JPS60179410A - Production of highly alcohol-absorptive bead resin - Google Patents

Abstract

PURPOSE:To produce the titled resin free of fine powder and excellent in the absorption rate and absorptivity of an alcohol, by copolymerizing a carboxyl group-containing vinyl monomer with a tert. amino group-containing vinyl monomer and a crosslinking agent. CONSTITUTION:A carboxyl group-containing vinyl monomer [e.g., (meth)acyrilc acid] and a tert. amino group-containing vinyl monomer [e.g., dimethylaminoethyl (meth)acrylate] in a molar ratio of 20:80-80:20 are dissolved in water to form a solution of a concentration of 30-70wt%, and a water-soluble radical polymerization initiator is added to this solution. The resulting aqueous solution is dispersed in an aliphatic hydrocarbon solvent (e.g., hexane) with the aid of a dispersant (e.g., sorbitan monostearate) and the dispersion is copolymerized in the presence of 0.01-5.0wt% crosslinking agent [e.g., N,N-methylenebis(meth)acrylamide].

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides bead-shaped resins that have excellent alcohol absorption capacity (absorption capacity for lower carbon alcohols such as methanol, ethanol, etc.), that is, alcohol absorption speed and alcohol absorption capacity. It relates to a manufacturing method.

In recent years, various superabsorbent resins have been developed for disposable diapers, sanitary napkins, soil water retention agents, etc., which absorb and retain large amounts of water with a small weight. Examples of these resins include starch graft polymers (% Japanese Patent Publication No. 53-45199) and cross-linked polyacrylates (Japanese Patent Publication No. 54-30710).
), but all of them absorb only aqueous solutions and do not have the ability to absorb alcohol. However, resins having alcohol absorption ability are used for solidifying alcohol fuels and alcohol solutions, for example. On the other hand, amphoteric resins have been discovered that have the ability to absorb both alcohol and aqueous solutions (Japanese Unexamined Patent Publication No. 154710/1983).
, an aqueous solution polymerization method is adopted, and therefore the polymerization product becomes a water-containing rubber-like substance, which is followed by a laborious process such as pulverization and drying, and has the drawback of easily producing fine powder. Furthermore, since stirring during polymerization is difficult, it is difficult to remove the polymerization heat, and the polymerization system tends to be non-uniform, resulting in the disadvantage that the physical properties of the product are also likely to become non-uniform.

The inventors of the present invention have overcome the above-mentioned problems and, as a result of intensive study on a method of supplying a product in a preferable product form, have obtained a uniform bead-shaped resin that does not contain fine particles and has excellent alcohol absorption speed and amount. Methodology The present invention has been completed.

That is, the present invention uses a water-soluble radical polymerization initiator,
A vinyl monomer having a carboxyl group (component A) and a vinyl monomer having a tertiary amino group (component B) at a composition ratio of A:B=20:0 to 80:20, and ,A
Component and B component are combined into an aqueous solution with a monomer concentration of 50 wt% or more, which is dispersed or suspended in an aliphatic hydrocarbon solvent in the presence of a dispersant, and copolymerized with a crosslinking agent, or The present invention provides a method for producing a bead-shaped high-density alzole resin, which is characterized by forming a frame after polymerization.

The present invention will be explained in more detail below.

Examples of vinyl monomers having a carboxyl group used in the present invention include (methacrylic acid); examples of vinyl monomers having a quaternary amino group include diethylaminoethyl Cl, acrylate, diethylamino Examples include ethyl (meth)acrylate, dimethylaminopropyl (meth)acrylamide, diethylaminopropyl (meth)acrylamide, dimethylaminomethyl (meth)acrylamide, etc. In the present invention,
The mWi of the monomers is not limited, and a combination of three or more of these monomers may be used. The molar ratio of the vinyl monomer having a carboxyl group to the vinyl monomer having a tertiary abano group can be selected from the range of 20:80 to 80:20 depending on the absorption conditions. From the viewpoint of physical properties, a range of 30:0 to 70:50 is preferable. Furthermore, resins copolymerized with nonionic water-soluble vinyl monomers such as 2-hydroxyethyl (meth)acrylate and acrylamide can also be used in the method of the present invention to the extent that the performance of the alcohol-absorbing resin is not deteriorated. .

The concentration of the monomer aqueous lα in accordance with the A component and the B component as well as the nonionic water-soluble vinyl monomer can be varied within a wide range, and is generally 50 wt% to 70 wt%. This upper limit depends, in particular, on the solubility upon mixing of the polymers on both sides, but the lower limit will generally not be lower than the above-mentioned value for economic reasons.

For polymerization, reverse-phase suspension polymerization is employed, and the monomer aqueous solution containing a water-soluble radical polymerization initiator such as persulfate is mixed with a dispersant in an aliphatic hydrocarbon solvent. Dispersants used in this case include sorbitan fatty acids such as sorbitan monostearate and fulbitan monolaurate, cellulose ethers such as hyethyl cellulose and benzyl cellulose, maleated polybutadiene, maleated polyethylene, etc. Examples include polymeric dispersants, and either one or two or more of these may be used. Furthermore, aliphatic hydrocarbons such as hexane, heptane, and octane, and alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, and decalin can be excluded.

Reverse-phase suspension polymerization has a large deripening effect, so it is easy to obtain a high molecular weight resin, and since it is bead-like and has no fine powder, there is no need to take measures against dust, and it has uniform performance between particles. This method is preferable in terms of product form as an alcohol-absorbing resin because it allows the resin to be obtained. That is, by employing reverse-phase suspension polymerization, it is possible to obtain a resin with excellent absorption properties, especially alcohol absorption rate, and it has become possible to further expand the uses of the resin.

For example, the resin of the present invention can be used as a demethanol agent in the transesterification reaction of methyl ester.

The resin produced according to the present invention is essentially insoluble in alcohol and has the property of absorbing and retaining alcohol, which is different from TF. In order to provide this property, a cross-oxidizing agent is used in its production,
Make it insoluble.

In the present invention, this crosslinking agent must be water-soluble, and must be a compound having two or more functional groups that can react with divinyl compounds, carboxyl groups, or tertiary amino groups that can be crosslinked during polymerization. Either one is fine. A compound having two or more functional groups that can react with a carboxyl group or a tertiary amine group can be added to an aqueous monomer solution to cause crosslinking along with polymerization, but sometimes it reacts with the monomer and becomes insolubilized before polymerization. Therefore, it is preferable to add it after the polymerization is completed. Examples of divinyl compounds include N,N-methylenebis(meth)acrylamide, tetraethylene glycol di(meth)acrylate, decaethylene glycol di(meth)acrylate, etc., which react with carboxyl groups or 6th-class amino groups. Examples of compounds having two or more functional groups that can be used include polyglycidyl ethers such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, and glycerin triglycidyl ether, and haloepoxy compounds such as epichlorohydrin and α-methylchlorohydrin. , polyaldehydes such as geltaraldehyde and glyoxal can be used. Preferably, it is a polyglycidyl ether such as ethylene glycol diglycidyl ether.

The amount of the crosslinking agent varies depending on the type of crosslinking agent and the type of polymer, but it is usually 0.01 to 5.0% with respect to the polymer. Ow
t% is an appropriate range. Amount of crosslinking agent added′hO,0
If the amount is less than 1WZ%, the effect of addition will not be sufficiently expressed,
Upon absorption, the gel becomes semi-dissolved. On the contrary, 5. (l1
If it exceeds wt%, the crosslinking density becomes high and the absorption amount decreases (this is not the intention of the present invention).

The resin obtained according to the present invention has excellent absorption performance for alcohols, especially alcohols with lower carbon numbers, such as methanol, ethanol, etc., but hardly absorbs alcohols with carbon numbers of 5 or more. It has no absorption capacity. Since the resin obtained by the present invention has excellent absorption performance for alcohol, it can be used in fields such as solid fuels and dealcoholization agents for transesterification reactions, as well as agricultural chemicals soluble in γ alcohol,
It is also possible to use the absorbent resin of the present invention as a sustained release base material by impregnating it with medicines, etc., and it can be used in a wide range of applications.

The present invention will be explained in detail below using Examples and Comparative Examples, but the present invention is not limited to these Examples.

In addition, the absorption amount in the following examples and comparative examples is a value determined by the following operation. Approximately 1 g of Ruchi resin was dispersed in a large excess of methanol absorbent liquid, allowed to swell sufficiently, and passed through a wire mesh with 80 meshes of horsetail S, and the weight of the swollen resin (W) obtained was determined to be 6111, This value is obtained by dividing this value by the initial resin weight (WO).

In other words, absorption amount ('/l) = w/wo.

The absorption rate was expressed as the amount of liquid absorbed by 0.3 g of resin in 10 minutes.

Example-1 Stirrer, reflux condenser, dropping port, and nitrogen gas inlet pipe.
[1 500. 230ml of cyclohexane in a 4-necked round bottom flask. Ethyl cellulose N-200 ()
- Curies)+, o, and p were added and the temperature was raised to 75°C. Separately in an Erlenmeyer flask, acrylic acid 1'2.0 &
dimethylabanoethyl methacrylate) 26.29'
Dissolved in R709 distilled water, added 35% sulfuric acid 51, and further added N,N-methylenebisacrylamide 0.05F.
Add r, :,.

0.027 ammonium persulfate was added and dissolved as an initiator, and this monomer aqueous solution was dropwise polymerized into the above-mentioned 4-hole flask under a nitrogen atmosphere for 1.5 hours.
@~75℃ for 0.5 hours to complete 9 polymerization! :
the law of nature. After cooling, cyclohexane was removed and the polymer was heated to 80°C.
Dry under reduced pressure at ~100°C with a median particle size of 100-350.
A bead-like resin gold of μm size was obtained.

Example 2 The preparation method in Example 1 was the same as in Example 1, except that the monomer portion was 20 J' of acrylic acid, 18.7 J' of dimethylaminoethyl methacrylate, and 211 J' of 55% hydrochloric acid. Bead-shaped resin having a center particle size of 100 to 350 μm was obtained.

Example 6 In the charging and reprocessing method in Example 1, acrylic acid B&, dimethylaminoethyl methacrylate) 4 D, 7.9. ．． Using 8g of 55% hydrochloric acid, the central particle size was 100-45 using the same method as Example 1 and my colleague.
The entire resin was made into beads of 0 μm.

Example-4 Polymerization was carried out according to Example-1. However, 1.8 g of sorbitan monostearate was used instead of ethyl cellulose N-200, N,N-methylenebisacrylamide was not added to the monomer aqueous solution, and after the polymerization was completed, 0.05 g of ethylene glycol diglycidyl ether was added.
I' was dissolved in 1 ml of water at a total temperature of 60°C. After keeping the solution at this temperature for 5 hours, cyclohexane was completely removed.
The polymer was dried under reduced pressure at 80 to 100°C to obtain bead-shaped resin having a center particle size of 70 to 250 μm.

E3 Example-5 Practical h (Polymerization was carried out according to Q Example-4.Example-4 except that the monomer portion was 20.9 g of acrylic acid, 20 g of dimethylaminoethyl methacrylate, and 2 g of 55% hydrochloric acid.
The same operation as above was carried out to obtain bead-shaped resin having a center particle size of 70 to 250 μm.

Example 6 Polymerization was carried out in the same manner as in Example 4. Acrylic acid +2.0.9 in the monomer part. Diethylaminoethyl methacrylate (50.9.9) All operations were carried out in the same manner as in Example 4 to obtain bead-shaped resin with a center particle size of 100 to 300 μm.

Example-7 Polymerization was carried out in accordance with Example-1. Except that no hydrochloric acid was added to the monomer aqueous solution, and V-50 (manufactured by Wako Tsumugi Pharmaceutical Co., Ltd., 2,2'-azobis(2-amidinopropane) dihydrochloride) 0.059 total acetic acid was added and dissolved. fruit b1
In the same manner as in Example 1, a bead-bound resin having a center particle size of 100 to 350 μm was prepared.

Comparative Example-1 Acrylic acid 12.0,9. Dimethylaminoethyl methacrylate) 26.217 was dissolved in 7011 distilled water, and 65% sulfuric acid 5I was added. Furthermore, 0.05.9% of N,N-methylenebisacrylamide was added and uniformly dissolved.The aqueous solution was transferred to a SOOMl separable flask equipped with a stirrer, a reflux condenser, and a nitrogen gas inlet tube, and placed under a nitrogen atmosphere. Ammonium persulfate 0.02 as initiator
g', fl' MS was added, the temperature was raised, and the temperature was kept at 70°C.

As the polymerization progresses, the system becomes thicker and eventually becomes unstirable.

When stirring became impossible after 100W, stirring was completely stopped and the mixture was allowed to stand at 50°C for 2 hours, and then cooled to form a rubber-like hydrated polymer. This was dried under reduced pressure at 80° C. to obtain a powdered resin.

Comparative Example-2 Of the charging composition in Example-1, 30% of acrylic acid
, 9, dimethylaminoethyl methacrylate 7I, 6
The same operation was performed except that 5% hydrochloric acid was not diluted to obtain bead-shaped resin having a center particle size of 100 to 650 μm.

Comparative Example-3 Of the charging composition in Example-1, acrylic acid 2p
, dimethylaminoethyl methacrylate 42. f, 3
The same operation was carried out except that 15.9 g of 5% holic acid was added to obtain bead-shaped resin having a center particle size of 100 to 300 μm.

The absorption amount and absorption rate of each resin obtained in Examples 1 to 7 and Comparative Examples 1 to 3 are shown in Table 1. From Table 1, it is clear how the resin obtained by the method of the present invention exhibits excellent performance in absorption 4 and absorption rate for alcohols (especially methanol and ethanol).

Claims (1)

[Claims] 1. Using a water-soluble radical polymerization initiator, a vinyl monomer having a carboxyl group (component A) and a vinyl monomer having a tertiary amino group (Bfi 32 minutes) were mixed in a molar ratio A.
: B = 20:80 to 80:20 composition ratio and an aqueous solution with a monomer concentration containing 50 wt% or more of A component and B component in total, and this is prepared as an aliphatic hydrocarbon-based solution in the presence of a dispersant. A method for producing a bead-shaped high-quality alcoholic resin, which comprises dispersing or suspending it in a solvent, copolymerizing it with a crosslinking agent, or crosslinking it after polymerization.