JP4021980B2 - Cellulosic particles and method for producing the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cellulosic particle body and a method for producing the same.
[0002]
[Prior art]
Cellulose particles can be used as a carrier for immobilizing bacterial cells and enzymes, a carrier for adsorbing fragrances and chemicals, a carrier for purifying body fluids, cosmetic additives, etc. Widely used in many fields.
[0003]
Many studies have been conducted on cellulosic particles to date.
In JP-A-63-90501, a mixture of viscose and a water-soluble polymer compound is mixed with an anionic water-soluble compound to prepare a fine particle dispersion, which is solidified by heating or using a coagulant. After regenerating with acid, the water-soluble polymer is removed through the steps of coagulation, regeneration, and water washing, and the average particle size is 3 × 10. ^-Four m or less, pore size 2 × 10 ^-8 ~ 8x10 ^-7 There is a maximum value of the pore volume in the section of m, and the total pore volume of the holes in the section is 2.5 × 10 ^-Five m ^Three Disclosed is a method for obtaining a porous microcellulose particle body of at least / kg. The particles obtained by this method are those in which minute pores are present in the minute cellulose particles themselves.
[0004]
In JP-A-63-92602, viscose, calcium carbonate and a water-soluble anionic polymer compound are mixed to prepare a fine particle dispersion of viscose containing calcium carbonate. A method for obtaining a porous spherical cellulose-based particle body by acid decomposition of calcium carbonate after the addition is disclosed.
[0005]
However, in these techniques, the cellulosic particles obtained have a relatively small particle size. Therefore, when such cellulosic particles are used for applications such as fillers and adsorbents, the flow rate is high. It is difficult to process in a large amount, and there has been a risk that the cellulosic particles may be broken if the processing is forced to be performed with a high-speed flow. Moreover, when such a cellulosic particle body is used for body fluid treatment, there is a possibility that blood cells are clogged.
Therefore, it has sufficient mechanical strength, can be processed at a high flow rate, can utilize the pore structure inside the cellulosic particles, has a larger surface area, and does not clog even when used for body fluid treatment. Development of cellulosic particles is desired.
[0006]
[Problems to be solved by the invention]
In view of the above, an object of the present invention is to provide a cellulosic particle body capable of high flow rate treatment, excellent mechanical strength, and a large surface area, and a method for producing the same.
[0007]
[Means for Solving the Problems]
The present invention is a cellulose-based particle body composed of cellulose-based small particles, wherein the cellulose-based small particles are connected to each other, and there are voids between the cellulose-based small particles.
[0008]
Further, the present invention is a method for producing the above cellulose-based particle body, wherein the cellulose-based particle body is obtained by dispersing cellulose-based small particles in an alkaline solution to form a suspension, and contacting the suspension with a coagulation liquid. It is a manufacturing method.
The present invention is described in detail below.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The said cellulose small particle is comprised from cellulose materials, such as a cellulose, a cellulose derivative, a regenerated cellulose, for example.
The cellulose is not particularly limited, and examples thereof include those obtained by degreasing cotton fibers, hemp, pulp obtained from wood, and purified cellulose obtained by purifying pulp.
[0010]
The cellulose derivative is not particularly limited, and examples thereof include those obtained by esterifying a part of the hydroxyl group of cellulose (ester derivative); those obtained by etherifying the hydroxyl group of cellulose (ether derivative).
The ester derivative of cellulose is not particularly limited, and examples thereof include cellulose acetate, cellulose propionate, nitrocellulose, cellulose phosphate, cellulose acetate butyrate, cellulose nitrate, and cellulose dithiocarboxylate (viscose rayon). Can do.
The ether derivative of cellulose is not particularly limited, and examples thereof include methyl cellulose, ethyl cellulose, benzyl cellulose, trityl cellulose, cyanoethyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, aminoethyl cellulose, and oxyethyl cellulose.
[0011]
The regenerated cellulose is a cellulose derivative that is easy to mold once and then converted into cellulose again after being molded. Specifically, for example, cellulose ester derivatives such as cellulose acetate and cellulose propionate, etc. And the like prepared by hydrolysis.
[0012]
The cellulose-based small particles may be porous or may not be porous, but are preferably porous. When the cellulosic small particles are porous, the surface area relative to the volume of the cellulosic particles can be further increased.
[0013]
As the cellulose-based small particles, for example, gel filtration agents, raw materials for cellulosic ion exchangers, affinity chromatography carriers, polymer carriers, body fluid purification carriers, cosmetic additives, and the like are conventionally used. Things can be used.
[0014]
The cellulose-based small particles can be produced by a known method. For example, the porous cellulose-based small particles are disclosed in JP-A-63-90501, JP-A-63-92602, and the like. It can be produced by a conventional method. Specifically, for example, it can be produced by the following method.
[0015]
(1) An alkaline polymer aqueous solution containing cellulose xanthate and a water-soluble polymer compound and a water-soluble anionic polymer compound are mixed to prepare a fine particle dispersion of the alkaline polymer aqueous solution, and the dispersion is heated. Or mixed with a cellulose xanthate coagulant to coagulate the cellulose xanthate in the dispersion as fine particles. At this time, since the cellulose xanthate fine particles contain a water-soluble polymer compound, they are removed. Next, the cellulose xanthate fine particles are neutralized with an acid to regenerate the cellulose to obtain the desired cellulose-based small particles.
[0016]
In addition to the above, the cellulose xanthate fine particles can be solidified by adding an acid to the dispersion. In this case, after removing the water-soluble polymer compound, the added acid is neutralized to regenerate the cellulose and obtain the desired cellulose-based small particles.
[0017]
(2) Viscose, calcium carbonate and a water-soluble anionic polymer compound are mixed to produce a fine particle dispersion of calcium carbonate, and the dispersion is heated or a coagulant is mixed. Thus, the viscose in the dispersion is coagulated and then neutralized with an acid to produce cellulose fine particles. Thereafter, the cellulose fine particles are separated from the dispersion, and calcium carbonate is removed by acid decomposition, followed by drying to obtain the desired cellulose-based small particles.
[0018]
The average particle size of the cellulose-based small particles is 1 × 10 ^-6 ~ 500x10 ^-6 m is preferred. 1 × 10 ^-6 If it is less than m, sufficient voids cannot be provided between the cellulose-based small particles constituting the cellulose-based particle body, and 500 × 10 5 ^-6 If it exceeds m, since the self-weight of the cellulose-based small particles is large, it becomes impossible to hold the cellulose-based small particles constituting the cellulose-based particle body of the present invention in a connected state. Preferably 5 × 10 ^-6 ~ 100 × 10 ^-6 m.
[0019]
The cellulosic particles of the present invention are obtained by interconnecting the cellulosic small particles so as to provide voids between the particles of the cellulosic small particles.
The voids are voids formed inside the cellulosic particles of the present invention, whereby the cellulosic particles can have a large number of micropores on the surface and inside.
[0020]
The cellulosic particles of the present invention are preferably those obtained by connecting cellulosic small particles to each other in the presence of a binder. The present inventors have found that by interposing a binder between the cellulose-based small particles, the strength of the cellulose-based particle body of the present invention is remarkably increased as compared with the case where no binder is used. Further, it is an advantage of using the binder that the strength can be adjusted by adjusting the amount of the binder.
[0021]
The binder is not particularly limited, and examples thereof include organic compounds, inorganic compounds, organic synthetic low molecules, inorganic synthetic low molecules, organic natural low molecules, inorganic natural low molecules, organic synthetic polymers, inorganic synthetic polymers, and organic natural materials. Examples thereof include polymers and inorganic natural polymers.
[0022]
It does not specifically limit as said inorganic compound, For example, what produces | generates a three-dimensional network structure by contact with coagulating liquid can be used. As such a thing, water glass etc. are mentioned, for example. The water glass generally refers to a concentrated aqueous solution of sodium oxide or potassium oxide and silicon dioxide. This solution reacts with various metal salts, and precipitates grow in the solution. Cellulose small particles and water glass (used as a binder) are dispersed in an alkaline solution, and the above suspension is brought into contact with an aqueous solution of metal salt (used as a coagulating liquid) to cause precipitation. Cellulose-based particles obtained by connecting small particles to each other can be produced.
[0023]
The inorganic synthetic polymer is not particularly limited, and examples thereof include inorganic polymer flocculants such as polyaluminum chloride, polyaluminum sulfate, polyferric chloride, and ferric sulfate.
The organic synthetic polymer is not particularly limited, and examples thereof include organic polymer flocculants such as polyacrylonitrile, polyacrylamide, sodium polyacrylate, and acrylic acid-acrylamide copolymer.
The organic natural polymer is not particularly limited, and examples thereof include cellulosic materials, starch-based materials, and alginic acid-soluble salts.
[0024]
As the binder, a substance having a functional group capable of hydrogen bonding with a hydroxyl group in a cellulose molecule or a cellulose derivative molecule is preferable, and a substance having a chemical structure similar to cellulose is more preferable. Specific examples include cellulosic materials, starch-based materials, and alginic acid-soluble salts. These have a chemical structure similar to that of cellulose, and have a glucose structure similar to that of cellulose and a hydroxyl group associated therewith, so that hydrogen bonding is possible with the hydroxyl group of the cellulose molecule or cellulose derivative molecule. Hereinafter, these will be described in detail.
[0025]
The cellulose-based substance may be the same substance as or different from cellulose-based molecules such as cellulose, cellulose derivatives, and regenerated cellulose that constitute the cellulose-based small particles.
It does not specifically limit as said cellulose, What was mentioned above can be used.
It does not specifically limit as said cellulose derivative, What was mentioned above can be used.
It does not specifically limit as said regenerated cellulose, What was mentioned above can be used.
[0026]
The starch-based material is not particularly limited, and examples thereof include starch esters such as starch acetate, succinate, nitrate, phosphate, and xanthate; starch allyl ether, methyl ether, carboxymethyl ether, carboxy Examples include starch ethers such as ethyl ether, hydroxyethyl ether, and hydroxypropyl ether; degradation products of natural starch such as roasted dextrin and oxidized starch.
The roasted dextrin is not particularly limited, and examples thereof include white dextrin, yellow dextrin, and British gum.
The oxidized starch is not particularly limited, and examples thereof include hypochlorite oxidized starch and dialdehyde starch.
[0027]
The alginic acid-soluble salt is not particularly limited, and examples thereof include sodium alginate.
It is known that an aqueous solution of the above-mentioned alginic acid-soluble salt forms an insoluble salt by contact with an aqueous solution of a divalent or higher metal salt excluding magnesium ions and mercury ions. Since this insolubilization occurs instantaneously, an insoluble salt can be easily formed by dropping a droplet of an alginate-soluble salt aqueous solution into an aqueous solution of a divalent metal salt such as calcium chloride. For example, cellulose-based small particles and the above-mentioned alginic acid-soluble salt (used as a binder) are dispersed in an alkaline solution to form a suspension, and the suspension is an aqueous solution of a divalent or higher metal salt excluding magnesium ions and mercury ions. By contacting with (used as a coagulating liquid), an insoluble salt is formed, and a cellulose-based particle body formed by interconnecting cellulose-based small particles can be produced.
[0028]
These binders may be used alone or in combination of two or more kinds, including the cellulose-based materials and starch-based materials described above.
Moreover, the binder which is 2 or more types of covalent bonds of the molecule | numerator which comprises a binder can be used. Specifically, examples of the copolymer of the organic synthetic polymer and the organic natural polymer include an acrylamide-carboxymethyl cellulose graft polymer.
[0029]
In the cellulosic particle body, the mode in which the cellulosic small particles are connected to each other does not necessarily have to be based on a covalent bond, and the connection state between the particles can be substantially stably maintained. Any state that can be used. That is, the mode in which cellulose-based small particles are linked to each other includes, for example, linkage by entanglement of cellulose molecules or cellulose derivative molecules, linkage by chemical bonds such as hydrogen bonds, and the like.
[0030]
For example, the cellulose has a structure in which D-glucopyranose is linked by β1 → 4 glucoside bonds, and has three hydroxyl groups per glucose unit in the main chain. It is considered that hydrogen bonds are formed in the molecule, and further, hydrogen bonds are formed between the acetal oxygen. In the case of the cellulose derivative, it is considered that the unsubstituted hydroxyl group has the same action.
[0031]
When the cellulosic particles are formed by linking cellulosic small particles to each other in the presence of a binder, the cellulosic particles are linked by entanglement of molecules between the cellulosic small particles and the binder, cellulose The connection by a chemical bond such as a hydrogen bond between the system small particle and the binder is also included.
[0032]
When the state in which the small particles of the cellulosic particle body of the present invention are connected to each other is observed, the following three cases may occur.
(1) When the surfaces of adjacent small particles are connected so as to be in contact with each other at points.
(2) When the surfaces of adjacent small particles are in close contact with each other and are connected while maintaining contact with each other.
(3) When the surfaces of the adjacent small particles are separated from each other in appearance, and a structure having a fibrous shape or other shape is interposed between the small particles so as to bridge the surfaces.
[0033]
In the case where the cellulose-based particle body described above is formed by interconnecting cellulose-based small particles in the presence of a binder, the state of (3) above may be included. Alternatively, structures having other shapes are binders.
The space formed between the small particles in any one of the three connected states is a space between the cellulose small particles in the cellulose particle body of the present invention.
[0034]
The average particle size of the cellulosic particles of the present invention is 10 × 10. ^-6 ~ 5000 × 10 ^-6 m is preferable and is appropriately set according to the application.
The average particle size of the cellulose-based small particles is 1 × 10 ^-6 Since it is m or more, the cellulosic particle body formed by connecting the cellulosic small particles is 10 × 10 ^-6 Only when m is greater than or equal to m, a stable particle body is obtained. 10x10 ^-6 If it is less than m, the number of connection points is small, and the particles are easily broken, so that the particles cannot exist stably.
[0035]
The specific surface area of the cellulosic particles of the present invention upon drying is 2 × 10 ^Four m ² / Kg or more is preferable. 2 × 10 ^Four m ² If it is less than / kg, the working area for responding to the application becomes small. More preferably, 5 × 10 ^Four m ² / Kg or more.
[0036]
The shape of the cellulose-based particle body of the present invention is a cellulose-based particle body composed of cellulose-based small particles, and is formed by interconnecting cellulose-based small particles so as to provide a gap between the cellulose-based small particles. As long as it is not particularly limited, for example, the shape may be a spheroid, or may be substantially spherical.
[0037]
The cellulose-based particle body of the present invention can be produced by dispersing the cellulose-based small particles in an alkaline solution to form a suspension, and bringing the suspension into contact with a coagulation liquid.
[0038]
The alkaline solution used in the production method of the present invention is not particularly limited, and examples thereof include a sodium hydroxide aqueous solution, a lithium hydroxide aqueous solution, a potassium hydroxide aqueous solution, a cesium hydroxide aqueous solution, and a rubidium hydroxide aqueous solution. .
A thickener such as glycerin may be added to the alkaline solution for viscosity adjustment.
[0039]
The hydrogen ion concentration of the alkaline solution is not particularly limited as long as it is within the alkaline range, but the pH is preferably 9 or more. More preferably, the pH is 10 or more, and still more preferably 12 or more. When the pH is less than 10, when the suspension in which the cellulose-based small particles are dispersed is brought into contact with the coagulation liquid, the cellulose-based small particles may be dispersed and cannot be connected.
In this specification, the pH value is the molar concentration of hydrogen ion [H ⁺ ], When pH = −log _Ten [H ⁺ ] Is a value defined by
[0040]
The suspension concentration of the cellulose-based small particles is preferably 50 to 75% by volume.
The suspension concentration is the ratio of the total volume of cellulosic small particles present in the suspension to the suspension volume. The deposit formed by filtering the suspension has a suspension concentration of 100% by volume. When the cellulosic small particles are porous and the water content is high, the apparent specific gravity is not much different from the specific gravity of the solution, so that the volume% is substantially equal to the weight%.
When the suspension concentration of the cellulosic small particles is less than 50% by volume, when the droplets of the suspension are brought into contact with the coagulation liquid, a fragmented cellulosic particle body is obtained, and the strength thereof is also low. When the volume% is exceeded, droplets having a smooth surface cannot be obtained, and the shape of the cellulosic particles may be agglomerated. More preferably, it is 60-70 volume%.
[0041]
The suspension may be obtained by dispersing cellulose-based small particles and a binder in an alkaline solution.
The method for suspending the binder is not particularly limited. For example, after the binder is dissolved in the alkaline solution in advance, the solution or suspension is mixed with the cellulose-based small particles. It is done.
[0042]
The amount of the binder to be added cannot be generally determined depending on the molecular weight of the binder, but is usually 0 in a suspension prepared by dispersing the cellulose-based small particles and the binder in the alkaline solution. 0.01 to 50% by weight is preferred. If it is less than 0.01% by weight, there is no effect as a binder, and it does not contribute to an increase in the mechanical strength of the cellulosic particles compared to the cellulosic particles by using no binder, and 50% by weight. When it exceeds, it exists in excess between cellulosic small particles, and a space | gap disappears. More preferably, it is 0.1-30 weight%, More preferably, it is 0.2-20 weight%.
[0043]
The average particle size of the cellulose-based small particles is 1 × 10 as described above. ^-6 ~ 500x10 ^-6 m is preferred, but if it is within this range, the average particle size is 1 × 10 ^-6 When it is less than m, when the binder is added, it is possible to avoid the disadvantage that the binder enters the gap between the cellulose-based small particles constituting the cellulose-based particle body and fills the gap.
[0044]
The viscosity at room temperature of the suspension in which the cellulose-based small particles and the binder are dispersed in the alkaline solution is 5 × 10. ^-Four ~ 1x10 ^Four Pa · s is preferred. 5 × 10 ^-Four If it is less than Pa · s, the suspension droplets are not easily deformed into a spherical shape when they come into contact with the coagulation liquid, and 1 × 10 ^Four When Pa · s is exceeded, deformation is difficult when the suspension is made into droplets, and the suspension does not become spherical.
[0045]
As a method and apparatus for measuring the viscosity, 5 × 10 ^-Four ~ 1x10 ^Four It is not particularly limited as long as it is a known viscosity measuring method and viscosity measuring apparatus capable of measuring solution viscosity in the range of Pa · s. The viscosity here is a viscosity defined in JIS Z 8802-1959. When there is a shear rate (displacement rate) in the liquid, the velocity is perpendicular to the direction of the shear rate (displacement rate). The internal resistance of the fluid is indicated by the magnitude of the stress generated per unit area in the direction of, and its dimension is (mass) / (length × time). In the viscosity measurement in the above viscosity range, it is not always necessary to measure the entire viscosity range with one apparatus. In addition, a simple viscosity measuring method and viscosity measuring apparatus with a measurement accuracy of about 10% may be used, for example.
[0046]
The viscosity measuring device is not particularly limited, and examples thereof include a capillary viscometer, a short tube viscometer, a falling ball viscometer, a falling ball viscometer, a cylindrical drop viscometer, a coaxial cylindrical rotational viscometer, and a bubble viscometer. . Solution viscosity is 5 × 10 ^-Four ~ 1x10 ² In the range of Pa · s, a bubble viscometer is preferable, and 1-1 × 10 ^Four In the range of Pa · s, a coaxial cylindrical rotational viscometer is preferably used.
[0047]
By suspending the cellulose-based small particles in an alkaline solution, the cellulose or the cellulose derivative swells as alkali cellulose at the surface portion of the cellulose-based small particles, and further, hydrogen bonds are cut and cellulose molecules or The mobility of cellulose derivative molecules is significantly improved. When the binder is present together, the binder is easily taken up.
[0048]
The time for suspending the cellulose-based small particles in the alkaline solution is preferably 1 minute or longer. If it is less than 1 minute, it becomes difficult to swell cellulose or a cellulose derivative as alkali cellulose at the surface portion of the cellulose-based small particles, and it is difficult to sufficiently connect the cellulose-based small particles. More preferably, it is 1 hour or more.
[0049]
Next, the suspension is brought into contact with a coagulation liquid, and the cellulosic small particles are interconnected.
By bringing the suspension into contact with the coagulation liquid, the mobility of cellulose molecules or cellulose derivative molecules is remarkably reduced, and entanglement between cellulose molecules or cellulose derivative molecules of cellulose-based small particles, hydrogen bonding, or the like may occur. In the case where a binder is present together, the mobility of the binder is also significantly reduced, and molecular entanglement between the cellulose-based small particles and the binder, hydrogen bonding, and the like can occur.
[0050]
The coagulation liquid is not particularly limited as long as it loses the fluidity of the alkali cellulose or the alkali cellulose and the binder. For example, organic solvents such as ethanol and acetone; salt solutions such as calcium salts; hydrochloric acid Inorganic acid solutions such as sulfuric acid and phosphoric acid; organic acids such as acetic acid; solutions that are acidic solutions and have a pH value lower than the pH value of the suspension, pure water, and the like. These may be used alone or in combination of two or more.
[0051]
The method of bringing the suspension into contact with the coagulation liquid is not particularly limited, for example, a method of dispersing the suspension in the coagulation liquid; making the suspension into droplets and bringing it into contact with the coagulation liquid Method: A method in which the coagulation liquid is refined, for example, atomized and brought into contact with the suspension. Especially, the method of making the said suspension into a droplet and making the said droplet contact a coagulating liquid from the point which is easy to control the average particle diameter of the cellulose particle body obtained is preferable.
[0052]
When the suspension is a droplet and the droplet is brought into contact with the coagulating liquid, the suspension droplet has a diameter of 5 × 10 5. ^-3 m or less is preferable. Diameter 5x10 ^-3 If it exceeds m, the action exerted by the surface tension becomes small, and it becomes difficult to form droplets.
[0053]
The method of making the suspension into droplets is not particularly limited, and examples thereof include a method of discharging the suspension into a gas phase from a capillary and a method of using a sprayer. Among these, a nebulizer is preferably used from the viewpoint that micronized droplets can be obtained.
[0054]
The atomizer has a droplet diameter of 5 × 10 ^-3 The apparatus is not particularly limited as long as it can be subdivided into m or less, and examples thereof include a rotary disk type sprayer, a pressure nozzle type sprayer, and a two-fluid nozzle type sprayer.
[0055]
The above rotating disk type sprayer is to spray a solution on a high-speed disk, shake off the solution by centrifugal force, and collide with a gas such as air to be atomized. The average particle diameter of the atomized droplets can be easily controlled by appropriately adjusting the solution supply speed and the rotational speed of the high-speed disk.
[0056]
The pressure nozzle type sprayer discharges a high-pressure solution from a small hole and causes the solution to collide with a gas such as ambient air and spray the solution. The average particle size of the atomized droplets can be easily controlled by appropriately adjusting the solution supply rate, the applied pressure, and the diameter of the small holes.
[0057]
The above two-fluid nozzle type atomizer sprays the solution itself with a high-speed gas by a compressed gas even when the pressure is low. The average particle diameter of the atomized droplets can be easily controlled by appropriately adjusting the solution discharge speed and the compressed gas ejection speed.
[0058]
The diameter of the droplets of the suspension can be designed relatively freely by appropriately selecting the above-described method of forming droplets.
[0059]
The time for contacting the suspension with the coagulation liquid is preferably 1 second or longer. If it is less than 1 second, the cellulose-based small particles cannot be sufficiently connected. More preferably, it is 1 minute or more.
[0060]
Since the cellulosic particles of the present invention have voids between the particles of the cellulosic small particles, the surface area relative to the volume of the cellulosic particles is large, and the cells / enzyme immobilization carriers, fragrances, chemicals, etc. It can be suitably used as a carrier for adsorption, cosmetic additives and the like. Moreover, since the cellulosic particle body of the present invention has high strength, high flow rate treatment is possible. These uses can be appropriately selected depending on the size and internal structure of the cellulose-based particle body of the present invention.
[0061]
The cellulosic particles of the present invention may be used as they are, or modified and used by filling the voids between the cellulosic small particles with an inorganic substance, an organic substance, or reacting various substances. May be.
[0062]
In the method for producing a cellulose-based particle body of the present invention, the cellulose-based small particles can be easily connected to each other, and voids can be provided between the cellulose-based small particles. In addition, by appropriately selecting the droplets of the suspension, the average particle size of the obtained cellulose particles can be adjusted relatively freely according to the application.
[0063]
【Example】
Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.
[0064]
Example 1
Carboxymethyl cellulose (manufactured by Wako Pure Chemical Industries, Ltd.) and a 6N aqueous sodium hydroxide solution (pH = 14.8) were mixed to prepare a 5.6% by weight solution of carboxymethyl cellulose. Average particle size 25 × 10 ^-6 m porous cellulose particles (manufactured by Chisso Corporation) were mixed in the sodium hydroxide aqueous solution of carboxymethylcellulose (suspension concentration was 65% by volume, binder was 2.0% by weight) and stirred for 5 hours. Made contact. Then, hole diameter 0.5 × 10 ^-3 When the droplets of this suspension were brought into contact with a 99.5% ethanol solution with a micropipette of m, substantially spherical cellulosic particles were obtained. The particle size is about 0.6 × 10 ^-3 ~ 1x10 ^-3 m. Even when the obtained cellulose-based particles were washed with pure water and then shaken with the present cellulose-based particles in pure water, the shape did not collapse. In addition, the cellulosic particles are held between the thumb and the index finger, and the fingers are rubbed in the length direction of the fingers to obtain about 5 × 10 5. ^-3 The shape did not collapse even if it was rolled 5 times or more between m. In addition, the value of pH is the dissociation degree of aqueous sodium hydroxide solution and aqueous hydrochloric acid = 1, [H ⁺ ] X [OH ^- ] = 10 ^-14 As pH = -log _Ten [H ⁺ ] Was obtained from the formula. Thereafter, the pH value was determined in the same manner.
[0065]
The liquid in the obtained cellulose-based particles is replaced with pure water, then with ethanol, and with 2-methyl-2-propanol, and a freeze dryer (manufactured by Eiko Eng. Co., Ltd.) As shown in FIG. 1, the cellulosic particles were substantially spherical in shape, as observed in a scanning electron microscope (manufactured by Topcon Co., Ltd.). there were. As shown in FIGS. 2 and 3, there were voids between the small cellulose particles connected to each other. Moreover, as shown in FIG. 4, even after the connection, pores originally present in the porous cellulose-based small particles could be observed.
[0066]
Example 2
Average particle size 25 × 10 ^-6 m porous cellulose small particles (manufactured by Chisso) and 6N aqueous sodium hydroxide solution (pH = 14.8) (suspension concentration is 62% by volume, binder is 0.0% by weight) %) For 5 hours with stirring. Then, hole diameter 0.5 × 10 ^-3 When the droplets of the suspension were brought into contact with a 6N aqueous hydrochloric acid solution (pH = -0.8) with a micropipette of m, substantially spherical cellulosic particles were obtained. The particle size is about 1 × 10 ^-3 m.
[0067]
Cellulose particles by this production method that does not use a binder are obtained, but after washing with pure water after shaking, the shape of the cellulosic particles in pure water does not collapse, but is obtained. The cellulosic particles were held between the thumbs and the belly of the index finger, and the fingers were rubbed in parallel to the length direction of the fingers. ^-3 When rolled, the shape collapsed.
[0068]
Example 3
Carboxymethylcellulose and a 6N aqueous sodium hydroxide solution (pH = 14.8) were mixed to prepare a 5.6% by weight solution of carboxymethylcellulose. Average particle size 25 × 10 ^-6 m porous cellulose particles (manufactured by Chisso Corporation) were mixed in the sodium hydroxide aqueous solution of carboxymethylcellulose (suspension concentration 63% by volume, binder 2.0% by weight) and stirred for 5 hours. Made contact. Thereafter, compressed nitrogen gas was ejected from the outer nozzle of a two-fluid nozzle (having an inner nozzle and an outer nozzle concentrically), and at the same time, the suspension was ejected from the inner nozzle in the form of a mist. Nitrogen gas ejection speed is 3.3 × 10 ^-Four m ^Three / S, the discharge speed of the suspension is 1.1 × 10 ^-7 m ^Three / S. Inner nozzle diameter is 2.6 × 10 ^-3 m, outer nozzle diameter is 4.4 × 10 ^-3 m 2 fluid nozzles were used. The discharge height was 4 m. A 99.5% ethanol solution was used as a coagulation solution, and the solution and the liquid droplets of the suspension were brought into contact with each other to obtain the cellulose-based particles of the present invention in the solution. The average particle size is about 2 × 10 ^-Four m. Even when the obtained cellulose-based particles were washed with pure water and then shaken with the present cellulose-based particles in pure water, the shape did not collapse.
[0069]
The liquid in the obtained cellulose-based particles was replaced with pure water, then with ethanol, and with 2-methyl-2-propanol, and a freeze dryer (Eiko Eng. Co., Ltd.) The sample was freeze-dried and gold was deposited, and then observed with a scanning electron microscope (Topcon). The shape of the obtained cellulose particle body was substantially spherical, and there were voids between the cellulose small particles connected to each other. Even after connection, pores originally present in the porous cellulose-based small particles could be observed.
[0070]
Example 4
Sodium alginate (manufactured by Wako Pure Chemical Industries, Ltd.) and a 6N aqueous sodium hydroxide solution (pH = 14.8) were mixed to prepare a 3.6% by weight solution of sodium alginate. Average particle size 25 × 10 ^-6 m porous cellulose particles (manufactured by Chisso) were mixed in the sodium hydroxide aqueous solution of sodium alginate (suspension concentration: 65% by volume, binder: 1.3% by weight) and stirred for 6 hours. Made contact. Then, hole diameter 0.5 × 10 ^-3 When the droplets of this suspension were brought into contact with a 6N aqueous calcium chloride solution using an m micropipette, substantially spherical cellulosic particles were obtained. The particle size is about 0.7 × 10 ^-3 m. Even when the obtained cellulose-based particles were washed with pure water and then shaken with the present cellulose-based particles in pure water, the shape did not collapse. In addition, the cellulosic particle body is held between the thumb and the index finger, and the fingers are rubbed in parallel to the length direction of the fingers to obtain about 5 × 10 5. ^-3 The shape did not collapse even if it was rolled 5 times or more between m.
[0071]
The liquid in the obtained cellulose-based particles was replaced with pure water, then with ethanol, and with 2-methyl-2-propanol, and a freeze dryer (manufactured by Eiko Eng. Co., Ltd.) The sample was freeze-dried and gold was deposited, and then observed with a scanning electron microscope (Topcon). As shown in FIG. 5 in which a part of the obtained cellulose-based granular material was cut, the shape of the obtained granular material was substantially spherical. As shown in FIGS. 6 and 7, there were voids between the cellulose-based small particles connected to each other. Moreover, as shown in FIG. 8, even after connection, pores originally present in the porous cellulose-based small particles could be observed.
[0072]
Example 5
J sodium silicate 3 (concentrated aqueous solution of sodium oxide and silicon dioxide (water glass), manufactured by Nippon Kagaku Kogyo Co., Ltd.) and 6N aqueous sodium hydroxide solution (pH = 14.8) were mixed. A 30.6% by weight solution of No. 1 was prepared. Average particle size 25 × 10 ^-6 m porous cellulose small particles (manufactured by Chisso Corporation) were mixed in the sodium hydroxide aqueous solution of the above-mentioned J sodium silicate No. 3 (suspension concentration was 62 vol%, binder was 11.6 wt%) and stirring Then, contact was made for 6 hours. Then, hole diameter 0.5 × 10 ^-3 When the droplets of this suspension were brought into contact with a 6N aqueous calcium chloride solution using an m micropipette, substantially spherical cellulosic particles were obtained. The particle size is about 0.5 × 10 ^-3 m. Even when the obtained cellulose-based particles were washed with pure water and then shaken with the present cellulose-based particles in pure water, the shape did not collapse. In addition, the cellulosic particle body is held between the thumb and the index finger, and the fingers are rubbed in parallel to the length direction of the fingers to obtain about 5 × 10 5. ^-3 The shape did not collapse even if it was rolled 5 times or more between m.
[0073]
The liquid in the cellulosic particles is replaced with pure water, then with ethanol, and with 2-methyl-2-propanol, and a freeze dryer (manufactured by Eiko Eng. Co., Ltd.) is used. After lyophilization and vapor deposition of gold, observation with a scanning electron microscope (manufactured by Topcon Co., Ltd.) revealed that the resulting cellulose particle body was substantially spherical. In addition, there were voids between the mutually connected cellulose-based small particles, and pores originally present in the porous cellulose-based small particles were observed even after the connection.
[0074]
【The invention's effect】
Since the cellulosic particle body of the present invention has the above-described configuration, the size of the particles can be designed relatively freely according to the application. Depending on the size and internal structure, the carrier for gel filtration, cellulose It can be suitably used for applications such as a raw material of anionic ion exchanger, a carrier for affinity chromatography, a carrier for adsorption of fragrances and chemicals, a carrier for immobilizing bacterial cells and enzymes, a carrier for purifying body fluids, and the like. Moreover, since the manufacturing method of the cellulose particle body of this invention is as above-mentioned, the cellulose particle body of this invention can be manufactured easily.
[Brief description of the drawings]
FIG. 1 is a photograph in which the particle surface of a cellulosic particle of Example 1 is magnified 100 times.
FIG. 2 is a photograph in which the particle cross section of the cellulosic particle of Example 1 is magnified 100 times.
FIG. 3 is a photograph of a cross section of the cellulose-based particle body of Example 1 magnified 1000 times.
4 is a photograph in which the cross section of the cellulosic particle body of Example 1 is magnified 5000 times. FIG.
5 is a photograph in which the particle surface and cross section of the cellulosic particle body of Example 3 are enlarged 100 times. FIG.
6 is a photograph in which the particle surface and cross section of the cellulosic particle of Example 3 are magnified 200 times. FIG.
7 is a photograph in which the particle surface of the cellulosic particle body of Example 3 is magnified 1000 times. FIG.
8 is a photograph in which the particle cross section of the cellulosic particle body of Example 3 is magnified 5000 times. FIG.

Claims (6)

A cellulosic particle body composed of cellulosic small particles,
Cellulosic small particles are suspended in an alkaline solution having a pH of 10 or more to form a suspension having a suspension concentration of the cellulose small particles of 50 to 75% by volume, and the suspension is acidic, and Contacting with a coagulation liquid exhibiting a pH value lower than the pH value of the suspension;
The cellulosic small particles are connected to each other in the presence of a binder, and there are voids between the cellulosic small particles, and the particle size is 10 × 10 ^{−6 to} 5000 ×. Cellulosic particles having a size of 10 ⁻⁶ m. The cellulosic particle body according to claim 1, wherein the average particle diameter of the cellulosic small particles is 1 x ^{10-6 to} 500 x ^10-6 m.   The cellulosic particle body according to claim 1 or 2, wherein the cellulosic small particles are porous. It is a manufacturing method of the cellulose particle body of Claim 1, Comprising: A cellulose small particle was disperse | distributed in the alkaline solution whose pH is 10 or more, suspension concentration was 50-75 volume% , and the binder was made to coexist. a suspension, the suspension is acidic, and method for producing a cellulosic particle body comprising contacting the shown to coagulating liquid a pH value less than pH value of the suspension. The method for producing a cellulose-based particle body according to claim 4, wherein the suspension is made into droplets having a diameter of 5 × 10 ⁻³ m or less, and the droplets are brought into contact with a coagulation liquid. The viscosity of the suspension at room temperature is 5 × 10 ⁻⁴ to 1 × 10 ^4. It is Pa * s, The manufacturing method of the cellulose particle body of Claim 5.

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