JPH0131936B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a particulate ion exchange resin and a method for producing the same. The present invention particularly relates to spherical crosslinked emulsion copolymer particles having weakly acidic cation exchange functionalities and having a size of 0.01 to 1.5 micrometers in diameter, as well as emulsions of these particles. The invention further relates to the manufacture of these particles and emulsions and the use of these particles and emulsions for removing dissolved or undissolved substances from liquids. [Prior Art and Problems to be Solved by the Invention] Finely ground ion exchange materials are widely used as filter media for simultaneous filtration and deionization of condensate water from steam turbine generators, and It is used less widely in pharmaceutical and other commercial applications such as drug carriers and tablet device integrators. In the past, such finely divided ion exchange materials have been produced by grinding ion exchange particles produced by conventional methods involving separate steps of polymerization, i.e., suspension polymerization in most cases, and functionalization; Manufactured by physically reducing particle size. Schultz and Kurtsk
Crook) [I&EC Product Research and Development Vol. 7, pp. 120-125,
June 1968 (I&EC Product Research and
Development, Vol.7, Pp・120−125, June,
(1968)] have produced particles of ground ion exchange resin with an average diameter of 1 micron or less, but the particles are not spherical and the diameter for a given sample of such material is The range is large and therefore the particle size is not uniform. Even though the large particles represent a small proportion of the total number of ground particles, the large particles will represent a much larger proportion of the weight of the sample. As a result, in such a crushed resin,
A significant proportion of the weight of the ion exchange resin material settles out of the aqueous suspension. Suspension polymerization involves suspending droplets of an organic liquid containing monomers, polymerization initiators, and suspension stabilizers in an aqueous phase medium. The droplet size is largely a function of the stirring speed and controls the final polymer particle size. The particle size is 5 micrometers (U.S. Patent No.
No. 3,357,158) or up to 10 micrometers (U.S. Pat. No. 3,991,017).
A range of up to about 40 micrometers is common. Ion exchange materials have also been produced by bulk polymerization. Physically reducing the particle size of such bulk or beaded polymers to sub-micron sizes is difficult, expensive, and
This results in the production of materials with undesirable physical properties such as irregular particle shapes and wide particle size distributions. Furthermore, this results in undesirable thermal deterioration of the resin. Sub-micron sized spherical polymer particles have been produced in the past, some with limited ion exchange functionality. These particles were obtained from monomers containing ion exchange functionality such as acrylic acid and methacrylic acid or dialkylaminoalkyl acrylate and methacrylate. In most cases, the polymerization reaction used was suspension polymerization. That is,
Haag et al. in their U.S. patent no.
No. 3847857, column 2, lines 56-59, states that in the production of functional crosslinked emulsion ion exchange resins for use in paints and other coatings, "...one or more species containing amine or quaternary ammonium groups... 5 to 70% by weight of the monomer of...
…"It was used. Rembaum et al.
al), whose U.S. Pat. No. 3,985,632, column 5, no.
In lines 25-46, a chromatographic adsorbent was similarly obtained by emulsion polymerization of a monomer mixture containing a small amount of monomer with amine functionality. Fitch, in his US Pat. No. 3,104,231, used up to 15% by weight of monomers containing carboxylic acid groups when making crosslinked emulsion copolymers. He states that when the amount of such monomers is higher than 15% by weight, "dissolution of the copolymer in water or dilute aqueous alkaline solutions or significant swelling of the copolymer in such aqueous media" will occur. Yes (column 6,
(line 70-column 7, line 4). Hatch, in US Pat. No. 3,957,698, describes precipitation polymerization to produce crosslinked spherical ion exchange resin particles with a size range similar to that of emulsion polymer particles. In the sedimentation method, large particles are originally obtained;
In the case of emulsion polymerization, it is 0.01 to 1.5 ₁₂ , whereas
ranges from 0.1 to 10 micrometers, and
It is necessary to precipitate the polymer particles from a monomer solvent solution in which the polymer is insoluble. In emulsion polymerization, the monomers are only slightly dissolved in the solvent and polymer particles are produced when the monomer-swollen soap micelles contact the solvent phase-initiating polymer chains. Hatch states that "Suitable microbead resins may be obtained by suspension or emulsion polymerization...". He further describes suspension polymerization, but does not give details of the emulsion polymerization method (column 3, lines 30-40).
Although Hatch's ion-exchange microbeads are weak acid resins made from carboxylic acid monomers such as acrylic or methacrylic acid by post-polymerization hydrolysis, he described the use of esters of the above acids. It's just that. Hatch gives an example of the production of microbeads from vinylbenzyl chloride (Example 4).
The particle size is 3-7 microns, clearly outside the scope of the present invention, and no attempt has been made to impart ion exchange functionality to the microbeads themselves prior to bonding them to the ion exchange resin matrix. Hayward, in its US Pat. No. 3,976,629, also used improved suspension polymerization and carboxylic acid monomers to produce weakly acidic cation exchange resins with a size of "less than 20 microns." Tamura discloses the production of strongly acidic cation exchange resin materials from emulsion copolymers (Journal of the Chemical Society of Japan, 76(4), pp. 654-658, 1976).
Tamura coagulated a styrene-divinylbenzene copolymer emulsion and then functionalized it with fuming sulfuric acid or chlorosulfuric acid. He then incorporated the coagulum into a polypropylene membrane, but did not teach anything about the coagulum becoming an emulsion again. [Means for Solving the Problems] The present invention provides a novel small particle size spherical weakly acidic cation exchange resin having a smaller particle size than those previously known. This resin is made from crosslinked emulsion copolymer particles and has a degree of functionalization of greater than 0.7 functional groups per monomer unit and up to 1.5. This resin is produced by functionalizing emulsion copolymer particles with weakly acidic cation exchange functionalities. Emulsion copolymer particles can be directly functionalized by hydrolysis and similar reactions. To facilitate handling of these particles, the emulsion can be coagulated and the large coagulum particles treated like large polymer beads for isolation and reaction. Alternatively, the emulsion copolymer particles can be dried prior to functionalization. After functionalization, the particles are processed as an emulsion of individual particles by high shear mixing, ultrasonic vibration, gentle grinding or other milling methods that break up the agglomerated pieces without destroying the spherical particles of the emulsion copolymer resin. Can be suspended. The weakly acidic cation exchange resin particles of the present invention have a diameter of 0.01 micrometer to 0.5 micrometer,
A narrow particle size range with an average value in the submicroscopic range (herein this range means having a particle size of 1.5 micrometers or less) which can vary up to 1.5 micrometers in diameter by using further specialized techniques. It can be obtained with Figures 1 to 3 and Figures 4a to 4d show ion exchange resins using the same emulsion copolymer as the resin particles of the present invention as a matrix as supporting evidence of the appearance and particle size distribution of the weakly acidic cation exchange resin particles of the present invention. This is an electron micrograph of particles. Figures 1 to 3 are
Figure 3 is a micrograph of three different sizes of hydroxyl type anion exchange emulsion resin particles at ×50,000 magnification. Figures 4a-4d are photomicrographs at four different magnifications of a single floc resulting from mixing cation exchange emulsion copolymer resin particles with anion exchange emulsion copolymer resin particles. Each of the materials shown in these micrographs was obtained by the methods taught herein. That is, FIG. 1 is derived from a copolymer containing 3% by weight of divinylbenzene and produced according to Reference Example 11 below and Reference Example 2 below.
strongly basic anion exchange in the hydroxyl ion form, coagulated according to Reference Example 14 below, chloromethylated and then aminated according to Reference Example 14 below, and further converted to the hydroxyl form according to Reference Example 17 below. 1 shows emulsion copolymer resin particles. Figure 2 shows a copolymer derived from a copolymer containing 3% by weight of divinylbenzene, prepared according to Reference Example 1 below, coagulated according to Reference Example 2 below, and made into Reference Example 14 below. This figure shows strongly basic anion-exchange emulsion resin particles in the hydroxyl ion form that were then chloromethylated, then aminated, and further converted to the hydroxyl form according to Reference Example 17 below. FIG. 3 shows strongly basic anion exchange emulsion copolymer resin particles in the hydroxyl ion form of Reference Example 17 below. Figure 4b shows the following reference example at a magnification of x300.
Fig. 4a shows the same floc at a magnification of x1000 and Fig. 4d shows the same floc at a magnification of x1000.
Figure 4c shows the same flock at 3000.
The same flock is shown at ×10000 magnification. It can be seen from the particles shown in the figures that they are generally spherical and have a relatively narrow size distribution when produced, and can be produced in different sizes. The particle sizes in these drawings range from about 0.017 micrometers to about 0.45 micrometers. Although strongly basic anion exchange emulsion copolymer resin particles are illustrated in the drawings, the particles of the weakly acidic cation exchange emulsion copolymer resin of the present invention also have a similar appearance and particle size distribution. The agglomeration of particles in these drawings was determined by the laboratory preparing the optical micrographs.
It was concluded that the micrographs were artifacts related to the preparation of the samples. It should be noted that in the case of strong acids and bases as well as weak base ion exchange resin particles, physically stable aggregates of crosslinked emulsion copolymer particles are formed, making it difficult to isolate the copolymer for functionalization. It is possible. Because of their small particle size, emulsion copolymer particles cannot be practically filtered or otherwise separated from their reaction solution, and functionalized copolymer particles cannot be separated from functionalized mixtures. I can't. After aggregation, the large aggregated particles can be filtered and washed in much the same way as conventional sized ion exchange resin beads. Functionalization of aggregated emulsion copolymers requires conventional reactions well known in the art. On the other hand, the weakly acidic cation exchange emulsion copolymer resin particles of the present invention have physical properties similar to those of the resins described above, but in some cases do not require aggregation prior to isolation and functionalization. That is, in a preferred method for producing weakly acidic cation exchange resin particles of the present invention, it is necessary to add a crosslinked acrylic ester emulsion copolymer to an alkali hydroxide solution. In doing so, the particles contained in the emulsion agglomerate, but the copolymer ester bonds are hydrolyzed to form carboxylic acid groups in the form of their salts, so that the formed coagulum is resuspended and functionalized. A salt emulsion of the resin particles is formed. The functional groups of the resin particles can then be converted to the free acid form by treating the emulsion with a conventional strongly acidic cation exchange resin in the free acid form. An emulsion copolymer that can be used to form a floc (described later) with the weakly acidic cation exchange resin of the present invention and the resin particles of the present invention The emulsion copolymer used to form the ion exchange resin particles can be produced by conventional emulsion polymerization techniques. Can be done. These prior art techniques require the polymerization of emulsions consisting primarily of, but not limited to, monomers and surfactants. Polymerization is usually initiated by a water-soluble initiator. It is well known that the action of most of these initiators is inhibited in the presence of oxygen, so oxygen exclusion techniques such as the use of inert gas atmospheres, deoxygenated solutions and emulsions are used during polymerization. It is preferable to do so. The choice of surfactant and initiator will be clear to those skilled in the art. The monomers used to form the emulsion copolymer consist of a large amount of a monoethylenically unsaturated monomer, or a mixture of these monomers, and a small amount of a polyethylenically unsaturated monomer, or a mixture of these monomers, which has the effect of crosslinking the polymer. Examples of monoethylenically unsaturated monomers useful in making emulsion copolymers include polycyclic aromatic monomers such as vinylnaphthalene and monoethylenically substituted monomers such as styrene and substituted styrenes containing ethylvinylbenzene, vinyltoluene, and vinylbenzoyl chloride. Aromatic monomers including cyclic aromatic monomers; methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, t-butyl acrylate, ethylhexyl acrylate, cyclohexyl acrylate, isobornyl acrylate, benzyl acrylate, phenyl acrylate, Alkylphenyl acrylate, ethoxymethyl acrylate,
Ethoxyethyl acrylate, ethoxypropyl acrylate, propoxymethyl acrylate,
Mention may be made of acrylic acid monomers, including esters of methacrylic acid and acrylic acid, such as propoxyethyl acrylate, propoxypropyl acrylate, ethoxyphenyl acrylate, ethoxybenzyl acrylate, and the corresponding methacrylic esters. In the case of acrylic acid esters, in a preferred embodiment lower fatty acid esters of acrylic acid are used in which the aliphatic group has from 1 to 5 carbon atoms, in which the copolymers formed from the monomers form carboxylic acid cation exchange emulsions. It is a particularly preferred embodiment when used as an intermediate in the production of either copolymer resins or anion exchange emulsion copolymer resins.
When both a carboxylic acid exchanger and an anion exchanger are produced, the ester groups are exchanged. Thus, in practice methyl or ethyl acrylate is chosen. Examples of suitable polyunsaturated crosslinking monomers include divinylbenzene, divinylpyridine, divinyltoluene, divinylnaphthalene, ethylene glycol dimethacrylate, divinylxylene, divinylethylbenzene, divinylsulfone, divinylketone, divinylsulfide, trivinylbenzene, Mention may be made, for example, of vinylnaphthalene, trimethylolpropane trimethacrylate, polyvinylanthracene and polyvinyl ethers of glycols, glycerol, pentaerythritol and resorcinol. Particularly preferred crosslinking monomers include polyvinyl aromatic hydrocarbons such as divinylbenzene and trivinylbenzene, glycol dimethacrylates such as ethylene glycol dimethacrylate, and polyvinyl ethers of polyhydric alcohols such as divinoxyethane and trivinoxypropane. can. For the aqueous emulsion polymerization of mixtures of ethylenically unsaturated monomers, see, inter alia, U.S. Pat.
No. 2753318 and No. 2918391. As described above, the weakly acidic cation exchange emulsion copolymer resin particles of the present invention and other emulsion copolymer ion exchange resin particles that can be used to form a floc with the resin particles have a median particle size of 0.01 to 1.5 microns. meters can be obtained and also the preferred median particle size is
0.01-0.5 micrometers can be obtained. The median particle size of the resin particles can be precisely adjusted within these ranges, and the particle size distribution around the median is narrow, much narrower than the distribution obtained for finely milled resins of small particle size. . Although the particle size may be increased by functionalization, control of the particle size of the resin particles is via the emulsion copolymer. Such adjustment of emulsion copolymer particle size is already well known. For example, by varying the amount of surfactant present in the polymerization reaction mixture, the particle size can be adjusted within the copolymer particle size range of 0.05-0.3 micrometers; increasing the amount of surfactant Smaller emulsion copolymer particle sizes tend to be obtained. The amount of crosslinker in the polymer also tends to affect the particle size of the copolymer, with more highly crosslinked copolymer particles tending to swell less than less crosslinked particles when hydrated. . For particle sizes below 0.1 micrometer, the particle size can be adjusted down to 0.01 micrometer using a special surfactant as described in Reference Example 11 below. By further reducing the amount of surfactant, or
Pre-formed emulsion copolymer “seed”
Copolymer particles larger than 0.3 micrometers can be produced by producing particles even larger than the ("seed") particles. Polymer particles can be made as large as 1 micrometer in diameter by this method and then treated by functionalization.
Ion exchange resin particles with a diameter as large as 1.5 micrometers can be obtained. A method for producing large copolymer particles is explained in Reference Example 10 below. The amount of crosslinking agent can be selected from between about 0.1% and about 25%, more preferably from about 1% to about 20%. The amount of crosslinking agent depends on the particular type of resin, physical properties, and amount of functionality desired for the emulsion copolymer ion exchange resin product. For example, a sulfonic acid functionalized resin is obtained from an emulsion copolymer having more crosslinker than the copolymer to produce the amine functionalized resin.
Similarly, if very low swelling is desired, there are process advantages in which smaller reaction vessels can be used and larger amounts of crosslinking agent are used. Crosslinker in the range of about 3% to about 12% is common for sulfonic acid functionalized resins with low swelling, and higher amounts of crosslinker can be used when particularly low swelling is desired. . Amounts of crosslinking agent greater than about 25% may be used for special purposes, so long as the monoethylenically unsaturated monomer and crosslinking agent can be functionalized to yield a reasonable number of functional groups per monomer unit. can. If a faster reaction rate is desired, a smaller amount of crosslinking agent is selected. However, anion exchange emulsion copolymer resins preferably contain about 0.1% and about 7%
or more, preferably about 0.5 to about 3%
Contains a crosslinking agent in the range of . The selection of specific crosslinker usage levels to obtain the desired balance of physical properties is well known to those skilled in the art of conventional ion exchange resins, and the same guiding principles apply to emulsion copolymer resins. Applicable. To enable further handling, the emulsion copolymer may be processed in one of several known ways.
Agglomerate using two. One preferred aggregation method is to add the emulsion to hot brine;
Saturated to 2% aqueous solutions of sodium chloride or other inorganic salts such as calcium chloride, aluminum sulfate, etc. are used. Aqueous sulfuric acid solutions concentrated to about 4% by weight are also suitable, and aqueous solutions of alkaline hydroxides, such as aqueous solutions of potassium or sodium hydroxide, are particularly suitable for coagulation and simultaneous hydrolysis and functionalization of acrylic ester copolymers. Are suitable. When an emulsion is added to a stirring flocculant solution, the coagulum can be dispersed as particles with a particle size that depends on the stirring speed.The useful particle size ranges over a wide range, but small particles or smaller are recommended for ease of handling. It should not become powdery or powdery. Coagulant solutions can be added to the emulsion, but they tend to aggregate into bulky clumps rather than coagulum particles. The emulsion can be dried and agglomerated; spray drying is the preferred method for producing strongly basic resin products from aromatic copolymers. When the particles obtained by this method are used in subsequent functionalization reactions requiring filtration and washing, they tend to be too small to be easily handled. Other useful methods for flocculating copolymer emulsions include vigorous stirring, alternating freezing and thawing, and addition of organic solvents to the emulsion. Once produced, the agglomerate particles have sufficient cohesiveness to withstand normal handling techniques used for washing, filtration, and functionalization of conventional suspension polymerized ion exchange resin beads. The agglomerates are preferably dehydrated by evaporation at ambient or higher temperatures or by washing with an aqueous anhydrous organic solvent and subjected to conventional functionalization reactions. Generally, the reactions used to functionalize emulsion copolymer resin particles are the same as those used to make ion exchange resins from conventional suspension polymerized copolymers. Since a high degree of functionalization is desirable as it results in a high number of ion exchange functional sites per unit weight of resin, the weakly acidic cation exchange emulsion copolymer resin particles of the present invention have a high number of ion exchange functional sites per unit weight of resin. Constructed to have a functional group. A more preferred range is from 0.8 to 1.2 functional groups per monomer unit. The term "functional groups per monomer unit" herein refers to the ion exchange functional groups per total monomer unit of both the "backbone" monoethylenically unsaturated monomers and the crosslinking polyethylenically unsaturated monomers. means the number of For example, when making a copolymer using an aromatic backbone monomer and an aromatic crosslinker monomer, the above terms,
That is, "functional groups per monomer unit" means the number of functional groups per aromatic ring in the polymer. Similarly, for a copolymer of a functionalized acrylic acid backbone and an unfunctionalized aromatic crosslinker, the degree of functionalization is the ion exchange functionality per total monomer unit of acrylic acid monomer and aromatic monomer. . The degree of functionalization can also be thought of as the number of functional groups per mole of total monomers making up the copolymer. Some typical methods of functionalizing copolymers are discussed below. Note that other emulsion copolymer ion exchange resin particles that can be used for floc formation with the weakly acidic cation exchange emulsion copolymer resin particles of the present invention may also have the same degree of functionalization as the resin particles of the present invention as described above. You get what you have. The strongly acidic emulsion copolymer ion exchange resin particles that can be used in the below-described floc formation using the weakly acidic cation exchange resin particles of the present invention include, for example,
Agglomerated particles of cross-linked styrene or substituted styrene emulsion copolymer are heated with concentrated sulfuric acid to form a sulfonic acid functionalized resin, the product is washed with water to remove excess acid, and the agglomerated emulsion particles are prepared by the method described above. Obtained by resuspending. The weakly acidic cation exchange emulsion copolymer resin particles of the present invention can be obtained, for example, by hydrolyzing a crosslinked acrylic ester emulsion copolymer with a solution of an alkali metal hydroxide to produce carboxylic acid-functionalized resin particles. . It should be noted that in this particular method, there is no need to flocculate the emulsion prior to functionalization; flocculation occurs when the emulsion is added to the hydroxide solution, but the ester bonds are hydrolyzed. So the agglomerates of copolymer resin particles are resuspended. The carboxylic acid-functionalized resin particles obtained by this method are in the alkali metal form and can be converted to the free acid (hydrogen) form by contacting with conventional strongly acidic cation exchange resins in the hydrogen form. . Similarly, acrylic ester copolymer resins are hydrolyzed with strong acids to form carboxylic acids in the hydrogen form.
Functionalized resins can be produced, but in this case the product is not an emulsion, but rather a coagulum. Anion exchange resin particles that can be used to form a floc using the weakly acidic cation exchange resin particles of the present invention can be formed, for example, as follows. Strongly basic emulsion copolymer ion exchange resin particles can be obtained, for example, by chloromethylating aggregated particles of a crosslinked styrene emulsion copolymer with chloromethyl methyl ether in the presence of a Lewis acid such as aluminum chloride, and then forming the resulting emulsion copolymer intermediate. 3 like trimethylamine
by treatment with a secondary amine to generate a quaternary amine chloride functionality. Alternatively, strongly basic quaternary amine resin particles can be formed by combining a crosslinked acrylate emulsion copolymer with a tertiary amine group such as dimethylaminopropylamine or di(3-dimethylaminopropyl)-amine and a primary or secondary amine group. and then quaternizing the resulting weakly basic resin with an alkyl halide such as methyl chloride. Weakly basic emulsion copolymer ion exchange resin particles are used, for example, for styrene copolymers, a primary or secondary amine is used instead of a tertiary amine, and for acrylic acid ester copolymers, the resin is an alkyl halide. It is obtained in the same way as described for the strongly basic resins, except that it is not quaternized. The functionalized agglomerate particles have ion-exchange properties and have sufficient cohesive properties that they can be used in conventional ion-exchange processes in much the same way as conventional resin beads, except for the weakly acidic cations of the present invention. The preferred form of utilizing the exchange resin particles and the ion exchange emulsion polymer resin particles used to form the flocs utilizing the resin particles is in resuspended form. Resuspension of the functionalized agglomerated particles can be achieved by the methods described above, i.e., high shear mixing, ultrasonic vibration, gentle grinding, or other micronization methods that break up the agglomerates without destroying the spherical resin particles. It can be carried out. Natural re-emulsification of the emulsion copolymer resin particles occurs under certain conditions while obtaining a strongly basic product from the aromatic copolymer, obviating the need for a milling step. It should be noted that unfunctionalized emulsion copolymer particles are hydrophobic, which promotes agglomeration. Once functionalized, ion exchange resin particles are relatively hydrophilic and tend not to aggregate from emulsion form, even under conditions where unfunctionalized copolymer emulsions exhibit aggregation. Optical micrographs and other physical evidence show that emulsions of functionalized ion exchange resin particles contain primarily individually isolated particles. When a sample of such an emulsion is dried, the particles remain as individual particles, but
Alternatively, they may form clusters of small, loosely bound particles. These clusters, in contrast to the tightly bound nature of the clots, can be broken up with very gentle force, usually sufficient by rubbing between the fingers. Loosely bound clusters also tend to disperse spontaneously when added to water, forming emulsions of individual resin particles. In general, the weakly acidic cation exchange emulsion copolymer resin particles of the present invention can be used in any application in which ground ion exchange resins prepared by bulk or suspension polymerization are used; Because of their special properties, they are usually superior to conventional crushed resins. Furthermore, because of these special properties, the resins of the present invention can be used in a wide range of applications for which conventional milled resins are unsuitable. The uses of the weakly acidic cation exchange resin particles of the present invention will be described below. Among the uses of the weakly acidic cation exchange resin particles of the present invention are applications as orally administered drugs or drug treatments. Examples of these uses include the use of weakly acidic resin particles in the form of calcium or magnesium as gastric antacids and the use of weakly acidic resin particles in the form of calcium for the treatment of gallstones. Additionally, such uses include use as drug carriers and sustained release agents for drugs and other substances, with additional benefits in this and other applications.
There is masking of unpleasant flavors or odors of the adsorbed substances. The resin particles are further used in the treatment of acute poisonings such as heavy metals, drugs, and microbial endotoxins, exotoxins, phlegm toxins, and the like. Other uses in the field of internal medicine include the removal of pyrogens from substances in contact with blood, the removal of microorganisms from the stomach and intestines, and as an injectable contrast medium in radiography. Applications of the weakly acidic cation exchange resin particles of the invention are also in the fields of surgery and pharmaceutical therapy. Some of these uses include PH regulators, treatment of contact dermatitis caused by poison ivy or other drugs, antiperspirants, deodorants, skin disinfectants, for irritation control alone or simultaneously as a drug carrier. Irritation suppressants and insects, which also help
It is used to treat bites or stings caused by arachnids, snakes, etc. Domestic and industrial applications of the weakly acidic cation exchange resin particles of the invention are in the fields of flocculation, filtration and deionization. The floc produced by combining the weakly acidic cation exchange resin particles of the present invention with a weakly basic resin can be used for deionizing water, raw sugar, etc. The weakly acidic cation exchange resin particles of the present invention further find use as additives to paper and nonwoven materials. For example, the resin particles can be incorporated into disposable diapers and sanitary napkins as deodorants and disinfectants. The resin particles serve as dye receivers for incorporation into paper, fabrics and paints, and for this application the resin particles may be blended into the polymer prior to fiber extrusion. The weakly acidic cation exchange resin particles of the present invention have further uses as a compounding aid for concentrated industrial products.
Controlled release substrates for biologically active substances such as pesticides, fertilizers, growth hormones, minerals, suspending aids for pesticide formulations and similar applications where emulsifying properties and ion exchange activity of the resin are required. , and is useful as a PH regulator. The weakly acidic cation exchange resin particles of the present invention have yet further applications in the fields of catalysis and scavenging. These resin particles are suitable for example as high surface area, heterogeneous acid or base catalysts in the conversion of cumene hydroperoxide to phenol and acetone, as acid acceptors in the synthesis of ampicillin and as products for shifting the reaction equilibrium towards completion. , useful as by-product or metabolite scavengers. These resin particles can also serve as enzyme activators and substrates for immobilizing enzymes, for example in fructose conversion. Dry resin particles can also be used as a drying agent for organic solvents. Other uses of the weakly acidic cation exchange resin particles of the present invention include use as a replacement for sequestering agents and phosphate builders in synthetic detergents, use of weakly acidic resin particles, especially in the potassium form, as a tablet disintegrant; It has applications as a hydrometallurgical extractant for the recovery of germanium, uranium, zinc, etc. Due to the small particle size, the resin particles can be used for ultrafiltration within the lumen of fine hollow fibers. These resin particles can be used as ion exchangers or adsorbents for removing metals or metalloporphyrins from petroleum residues. These resin particles can be used as high surface area extractants for the purification of organic acids such as lactic acid, citric acid, tartaric acid and similar acids produced by fermentation. These resin particles can be used to remove proteins and amino acids from wastewater from sugar refining facilities, slaughterhouses, etc., and since resins containing these proteins and amino acids are palatable and tasteless, they can be directly applied to cattle etc. It can be used as livestock feed. The method of decolorizing and clarifying sugar using weakly acidic cation exchange resin particles of the present invention provides significant advantages over conventional methods. Traditionally, raw sugar solutions are treated with renewable adsorbents such as bone char, activated carbon, or conventional ion exchange resins. These adsorbents require chemical regenerants or heating for regeneration, which is undesirable because the resulting sugar solution is diluted. In refining facilities, it is common for some decolorization operation to follow the clarification operation, often including sulfur dioxide bleaching, the addition of non-recoverable powdered carbon, or the use of flocculants. By using the weakly acidic cation exchange resin particles of the present invention, decolorization and transparency can be performed in one step. When added to an impure sugar solution, these resin particles form a cohesive and filterable floc with the charged particulate impurities normally present in the solution. The resin particles are incorporated into the floc, but
To preserve its ion exchange functionality, dissolved ionic and colored impurities can be removed from the solution. These resin particles can further remove particulate and coloring impurities by co-precipitation during floc formation or by retaining such impurities during filtration of floc-containing solutions. Another mechanism by which impurities are removed from solutions by flocs is adsorption onto the particles that make up the flocs, and because the particle size is so small, these particles impart a high surface area to the flocs. By one or more of these mechanisms, the weakly acidic cation exchange resin particles of the present invention remove impurities that cause coloration and loss of clarity from sugar solutions, as well as precursors of salts and colored impurities. The flocs containing adsorbed and entrained impurities can be removed from the sugar solution by filtration, flotation or other known methods. Sugars that are processed include canola sugar, corn sugar, sugar beet sugar and other sugars. Due to the superior reaction rate of these emulsion polymer resin particles due to their fine particle size, the weakly acidic cation exchange emulsion copolymer resin particles of the present invention are more ion exchangers than conventional ion exchange resins used hitherto. The floc itself also has the advantage of acting as a filter aid. If there is not enough charged particulate impurity in the impure sugar solution to incorporate all of the added emulsion copolymer ion exchange resin particles into the floc, another flocculant can be added to the solution. Examples of such flocculants include ionic surfactants that have a charge opposite to that of the emulsion copolymer resin particles, nonionic surfactants that have a charge opposite to that of the emulsion copolymer resin particles, and finely divided surfactants that have a charge opposite to that of the emulsion copolymer resin particles. Ion exchange materials can be mentioned. Such ion exchange materials may be ground conventional resins or the various emulsion copolymer ion exchange resins mentioned above. Furthermore, the resin particles of the present invention themselves may be used as an aggregating agent for removing aggregation of other ion exchange resin particles. The weakly acidic cation exchange resins of the present invention can also be used to treat sugars, particularly sucrose for conversion. Conversion, the hydrolysis of 12-carbon sucrose to the 6-carbon sugars glucose and fructose, occurs in the presence of specific enzymes or hydrogen ions. Note that strongly acidic emulsion cation exchange resins are used to supply these hydrogen ions without introducing undesirable soluble anions into the sugar. Following conversion, the cation exchange emulsion resin particles are removed from the invert sugar solution using conventional flocculants or by adding anion exchange emulsion copolymer resin particles, such as strongly basic emulsion copolymer resin particles. be able to. When such emulsion copolymer resin particles are used, the resin particles tend to further clarify and decolorize the sugar solution, and the resulting floc acts as a filter aid. The advantage of such a method over conventional sucrose solution processing in a cation exchange resin bead layer is that it processes a more concentrated and therefore more viscous solution when using emulsion copolymer resin particles than bead resins. This means that it is possible. As described above, when cation-exchange emulsion copolymer resin particles are combined with anion-exchange emulsion copolymer resin particles, the oppositely charged particles of the two resin particles interact to form a loose, electrostatically bound floc. form. Such flocs have excellent properties for ion exchange in terms of reaction rate, as liquids easily penetrate into them, and the individual particles themselves are very small. Although the flocs are easily broken up by shear forces, the electrostatic attraction of the oppositely charged particles remains, so that when the shear forces are removed, the flocs will re-form. This allows the flocs to be transported with conventional liquid pumps as if they were liquids. In use, the floc can be supported on a relatively coarse, low pressure differential filter screen if electrostatic attraction forces minimize particle sloughage. In addition to their deionization properties, these flocs can also be used to remove ions and particulate matter from steam generator condensate with excellent filtration properties, as shown in Reference Example 19 below. Ionic and filterability can be used simultaneously. When the flock is used in this manner, it is typically preapplied to a filter cloth, screen, filter leaf, or other mechanical filtration device. The floc may be preformed by mixing an emulsion of cation exchange and anion exchange emulsion copolymer resin particles prior to transfer to the filter itself, or
The floc may be formed in the liquor that is treated and filtered by adding cation exchange and anion exchange emulsion copolymer resin particles to the liquor. The latter has the added advantage of entraining particulate matter within the floc as it forms. The weakly acidic cation exchange emulsion copolymer resin particles of the present invention can be mixed with strongly basic or weakly basic emulsion copolymer resin particles to form a floc. In addition, strongly acidic cation exchange emulsion copolymer resin particles may be used in combination with this floc formation as necessary. That is, the floc is formed by mixing particles of one or more cation-exchange emulsion copolymer resins with particles of one or more anion-exchange resins, including weakly basic and strongly basic emulsion copolymer resins, and the like. The weakly acidic and strongly acidic emulsion copolymer resins may be mixed together and these mixtures may be used to form the floc. Emulsion copolymer resin particles having different particle sizes may be mixed to form a floc, including a number of cation exchange emulsion copolymer resin particles having different particle sizes or a number of anion exchange emulsion copolymer resin particles having different particle sizes. Such mixtures can be used to control the texture of the floc and thus the filtration and other handling properties. The formation of flocs will be explained in Reference Example 18 and Example 5 below. The flocs obtained from the weakly acidic cation exchange resin particles and weakly basic emulsion copolymer resin particles of the present invention have another useful property of being able to be thermally regenerated. That is, the floc can be used to remove anions and cations from a relatively cold liquid, which are exchanged with hydrogen and hydroxyl ions from a relatively hot aqueous liquid during regeneration. These flocs differ from conventional thermally regenerable resins, which are usually large, hard beads with regions of both acidic and basic functionality. This thermally regenerable floc can form large, cohesive masses and can be used with moving bed deionization equipment. In this apparatus, the flocs are coated onto a moving filter support that transports the flocs continuously through a deionization section in contact with a cold processing solution and a regeneration section in contact with a hot aqueous regeneration solution. The flocs can similarly be used in a continuous deionization process where the flocs are pumped through a deionization vessel and a regeneration vessel, with the flocs moving through the deionization vessel in a direction opposite to the flow of process liquid. The reproducibility of a weak acid-weak base floc at two different PH values and a comparison of the heat capacity of this floc to that of a conventional thermally recyclable bead resin is illustrated in Example 6 below. When cation exchange and anion exchange emulsion copolymer resin particles are mixed to form a floc, a single particle develops an electrostatic attraction with two or more particles of opposite charge. In particular, e.g.
If particles of a larger charge, such as between 0.7 and 1.5 micrometers, are mixed with fine particles of the opposite charge, e.g. having a particle size of less than 0.1 micrometers, a large number of the fine particles will be Cluster around. the result,
The ratio of cation exchange emulsion copolymer resin particles to anion exchange emulsion copolymer resin particles in the floc can be varied over a wide range by adjusting the particle size.
The flocs are obtained by varying the ratio of cation exchange resin particles to anion exchange resin particles from about 9:1 to about 1:9. Even for particles of opposite charge having approximately the same particle size, the ratio of cation exchange resin particles to anion exchange resin particles is at least about 3:
2 to about 2:3, which is the preferred range regardless of particle size. A more preferred ratio of cation exchange resin particles to anion exchange resin particles is about 1:1. The weakly acidic cation exchange emulsion copolymer resin particles of the present invention are similar to conventional ion exchange resin particles,
That is, by contacting ion exchange resin particles having a particle size of about 40 micrometers or greater, and preferably with these ion exchange resins suitable for conventional ion exchange beds, one ionic form is removed from the other. can be converted into ionic form. Ion exchange resin particles having a diameter of approximately 40 micrometers or greater, whether spherical beads or other geometric shapes, are herein referred to as "microbeads". do. For reference, emulsion copolymer anion exchange resin particles obtained in chloride form can be prepared by passing an emulsion of the resin particles through a conventional layer of strongly basic anion exchange resin in hydroxyl form.
This can be converted to the hydroxyl form. The chloride ions of the emulsion resin are exchanged with the hydroxyl ions of the conventional large bead resin as the emulsion resin passes through the column. As ions are exchanged between each resin, the ionic form of conventional ion exchange resins also changes. This process can therefore be used to change the ionic form of emulsion copolymer resin particles to a desired form, or, as in ion exchange bed regeneration, to change a fixed bed resin to a desired ionic form. can. Individual or mixed emulsion copolymer resin particles as well as individual,
Or blended conventional resins can be used in this process. Emulsion copolymer resin particles are of the same ion exchange type as conventional resins.
As used herein, "ion exchange type" refers to the ionic type of the ion exchange functional group, ie, either substantially cationic (acidic) or substantially anionic (basic). Ion exchange can be carried out in batch processes where the exchange reaches equilibrium and in column or bed processes where continuous equilibration results in high conversions to the desired ionic form, as in conventional processes with ion exchange layers of ionized solutions. This occurs between resins. This process is described in Example 1 and Example 4.
and Reference Example 17. The following examples and reference examples are for illustrating the invention and are not intended to limit it. All percentages used herein are by weight unless otherwise specified and all reagents are of high quality commercially available materials. Reference Example 1 The production of styrene-divinylbenzene emulsion copolymer will be explained. 370g of deoxygenated water, Triton x-200 (Triton x
-200) (Philadelphia, Pennsylvania)
Rohm & Haas trademark for the sodium salt of alkylaryl polyether sulfonate surfactants containing 28% solids), Styrene 248.8
A monomer emulsion was obtained by vigorously stirring 51.2 g of commercially available divinylbenzene (54.7% divinylbenzene, the remainder being essentially ethylvinylbenzene) under a nitrogen atmosphere. Deoxygenated water 100
An aqueous initiator solution was obtained by dissolving 2.0 g of potassium persulfate in 50 g of the monomer solution, and 50 g of the monomer solution was added to this initiator solution. The mixture was stirred with a 1 inch vortex and heated to 70°C under nitrogen atmosphere. At the onset of polymerization, marked by a sudden decrease in opacity, addition of the remaining monomer emulsion was begun over a period of 1.5 hours. After this addition is complete, reduce the temperature to 70°C.
It was held for 1 hour. The polymer emulsion was cooled to room temperature and filtered through cheesecloth. The measured solids content of this emulsion was 45% of the calculated value.
%, it was 43.0%. Reference Example 2 Brine aggregation of the polymer emulsion obtained in Reference Example 1 will be explained. 1400 ml of 25% aqueous sodium chloride solution was heated to 100°C. While stirring the solution, 700 ml of the emulsion obtained in Reference Example 1 was added as fast as possible without letting the temperature of the solution drop below 95°C. Keep the temperature of the solution at 100-103℃
Hold for 30 minutes to form a solid coagulum US Standard Series _15-12
(Alternative designation number 100) Filtered through a sieve. The coagulum was washed with water and dried as a single liquid at 110°C. Yield after drying is 292.1
It was hot at g. Reference Example 3 Sulfuric acid aggregation of the polymer emulsion obtained in Reference Example 1 will be explained. 41 ml of the polymer emulsion of Reference Example 1 was added to 250 ml of concentrated sulfuric acid while stirring using a pasteur pipette, the tip of which was inserted below the surface of the sulfuric acid. A worm-like coagulum with a diameter of about 15 mm and a length of 5 to 7 mm was obtained. Reference Example 4 The preparation of a strongly acidic cation exchange material by sulfonating the coagulum of Reference Example 2 will be explained. Mix 20 g of the dry coagulum of Reference Example 2 with 120 ml of concentrated sulfuric acid,
The mixture was heated to 120° C. with stirring under a nitrogen atmosphere and maintained at this temperature for 5 hours. Cool the reaction mixture to approx.
Water was added as quickly as possible without allowing the temperature to rise above 95°C. The solid material was allowed to settle and the supernatant was removed. Add about 120 ml of water to this solid substance,
It was then removed. The solid material was transferred to a filter tube, rinsed with water and drained. The yield of this material was 103.8 g with a solids content of 31.7%. The cation exchange capacity of this material was 5.22 meq/g of material in dry H ⁺ form compared to the theoretical value of 5.26 meq/g. Here, the theoretical ion exchange capacity and the theoretical degree of functionalization are calculated on the assumption that there is one functional group per aromatic ring (styrene resin) or monomer unit (acrylic resin). This theoretical value is
Under certain conditions, the opposite may occur, and the measured value may be larger than the theoretical value. Reference Example 5 The chloromethylation and aminolysis of the coagulum in Reference Example 2 will be explained. Dry coagulum 20 of reference example 2
A sample of g was swollen in a mixture of 17 ml of chloromethyl methyl ether and 69 ml of propylene dichloride. While stirring the slurry, a solution of 19 g of aluminum chloride in 25 ml of chloromethyl methyl ether was slowly added, keeping the temperature below 32 DEG C. by cooling during the addition. The reaction mixture was held at 32°C for 2 hours and then cooled to 15°C. cool down
Water was added dropwise keeping the temperature below 30°C. The aqueous layer was decanted from the expanded organic phase, and the product was washed twice with water and once with a 4% aqueous solution of caustic soda.
Then, it was washed once more with water. The solid product was filtered. The weight of this filtered product wet with propylene chloride was 105 g. A 15 g sample of this chloromethylated intermediate was slurried with water containing 40 mg of poly(ethyleneimine) having a molecular weight of 1200. The mixture was heated and stripped of propylene chloride. Cool the mixture and add 25% trimethylamine 9
Added ml. The temperature of the mixture was raised to 70°C and held at that temperature for 5 hours, then raised to 95°C to strip excess trimethylamine. The resulting solid was transferred to a filter tube, washed with water, and drained. The yield of a substance with solids content of 35.9% is 14.6
It was hot at g. The anion exchange capacity of this material was 3.64 meq/g of dry material in chloride form. As a result of trace analysis, the composition was as follows. C 67.16% H 8.49% O 6.82% N 4.82% Cl 12.37% (O=H ₂ O correction value) N=3.7meq/g Cl=3.8meq/g Reference example 6 Vinylbenzyl chloride-divinylbenzene emulsion copolymer Describe the aminolysis of clots. An emulsion copolymer of vinylbenzyl chloride and divinylbenzene (commercially available, divinylbenzene content 54.7%, remainder essentially ethylvinylbenzene) was obtained by the method of Reference Example 12 below. This polymer contained 8% divinylbenzene. The actual solid content was 29.6%. The emulsion copolymer is allowed to coagulate and coagulate.
50 g was made into a slurry with a solution of 0.15 g of poly(ethyleneimine) having a molecular weight of 1200 in 100 ml of water. The slurry was heated to 60°C, held at that temperature for 1 hour, and transferred to a pressure reactor. 40 g of 40% dimethylamine and 5.4 g of 59% aqueous sodium hydroxide solution were added to the reactor. The mixture was stirred and heated to 60°C and held at that temperature for 1 hour, then heated to 87°C and held at that temperature for 4 hours. The reactor was cooled and purged with nitrogen, and the reaction mixture was filtered. The solids were washed with water and drained. The results of microanalysis on a dry sample with a small amount of solid content were as follows. C 81.59% H 9.00% O 2.52% N 6.57% (Results corrected with O = H ₂ O) N = 4.8meq/g (Theoretical value 5.3meq/g) Reference example 7 Production of methyl acrylate-divinylbenzene emulsion copolymer I will explain about it. Triton x-200 in 360g of deoxygenated water
A 24 g dispersion was prepared in a round bottom flask under a nitrogen atmosphere and stirred with a 1-inch vortex. A mixture of 29 g of divinylbenzene (commercially available, 55.2% divinylbenzene content with the remainder essentially ethylvinylbenzene) and 171 g of methyl methacrylate was added to this aqueous dispersion, followed by 4 ml of a freshly prepared 820 ppm ferrous sulfate solution and filtrate. 50 ml of deoxygenated water containing 1.0 g of ammonium sulfate solution was added. Stir this mixture for about 15 minutes, cool and
The temperature was 20℃. A solution of 1.0 g of sodium metabisulfite in 20 ml of water and 5 drops of 70% t-butyl hydroperoxide were added to this mixture. After a 5 minute induction period, the temperature rose to 80°C for 6 minutes and then gradually decreased. After 30 minutes, the mixture was cooled to room temperature and filtered through cheesecloth. The solid content of the filtered emulsion was 31.4% of the theoretical value.
It was 31.0%. Example 1 The preparation of a weak acid functionalized ion exchange resin emulsion by hydrolysis and resuspension of the methyl acrylate-divinylbenzene copolymer of Reference Example 7 is described. 200g of the emulsion sample obtained in Reference Example 7 was added to a 50% caustic soda solution in 250ml of water.
Upon addition to 57.4 g of the stirring solution (20% excess as base), flocculation occurred. The mixture was heated to 93°C, held at that temperature for 2 hours, and cooled to room temperature. While this coagulum is being stirred and heated,
Seen resuspending in caustic soda solution. The emulsion product was diluted with water to 800-850 ml and Amberlite IR-120 cation exchange resin in H ⁺ form (sulfonic acid functionalized, styrene/divinylbenzene gel cation exchange bead resin) • Excess caustic soda was removed through a Haas Co. trademark) column to convert the product to the free acid form. The solid content of the resulting emulsion was 4.74%
The weak acid cation exchange capacity is about the dry polymer.
It was 9.4meq/g. Example 2 The resuspension of the functionalized emulsion copolymer aggregate obtained in Example 1 is described. The functionalized coagulum was transferred to a high speed blender vessel (Waring Blender Model 7011-31BL41 bottle assembly) and covered with water. The blender was run on high or low speed for 30 seconds to 20 minutes as required to resuspend the emulsion. Reference Example 8 Aminolysis and resuspension of the emulsion copolymer coagulum obtained by the method described in Reference Example 6 will be explained. A 17 g sample of the coagulum was slurried in 125 ml of water and 9.0 g of anhydrous trimethylamine was added. Temperatures were seen rising to 33°C. The slurry was further heated to 65° C. and excess trimethylamine was removed with a stream of nitrogen gas. The resulting product was very concentrated but completely suspended. The solids content of the emulsion was 16.3%. Reference Example 9 A sample of the OH ^- form of a strong base emulsion copolymer ion exchange resin obtained by aminating a chloromethylated styrene-7% divinylbenzene emulsion copolymer with trimethylamine as described in Reference Examples 1, 2 and 5. The particle size distribution was measured using electron optical micrographs. Average particle size is 147 nanometers (1 micrometer = 1000 nanometers)
About 76% of the particle sizes were in the 18-nanometer range and about 95% of the particle sizes were in the 33-nanometer range. Example 3 The particle size distribution of a weakly acidic carboxylic acid functionalized acrylate emulsion copolymer ion exchange resin sample containing 8% divinylbenzene in H ⁺ form obtained as described in Reference Example 7 and Example 1 was electronically determined. Measured using an optical microscope. The average particle size was 48 nanometers, with about 84% of the particle sizes in the 19-nanometer range and about 95% of the particle sizes in the 29-nanometer range. Reference example 10 Monomer solution was pre-formed
The preparation of styrene-divinylbenzene emulsion copolymers with particle sizes greater than _0.512 by a method of polymerization in addition to copolymer emulsions is described. Monomer emulsion: 180g of deoxygenated water, Triton x-200
14.3 g, styrene 377.8 g, divinylbenzene (54% divinylbenzene, remainder mainly ethylvinylbenzene) 22.2 g and ammonium persulfate 0.8 g under nitrogen atmosphere with vigorous stirring. Deoxygenated water in a separate container under nitrogen atmosphere
348 g was stirred with a 1-inch vortex and heated to 95°C. To this was added 13 g of a previously prepared emulsion copolymer, followed by 1.2 g of ammonium persulfate. (The pre-prepared emulsion copolymer was pre-prepared according to the method of Reference Example 1, had a particle size of about _0.1-12 , and had a solid content of 43.3%.
3% divinylbenzene-styrene emulsion copolymer. ) The mixture was stirred for 30 seconds and the monomer emulsion thus obtained was added dropwise over a period of 3.5 hours, maintaining the temperature at about 90.degree. After the addition is complete, keep the temperature at 90℃ for 30 minutes.
Then Triton x-200 (Triton x-200) 33.7g
added. The emulsion was cooled to room temperature and filtered through cheesecloth. The actual solid content was 36.5%, compared to the calculated value of 42.4%. Reference Example 11 The production of a styrene-divinylbenzene emulsion copolymer having a fine particle size will be explained. The monomer emulsion was prepared using 90 g of deoxygenated water, Siponate DS-4 (trademark of Alcoholics Inc. for the sodium salt of dodecylbenzenesulfonic acid), 2.73 g.
g, 123.5 g styrene, 72.5 g divinylbenzene (55.2% divinylbenzene, remainder mainly ethylvinylbenzene) and 4.0 g glacial methacrylic acid.
was obtained by stirring vigorously under nitrogen atmosphere. 350 g of water, Siponate DS- in a separate container under nitrogen atmosphere
33.09 g of Siponate DS-4 and 1.0 g of potassium persulfate were stirred and heated to 85°C. While keeping the temperature of the above monomer emulsion at 85℃,
It was added dropwise over an hour and a half. A solution of 0.4 g of potassium persulfate in 75 ml of water was added and the mixture was stirred at 85° C. for 2 hours. The product was cooled to room temperature and filtered through cheesecloth. The actual value of solids content is the calculated value
It was 26.0% compared to 27.0%. Reference Example 12 The production of vinylbenzyl chloride-divinylbenzene emulsion copolymer will be explained.
Potassium persulfate 1.0g, Siponate DS-4
(Siponate DS-4) 35.74g and deoxygenated water 350g
The mixture of g was stirred under nitrogen atmosphere. A mixture of 171 g of vinylbenzyl chloride and 29 g of divinylbenzene (55.2% divinylbenzene, the remainder being mainly ethylvinylbenzene) was added. The mixture was cooled to 0-10°C and nitrogen was bubbled through for 2 hours. A solution of 1.0 g of potassium persulfate in 50 g of water was added and the temperature was raised to 30° C. for 18 hours. Add a solution of 0.48 g of sodium bicarbonate in 20 g of water for 6 to 24 hours.
The temperature was raised to ℃. The product was cooled to room temperature and filtered through cheesecloth. The actual value of solids content is
It was 29.6% compared to the calculated value of 31.8%. Reference Example 13 Brine aggregation of the polymer emulsion obtained in Reference Example 7 will be explained. A 40 g sample of the polymer emulsion obtained in Reference Example 7 was added to 100 ml of a stirred solution of 25% sodium chloride in water at 100°C. It was kept at this temperature for 2 minutes and cooled to 50°C. The solid product was filtered and washed with water and then methanol. The solids content of the water-washed aggregate was 50%. Reference Example 14 Chloromethylation and aminolysis of the copolymer emulsion obtained in Reference Example 10 will be explained. A sample of the copolymer emulsion obtained in Reference Example 10 was agglomerated and dried according to the method of Reference Example 2. A 44.4 g sample of the dried coagulum was swollen in 403 ml of propylene dichloride for 1.5 hours at room temperature. Stir the slurry and chloromethyl methyl ether 80.5
Added ml. The mixture was cooled to 10°C and dissolved in aluminum chloride in 42 ml of chloromethyl methyl ether.
34.5 g of the solution was added dropwise over 20 minutes while maintaining the temperature at 10°C. The mixture was kept at 10°C for 4 hours with stirring and added to 350 ml of water with cooling so that the temperature never rose above 30°C. The reaction mixture was diluted with 250 ml of water and stirred for 30 minutes to allow the phases to separate. The aqueous phase was decanted and the organic layer was washed three times with water in batches, once with 4% caustic soda solution and twice more with water. Approximately 25 of this product
%, 80 ml of 25% aqueous trimethylamine, 3 g of 50% caustic soda solution and 120 ml of water were combined and heated to 65° C. for 3 hours. The temperature was then raised to about 75°C, and the propylene dichloride-water azeotrope was stripped. The material was cooled to 50° C. and nitrogen was passed over the stirring product to remove excess triethylamine. The polymer emulsion product was left overnight and decanted to separate a small residue of settled solids. The solids content of the product is
It was 17%. Reference Example 15 Aminolysis of the chloromethylated styrene-divinylbenzene copolymer coagulum obtained by the method described in Reference Example 5 will be explained. A 20 g sample of the 7% divinylbenzene-styrene copolymer coagulum obtained according to Reference Example 2 was chloromethylated according to the method of Reference Example 5. Propylene dichloride - about 20% swelling product, 100 ml of water and 25 ml of 25% aqueous trimethylamine were stirred at room temperature for 2 hours and heated to 65°C for 5 hours.
heated for an hour. The temperature was raised to 85°C and propylene dichloride and excess trimethylamine were stripped. The solid was filtered and washed with water to give the aminated product. Example 4 The conversion of a hydrolyzed and resuspended methyl acrylate-divinylbenzene emulsion copolymer from its salt form to its free acid form by batch processing using a strong acid ion exchange resin is described. 237.7 g (0.71 equivalents) of the methyl acrylate-divinylbenzene copolymer emulsion sample obtained according to Reference Example 7 was added by the method of Example 1.
Hydrolyzed with 250 g of 12.5% caustic soda solution. The resulting dark homogeneous product is amberlite in H ⁺ form
IR-/20 ion exchange resin (Pennsylvania,
Philadelphia, Rohm and Haas)
A slurry was prepared with 500 ml (0.9 equivalents) and immediately became more fluid. amber light
The IR-120 ion exchange resin beads were filtered and washed with water. The total amount of filtrate and washing liquid is 672g (solid content
It was 9.17% (97% of the theoretical value). The results of trace analysis are as follows. C=55.92% H=6.18% O=34.54% Na=144 ppm Reference Example 16 Amination of the emulsion copolymer coagulum obtained in Reference Example 13 will be explained. The coagulum sample obtained in Reference Example 13 was dried at 110°C, and 4g of the dried solid was heated with 15g of bis(3-dimethylaminopropyl)amine to 230°C for 2 hours. The resulting methanol was removed with a stream of nitrogen. The reaction mixture was diluted with methanol and the coagulum was filtered, washed with methanol and then water, and drained. The solids content of the aminated product was 40% compared to 50% of the water-washed starting material. Reference Example 17 Hydrogen and hydroxyl Amberlite IR-120 and Amberlite IRA-400 ion exchange resins (Rohm & Haas, Philadelphia, Pennsylvania), respectively, of the strong base-functionalized copolymer emulsion obtained according to Reference Example 14. The ion exchange and conversion from chloride form to hydroxide form by column treatment will be explained using a column-based ion exchanger (manufactured by Co., Ltd.). Amberlite in H ⁺ form was added to a 5 ml sample of the strong base-functionalized copolymer emulsion obtained according to Reference Example 14 at a rate of 0.5 bed volumes per hour.
Pass through a column of 8.55 ml of IR-120 ion exchange resin,
The column was washed with deionized water. The effluent was then treated with 7.6 ml of Amberlite IRA-400 ion exchange resin in the OH ^- form at a rate of 0.5 bed volumes per hour.
The column was washed with deionized water in the same manner. A total of 13.1 ml of effluent was collected. A 4 ml sample of this effluent was titrated with 4.35 ml of IN hydrochloric acid to an end point of PH=7. Effluent sample 0.5g and 0.11N hydrochloric acid
0.56 ml was evaporated to dryness to give 0.164 g of solid material, with a calculated hydroxyl form solids content of 2.99%. A titratable strong base capacity of 3.64 meq/g was calculated. Reference Example 18 The production of flocs from a strong acid-functionalized copolymer emulsion and a strong base-functionalized copolymer emulsion is described. An 11 ml sample of a 0.5% solids suspension of a strong base-functionalized copolymer emulsion in the hydroxide form prepared according to Reference Example 5 and resuspended by column treatment with caustic soda as in Example 2 and the reference 9 ml sample of 0.5% solids strong acid functionalized copolymer emulsion prepared according to Example 4 and resuspended as in Example 2.
and shaken together. The result was a solid floc that settled, leaving a clear supernatant liquid. Example 5 The preparation of flocs from weakly acidic and weakly base-functionalized copolymer emulsions is described. A 5 ml sample of a 2.07% solids weakly acidic functionalized copolymer emulsion obtained according to Example 1 and a sample obtained according to Reference Example 6
A 2.5 ml sample of the 3.97% solids weak base functionalized copolymer emulsion was combined and shaken. Deionized water was added and allowed to settle to obtain a solid floc.
The supernatant was hazy. Example 6 The thermal regeneration properties of a floc obtained by combining weak acid and weak base emulsion resins are described. A floc was made according to Example 5, and the amounts of weak base and weak acid resin emulsion were selected to yield a floc of 0.2 g. This floc was placed in 16 ml of water, and while stirring rapidly, the pH was adjusted to 5.6 by adding dilute acid or base as necessary.
Add sodium chloride to the mixture until the concentration of the liquid phase is approx.
100 ppm and the mixture was equilibrated at room temperature. The resistivity was 7200 ohm-cm, corresponding to 70 ppm sodium chloride. While stirring this mixture
Heat to 92°C and equilibrate to that temperature. Stop stirring and let the floc settle while maintaining the temperature.
A portion of the supernatant was transferred to a conductivity cell. This sample was cooled to room temperature and its resistivity was measured.
Equivalent to 102 ppm sodium chloride at 4900 ohm-cm. The supernatant liquid of the sample was added back to the original mixture and the entire mixture was then cooled to room temperature. The PH and resistivity were measured again and found to be the same as the initial values at room temperature. This operation was repeated with a second sample of the same floc, again using a representative thermally regenerable hybrid ion exchange resin. The preparation of this ion exchange resin is described in US Pat. No. 3,991,017. The measurement results for these substances are shown in Table 1.

Table: Sample A is a floc obtained as described in Example 6, and Sample B is a representative thermally regenerable hybrid ion exchange resin. Reference Example 19 Strong acid for filtering finely ground suspended solids from water
The uses of strong base flocs will be explained. A floc was prepared according to Reference Example 18, and the amount of strong base and strong acid resin emulsion was adjusted to 79.5 mg of floc containing 47% cationic resin and 53% anionic resin.
was chosen so that it would occur. The floc was placed in a 1/2 inch (1.3 cm) diameter glass tube containing 100 mesh nylon mesh. A room temperature suspension of 300 ppb hematite in water at an inlet pressure of 25 psi (1.70 atm) and flow rate.
3.7 gpm/ft ² (18 ml/min absolute flow rate) into the glass tube. The floc bed pressure differential and the effluent Silting Index were monitored over time. As shown by the silching index, the floc still had sufficient filtration capacity, but the differential pressure
Measurements were stopped when an inlet pressure of 25 psi (1.70 atmospheres) was approached, i.e. after 630 minutes. The results of this measurement are shown in Table 1.

【table】

Table Silching Index is a number determined using a Millipore Silching Index Instrument (Millipore Catalog No. xx6801300) and is based on the time required to transport a given volume of liquid through a 0.45-micron Millpore filter. Silching index is described in Federal Test Method 5350. Reference Example 20 Explains the use of strong acid-strong base flocs for deionization. A floc was prepared according to Reference Example 18, and the amounts of strong base and strong acid resin emulsion were selected to yield 200 mg of floc containing 40% cationic and 60% anionic emulsion resin. The floc was placed in a 1/2 inch (1.3 cm) diameter glass tube containing 100 mesh nylon mesh. Calculated as _CaCO3
Solution containing 9.76ppm NaCl at 25psi inlet pressure
(1.70 atm) Flow rate at room temperature 3.7 gpm/ft ² (18
ml/min absolute flow rate) through a glass tube. The differential pressure between the layers and the resistivity of the effluent were monitored. Breakthrough Effluent Low Efficiency Decrease 4.0
It was defined as the point at which the leakage became megohm-cm (approximately 10% leakage). This leakage occurred in approximately 23.5 minutes and was equal to a calculated capacity of 0.048 g Cl ^- per gram of dry anionic resin. The results of this measurement are shown in Table 1.

【table】

[Table] Reference Example 21 Decolorization of a raw sugar solution washed with water using an emulsion ion exchange resin will be explained. sugar refining equipment
A 125 ml sample of the water-washed raw sugar solution with ICUMSA color 900 and a concentration of 65° Brix was
Heated to 80°C. This was prepared from the emulsion copolymer of Reference Example 1, agglomerated according to Reference Example 2, chlorinated according to Reference Example 14,
And 0.20 g of aminolyzed strong base anion exchange resin emulsion in chloride form on a dry basis.
(equivalent to 2000 parts resin per million parts sugar solids) was added. The mixture was stirred for 5 minutes and then transferred to a pressure filter and filtered through diatomaceous earth supported on coarse filter paper. The sugar solution is quickly filtered and the filtrate is
It was a clear decolorized solution of ICUMSA Color 180. ICUMSA color determination using the modified ICUMSA method 4 can be found in Canne Sugar Handbook, 10th edition, published by John Wiley and Sond.
book)”. The determination of this color is based on a wavelength of 420 nanometers and a measured value of PH.
7.0 and extrapolate the results to 100% sugar concentration. Reference Example 22 A suspension of a floc obtained from a cationic and anionic emulsion resin in an organic solvent will be explained. A 9 ml sample of a strongly acidic emulsion cation exchange resin prepared according to Reference Example 4 and resuspended as a 0.5% solids emulsion according to Example 2 was mixed with a 9 ml sample of a strongly acidic emulsion cation exchange resin prepared according to Reference Example 15 and resuspended as a 0.5% solids emulsion. % aqueous sodium hydroxide solution to the hydroxyl form and mixed with a 11 ml sample of strongly basic emulsion anion exchange resin resuspended as a 0.5% solids emulsion according to Example 2 to form a floc. The floc was transferred to a glass filter funnel, drained, and washed with acetone to replace the water in the floc. This floc was found to retain its cohesive properties in waste water, ie, acetone medium. The floc is then first placed in a nitrogen stream.
Finally, it was dried in an oven at 95°C. The dried flocs were photographed using scanning electron microscopy and were found to have a microporous structure, ie, relatively large void spaces were present within the structure of the aggregated emulsion resin beads. "Effects of the Invention" According to the present invention, weakly acidic cation exchange emulsion copolymer resin particles having the following properties can be provided. (a) regular and highly spherical in shape; (b) a high degree of structural rigidity that can be adjusted by the degree of crosslinking of the emulsion copolymer; (c) an adjustable small particle size whose median value varies between 0.01 and 1.5 micrometers; (d) narrow particle size range, where optical micrograph analysis shows approximately 80% of the particles range primarily within ±9 nanometers about the median particle size; (e) a typical conventional small diameter ion exchange resin. (f) greater surface area per unit weight varying with particle size from about 4 square meters per gram to about 120 square meters per gram compared to about 0.1 square meters per gram for (g) the ability to form emulsions that are virtually non-sedimentable except for the largest particle size; (h) controlled by the degree of crosslinking of the emulsion copolymer, approximately 10% of the dry particle size; (i) water insolubility and negligible water extractability, as well as desirable sensitivity, (j) mild taste, (k) resin compatibility. (l) A texture that is smooth and non-irritating to the mouth, and (m) A texture that is smooth and non-irritating to the skin.

[Brief explanation of drawings]

Figures 1, 2 and 3 each show electron micrographs at a magnification of 50,000 times showing the particle structure of the strongly basic anion exchange emulsion resin in the form of hydroxyl ions, and Figure 4 shows the particle structure of the strongly basic anion exchange emulsion resin in the form of hydroxyl ions. The magnification showing the floc particle structure is (a) 1000 respectively.
(b) 300x, (c) 10,000x, and (d) 3,000x electron micrographs as substitutes for drawings.

Claims (1)

[Scope of Claims] 1. Obtained by emulsion polymerization and having a submicroscopic size and approximately spherical shape with a diameter in the range of 0.01 to 1.5 micrometers and 0.7 to 1.5 micrometers per monomer unit.
A liquid cation exchange material characterized in that it consists of an emulsion of beads of a crosslinked copolymer having cation exchange functional groups composed of the free acid form of weakly acidic functional groups. 2. The liquid cation exchange material of claim 1, wherein the copolymer is an acrylic acid copolymer. 3. The liquid cation exchange material of claim 1, wherein said beads have an average diameter of 0.01 to 0.5 micrometers. 4 Consisting of beads of a crosslinked copolymer obtained by emulsion polymerization, having an approximately spherical shape with a diameter ranging from 0.01 to 1.5 micrometers and having from 0.7 to 1.5 weakly acidic cation exchange groups in free acid form per monomer unit. Weakly acidic cation exchange resin particles characterized by: 5 (a) Emulsion polymerization of a majority of the acrylic acid ester monomer and a small amount of the polyethylenically unsaturated monomer to form crosslinked acrylic acid copolymer beads; (b) removing the ester bonds of the acrylic acid copolymer beads with a strong acid; (c) resuspending the functionalized copolymer bead agglomerate; and (c) resuspending the functionalized copolymer bead agglomerate. forming an emulsion of the functionalized copolymer beads having submicroscopic dimensions and approximately spherical shape with a diameter ranging from 0.01 to 1.5 micrometers and having a diameter of 0.7 per monomer unit. A method for producing a liquid cation exchange material consisting of an emulsion of beads of a crosslinked copolymer having ~1.5 weakly acidic cation exchange functional groups, the weakly acidic groups being in the free acid form. 6 (a) emulsion polymerization of a majority of the acrylic ester monomer and a small amount of polyethylenically unsaturated monomer to form an emulsion of crosslinked acrylic acid copolymer beads; (b) removing the ester bonds of the acrylic acid copolymer beads with alkaline water; (c) contacting the emulsion of the functionalized copolymer beads with a strongly acidic cation exchange resin in the free acid form to effect functionalization in the emulsion; converting the emulsion copolymer beads into the free acid form, having a diameter in the range of 0.01 to 1.5 micrometers and 0.7 per monomer unit.
A method for producing submicroscopic cation exchange resin particles consisting of approximately spherical beads of a crosslinked copolymer having ~1.5 weakly acidic cation exchange functional groups, the weakly acidic groups being in the free acid form. 7 A liquid containing anionic impurities is obtained by emulsion polymerization, has a submicroscopic size and an almost spherical shape with a diameter in the range of 0.01 to 1.5 micrometers, and has a diameter of 0.7 to 1.5 micrometers per monomer unit. A method for the removal of anionic impurities from a liquid containing said impurities, characterized in that it is brought into contact with beads of a crosslinked copolymer having cation-exchange functional groups constituted by the free acid form of acidic functional groups. 8. The method of claim 7, wherein the emulsion is removed after the impurities are removed from the liquid by adding a flocculant to the liquid to form a floc with emulsion particles and then removing the floc from the liquid.