JPH0362827A - Production of uniform polymer granule - Google Patents

Abstract

PURPOSE:To stably obtain the title fine granules for use as adsorbents, etc., without generating any noise by jetting a polymer-contg. solution of specified viscosity through a nozzle set in a dispersion medium toward an electrode equipped nearby while applying an alternate current voltage of constant period and by coagulating the resultant granule produced. CONSTITUTION:A solution containing a polymer for forming granules and <=50 cps in viscosity is introduced through an inlet 3 of a nozzle 2 set in a dispersion medium put into a dispersion tank 10 of a dispersion unit 1, and jetted through the nozzle 2 while applying an alternate current voltage of constant period, using an alternate current source 7, between the nozzle 2 and an electrode 8 equipped nearby said nozzle 2 in the medium, effecting formation, in the dispersion medium, of droplets of a number synchronous with the period of the alternate current voltage, followed by, in a moving tank 11, vaporizing the solvent in the droplets by a heating device 12, gelling through cooling, or adding a gelling accelerator to the dispersion to coagulate the droplets, thus obtaining the objective polymer granules.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the production of polymer particles having a uniform particle size (hereinafter referred to as uniform polymer particles) that can be used as adsorbents, chromatography fillers, and the like.

[Prior art] This method takes advantage of the fact that when a limb is ejected from a nozzle into a gas or dispersion medium while applying mechanical vibration at a constant period, a uniform number of droplets are formed in synchronization with the vibration frequency. , uniform polymer particles have traditionally been produced.

In this method, the frequency at which uniform droplets are formed is lfk
It is determined by the viscosity of the body, surface tension, nozzle diameter, jet flow velocity, vibration amplitude, etc., and has a value within a specific range. Generally, in order to reduce the droplet diameter, it is necessary to increase the vibration frequency, but in order to achieve a synchronized state, it is necessary to reduce the nozzle diameter and increase the ejection flow velocity.

For example, JP-A-57-102095 discloses that a polymerizable monomer is ejected into a liquid dispersion medium while applying mechanical vibration to form uniform droplets, and then polymerized to produce uniform polymer particles. Are listed. However, as described above, if small droplets are to be produced, the ejection flow velocity must be increased, but if the ejection flow velocity is increased unnecessarily, the ejection flow will be broken by friction with the dispersion medium. Therefore, this method can be applied to hanging particles having a particle size of about 500 coral or more.

In order to produce even smaller particles, JP-A-Sho [1l-8
Publication No. 3202 describes that a polymerizable monomer is ejected into a gas while applying mechanical vibration to form droplets, and then polymerized. However, as the droplet diameter becomes smaller, the droplet becomes suspended in the gas for a longer period of time, and a large number of droplets are generated that collide with later ejected droplets and coalesce. Therefore, the polymer particles produced by this method contain many particles of large particle size. In addition, floating droplets adhere to nozzles and the like, interfering with stable production.

As described in Japanese Unexamined Patent Publication No. 03-117039, the present inventors applied constant mechanical vibration to a polymer solution to which a DC voltage was applied, and formed droplets with the same electric charge into the gas. A method has already been found to produce uniform polymer particles by ejecting and then penetrating into a coagulation liquid.

However, even with this method, it has been found that if the droplets become small, they may remain suspended in the gas for a long time and adhere to the nozzle or electrode, interfering with stable production.

[Problems to be Solved by the Invention] As mentioned above, in order to produce uniform polymer particles with a small particle size using the conventional technology, it is necessary to first form minute droplets of a liquid that will become a precursor in a gas. However, such droplets remain ff- in the gas for a long time, causing the formation of a large number of combined droplets, or adhering to nozzles and electrodes, which hinders stable production.

Further, in the conventional technology, mechanical vibration is used as a vibration source, but this generates a large amount of noise, so special soundproofing measures are required.

Furthermore, vibrating parts generally have a mechanically tuned structure, and are sensitive to changes in load and temperature, making it extremely difficult to maintain a constant frequency for long periods of time.

Naturally, if the vibration frequency changes, the particle size will also change.

These problems can be solved if uniform droplets, which are precursors of polymer particles, can be formed directly in the dispersion medium using a more stable vibration source than is mechanical.

By the way, a constant periodic alternating current voltage is applied between the nozzle, which is placed in a second liquid that does not dissolve the first liquid, and the nozzle and an electrode provided in the second limb near the nozzle. It has already been reported in Japanese Patent Application Laid-Open No. 5817 (1983) that when ejecting water while adding water, droplets of the first limb are formed in synchronization with the period.
5 [Described in i 68 publication. However, no one has attempted to utilize this technique for the production of uniform polymer particles. The above-mentioned publication does not suggest such a method of use at all, and the characteristics that the first liquid and the second liquid should have, the aperture of the nozzle, the ejection speed of the first liquid, these characteristics and the AC voltage are not discussed at all. There is no sufficient description of the relationship between the period and the period, and it is completely unpredictable whether this method can actually be applied to the production of uniform polymer particles.

The present inventor reconsidered whether this method could be applied to the production of polymer particles, and as a result of further studies, the present invention was achieved.

[Means for Solving the Problems] The present invention provides the following methods: A solution containing a particle-forming polymer substance having a viscosity of 50 cps or less is introduced into a dispersion medium near the nozzle through a nozzle installed in a dispersion medium of this solution. By ejecting while applying a constant alternating current voltage between the electrode and the nozzle,
After generating droplets of the solution in the dispersion medium in a number synchronized with the cycle of the alternating current voltage, the solvent in the droplets is volatilized by heating, gelled by cooling, or gelled by the dispersion wave. A method for producing uniform polymer particles characterized in that the droplets are solidified by adding an accelerator, and a vinyl polymerizable monomer liquid having a viscosity of 50 cps or less is passed through a nozzle installed in a dispersion medium of this liquid. A number of droplets of the liquid synchronized with the cycle of the AC voltage are generated in the dispersion medium by ejecting the liquid while applying a constant cycle of AC voltage between an electrode provided in the dispersion medium in the vicinity and the nozzle. The present invention relates to a method for producing uniform polymer particles, which is characterized in that the particles are then polymerized.

[Example] First, the first method for producing uniform polymer particles of the present invention will be specifically described.

The first manufacturing method uses a solution containing a particle-forming polymeric substance.

Generally, any solvent-soluble polymer can be used as this polymeric substance, so it is sufficient to select one suitable for the purpose of use.

The polymeric substance may be a natural polymeric substance or a synthetic polymeric substance.

Specific examples of the natural polymer substances include natural polymer substances and derivatives thereof such as cellulose, agarose, carrageenan, alginate, silk buproin, collagen, and chitin, and particles produced from these substances have excellent properties. It is useful as a functional adsorbent or carrier.

Examples of the synthetic polymer substances include polyvinyl alcohol, poly-γ-methyl-L-glutamate, methyl methacrylate/hydroxyethyl methacrylate copolymer, and these are also suitable as functional adsorbents and carriers. becomes a particle. Furthermore, polymers into which crosslinked structures and ion exchange groups can be introduced, such as styrene/butadiene copolymers and styrene/chloromethylated styrene copolymers, are also useful as base materials for ion exchange resins.

These polymeric substances are used in the present invention after being dissolved in a hydrophobic or hydrophilic solvent. A liquid that is incompatible or poorly compatible with the dispersion medium described below is selected as the solvent.

Solvents for natural polymer substances and their derivatives are described in "Natural Polymer J (198
4) Kyoritsu Shuppan■ and Samuel M. Hudson (Sa.
iuel M, Hudson), John A, Cuculo, Journal of Macromolecular Science Reviews in Macromolecular Chemistry and Physics.
cular Science-Reviews jnM
acromolecular CheIllistr
y and Physics) J (1980) C18 [
1), 1 to 82, and so on. In addition, the solvent for synthetic polymer substances is J Brand Wrap (
J. Brandrup), “Polymer Handbook Second Edition”
OK, 2nd edition) J (1975),
John Wiley and Sons Inc.
, ), etc., can be used as a reference.

As specific examples of the solvent, hydrophobic solvents such as chlorinated hydrocarbons such as methylene chloride, chloroform, dichloroethane, and trichloroethane are commonly used singly or in combination of two or more. A small amount of lower alcohol such as methanol or ethanol can be added to these solvents as a coagulation accelerator. Furthermore, an aliphatic alcohol having 4 to 12 carbon atoms can be added to make the polymer particles porous. Examples of hydrophilic solvents include aqueous solution, acetone, tetrahydrofuran, dioxane, dimethylformamide, dimethylacetamide,
Water-soluble solvents such as dimethyl sulfoxide and N-methyl-2-pyrrolidone are commonly used. Water-soluble lower alcohols, water-soluble polyhydric alcohols, inorganic salts, etc. can also be added to these to promote coagulation or to make the polymer particles porous.

The viscosity of the solution containing the particle-forming polymer substance is 30°C.
is 50 cps or less, preferably 20 cps or less.

When the viscosity is greater than 50 cps, it is difficult to form droplets that are synchronized with the alternating current cycle. Further, there is no particular restriction on the electrical conductivity of this solution.

In the present invention, droplets are formed by ejecting a solution containing the particle-forming polymeric substance from a nozzle into a dispersion medium that is incompatible or poorly compatible with the solution, as described below.

The dispersion medium is O when the solvent for the polymeric substance is hydrophobic.
/W type dispersion by adding a nonionic surfactant such as gelatin, methylcellulose, polyvinyl alcohol, polyoxyethylene sorbitan monolaurate, polyoxyethylene lauryl ether, polyethylene glycol monostearate, etc. An aqueous solution containing ~5% (by weight, hereinafter the same) is usually used. Conversely, when the solvent for the polymeric substance is hydrophilic, a hydrophobic organic liquid is used as the dispersion medium. Specific examples of organic liquids include hydrocarbon liquids such as liquid paraffin, ligroin, and tetralin, cultivated oils such as rapeseed oil and cottonseed oil, and halogenated carbonates such as carbon tetrachloride and 1,1,2,2-tetrachloroethane. A hydrogen-based solvent or the like is used. III, B (t(hydrophilic-Lip
surfactants containing 3 to 7 surfactants, such as glycerol monostearate, glycerol monooleate, sorbitan mono Oleate 4 and the like are added in an amount of about 0.5 to 5%.

The smaller the viscosity of the dispersion medium, the lower the viscosity is, and the viscosity is 50 cp at 30°C.
s or less, more preferably 20 cps or less, particularly preferably 5 cps or less. When the viscosity increases, when the limb is ejected from the nozzle at a high flow rate, the jet stream is destroyed by viscous resistance, making it difficult to form uniform droplets.

2 The electrical conductivity of the dispersion medium is IQ-10 to 10 μslam,
More preferably, it is 10-7 to 10-0 μs/cm. Further, it is preferable that the dielectric constant is large. If the electrical conductivity is too high or too low, uniform droplets tend to be difficult to form. The reason for this is not fully understood, but it is probably because if the electrical conductivity is too high, the electric charge of the liquid in the nozzle just before it becomes a droplet is immediately neutralized, and no single force acts between the electrode and the liquid. I think that the. Also, if the electrical conductivity and dielectric constant are small, a large amount of charge will not be induced in the dispersion medium around the nozzle, and a large repulsive force will not work between it and the liquid of the same sign at the nozzle opening. I think that the.

The jetting is performed by jetting a solution containing a particle-forming polymer substance from a nozzle placed in a dispersion medium while applying a constant alternating current voltage between the nozzle and an electrode placed in the dispersion medium near the nozzle. It is done in this way.

In the present invention, since ejection is performed in a dispersion medium in this way, the droplets may coalesce with later ejected droplets and become larger in size, or the droplets may not reach the nozzle or Almost no adhesion to the electrodes occurs. In addition, since the droplets are formed by the cycle of AC voltage and are not dependent on mechanical vibrations, the droplet size can be reduced without increasing the ejection flow rate, there is no noise problem, and the cycle is stable. Because of this, the particle size of the droplets becomes constant.

Next, a method of forming droplets by the jetting will be explained based on FIG. 1.

FIG. 1 is a partially sectional view showing an example of a hanging device used in the present invention. In the dispersion device (1) shown in Fig. 1, a solution of a polymeric substance to be formed into droplets is ejected at a constant flow rate from the inlet (3) of the nozzle (2) into the dispersion tank 00 as shown by the arrow. It will be done.

The nozzle (2) is generally made of metal, and as shown in the figure, the part (4) that comes into contact with the dispersion medium is covered with an electrically insulating coating except for the needle-like tip. Although the apparatus shown in FIG. 1 uses a single-hole nozzle as shown in FIG. 2 (enlarged cross-sectional view of the nozzle tip), it is of course possible to use a multi-hole nozzle. In addition, the diameter of the liquid ejection port 041 of the nozzle is normally 20 to 250μ, but in order to produce droplets with a relatively small particle size of 250um or less, the diameter is preferably 200μ or less, and in order to avoid clogging of the nozzle. is 402
/m or more is preferable.

The dispersion medium is fed into the dispersion tank 00 from the population (5) through the current plate (6) made of an electrical insulator as shown by the arrow. (
8) is an electrode, which is made of metal such as stainless steel and has a ring shape with an inner diameter of about 10 to 20 mm,
The nozzle (2) is placed near the nozzle (2), preferably at a position approximately 10 to 50 fflffI away from the tip of the nozzle (2).
2) The ring is installed so that a solution of a polymer substance ejected from the ring passes through the ring. The lead wire from the electrode (8) is taken out from the wall of the dispersion tank via the outlet (9) in an electrically insulating manner, and is connected to the AC power source (7). The other end of the lead wire from the AC power source (the other end of the lead wire from the sword is connected to the nozzle (2). The moving tank 01) is equipped with a jacket 02) for adjusting the temperature of the dispersion liquid.

5. The discharge amount of the solution containing the polymeric substance from the nozzle (2) is preferably in the range of 10 to 100[1], more preferably 20 to 500 when converted to Reynolds number. When the Reynolds number is less than 1O, the amount of droplets produced decreases, while when it exceeds 1000, the AC voltage and period that reach the synchronized state exceed several kV and 10kllz, and it tends to be difficult to maintain a stable state. .

The voltage and period of the alternating current are preferably several kV and 10 kHz or less, respectively. However, since the voltage and period at which the synchronization state can be changed cannot be set independently, there are usually 3
It is set proportionally in the range of 00 to 5000V and 500 to 10000Hz.

The flow rate of the dispersion medium is preferably such that the concentration of droplets in the dispersion liquid is 5% by volume or less, more preferably 3% by volume or less. By flowing the dispersion medium at such a flow rate, the droplets can be washed away by the dispersion medium without causing the droplets to accumulate around the electrode and cause the droplets to recombine with each other or adhere to the electrode.

6. The solution containing the polymer substance ejected as described above becomes droplets (in some cases, they may already be solidified particles) with a uniform particle size that is synchronized with the cycle of the alternating current. The dispersion liquid is dispersed in the dispersion medium, and the dispersion liquid outlet 0 is dispersed as shown by the arrow.
3) and sent to additional processing cypress (not shown).

Next, the desired uniform polymer particles are produced by solidifying the droplets by, for example, volatilizing the solvent in the droplets by heating, gelling them by cooling, or adding a gelling promoter to this dispersion. Which of these methods is used to solidify the droplets can be determined mainly based on the solution properties.

For example, droplets using a mixed solvent of a volatile good solvent of a polymeric substance and a hardly volatile non-solvent as a solvent can be solidified by heating to volatilize the good solvent in the dispersion medium.

In addition, when using a solution containing a polymer substance that transitions from sol to gel at a certain temperature or lower, droplets are created from the solution in a sol state, and the droplets are solidified by lowering the temperature and turning the droplets into a gel. sell.

If the droplets cannot be solidified by such methods, a gelling promoter can be gradually added to solidify the droplets. The gelation promoter is a liquid that dissolves well in the solvent of the droplets, but is a non-solvent for the polymeric substance, for example, when the above-mentioned hydrophobic solvent is used as the solvent, the gelation promoter is used. As the alcohol, a monohydric or polyhydric alcohol having 1 to 4 carbon atoms can be used. Other examples include liquids containing cross-linking agents between polymeric substances, and liquids containing reagents that cause chemical changes such as hydrolysis to cause loss of solubility.

The microstructure of polymer particles can also be adjusted in various ways, including
Generally, if a droplet is solidified in a dilute solution or wave state, it becomes porous, and conversely, if it is made into a concentrated solution and then solidified, it becomes a dense structure. For example, if droplets made by dissolving a polymer substance in a volatile solvent are solidified by volatilizing the solvent, extremely dense polymer particles can be obtained. However, by adding a large amount of a non-volatile polymeric non-solvent to this solution, the droplets will gel with just a small amount of volatilization of the good solvent, resulting in polymer particles with an extremely porous structure. When other coagulation methods are adopted, the patterning of polymer particles can be adjusted basically using the same concept.

The droplets coagulated in the dispersion medium as described above are generally subjected to a crosslinking reaction, hydrolyzed, or introduced with ion exchange groups, antibodies, or other physiologically active substances to further increase their strength. It is then processed according to the intended use.

Next, a second method for producing uniform polymer particles of the present invention will be explained.

In the second manufacturing method, a vinyl polymerizable monomer solution is used instead of a solution of a polymeric substance. The vinyl polymerizable monomer liquid is dispersed in the form of uniform droplets in a dispersion medium that is incompatible or poorly compatible with the monomer liquid, as described below, and then polymerized by a known suspension polymerization method to form uniform polymer particles. It is said that

The dispersion may be of the 0/W type, so the monomers may be hydrophobic, or the dispersion may be of the W2O type, so the monomers may be hydrophilic. Further, the vinyl polymerizable monomers may be used alone or in combination of two or more. Furthermore, a monomer having two or more vinyl groups may be added. A non-reactive diluent may be added to the vinyl polymerizable monomer liquid composed of such monomers in order to adjust the structure of the resulting polymer particles. Specific examples of diluents include aliphatic saturated hydrocarbons having 5 to 12 carbon atoms, such as benzene, diethylbenzene, xylene, toluene, and 5 to 1 carbon atoms.
2 aliphatic lower alcohols, etc.

Specific examples of the hydrophobic monomer include styrene, ethylstyrene, chloromethylated styrene, methyl acrylate, methyl methacrylate, acrylonitrile,
Examples include monovinyl monomers such as maleic anhydride and vinyl acetate; polyvinyl monomers such as divinylbenzene, ethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, and diallyl phthalate.

Among these, styrene-divinylbenzene, chloromethylated styrene-divinylbenzene, styrene-maleic anhydride-divinylbenzene, methyl methacrylate-
Combinations such as divinylbenzene and methyl methacrylate-ethylene glycol dimethacrylate are particularly preferred. A polymerization initiator, such as benzoyl peroxide or azobisisobutyronitrile, which can generate free radicals by ultraviolet irradiation or heating is added to these hydrophobic monomer liquids.

Specific examples of the hydrophilic monomer include acrylamide, various alkyl acrylamides, hydroxyethyl methacrylate, acrylic acid, vinyl sulfonic acid, N-vinylpyrrolidone, and the like. Since these polymers are water-soluble, a crosslinking agent is usually used in combination to make them insolubilized by copolymerization with a crosslinking agent. Examples of crosslinking agents used include methylene bisacrylamide and polyethylene glycol dimethacrylate. Further, as a polymerization initiator, for example, hydrophilic ammonium sulfate or the like is added.

The viscosity of the vinyl monomer liquid is 50 cps or less at 30°C, preferably 20
cps or less. Further, there is no particular limit to the electrical conductivity of this liquid.

When a hydrophobic monomer is used as the dispersion medium,
As in the first production method, an aqueous solution of gelatin, methylcellulose, and polyvinyl alcohol to which any nonionic surfactant (approximately 0.2 to 5%) is added is usually used.

In addition, when using hydrophilic monomers, for example, hydrocarbon solvents such as toluene, xylene, tetralin, ligroin, liquid paraffin, halides such as carbon tetrachloride, trichloroethylene, 1,1,2.2-tetrachloroethylene, and chlorobenzene, Vegetable oils such as castor oil and cottonseed oil, silicone oils, etc. are used, and in the past, surfactants with a B value of 3 to 6, such as sorbitan monooleate and glycerol monostearate, are used.
~5% is added.

The physical properties (viscosity, electrical conductivity, inductivity, etc.) of such a dispersion medium may be the same as those of the dispersion medium used in the first production method.

In the second manufacturing method, droplets are formed in synchronization with the cycle of alternating current in the same manner as in the first manufacturing method using the vinyl monomer liquid and the dispersion medium using, for example, an apparatus as shown in FIG. By forming droplets using such a method, it is possible to stably produce small, uniform droplets without adhering the droplets to the nozzle or electrode.

The droplets thus generated are taken out from the dispersion liquid outlet 03) together with the dispersion medium and sent to additional processing.

The desired homogeneous polymer is then produced by polymerizing by heating or UV irradiation.

The particles obtained as described above may be further processed to introduce hydrophilic groups, ion exchange groups, and physiologically active substances such as antibodies, depending on the intended use.

By the first and second manufacturing methods as described above, the volume average particle diameter (see the above-mentioned Japanese Patent Application Laid-open No. 117039/1983) is 2.
Although they are small polymer particles with a diameter of 0 to 250 um, more than 95% of the total particle volume is within ±20 um of the average particle diameter.
The result is extremely uniform polymer particles within 10% of each other.

The method of the present invention will be explained in more detail below using Examples.

Example 1 5 parts (by weight, the same applies below) of cellulose triacetate was dissolved in a mixed solvent of 20 parts of n-butanol and 75 parts of methylene chloride. The viscosity of this solution was 5 cps at 30°C. A 1% aqueous solution of polyvinyl alcohol was used as a dispersion medium. The electrical conductivity of this aqueous solution is 0.6 μs/
It was cm.

These dispersions were produced in the following manner using the dispersion apparatus (1) shown in FIG.

4 Dispersion device (1) has an inner diameter of approximately 60 mm and a length of approximately 1000 m.
The nozzle (2) was made of stainless steel and had a diameter of 100 mm. The electrode (8) was made of stainless steel and had a ring shape with an inner diameter of 20 mm. A stainless steel pipe was connected between the nozzle and a metering pump (not shown). However, an insulating material was used for the connection to the pump. That is,
The piping components before the pump were electrically isolated from the nozzle.

The flow rates of the cellulose triacetate solution and the dispersion medium were set to 0.2 ml/min (corresponding to 11 when converted to Reynolds number) and 50 ml/min, respectively.

Further, the temperature was maintained at 30°C in both cases.

The electrode was fixed at a position 20 mm above the nozzle, and
II z, an AC voltage of 700 V was applied between the nozzle and the electrode.

In this state, droplets were formed that were synchronized with the cycle of the alternating current.

Note that the temperature inside the transfer tank 01) is adjusted to 30° C. by a jacket 02).

This dispersion wave was transferred from the outlet 03) to a tank equipped with a slowly rotating stirrer, and the methylene chloride was volatilized at 35°C for 5 hours to solidify the droplets.

The particles were dissolved in 0.6% caustic soda water at 20°C.
ne; After being dispersed, cellulose particles were obtained by washing with water. The particles have a true spherical shape with a volume average particle size of 901 parts m, and at least 99% of the particles are ±20% of the volume average particle size.
The uniformity was within the range of 1.

The production of these particles was carried out continuously for 8 hours, but the nozzle (
2) and the electrode (8) were not found to have adhered to each other.

Example 2 Instead of the cellulose triacetate solution, styrene, divinylbenzene, a diluent toluene/heptane (volume ratio 3/1) mixed solution, and a polymerization initiator benzoyl peroxide were used in amounts of 75 parts, 25 parts, 100 parts, and 100 parts, respectively. A solution consisting of 1 part was used. The viscosity of this solution is approximately 0.7c at 30℃
It was ps. Furthermore, the same 1% aqueous solution of polyvinyl alcohol as in Example 1 was used as the dispersion medium.

Using the monomer liquid and dispersion medium described above, droplets were formed in synchronization with the cycle of the AC voltage under the same conditions as in Example 1. The resulting dispersion was heated to 75° C. in a transfer tank aD, then transferred from the outlet 03) to a tank equipped with a stirrer, and maintained at this temperature for an additional 10 hours. After the polymerization was completed, the particles were collected and washed with acetone to remove the solvent.

The particles were also perfectly spherical, had a volume average particle diameter of 110 mm, and had extremely high uniformity with at least 99% of the particles falling within ±20% of the volume average particle diameter.

The production of these particles was carried out continuously for 8 hours, but the nozzle (
No particles were observed to adhere to 2) or the electrode (8).

[Effects of the Invention] In the manufacturing method of the present invention, minute droplets are directly formed in the dispersion medium, so there is no problem with the conventional method in which floating droplets are formed in a gas, such as the nozzle or electrode. Not only is it possible to avoid adhesion of droplets or coalescence due to collision of droplets, but also there is no noise caused by mechanical vibration, and minute polymer particles can be produced stably for a long period of time.

[Brief explanation of drawings]

FIG. 1 is a partial view of a uniform droplet production device (dispersion device) used in an example of the present invention, and FIG. 2 is an enlarged cross-sectional view of the nozzle tip. (Main numbers in the drawing) (2), Nozzle (7); AC power supply (8): Electrode

Claims (1)

[Claims] 1. A solution containing a particle-forming polymer substance having a viscosity of 50 cps or less is passed through a nozzle installed in a dispersion medium of this solution,
A number of droplets of the solution synchronized with the cycle of the AC voltage are ejected into the dispersion medium by ejecting them while applying a constant cycle of AC voltage between the nozzle and an electrode provided in the dispersion medium near the nozzle. Uniform polymer particles that are produced and then solidified by evaporating the solvent in the droplets by heating, gelling by cooling, or solidifying the droplets by adding a gelling promoter to the dispersion. manufacturing method. 2 A vinyl polymerizable monomer liquid with a viscosity of 50 cps or less is applied from a nozzle placed in the dispersion medium of this liquid, while applying a constant alternating current voltage between the nozzle and an electrode placed in the dispersion medium near the nozzle. A method for producing uniform polymer particles, characterized in that droplets of the liquid are generated in the dispersion medium in a number synchronized with the cycle of the alternating current voltage by jetting, and then polymerized.