 was outside of 57 moles. The amino group content and ammonium group content of were determined according to the following method.

(13 Determination of ammonium group content in base polymer Toluidine blue was used as an indicator, and potassium polyvinylsulfonate (PV8K) was added dropwise under alkaline conditions to determine the content.
S No. 6, 309 (1976)) 0 (2) Determination of the sum of the ammonium group content and amino group content in the cationic polymer after Hoffman decomposition The amount was determined in the same manner as in method (1).

(8) Determination of the amino group content in the cationic polymer after Hoffman decomposition The value obtained by subtracting the measured value in (1) from the measured value in (2) above was taken as the value.

It was confirmed by the following analysis that the quaternary cationic group was not chemically changed by Hoffmann decomposition. That is, the cationic polymer after Hofmann decomposition was precipitated with methanol under acidic conditions, then purified and dried, and then redissolved in heavy water (D20) and 'H-NMR.
So the J value is 6.5ppI! The I peak (based on the OH of the quaternary ammonium group) was quantified, and it was confirmed that it was chemically stable.

Next, test examples of the polymers obtained in the temporary fixing examples and comparative examples as papermaking additives will be given.

In addition, the following tests of mechanical properties were carried out in accordance with the following methods.

(1) Tensile strength J engineering sp 8115 (2) Internal strength Tappi RO508Internalbon
dte8ter (3) Bursting strength J Engineering SP 8131 (4) Compressive strength J Engineering SP 8126 (5) Steckigt sizing degree J Engineering SP 81125 for 3 hours. ) (7) P water-based J-engineering p 8
121 Test Example 1 (Neutral Paper Making Test) Pulp (L-BKP/N-BKP=85/15.500
csf), 20% of 0ILOO3 was added to the pulp, 0.4% of the polymer obtained in Examples 1 to 8 or Comparative Examples 1 to 2 was added to the pulp, and 5TK-900 (
0.1% of an alkylcutene dimer sizing agent manufactured by Arayo Kagaku Kogyo Co., Ltd. was added to the paper, and the paper was made to have a basis weight of 60 g//'□ using a Tappi Standard Sheet Machine. The pH at the time of paper making was 8.0.

Then 7kg/Cm2 for 3 minutes and 10 to 910m2
Press and dehydrate for 2 minutes at
After drying with Lye Y- for 1 minute, the humidity was adjusted and paper was obtained. Table 3 shows the specific test results for the paper produced.

Sixth! ! ! *Blank test test example 2 (acidic papermaking test) In a 1% aqueous dispersion of pulp (L-BKPs 460aa!), talc was added to the pulp at 15%, and a reinforcing rosin agent was added to the pulp at 0.6%, Examples 1 to 8 above. Or add 0.5% of the polymer obtained in Comparative Examples 1 and 2 to the pulp and 1% of sulfuric acid to the pulp, and make paper using a Tatsubi Standard Sheet Machine to have a basis weight of 559/d. did. The tsubo at the time of paper making was 5.0. Then, press dehydration, drying and humidity control were carried out in the same manner as in Test Example 1 to obtain paper. The results of the paper property tests observed are shown in Table 4.

Table 4 Test Example 5 (Aqueous Test) To a 1% aqueous dispersion of pulp (L-UKP 580mja asf) was added 6% of sulfuric acid based on the pulp, and then sulfuric acid was added to a 1% aqueous dispersion of pulp (L-UKP 580mj asf), 0.01% of the above-mentioned polymer was added to the pulp, and an aqueous test was conducted using a Canadian Prenes tester.The results are shown in Table 5.

Table 5 *Blank test

Claims (1)

[Claims] 1. A polymer side chain characterized by reacting an acrylamide-based polymer having a quaternary ammonium group with a hypohalite or a substance capable of forming a hypohalite in the presence of an alkali. A method for producing a cationic polymer having a primary amino group and a quaternary ammonium group.