JPH0674287B2 - Method for producing water-soluble cationic polymer - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a water-soluble cationic polymer by photopolymerization. More specifically, coarse particles after cutting and crushing should adhere to each other. The present invention relates to a method capable of smooth cutting and coarse crushing without the presence of a metal.

[Prior Art] Water-soluble polymers are widely used in many industrial fields,
It has an important industrial position. Typical examples of its use are solid-liquid separation agents in the manufacturing process; coagulating sedimentation agents in industrial wastewater treatment; sludge dewatering aids in sewage and human waste treatment; paper-making agents such as paper-strengthening agents and filler retention improvers; Soil conditioners, thickeners, petroleum recovery agents, etc. may be mentioned.

Although various methods are used for producing a water-soluble cationic polymer, the most general method is an aqueous solution polymerization method.

For example, JP-A-52-126494 and JP-A-53-133287 disclose a method for producing a water-soluble cationic polymer in a sheet form.

Further, a method of internally or externally adding polyethylene glycol to a polymerization system in order to prevent the polymer from sticking to the inner wall of a container used during production is disclosed in JP-A-52-85283 and JP-A-53-81555. It is disclosed.

[Problems to be Solved by the Invention] However, when the sheet of the water-soluble cationic polymer produced by the above method is cut and then crushed, the cut pieces, coarse particles, etc. of these polymers are cut or coarsely cut. Attached to the rotary blade in the device to be crushed, the fixed blade, or the inner surface of the device,
It often happens that the operation of the device becomes difficult and the process must be stopped.

There is also a problem that the cut or roughly crushed polymers stick to each other and cannot be continuously fed to the next step.

For such problems, a method of internally adding polyethylene glycol and externally adding polyethylene glycol is known, but in that case, a large addition amount is required, and the adhesiveness is restored during the next process transfer or drying. Then, there is also a problem that cut pieces or coarse particles stick to each other and become lumpy.

[Means for Solving Problems] As a result of intensive studies made by the present inventors in view of the above-mentioned conventional techniques, the use of a specific surfactant to be described later at the time of cutting and crushing solves the above problems. The inventors have found out what is possible and have completed the method of the present invention.

The method for producing a water-soluble cationic polymer of the present invention was obtained after polymerizing a water-soluble cationic monomer containing a photopolymerization initiator by light irradiation in a container having a depth of 50 mm or less. The sheet-shaped polymer surface or the cutting blade of a device for cutting the polymer is cut while supplying at least one surfactant selected from the group consisting of a cationic surfactant and a nonionic surfactant, It is characterized by being continuously crushed.

As the water-soluble monomer used in the present invention, any water-soluble cationic polymer can be used as long as it can form a water-soluble cationic polymer.

For example, nonionic monomers such as acrylamide, methacrylamide, dimethylacrylamide, and hydroxyethyl methacrylate; dimethylaminoethyl (meth) acrylate and salts thereof, diethylaminoethyl (meth) acrylate and salts thereof, 3-dimethylamino-2-hydroxypropyl. (Meth) acrylate and salts thereof, dimethylaminopropyl (meth) acrylamide and salts thereof,
And a monomer obtained by quaternizing the above tertiary amine with methyl chloride, methyl bromide, methyl iodide, dimethyl sulfate, etc., a cationic monomer such as a salt of dimethyl diallyl ammonium, a salt of diethyl diallyl ammonium;
Etc.

These monomers may be used alone or in combination of two or more. Further, if necessary, other monomers such as acrylonitrile and vinyl acetate may be added and used as long as the object of the present invention is not impaired.

As the photopolymerization initiator used for the polymerization of the water-soluble monomer, a generally known photopolymerization initiator can be used and is not particularly limited. For example, benzoin,
Examples thereof include benzoin alkyl ether and anthraquinone derivatives. The amount of the photopolymerization initiator used is in the range of 10 to 2000 ppm with respect to the water-soluble monomer. When the amount of the photopolymerization initiator used is out of the above range, it takes a very long time for the polymerization, the obtained polymer is colored, and further, the molecular weight is lowered, which is disadvantageous.

The concentration of the water-soluble monomer in carrying out the present invention is not particularly limited, but is 25% by weight to 90% by weight, preferably 40% by weight.
Adjust by mixing with water as above. If the monomer concentration is low, the cost for drying and shipping will increase,
Further, it takes a long time to obtain a high molecular weight polymer. On the other hand, if the monomer concentration is too high, the uniformity of the system cannot be maintained.

The container used for the polymerization is not particularly limited as long as it can form a sheet-like polymer having a thickness of 50 mm or less, for example, a box-shaped container having a weir of 50 mm or less in height, or both ends of an endless belt. A continuous polymerization type container having a weir having a height of 50 mm or less is preferable. It is also preferable that the thickness of the bag is 50 mm or less, such as a bag of a transparent film. Depth is
When a container having a diameter of more than 50 mm is used, it becomes difficult to control the temperature in the polymerization step, and sufficient irradiation of light cannot be performed, so that a polymer having high uniformity cannot be obtained.

Polymerization in a container, the above-mentioned polymerization solution is injected to form a sheet-like polymer having a desired thickness, preferably 1 mm or more and 50 mm or less, and in a nitrogen atmosphere, its upper surface is covered with a light-transmitting film. The main polymerization is carried out by irradiating with light. In this main polymerization, the polymerization is advanced to such an extent that at least a gel component capable of removing the polymer from the container is formed.

As the light used in the main polymerization of the present invention, by combining with a photopolymerization initiator, light of various wavelengths can be adopted, but from the viewpoint of absorption by the monomer itself, photon energy, 300-500 nm It is desirable that the light has a wavelength in the range. Examples of the light source that gives light of 300 to 500 nm include a high pressure mercury lamp, an ultrahigh pressure mercury lamp, and a fluorescent chemical lamp. A particularly preferable light source is a fluorescent chemical lamp manufactured by Mitsubishi Electric Corporation.

In the method of the present invention, the sheet-shaped polymer is cut and crushed preferably by using a known cutter or a crusher, and in particular, a crusher is combined immediately below the cutter as shown in the figure. Devices of construction are preferred. In the apparatus shown in the figure, the polymer sheet 1 is cut into predetermined strips 3 by a cutting unit 2, and the strips 3 are coarsely crushed by a crushing unit 4 located immediately below the cutting unit 2 into a crushing unit 5. Become. Reference numeral 6 in the drawing denotes a nozzle for spraying a surfactant, which will be described later, onto the polymer sheet, the cutting section 2, the crushing section or the inner wall of the apparatus.

The method of the present invention is characterized by advancing the operation while supplying a surfactant to be described later to the surface of the polymer sheet, the cutting blade in the apparatus, etc. in the course of cutting and crushing.

At this time, as the method of supplying the surfactant, methods such as roller coating, brush coating, and spraying can be applied, but as described above, the method of spraying from the nozzle 2 is suitable.

As the surfactant used in the present invention, a cationic surfactant, or an alcohol-based defoaming agent or a silicon-based defoaming agent as a nonionic surfactant is selected. A method of internally adding to the polymerization system is also used, but in the case of this method, it is necessary to increase the addition amount in order to improve the tackiness,
Therefore, it affects the polymerization reaction itself, and the surfactants used are limited. In the external addition method in which cutting and crushing are combined as in the present invention, the addition amount can be reduced.

In the case of this external addition method, since the amount of the surfactant added can be reduced, for example, when the polymer is used for sludge treatment, it is possible to suppress the amount of the surfactant flowing out into wastewater after sludge treatment, The impact on will be reduced.

As the surfactant used in the present invention, first, a cationic surfactant having a quaternary ammonium salt as a hydrophilic group, for example, a tetraalkyl quaternary ammonium salt or a trialkylbenzyl quaternary ammonium salt is used. Examples thereof include salts, alkylpyridinium salts and alkylquinolinium salts. An example of these commercially available products is Sanizole B-50 manufactured by Kao Atlas Co., Ltd.

As the nonionic surfactant, as an example of a commercially available product, an alcohol-based antifoaming agent, AF103 manufactured by Toho Chemical Co., Ltd.,
KS502 manufactured by Shin-Etsu Chemical Co., Ltd. can be cited as a silicone antifoaming agent.

These surfactants may be used alone or in an appropriate combination of two or more kinds.

When the amount used is about 0.05%, the effect appears, and when it is 2.0 or more, the effect is not improved and the effect is accumulated in the device, which is not preferable. It is preferably 0.1 to 2.0%.

Hereinafter, the present invention will be described in more detail based on examples, but the following examples do not limit the present invention.

Example 1 10.7 kg of an aqueous solution of quaternary salt of methyl chloride of 80% dimethylaminoethyl methacrylate and 4.3 kg of an aqueous solution of 50% acrylamide were sampled and mixed.

Benzoin ethyl ether 100pp as photopolymerization initiator
m, ethylenediaminetetraacetic acid disodium salt 50 ppm and phosphorous acid 50 ppm were all added to the monomer solution. Bring this monomer solution to 30 ° C and stir it here while stirring.
The pH was adjusted to 4.0 ± 0.1 by adding normal sulfuric acid.

Then, nitrogen replacement is performed for 30 minutes, and the stainless steel plate has a depth of 20 mm.
To form a weir, and attach a polytetrafluoroethylene film to the surface to make a container with a bottom of about 70 cm x 100 cm, pour the above solution into it, and apply polyvinylidene chloride onto polyethylene terephthalate. Covered film (12 + 4μ). From above, a fluorescent chemical lamp manufactured by Mitsubishi Electric Corp. was used at an irradiation intensity of ² W / m ² for 50 minutes, and thereafter, a fluorescent chemical lamp was irradiated at 50 W / m ² for 10 minutes. UVR-1 manufactured by Tokyo Optical Co., Ltd. was used to measure the irradiation intensity. A gel polymer having a thickness of about 20 mm was taken out from the container and divided into four pieces to have a size of about 70 cm × 25 cm. A device with the structure as shown in the figure (KS-340 and BO-257 manufactured by Torai Tekko Co., Ltd.)
From the upper part of the device (combined with 2), each piece was put in, cut, and crushed. At that time, the silicone antifoaming agent (KS502 manufactured by Shin-Etsu Chemical Co., Ltd.) from the nozzle 2 was 0 (comparative), 0.1, 0.2, 0.5, 1.0, 2.0, and 3.0% by weight based on the gel polymer. Sprayed from both sides of the device.

Observe the situation during operation of the device, and also average load current (200V),
The tackiness of the polymer after crushing was measured, and the results are shown in Table 1.

Example 2 2.42 kg of an aqueous quaternary salt of methyl chloride of dimethylaminoethyl methacrylate having a monomer concentration of 80% and 2.58 kg of an aqueous 50% acrylamide solution were collected. Benzoin ethyl ether 100ppm, ethylenediamine 4 as photopolymerization initiator
Both 50 ppm of acetic acid disodium salt and 250 ppm of phosphorous acid were added to the monomer solution. The monomer solution is set to 30 ° C,
The pH was adjusted to 4.5 ± 0.1 with 10 N sulfuric acid with stirring.
After nitrogen substitution for 30 minutes, pour the above solution into a bag of film (12 + 4μ) coated with polyvinylidene chloride on polyethylene terephthalate that is about 30 cm x 70 cm and has a thickness of about 20 mm, and put this in a constant temperature water bath. Stand still so that the upper surface is about 10 mm below the water surface, and the irradiation intensity on the water surface is 3 W from above.
The fluorescent chemical lamp was irradiated for 50 minutes under the condition of / m ² and then for 10 minutes at 60 W / m ² . It was pulled up from the water tank and the gel polymer was taken out from the bag.

It was cut and roughly crushed in the same manner as in Example 1, but at that time, the surfactant and the addition amount were changed. The results shown in Table 2 were obtained.

[Effect of the Invention] The method of the present invention has the following excellent effects.

(1) By supplying a specified surfactant to the polymer, rotary blade, and fixed blade during cutting and crushing, adhesion to the device and mutual adhesion of the polymers can be suppressed, and therefore the device can be operated continuously. It becomes possible to operate for a long time.

(2) Adhesion can be prevented by adding a small amount of surfactant, which is not only economically advantageous, but the amount of surfactant discharged during the treatment such as coagulation and sedimentation is small, which adversely affects the environment and ecosystem. Can be reduced.

[Brief description of drawings]

The figure shows an example of an apparatus used for carrying out the method of the present invention. Sheet Polymer Spray Nozzle Cutting Part Cut Polymer Part Crushing Part Crushing Polymer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideaki Habara 20-1 Miyuki-cho, Otake-shi, Hiroshima Mitsubishi Rayon Co., Ltd. (72) Inventor Nagayuki Takahashi 3 Kaigan-dori, Toyama-shi, Toyama Daiflock Co. Ltd. (72) Inventor Yoji Wada 138 Futtsuka, Noda City, Chiba Prefecture Diaflock Co., Ltd.

Claims (4)

[Claims] 1. A sheet-like polymer surface obtained by polymerizing a water-soluble cationic monomer containing a photopolymerization initiator by irradiation with light in a container having a depth of 50 mm or less, or the polymer. It is characterized in that at least one kind of surfactant selected from the group consisting of a cationic surfactant and a nonionic surfactant is supplied to a cutting blade of a device for cutting the oil while cutting, and subsequently crushed. A method for producing a water-soluble cationic polymer. 2. The water-soluble cationic system according to claim 1, wherein the amount of the surfactant supplied to the surface of the polymer or the cutting blade is 0.1 to 2.0% by weight based on the solid content of the polymer. Polymer production method. 3. The water-soluble cationic system according to claim 1 or 2, wherein the nonionic surfactant supplied to the surface of the polymer or the cutting blade is an alcohol antifoaming agent or a silicon antifoaming agent. Polymer production method. 4. The aqueous solution according to claim 1, wherein the cationic surfactant supplied to the surface of the polymer or the cutting blade has a quaternary ammonium salt as a hydrophilic group in the molecule. Of producing a cationic cationic polymer.