JPS61155405A - Production of acrylic polymer - Google Patents

Abstract

PURPOSE:To obtain granulated acrylic polymer of good water-solubility, by irradiating an aqueous solution of a cationic vinyl monomer with ultraviolt rays in the presence of a nonionic surfactant and a photopolymerization initiator in an atmosphere of an oxygen content of a specified concentration or below and thereby polymerizing the monomer. CONSTITUTION:An acrylic polymer is obtained by polymerizing an aqueous solution of a cationic vinyl monomer or its mixture with other water-soluble vinyl monomers in the following manner. Said aqueous solution is fed to a movable belt and irradiated with ultraviolet rays under conditions including a total monomer concentration in said aqueous monomer solution of 50-80wt%, a pH of 4-7, an amount of a nonionic surfactant of 0.001-1wt% based on monomer, a dissolved oxygen in the monomer solution, of 1mg/1 or below, an amount of a photopolymerization initiator of 0.03wt% or below based on the monomer and an oxygen content in the vapor phase of 1vol% or below. The formed rubber-like layer polymer sheet is continuously withdrawn from the movable belt, crushed, finely pulverized by a vertical cutter and dried with hot air.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an acrylic polymer having good water solubility and having regular particles by irradiating it with light energy.

Acrylic water-soluble polymers, especially water-soluble polymers mainly composed of acrylamide, are used as paper strength agents, thickeners, wastewater purifiers,
Widely used as an ore sedimentation agent. In particular, its use as a flocculant for various industrial wastewaters has been rapidly increasing in recent years as one of the countermeasures against environmental pollution.

When a water-soluble polymer is used as a flocculant, its performance is generally said to be proportional to the molecular weight of the polymer, and there is a tendency for higher molecular weights to be required.

The manufacturing method of the acrylic water-soluble polymer includes bulk polymerization, hanging 7
There are J6 polymerization, emulsion polymerization, (aqueous) solution polymerization, etc., but polymers with a high molecular weight that can be used as a flocculant are most commonly polymerized in an aqueous solution system.

The most common method for obtaining high molecular weight polymers in an aqueous solution system is to use an initiator that generates radicals or a redox initiator consisting of a peroxide and a reducing substance using thermal energy. This is achieved by allowing the polymerization to proceed slowly at high concentrations and at as low a temperature as possible.

Examples of methods for proceeding polymerization without using an initiator that generates radicals by thermal energy include methods using light (ultraviolet rays, visible light) energy, methods using radiation energy, and methods for proceeding polymerization under high pressure. It will be done.

For example, according to Japanese Unexamined Patent Publication No. 46-2094, it is known to produce a water-soluble polymer by subjecting an aqueous solution of an ethylenically unsaturated monomer to radiation polymerization.

However, in polymerization methods that utilize light or radiation energy, the rate of progress of single polymerization is extremely high due to extremely large energy deposits, and as a result, molecular polymerization (grafting) of monomers is promoted. Therefore, the obtained polymer tends to be a so-called water-insoluble polymer rich in three-dimensional network structure.

Moreover, even if a polymer with a small three-dimensional network structure could be obtained, the molecular acid of the polymer would be very small and would not be suitable at all for applications requiring a high molecular weight such as flocculants.

For this major reason, there are currently almost no examples of methods for producing high molecular weight polymers using light or radiation energy being employed on an industrial scale.

However, light or radiation energy can accelerate polymerization very quickly.

For example, monolayer aqueous solutions usually contain polymerization inhibitors and are kept in a liquid state, but if they are contained in a considerable amount, they will not polymerize easily when exposed to thermal energy, but when irradiated with light energy they will polymerize very quickly. It causes a polymerization reaction over time.

Particularly in the field of light energy, in view of the fact that in recent years it has become possible to obtain such equipment at low cost and at will, its effective use is highly desirable from an industrial perspective.

It also has several characteristics compared to conventional polymerization methods that utilize thermal energy. In other words, since the polymerization rate is extremely high, the polymerization time is greatly shortened and productivity is improved, and the reaction rate of the monomer is greatly increased, so the current situation is that the toxicity of the monomer is being raised. From this point of view, it has advantages such as being easy to lead to non-pollution, and being very compact in terms of equipment because continuous and short-time reactions are possible.

Therefore, if we can improve the polymerization technology using light energy irradiation, suppress or prevent the formation of the three-dimensional network structure, and develop a technology that can increase the molecular weight, it will greatly contribute to industrial progress.

As a result of intensive research into polymerization by irradiation with light energy, the present inventors have not only succeeded in elucidating these problems, but have also reached the point where the polymerization technology can be fully adopted industrially. It was confirmed that the polymerization mechanisms of irradiation polymerization and heat-initiated polymerization are completely different, and that favorable factors for heat-initiated polymerization are not necessarily favorable factors for light energy irradiation polymerization.As a result of various technological development efforts, 1. the present invention. has been reached. That is, the present invention provides a method for producing a water-soluble polymer by polymerizing an aqueous solution consisting of a cationic vinyl monomer alone or a mixture with other water-soluble vinyl monomers, comprising: (a) monomer; The total amount of monomers in the monomer aqueous solution is 50 to 80 wt%.
, and the pH is adjusted to 4 to 7, (b) 0.001 to 1 wt% (based on the monomer) of one or more nonionic surfactants are added to the monomer aqueous solution, and (C ) After reducing the dissolved oxygen in the monomer aqueous solution to 1 mg/l or less.

(d) 0°03wt of photopolymerization initiator in monomer aqueous solution
% or less/monomer is added and mixed uniformly, (e) After that, the above (a) to (d) are placed on a movable belt in an atmosphere where oxygen in the gas phase is lvo 1% or less.
(f) Supply the monomer aqueous solution prepared in step 3 to a thickness of 3 to 10 mm;
00 to 450 mg, irradiated with ultraviolet light of 50 W/rrf or less for 30 to 90 minutes, (g) Then, the rubbery layer polymer sheet with a thickness of 3 to 10 mm was continuously taken out from the movable belt, (h) This rubber-like layer polymer sheet is crushed into square pieces of 3 to 10 mm with a roller type cutter while maintaining the polymer concentration at 50 to 85 wt%; %
(j) Drying with hot air. The present invention provides a method for producing an acrylic polymer with good water solubility and well-sized particles.

The cationic monomer used in the present invention has the general formula % formula % (1) [wherein R1: hydrogen atom, methyl group, R2-R4
: y-o-1 or -N, which represents an alkyl group, hydroxylalkyl group, or aralkyl group having 1 to 4 carbon atoms.
H-1n: an integer of 1 to 4, xO: acid residue (...rogen,
Examples of the compounds represented by the following formulas include β-7 chloroyloxyethyltrimethylammonium salt (chloride, sulfate, etc.), β-methacryloyloxyethyltrimethylammonium salt, Methacryloyloxyethyldimethylaminate (hydrochloride, acetate, sulfate), (
N,N-dithimelamino n-propyl)acrylamide.

(N,N-dimethylaminoethyl)acrylamide, water-soluble salts of methacrylamide, and the like.

Other monomers used in this application include acrylamide, methacrylamide and their derivatives, acrylic acid, methacrylic acid and their alkali metal salts, amine salts, acrylamide-2-methylpropanesulfonic acid and its salts, vinyl Includes sulfonic acids and their salts. Furthermore, other monomers such as esters of (meth)acrylic acid such as alkyl esters of (meth)acrylic acid, hydroxyalkyl esters, and aminoalkyl esters,
Even hydrophobic monomers such as acronitrile, styrene, chlorostyrene, vinyl acetate, etc. can be optionally added as long as the resulting polymer is water-soluble.

The concentration of the monomer aqueous solution used for polymerization is 50 to 80 wt.
,% is preferable, and the pH of the monomer aqueous solution is 4 to 7.
is within the range of As the monomer concentration increases, three-dimensional network reactions are more likely to occur as side effects, and polymers that are completely water-soluble generally have a lower degree of polymerization. However, if the techniques described in this application are utilized and the combinations are carried out, a high molecular weight polymer that maintains water solubility to the extent that it can be used as a flocculant can be obtained.

During polymerization, the most preferable monomer concentration is 60 to 7, in order to maintain the quality of the polymer at a high level and to obtain the obtained polymer in powder form from an aqueous solution.
Most preferably, it is maintained at 0 wt.%.

In the present invention, by adding a surfactant, a decrease in water solubility due to crosslinking reaction of the resulting polymer is prevented, that is, the formation of a water-insoluble polymer, which has a high molecular weight and good water solubility. A polymer can be obtained. In addition, the polymer can be easily taken out from the polymerization container, the stickiness characteristic of polymers can be prevented, and mutual adhesion of polymers can be prevented.

As a surfactant, polyethylene glycol 7)L
The amount of surfactants to be blended includes nonionic surfactants such as t-kylphenyl ether (especially polyethylene glycol distyrenated phenyl ether) polyethylene glycol alkyl ether, polyethylene glycol fatty acid ester, polyethylene glycol sorbitan fatty acid ester, etc. , 0.001-1wt% (based on monomer).If it is less than 0.001%, the intended purpose will not be achieved, and if it exceeds 1wt%, the surfactant will exhibit a chain transfer effect. Therefore, the molecular weight of the obtained polymer becomes significantly low, making it impossible to obtain a high molecular weight polymer as the object of the present application.

Further, examples of the hypophosphite that can be used in combination with the above surfactant and one or more of hypophosphites, urea compounds, and aliphatic tertiary amines include sodium hypophosphite, Examples of aliphatic tertiary amines include potassium hypophosphite and ammonium hypophosphite salts, and may also be amine salts of hypophosphite produced by hypophosphorous acid and tertiary amines. , dimethylethylamine, methyldiethylamine, triethanolamine, methylgetanolamine, dimethylethanolamine, ethylgetanolamine, etc. Urea compounds include urea, thiourea, ethyleneurea, ethylenethiourea, guanidine salts, etc. There is.

By blending hypophosphites, aliphatic tertiary amines, and urea compounds, similar to surfactants, the water solubility of the obtained polymer can be improved, that is, the crosslinking reaction in the polymerization reaction can be prevented, and the obtained polymer can be improved. It is possible to prevent cross-linking reactions in intermolecular and intramolecular bonds during the step of crushing and drying the resulting polymer gel.

Although good results can be obtained by adding a surfactant alone, 1
By using hypophosphites, aliphatic tertiary amines, or urea compounds in combination, even more excellent effects can be achieved.

Next, regarding the blending amount, hypophosphite is o, ooi to 5.0% based on the total amount of monomers. Owt.% is more preferable, and the amount of aliphatic tertiary amine and urea compound is also 0.001 to 5.0% based on the total amount of monomers. Owt,
% is a more preferable range.

The combination of surfactant and hypophosphite, aliphatic tertiary amine, or urea compound can be selected arbitrarily.

During the polymerization stage, the amount of dissolved oxygen in the monomer aqueous solution and the amount of gas phase oxygen in the polymerization atmosphere have extremely important effects on the polymerization reaction, so they must be kept as low as possible in the evening.

Methods for removing oxygen include 1, for example, nitrogen gas, carbon dioxide gas, etc.
Known methods such as introducing an inert gas such as tc into the monomer aqueous solution or sealing it into the polymerization gas phase chamber can be employed.

The amount of dissolved oxygen in the monomer aqueous solution must be limited to 1 mg/l or less prior to the polymerization reaction. If it exceeds this range, undesirable results such as generation of unpolymerized portions and failure to improve the degree of polymerization will occur.

The amount of oxygen in the gas phase is also the same as the above reason, and 1
vol. % or less.

The ultraviolet light used for polymerization is commonly available.

In addition to xenon lamps, tungsten lamps, halogen lamps, and carbon arc lamps, high-pressure mercury lamps and low-pressure mercury lamps are used. The wavelength used for one polymerization is most preferably 300 mIL to 450 mIL.

As the photopolymerization initiator, commonly used ones, 4f4
Lt! Any of benzophenone, benzoin, benzoin alkyl ether, and monochromatic azo compounds may be used, but from the viewpoint of polymerization rate, benzoin alkyl ether is preferable.

The photopolymerization initiator is used by adding 0.03 wt 0% or less/monomer to an aqueous monomer solution and mixing uniformly. o, o
Amounts greater than 3% by weight can be used, but the high molecular weight polymers targeted by the present application will not be obtained.

Although the polymerization method can be produced either batchwise or continuously, in the sense of improving production efficiency, it is preferable to carry out the polymerization continuously on a movable plate, for example. Although it can be produced in the form of droplets or blocks, it is more preferable to supply it in the form of a thin layer, that is, with a film thickness of 3 to 10 mm, and polymerize it.

Preferably, the polymerization mode in the production method of the present invention can be efficiently polymerized by cooling with water or cold water in order to completely remove the reaction heat.

Generally, the higher the light intensity, the faster the polymerization reaction, but the lower the molecular weight of the resulting polymer. Moreover, since the light irradiation time during polymerization has a close relationship with the light intensity of ultraviolet light, it is necessary to adjust the ultraviolet light intensity and the irradiation time as appropriate depending on the degree of polymerization of the desired polymer.

Therefore, in order to obtain the high molecular weight polymer of the present application, the intensity of ultraviolet rays and the irradiation time must be carefully considered and set.

The intensity of ultraviolet rays on the surface of the polymerization container is set to 50 W/m2 or less, preferably 15 to 30 W/m2. The irradiation time at this time is 30 to 90 minutes, preferably 30 to 60 minutes.

The polymer gel obtained by polymerization under the above polymerization conditions is removed from the polymerization vessel.

The obtained polymer is substantially a highly sticky polymer, but in this application, a surfactant is used to prevent stickiness, so taking it out from the polymerization container is easy.
It can be peeled off and taken out very easily.

Particularly when polymerization is carried out using a movable belt, continuous peeling and extraction becomes possible.

In the present application, by coating the movable belt with the tetrafluoroethylene-ethylene copolymer, the generated polymer can be extremely easily peeled off and taken out from the movable belt.

In addition, the movable belt is coated with tetrafluoroethylene-ethylene copolymer, and even more! By depositing metal on one side, ultraviolet rays can be irradiated more efficiently and the polymerization reaction can be promoted.

When acrylamide or a monomer solution mainly composed of acrylamide is polymerized at the above-mentioned concentration, a hard or highly elastic gel-like material having no fluidity is obtained. Therefore, for example, if you try to volatilize the water contained in a mass or sheet of gel polymer without mechanically crushing it, you will have to leave it under high temperature for a very long time. Inevitably, as a result, the molecular weight of the high-molecular-weight polymer obtained is reduced, and crosslinking of the polymer due to thermal changes is promoted, resulting in a significant decrease in commercial value.

Therefore, the resulting polymer gel mass or sheet is generally processed by some mechanical means.

A method is adopted in which the particles are coarsely crushed into small agglomerates and then dried by heating to remove water.

Generally, a method is widely adopted in which a polymer gel obtained by polymerization is formed into a strand shape using an extrusion molding machine such as a meat grinder, and then heated and dried. However, when using an extrusion molding machine such as a meat grinder, especially if the polymer gel is extremely hard, the friction on the machine wall is large, causing a loss of machine efficiency, and the polymer gel itself is subject to friction. This is not a very preferable method because it is subject to deterioration due to heat and physical forces, resulting in a decrease in molecular weight due to molecular cleavage.

The present invention also provides a manufacturing method for obtaining a fine-grained polymer gel without deteriorating the polymer gel itself due to frictional heat, physical force, etc., and without causing a decrease in molecular weight due to molecular cutting, etc. It is something.

The form of the polymer gel can be determined, for example, from the top of the crushing machine described in the patent application filed on November 6, 1980 (invention title ``Method for crushing water-soluble polymer gel J'' hereinafter referred to as A application). The supplied polymer gel is cut into strip-shaped strands by a pair of roller-type cutters rotating in mutually interlocking directions. When feeding is carried out continuously using a method such as taking out the polymer gel continuously from the other end of a movable support, such as an endless belt, and inserting it into a roller-type cutter,
Processes can be made continuous and production efficiency can be improved. A polymer strand cut, for example, into strips by a pair of roller-type cutters rotating in an interlocking direction, is cut by a rotating blade and a fixed blade provided on the outer periphery of the rotating body, and is then cut into strips, preferably into strips. It is made into rectangular strips with an average particle diameter of 3 to 10 mm.

The polymer concentration at this time is maintained at 50-85 wt.%.

If it is lower than this range, it will be difficult to crush it into a predetermined square shape, and if it is higher than this range, the polymer gel will become extremely hard and the mechanical load will be large, making it difficult to crush it continuously. It becomes impossible. Further, in order to maintain water solubility and furthermore to prevent a decrease in molecular weight, it is necessary to maintain it within this range.

The thus obtained 3-10 mm square polymer gel was
Rigid cutting machine 1 For example, the device described in the patent application filed on November 6, 1980 (title of invention "Method for refining water-soluble polymer gel 1 hereinafter referred to as B application") The particles are refined to a diameter of 0.3 to 3 mm while maintaining a polymer content of 50 to 85 wt.%.

The structure of the cutting machine is characterized by adjusting the gap between the vertical fixed blade and the rotary blade installed vertically inside the cutting machine;
By changing the sieve hole diameter and by arranging multiple rigid cutting machines in series, that is, by changing the cutting machines into two
By passing the material several times, it becomes possible to control the residence time of the grinding, and it becomes easy to cut the polymer gel into small particle diameters, for example, 1 mmφ or less. Another point is that the shape of the polymer gel having a small particle size, such as 1 mmφ or less, has a favorable effect of approaching a sphere. A technique for refining crushed polymer gel using a rigid cutting machine having such a structure has not been established in the past.

For example, in the first step, cutting is performed using a cutting machine equipped with a 3 mm φ screen, and a finely divided polymer gel having a uniform particle diameter of about 3 mm φ or less can be obtained. Then, in the second step, the particles are refined using a cutting machine equipped with a 2 mmφ screen, and in the third step, the particles are refined using a cutting machine equipped with a 1 mmφ screen.
The fine particles are unified to about 1 mmφ or less and have a rounded shape. By selecting a screen suitable for the target particle size in this manner, the target particle size can be obtained.

In addition, when the method of the present invention is adopted, in the step of refining the polymer gel, which is essentially in a wet state, by maintaining the polymer concentration at 30 to 60 wt.%, almost no dust is generated. It is possible to obtain particles with a uniform particle size, so to speak, a particle size distribution close to monodisperse. Therefore, the normally employed process, that is, the step of drying the polymer gel, then pulverizing it and sizing it, becomes unnecessary.

One of the features of the present invention is that a method is adopted in which a polymer gel containing a large amount of water is made into fine particles as it is,
By employing this method, a high molecular weight acrylic polymer with good water solubility and sized particles can be obtained for the first time.

In order to increase the cutting efficiency when crushing a polymer gel and make it into fine particles, and to prevent the obtained fragmented polymer gel and the further fine-grained polymer gel from re-adhering. It is preferable to keep the temperature of the polymer gel as low as possible during cutting.

Methods for lowering the temperature of the polymer gel include, when crushing it into small pieces, cooling it sufficiently during the polymerization stage, and cooling the polymer gel obtained by polymerization by blowing cold air etc. before crushing it in a crusher. This can be achieved by forced cooling, usually 10-30°C, preferably 2°C.
It is preferable to adjust the temperature to 0°C or lower.

In addition, in the crushing and pulverization process, if necessary, polyethylene glycol, nonionic surfactant, anionic surfactant, etc. may be added to the crusher or vertical cutting machine.
It may be applied to the surface of the polymer gel or the surface of the crushed polymer gel to prevent re-adhesion of the fragmented polymer gel or finely granulated polymer gel.

The finely granulated polymer gel is usually dried by a known method, for example, with hot air on a ventilated heald, and is obtained as a granular material having a moisture content of 10 wt.% or less.

In the production method of the present application, as described above, it is not necessary to further crush or size the powder or granules, but it is also possible to adopt a crushing and size size process if necessary.

The molecular weight of the obtained polymer is such that it has a very high intrinsic viscosity;
For example, an acrylic polymer having an intrinsic viscosity of [113 or more, preferably 4 to 15], good water solubility, and sized particles can be obtained.

Next, one embodiment of the present invention will be specifically explained using examples.

Example 1 A tetrafluorinated ethylene-ethylene copolymer film deposited with 1gmft<aluminum was attached to an endless belt made of stainless steel with an rtl of 450 mm and an effective length of 3°OOmm, and heated to cold water from below. A movable support for polymerization having a structure that allows it to be sprayed onto the endless belt is installed in a room completely filled with nitrogen gas and where the amount of oxygen in the gas phase is 1 vot, % or less.
Tit# was applied at a constant speed of 00 mm/min, and water at 15° C. was sprayed from below the belt. Furthermore, a low-pressure mercury lamp was installed as an ultraviolet irradiation source above the movable support, and the intensity of ultraviolet rays was set to 30 W/m 2 .

Next, β-methacryloyloxyethyltrimethylammonyram chloride (80% product) 37.500 g polyoxydiethylene distyrenated phenyl ether (HLB12) 15 g (0.0
5%) Sodium hypophosphite 3g (o,
o i%) was measured, deionized water was added so that the total amount was 40.000 g, the pH was adjusted to 5, and an aqueous monomer solution was prepared.

Approximately 40 liters of this aqueous monomer solution was sufficiently degassed with nitrogen gas to have dissolved oxygen of 1 mg/l or less, and was quantitatively fed onto the belt in operation at a rate of 13.51/hour from one end of the belt.

In addition, a temporary storage tank with an agitator installed above the belt (5
1 volume), a 5% methanol solution of benzoin isopropyl ether as a polymerization initiator was fed into the monomer aqueous solution at a rate of 30 ml/hour, and polymerization by ultraviolet irradiation was carried out while uniformly mixing the monomer aqueous solution and the photopolymerization initiator. went.

Under the above conditions, the time during which the aqueous monomer solution was subjected to polymerization on the belt was 30 minutes, and the layer of the aqueous monomer solution during one polymerization was about 5 mm.

Thirty minutes after the start of supplying the monomer aqueous solution, a sheet-like polymer having a thickness of 5 mm was obtained from the other end of the endless belt. The obtained polymer could be easily peeled off from the belt surface by hand, and continuous polymerization for about 3 hours was possible. The temperature of the obtained polymer gel was 20°C. The polymer gel sheet continuously obtained from the other end of the endless belt is fed to the crusher exemplified in the specification of the A application, and 3X5X
A 5 mm square polymer gel was obtained.

Next, while blowing cold air at about 15° C., the particles were finely divided using a vertical cutter as shown in the B application specification equipped with a screen of about 3 mmφ, and then cut with a screen of about 2 mmφ and a screen of about 1 mmφ set. The polymer gel was passed through a machine in this order and cut to obtain a finely divided polymer gel having a size of approximately immmφ.

The resulting finely granulated polymer gel having a diameter of about 1 mm was dried at 80°C in a ventilation band dryer.
It took about 13 minutes to change the powder to a moisture content of 10% or less.

The obtained powder is sized to approximately 0.9 mmφ,
The aqueous solution does not contain any water-insoluble substances and has an intrinsic viscosity of 7.
It was 8 dl/g.

Claims (1)

[Claims] 1. A method for producing a water-soluble polymer by polymerizing an aqueous solution consisting of a cationic vinyl monomer alone or a mixture with other water-soluble vinyl monomers, comprising: (a) ) The total amount of monomers in the monomer aqueous solution is 50 to 80 wt%.
, and the pH is adjusted to 4 to 7, (b) 0.00 to 1 wt% (based on the monomer) of one or more nonionic surfactants are added to the monomer aqueous solution, and ( c) Reduce the dissolved oxygen in the monomer aqueous solution to 1 mg/l or less, and then (d) Add 0.03 wt of photopolymerization initiator to the monomer aqueous solution.
% or less/monomer, add and mix uniformly, (e) Then, on a movable belt in an atmosphere where oxygen in the gas phase is 1 vol% or less, the monomer prepared in (a) to (d) above is added. Supplying the aqueous solution to a thickness of 3 to 10 mm, (f) supplying the monomer aqueous solution on the movable belt with
00~450mμ, 50W/m^2 or less ultraviolet rays 30
irradiating for ~90 minutes; (g) then successively removing 3-10 mm thick rubbery layered polymer sheets from the movable belt; (h) irradiating such rubbery layered polymer sheets with a polymer concentration of 50 mm; While maintaining the polymer concentration at ~85 wt%, crush it into 3-10 mm squares with a roller cutter, (i) Then, similarly reduce the polymer concentration to 50-85 wt%.
A method for producing a granulated acrylic polymer with good water solubility, which comprises: (j) drying with hot air; 2. The above-mentioned cationic vinyl monomer has a general formula ▲ There are numerical formulas, chemical formulas, tables, etc. ▼... (1) [However, in the formula, R_1: hydrogen atom, methyl group, R_2 ~
R_4: represents an alkyl group, hydroxylalkyl group, or aralkyl group having 1 to 4 carbon atoms. Y:-O-,
or -NH-, n: an integer of 1 to 4, X^■: acid residue (representing halogen, alkyl sulfate, phosphoric acid, acetate ion)], the other water-soluble vinyl monomers mentioned above is one or two selected from acrylamide, acrylonitrile, and hydroxyethyl (meth)acrylate.
The manufacturing method according to claim 1, wherein the method is one or more species. 3. The nonionic surfactant is one or two selected from polyethylene glycol alkyl phenyl ether (especially polyethylene glycol distyrenated phenyl ether), polyethylene glycol alkyl ether, polyethylene glycol fatty acid ester, and polyethylene glycol sorbitan ester. The manufacturing method according to claim 1, which is the above. 4. The manufacturing method according to claim 1, wherein one or more of hypophosphites, aliphatic tertiary amines, and urea compounds are used in combination. 5. The method according to claim 1, wherein the photopolymerization initiator is one or more selected from benzoin, benzoin alkyl ether, benzyl, benzophenone, and anthraquinone. . 6. The manufacturing method according to claim 1, wherein the movable belt is coated with a tetrafluoroethylene-ethylene copolymer and further has a back surface coated with metal vapor deposition. 7. The manufacturing method according to claim 1, wherein the irradiation intensity is 15 to 30 W/m^2 and the irradiation time is 30 to 60 minutes. 8. The manufacturing method according to claim 1, wherein the lower part of the movable belt is cooled with water or cold water during irradiation. 9. The manufacturing method according to claim 1, wherein the rubber-like layer polymer sheet taken out from the movable belt is left under hot air at 50 to 120° C. for 5 minutes or less to modify the surface of the sheet. 10. The manufacturing method according to claim 1, wherein the surface of the rubber-like layer polymer sheet is coated with a nonionic surfactant, polyethylene glycol, or an aqueous solution thereof. 11. The manufacturing method according to claim 1, wherein cold air is blown into the vertical cutting machine. 12. The manufacturing method according to claim 1, wherein the water-soluble and sized acrylic polymer has an intrinsic viscosity [η] of 4 to 15.