JPH0354207A - Production of water-insoluble polymer having orderly shape - Google Patents

Abstract

PURPOSE:To produce a water-insol. polymer having a desired orderly shape by bringing a specific aq. soln. or dispersion contg. a water-sol. alginate salt into contact with an aq. soln. capable of gelling the salt to produce a water- insol. gel having a desired orderly shape and radical polymerizing the resulting gel. CONSTITUTION:A water-sol. alginate salt, a phosphate ester of the formula (wherein R1, R2, and R3 are each H or CH3), a crosslinkable vinyl monomer (e.g. N, N'-methylenebisacrylamide) having at least two radical-polymerizable vinyl groups, and a water-sol. radical polymerizable vinyl monomer (e.g. acrylamide) are dissolved ( some of these may be dispersed) in water. The resulting aq. soln. (dispersion) is brought into contact with an aq. soln. capable of gelling the alginate salt to produce a water-insol. gel having a desired orderly shape. The gel is then radical polymerized to produce a water-insol. polymer having a desired orderly shape.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a water-insoluble polymer, and more specifically, a method for producing a water-insoluble polymer in a desired shape with a uniform shape. Regarding the method.

[Conventional technology]

Conventionally, a water-insoluble polymer with a desired size and shape has been produced from a water-soluble radically polymerizable vinyl monomer and a crosslinkable monomer having two or more radically polymerizable vinyl groups. has problems with moldability, wide shape distribution, controllability of polymerization reaction, etc., and its industrial use has been extremely difficult.

Suspension polymerization has been used to produce particulate water-insoluble polymers using these monomers. In this suspension polymerization method, an aqueous monomer solution and a surfactant are added to a medium in which water and monomers do not dissolve at all or hardly dissolve, and are thoroughly stirred, so that the aqueous monomer solution becomes a suspension of fine particles. By adding a readily soluble polymerization initiator to the monomer, polymerization was carried out in suspension droplets of an aqueous monomer solution to produce particulate water-insoluble polymers. The particle size of the particulate water-insoluble polymer obtained by this conventional method varies depending on the medium used, the type of monomer and surfactant, the shape of the polymerization tank, the shape of the stirring blade and the stirring speed, etc. Usually, it is suitable for producing particulate water-insoluble polymers with a small particle size of 0.1 mm or less, and moreover, the particle size distribution range of the obtained particles is wide, and particulate polymers with a specific particle size can be produced. If it is necessary to use a polymer, the obtained particles must be sieved and used, and particulate polymers with a particle size other than the desired size are discarded. This is an economical manufacturing method. It cannot be said that k. Furthermore, it is extremely difficult to produce granular polymers with large particle diameters of several diameters or more, and if you try to produce large particle diameter polymers, large lumpy polymers will be produced and foul the walls of the polymerization tank. This tends to cause a situation in which it becomes difficult to continue the polymerization.
Furthermore, there is a drawback that water-insoluble polymers in shapes other than granules cannot be produced by this suspension polymerization method. The inventors have finally arrived at this invention as a result of intensive research into a method for stably producing a water-insoluble polymer with a desired shape and a narrow shape distribution. [Means for Solving the Problems] This invention provides (a) a water-soluble alginate, (b) a phosphoric acid ester represented by the following formula, 0 (in the formula, Rl, Ri and Rs are hydrogen or methyl, respectively). ), (c) a crosslinkable vinyl monomer having two or more radically polymerizable vinyl groups, and
(d) A water-soluble radically polymerizable vinyl monomer is dissolved or partially suspended in water, and the aqueous solution or suspension is used as a solution capable of gelling the water-soluble alginate. By contacting, a water-insoluble gel with a desired shape with a uniform shape is formed, and then this gel is radically polymerized to produce a water-insoluble polymer with a desired shape with a uniform shape. Consists of. In the method of this invention, when a water-insoluble polymer with a desired shape and a uniform shape is produced, a crosslinkable vinyl monomer, a water-soluble radically polymerizable monomer, and, if necessary, a radical initiator, In advance, the alginate is dissolved or partially suspended in water together with the water-soluble alginate, and this liquid is brought into contact with a liquid having the ability to gel the alginate to first gel it. , a water-soluble alginate used for the gelation of a solution of the radically polymerizable monomer, which is polymerized into a water-insoluble polymer after being formed into a gel of the desired shape. Examples include sodium alginate, potassium alginate, or ammonium alginate. Alginic acid is a copolymer of mannuronic acid and guluronic acid obtained from seaweed, and its composition varies depending on the place of production and the time of collection, but the composition of the one that gels with a water-soluble alginate gelling agent The method of this invention can be used regardless of the method. Also,
The molecular weight of alginic acid is 1,000 to l. 0
Values within the range 00, 000 are used. The alginate concentration of the water-soluble alginate aqueous solution for producing alginate gel is usually 0.1 to 20 wt. %, preferably 0.5-10wt. It is within the range of %. If the concentration of alginate is low, the strength of the resulting alginate gel will be low, making it difficult to form a gel with the desired shape, and the radically polymerizable heptanomer will easily flow out of the gel, and conversely, the alginate gel will be difficult to form into a desired shape. If the concentration is high,
Although the strength of the resulting alginate gel increases, the viscosity of the alginate solution increases, making it difficult to handle and molding into a gel of a desired shape, and in addition, it is not economical. It is preferable that dissolved oxygen be removed from the water-soluble alginate aqueous solution containing these radically polymerizable monomers for the purpose of smooth progress of the subsequent polymerization reaction. An inert gas such as nitrogen may be introduced for this purpose.

Examples of the solution capable of gelling the aqueous solution of water-soluble alginate used in the method of the present invention include an acidic aqueous solution with a pH of 7 or less, and an aqueous solution containing a polyvalent metal ion of divalent or higher valence other than magnesium and mercury. Examples of acidic aqueous solutions with p}17 or less include aqueous solutions of inorganic acids such as hydrochloric acid, sulfuric acid and nitric acid, and aqueous solutions of organic acids such as formic acid and acetic acid. Polyvalent metal ions include Ca, Fe, Co. Ni.
There are solutions containing metal ions such as Zn, Cd, Sr, Cu, and Pb. In addition, when including viable microorganisms as described below, the pH
Preferably, a 4-7 acid aqueous solution is used.

The method of producing an alginate gel containing a radically polymerizable monomer and, if necessary, a radical initiator in the method of this invention is an alginate aqueous solution or suspension containing a radically polymerizable monomer and, if necessary, a radical initiator. This can be done by contacting the alginate with a gelling agent solution. The shape of the resulting alginate gel can be greatly changed depending on the contact method.
For example, by dropping an alginate aqueous solution containing a radically polymerizable monomer into an alginate gelling agent solution, a spherical alginate gel with high sphericity and an extremely narrow particle size distribution range can be formed. The particle size of the spherical gel varies depending on the viscosity of the alginate aqueous solution, the shape of the alginate aqueous solution dropping nozzle, and other factors.

Furthermore, when an alginate aqueous solution containing a polymerizable monomer is injected into an alginate gelling agent solution, the shape of the alginate gel changes depending on the shape of the injection port.
Furthermore, after an alginate aqueous solution is injected into the mold in advance, the mold is partially opened and immersed in the gelling agent solution, so that the gelling agent solution flows into the inside of the mold from the opening. It penetrates into the mold, gels the surface upon contact with the alginate aqueous solution, penetrates into the interior, and finally gels the entire alginate aqueous solution inside the mold, thereby forming an alginate gel in the desired shape very easily. It is possible for children to do so.

Also, an alginate aqueous solution is injected and expanded into a shallow dish-shaped container, and an alginate gelling agent solution is gently poured from above to gel it into a thin plate shape, and then this gel is punched and formed. is also possible. It is also possible to form a gel in a desired shape by blending an alginate aqueous solution and an alginate gelling agent solution at high speed and then immediately injecting the mixture into a mold. During this gelation operation, an alkali phosphate or alkali argonate may be added as a gelation retardant. Furthermore, once the gel has been molded, it may be subjected to processing such as cutting or cutting in order to obtain a desired shape. The preparation of these alginate gels must be carried out at a temperature below the temperature at which the radical initiator begins to decompose and polymerize, and is usually preferably carried out within the range of 0 to 100°C. In addition, alginate gel is prepared under an atmosphere of an inert gas, such as nitrogen gas, in order to facilitate the subsequent polymerization reaction.
Preferably manipulated. The radically polymerizable monomer-containing alginic acid gel thus obtained is then subjected to a polymerization reaction.

The polymerization reaction is preferably carried out under conditions in which the alginate gel is placed in a solvent that does not interfere with radical polymerization, such as water, alcohol, or hydrogen carbide, and oxygen is removed. Of course, the polymerization reaction may be carried out without using a solvent and in the presence of an inert gas stream from which oxygen has been removed. The polymerization temperature varies depending on the type of radical initiator used, but it may be carried out at a temperature equal to or higher than the decomposition temperature of the radical initiator. If the polymerization reaction is preferably carried out at low temperatures, a substance that accelerates the decomposition of the radical initiator, or a liquid containing this substance, may be brought into contact with the gel in order to lower the decomposition temperature of the radical initiator. It will be done. For example, tetramethylethylenediamine is used for hydrogen peroxide, and ferrous ion is used for potassium persulfate. When the alginic acid gel containing a radically polymerizable monomer does not contain a radical initiator, the alginic acid gel can also be radically polymerized by radiation irradiation.

In the method of this invention, the steps of gelling the alginate aqueous solution or suspension and polymerizing the resulting gel may be performed separately or simultaneously. That is, when a gelling agent solution capable of gelling alginate is maintained at a temperature higher than the decomposition temperature of the radical initiator, and an aqueous alginate solution containing a radically polymerizable monomer is brought into contact with this solution, Polymerization is initiated simultaneously with the formation of alginate gel, and a water-insoluble polymer in the desired shape can be synthesized. The water-insoluble polymer thus obtained contains a portion of the alginate that was previously used and gelled. Depending on the intended use, the alginate in the water-insoluble polymer gel can be removed if it is unnecessary or has harmful effects. Substances that can remove alginate include those that can chelate polyvalent metal ions into water-soluble metal ions, such as sodium ethylenediaminetetraacetate, potassium salts, aqueous solutions of alkali metal phosphates, or alkali metal hydroxides. , carbonate aqueous solutions, etc., and if the water-insoluble polymer after radical polymerization is immersed in these aqueous solutions at a temperature in the range of 0 to 100°C, or washed with these aqueous solutions, good.

Although the water-insoluble polymer obtained by the method of this invention does not dissolve in water, it has sufficient hydrophilicity and the water-insoluble polymer obtained after polymerization is also swollen with water.
Depending on the purpose of use, the water-insoluble polymer may be used as it is after being swollen with water, or the water-insoluble polymer may be used after being sufficiently washed with water, and furthermore, it may be used after being dried. The water may be removed before use. In the method of this invention, representative examples of the phosphoric acid ester (b) include acid phosphooxyethyl acrylate (R1, RS and R3 in the above formula are all H), acid phosphooxyethyl methacrylate (11, and R2 are }I
．． R. is a methyl group), acid phosphooxybrobyl acrylate (R, or R2 is H, the other is a methyl group, R3 is H), acid phosphooxybrobyl methacrylate (Rl. 'Either one of R2 is H, the other is H) methyl group, R is a methyl group), etc., and these can be used alone or in a mixture of two or more. Typical examples of crosslinkable vinyl monomers having two or more radically polymerizable vinyl groups used in the method of this invention include N,N'-methylenebisacrylamide and N,N'-brobylenebisacrylamide. , N-acrylacrylamide, diacrylamide dimethyl ether, 1,2-diacrylamide ethylene glycol, ethylene urea bisacrylamide, polyethylene glycol, or acrylic acid or methacrylic acid of ethylene oxide and brobylene oxide copolymer having hydroxyl groups at both ends ester and l, 3. Examples include 5-triacrylhexahydro-8-triazine.

The ratio of phosphoric esters and crosslinkable vinyl monomers used in the production of the water-insoluble polymer in this invention is usually 100:0.05 to 100 by weight.
:20, preferably 100:0.1~IoO
: It is appropriate to use within the range of 15. Typical examples of the water-soluble radically polymerizable vinyl monomer used in the method of the present invention include unsaturated carboxylic acid salts such as alkali metal salts such as sodium and potassium of acrylic acid or methacrylic acid, hydroxyethyl acrylate, Hydroxybrobyl acrylate, aminoethyl acrylate, N-methylaminoethyl acrylate N,N-dimethylaminoethyl acrylate, hydroxyethyl methacrylate hydroxybrobyl methacrylate, aminoethyl methacrylate, N-methylaminoethyl methacrylate, N,N-dimethylamino Acrylic acid, esters of methacrylic acid such as ethyl methacrylate, acrylamide, methacrylamide, N-methylol acrylamide, N-methylolmethacrylamide, N-methylacrylamide, N. an alkali metal salt of N-dimethylacrylamide, NN-diethylacrylamide, 2-acrylamidoethanesulfonic acid or 2-acrylamidoethanesulfonic acid,
or acrylamide derivatives such as magnesium salts, methyl vinyl ketone, o-. m-. and alkali metal salts of p-aminostyrene, vinylsulfonic acid, or allylsulfonic acid, alkali metal salts or magnesium salts of styrenesulfonic acid, and N-vinylpyrrolidone, and these monomers may be used alone or in combination of two or more. is possible. The amount of the radically polymerizable vinyl monomer to the phosphoric acid ester is usually 1:0.01 to 1:10 in weight ratio, preferably I
: Within the range of 01 to 1:5. When a water-soluble radically polymerizable vinyl monomer is added to a phosphoric acid ester, the ratio of the crosslinkable vinyl monomer to the total weight of these monomers is usually 100:0.05-400:20, preferably +00: It is appropriate to use it in the range of 0.1-100:15.

When the proportion of the crosslinkable vinyl monomer is small, the resulting water-insoluble polymer is easily swollen by water, and when swollen by water, in the state of a so-called hydrous gel, it exhibits elasticity and has low tensile strength. On the other hand, if the ratio of crosslinkable vinyl monomer increases, the resulting water-insoluble polymer becomes difficult to swell with water, and the water-containing gel swollen with water tends to have a high tensile strength, but is brittle. become. Before polymerization, these radically polymerizable monomers are dissolved together with water-soluble alginic acid to form an alginic acid aqueous solution. may be done. The concentration of radically polymerizable monomers in the alginate aqueous solution is that of acid phospooxyethyl acnolates,
Expressed as the total amount of crosslinkable vinyl monomers, usually 0.1 to 50 wt. %, preferably 1
~20 wt. %, and in order to obtain a harder polymer, 20 to 45 wt. It is possible to set it as %. The concentration of all radically polymerizable monomers in the aqueous alginate solution is typically o. i~50 wt. %, preferably 1-20 wt. %, and 20 to 45 wt.% to obtain a harder polymer. It is possible to set it as %. In the method of this invention, a water-insoluble gel containing a radically polymerizable monomer by gelling alginate;
Hereinafter, this will be abbreviated as alginate gel and will be subjected to a polymerization reaction, and it is usually preferable to use a radical initiator in this polymerization reaction. Radical initiators used include hydrogen peroxide, sodium persulfate,
Common water-soluble radical initiators include potassium persulfate and ammonium persulfate. These can usually be added to the alginate aqueous solution before preparing the alginate gel. Of course, radical initiators that are sparingly or completely insoluble in water can also be used after being dispersed in the aqueous alginate solution. That is, these radical initiators can be contained in the alginate gel in the same way as the polymerizable monomers.

Of course, before the subsequent radical polymerization reaction, consideration must be given to things such as being kept at a low temperature or using a radical initiator that is difficult to decompose at low temperatures, so that the decomposition of the radical initiator can be suppressed. preferable. As mentioned above, if the polymerization reaction is carried out using radiation or the like, it is possible to avoid containing a radical initiator in the alginate gel. Radical initiator dosages are typically 0.0000000000000 for radically polymerizable vinyl monomers, including crosslinkable vinyl monomers. Ol
-10%, preferably 0.1-5%.
Furthermore, there is no problem in adding anything other than these radical initiators that does not interfere with the alginate gel production reaction and polymerization reaction. (Effect of the Invention 1) When the well-shaped water-insoluble polymer obtained by the method of the present invention is used as a carrier for an enzyme active substance, the advantage of its well-shaped shape is utilized.

In particular, if target microorganisms are added at a stage before the alginate gel is prepared, it is possible to encapsulate the microorganisms and form a well-shaped water-insoluble polymer. It can be used effectively for the enzymatic reaction used. In addition, since the dried water-insoluble polymer obtained by the method of this invention has extremely high water absorption,
Can be used as a water-absorbing polymer, and can be used as a soil conditioner,
Its characteristics as a well-shaped water-insoluble polymer can also be used as sanitary materials such as disposable diapers and sanitary napkins. The alginate contained in the water-insoluble polymer obtained by this invention can be removed by contacting it with a reagent capable of dissolving the alginate gel, if necessary, so that the alginate gel does not contain alginic acid and has a uniform shape. water-insoluble polymers can be produced. In addition, not only can a polymer with a desired shape be produced, but also the heat of polymerization accompanying polymerization can be easily removed, the polymerization reaction can be controlled, and the polymerization tank is hardly contaminated. There are also advantages. [Examples] Examples are given below to explain the method of the present invention in more detail, but the method of the present invention is not limited to these Examples. Example Acid phosphooxyethyl methacrylate log, Acrylamide 5g, Ig N. N'-methylenebis(
Acrylamide) Ig, 2 g of sodium alginate (Duck Algin NSPMJ manufactured by Kamogawa Kasei) were dissolved in water to make a total of 100 g, and an additional 5 wt.%
An aqueous solution was prepared with a concentration of ammonium persulfate aqueous solution lmI2 and bubbled with nitrogen gas. The above aqueous solution was added dropwise to a solution of tetramethylethylenediamine Ig and calcium chloride 6g dissolved in 300 mβ of water under a nitrogen stream while maintaining the liquid temperature at 20°C. The aqueous solution containing the generated spherical particulate gel was kept at 50°C under a nitrogen stream and the polymerization reaction was continued for 1 hour, resulting in a spherical water-insoluble copolymer with a uniform particle size of 2 mm. A union was created.

Claims (1)

[Claims] a) Water-soluble alginate, b) Phosphate ester represented by the following formula, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (In the formula, R_1, R_2 and R3 are hydrogen, or a methyl group), c) a crosslinkable vinyl monomer having two or more radically polymerizable vinyl groups, and d) a water-soluble radically polymerizable vinyl monomer dissolved in water, or a part thereof. This aqueous solution by suspending
Alternatively, the suspension is brought into contact with an aqueous solution that gels a water-soluble alginate to form a well-shaped water-insoluble gel.
A method for producing a water-insoluble polymer with a well-defined shape, characterized in that the gel is then subjected to radical polymerization to produce a water-insoluble polymer.