KR20210038095A - Preparation method of acrylic acid ester compound - Google Patents

Abstract

The present invention relates to a method for producing an acrylic acid ester compound. By using acrylic acid as a source for acrylate incorporation, it is possible to provide a safe and less toxic production method, and by using acrylic acid, which is a more stable compound, as a reactant, the conversion rate and yield of the acrylic acid ester compound can be improved. In addition, provided is a method for producing a super absorbent polymer having superior performance by using the acrylic acid ester compound produced by the method.

Description

Manufacturing method of acrylic acid ester compound {PREPARATION METHOD OF ACRYLIC ACID ESTER COMPOUND}

The present invention relates to a method for producing an acrylic acid ester compound, and to a technology for providing a safe and low-toxic production method by using acrylic acid as a source for introducing acrylate, and improving the conversion rate and yield of the acrylic acid ester compound. . In addition, it relates to a method for producing a super absorbent polymer having superior performance by using the acrylic acid ester compound prepared by the above method.

Super Absorbent Polymer (SAP) is a synthetic polymer material that has the ability to absorb moisture of 500 to 1,000 times its own weight, and each developer has a SAM (Super Absorbency Material), AGM (Absorbent Gel). Material) and so on. Since the above superabsorbent resin has begun to be put into practical use as a sanitary tool, nowadays, in addition to hygiene products such as paper diapers and sanitary napkins for children, soil repair agents for horticulture, civil engineering, water resistant materials for construction, nursery sheets, freshness maintenance agents in the food distribution field. It is widely used as a material such as, and for poultice.

In most cases, such super absorbent polymers are widely used in the field of sanitary materials such as diapers and sanitary napkins, and for this purpose, it is necessary to exhibit high absorption of moisture, etc., and moisture absorbed by external pressure must not escape. In addition, it is necessary to exhibit excellent permeability by maintaining the shape well even in the state of volume expansion (swelling) by absorbing water.

Therefore, in order for the super absorbent polymer to have excellent performance, the base resin, which is the most important polymer, must have high absorbency.

In order to make such a base resin, in general, by polymerizing an acrylic acid-based monomer in the presence of an internal crosslinking agent, the crosslinking density inside the polymer can be controlled. The internal crosslinking agent is for crosslinking the inside of a polymer in which acrylic acid-based monomers are polymerized, that is, the base resin, and the internal crosslinking density of the base resin can be adjusted according to the type and content of the internal crosslinking agent. If the crosslinking density of the base resin is low, the water absorption capacity is high, but the strength is weak, so there may be a problem that the shape cannot be maintained in the subsequent process.If the crosslinking density is too high, the strength is increased but the water absorption capacity may be lowered, so the strength of the base resin And it is very important to control the appropriate crosslinking density from the viewpoint of absorption capacity.

In general, the internal crosslinking agent used in the super absorbent polymer is a compound containing an acrylic group, and in particular, a diacrylate compound having an acrylic group introduced at both ends of the diol is mainly used. Accordingly, many methods for introducing acrylic into diol are being studied, and in most cases, the trend of using acrylolyl chloride or acrylic anhydride as an acrylate introduction source (Japanese Patent Publication No. 2008-522003).

However, high cost is required to use acryloyl chloride and acrylic anhydride as reactants, and when both materials are used as an acrylate introduction source, there are problems in terms of environment and safety, so mass reaction and mass production are also difficult. .

Japanese Patent Publication No. 2008-522003

The present invention is to provide a method for preparing a safe and less toxic acrylic acid ester compound by using acrylic acid as a source for introducing acrylate, and a method for preparing a super absorbent polymer having superior performance using the prepared acrylic acid ester compound. will be.

In order to solve the above problems, the present invention includes reacting a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3) in the presence of a compound represented by the following formula (4). doing,

It provides a method of preparing an acrylic acid ester compound represented by the following formula (5):

[Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently C _1-20 alkyl,

R ₃ and R ₄ are each independently hydrogen or C _1-20 alkyl,

n is an integer from 1 to 10,

[Formula 2]

In Chemical Formula 2,

R ₅ is hydrogen or methyl,

[Formula 3]

[Formula 4]

In Chemical Formula 4,

R ₆ is substituted or unsubstituted C _1-10 alkylene,

R ₇ to R ₁₀ are each independently a substituted or unsubstituted C _1-10 alkyl,

[Formula 5]

In Chemical Formula 5,

R ₁ to R ₅ and n are as defined in Formula 1 and Formula 2.

In addition, forming an acrylic acid ester compound by the above method;

Crosslinking polymerization of a water-soluble ethylenically unsaturated monomer having at least a partly neutralized acidic group in the presence of the internal crosslinking agent to form a hydrogel polymer;

Drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; And

It provides a method for producing a super absorbent polymer comprising the step of forming a surface crosslinked layer by further crosslinking the surface of the base resin powder in the presence of a surface crosslinking agent.

Hereinafter, the present invention will be described in detail.

In the present specification, the term "substituted or unsubstituted" refers to deuterium; Halogen group; Nitrile group; Nitro group; Hydroxy group; Carbonyl group; Ester group; Imide group; Amino group; Phosphine oxide group; Alkoxy group; Aryloxy group; Alkyl thioxy group; Arylthioxy group; Alkyl sulfoxy group; Arylsulfoxy group; Silyl group; Boron group; Alkyl group; Cycloalkyl group; Alkenyl group; Aryl group; Aralkyl group; Aralkenyl group; Alkylaryl group; Alkylamine group; Aralkylamine group; Heteroarylamine group; Arylamine group; Arylphosphine group; Or it means substituted or unsubstituted with one or more substituents selected from the group consisting of a heterocyclic group containing one or more of N, O, and S atoms, or substituted or unsubstituted with two or more substituents connected among the above-exemplified substituents. . For example, "a substituent to which two or more substituents are connected" may be a biphenyl group. That is, the biphenyl group may be an aryl group or may be interpreted as a substituent to which two phenyl groups are connected.

In the present specification, the alkyl group may be linear or branched, and the number of carbon atoms is not particularly limited, but is preferably 1 to 20. According to an exemplary embodiment, the alkyl group has 1 to 10 carbon atoms. According to another exemplary embodiment, the alkyl group has 1 to 5 carbon atoms. Specific examples of the alkyl group include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, pentyl, n -Pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl , n-heptyl, 1-methylhexyl, cyclopentylmethyl, cycloheptylmethyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2 -Dimethylheptyl, 1-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl, and the like, but are not limited thereto.

In the present specification, the description of the alkyl group described above may be applied except that the alkylene is a divalent group.

Acrylic acid ester compound

The acrylic acid ester compound according to an embodiment of the present invention is represented by Chemical Formula 5.

The acrylic acid ester compound represented by Formula 5 is a thermally decomposable internal crosslinking agent, and the internal crosslinking structure of the polymer obtained by crosslinking polymerization of the compound of Formula 5 and an acrylic acid monomer may be decomposed by heat (for example, at 150°C or higher). have. Accordingly, crosslinking polymerization of the acrylic acid-based monomer in the presence of the acrylic acid ester compound of Formula 5 can provide a crosslinked polymer into which a thermally decomposable internal crosslinked structure is introduced.

Meanwhile, in the above and in the specification of the present invention, "polymer" or "crosslinked polymer" means that an acrylic acid-based monomer is polymerized in the presence of an internal crosslinking agent including the acrylic acid ester compound of Formula 5.

Preferably, R ₁ and R ₂ are each independently, C _1-5 alkyl, R ₃ and R ₄ may each independently be hydrogen or C _1-5 alkyl, most preferably, R ₁ and R ₂ is each methyl, and R ₃ and R ₄ may each independently be hydrogen or methyl.

Preferably, n may be 1 or 2.

Acrylic acid ester compound manufacturing method

In the method for preparing an acrylic acid ester compound according to an embodiment of the present invention, in the presence of the compound represented by Formula 4, the compound represented by Formula 1, the compound represented by Formula 2, and the compound represented by Formula 3 are reacted. It includes the step of making.

Specifically, the preparation method comprises the steps of reacting the compound represented by Formula 2 and the compound represented by Formula 3 in the presence of the compound represented by Formula 4 (step 1); And reacting the product of step 1 with the compound represented by Formula 1 (step 2). As an example, step 1 may be a step of preparing an acrylic acid-acetic acid mixed anhydride, and step 2 may be a step of preparing an acrylic acid ester compound by using the acrylic acid-acetic acid mixed anhydride prepared in step 1 as an acrylate introduction source. .

For example, Step 1 may refer to the following Reaction Scheme 1, and Step 2 may refer to the following Reaction Scheme 2.

[Scheme 1]

[Scheme 2]

In Reaction Schemes 1 and 2, R ₁ to R ₁₀ and n are as defined in Formulas 1 to 5.

The compound represented by Formula 2', which is the product of Scheme 1, is an acrylic acid-acetic anhydride mixed anhydride and is used as an acrylate introduction source for preparing the compound represented by Formula 5 in Scheme 2.

The compound represented by Formula 4 acts as a base in step 1 to make the compound represented by Formula 2 into an acrylate, and the resulting acrylate reacts with the acetic anhydride represented by Formula 3 to be represented by Formula 5. It creates a source of acrylate introduction of the compound.

The introduction source generated in step 1 reacts with a diol containing a tertiary alcohol in step 2 to introduce an acrylate at both ends of the diol, thereby producing a compound represented by Chemical Formula 5.

The reactions of Step 1 and Step 2 may be carried out in the same reactor, and there is no particular limitation on the order of the reactants introduced into the reactor. For example, a compound represented by Formula 2, a compound represented by Formula 3, and a compound represented by Formula 4, which are the reactants of Step 1, are added, and the compound represented by Formula 1 may be added after the reaction is terminated; The reaction may proceed after the reactant of step 1, the compound represented by Formula 2, the compound represented by Formula 3, the compound represented by Formula 4, and the reactant of step 2, the compound represented by Formula 1 are all added; After the compound represented by Formula 1 and the compound represented by Formula 2 are added, the compound represented by Formula 4 may be added, and the compound represented by Formula 3 may be added.

_{In the above production method, R 1} to R ₄ and n of the compound represented by Formula 1 as a reactant are as described in the acrylic acid ester compound.

Preferably, Formula 1 may be any one of the following Formulas 1-1 to 1-4:

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

.

.

In the above production method, the compound represented by Formula 2 is used as a source for introducing acrylate to the terminal of the acrylic acid ester compound of the present invention. In this case, the compound represented by Formula 2 may be preferably acrylic acid.

Conventionally, acryloyl chloride and acrylic anhydride were used as sources of acrylate introduction. However, acryloyl chloride is highly reactive and generates hydrochloric acid gas when it reacts with water. Therefore, toxic hydrochloric acid gas may be generated by moisture in the atmosphere, which may be dangerous to the operator during the manufacturing process. On the other hand, since acrylic acid anhydride reacts with water and is easily decomposed into acrylic acid, its chemical stability is relatively low compared to acrylic acid, and thus it is unsuitable for obtaining a high yield.

However, the compound represented by Chemical Formula 2 has advantages in that it is chemically stable, less toxic, and cheaper than acryloyl chloride and acrylic anhydride. Accordingly, when the compound represented by Formula 2 is used as an acrylate introduction source, mass synthesis and mass production of the acrylic acid ester compound becomes easy.

Preferably, R ₅ may be hydrogen.

In the above preparation method, the compound represented by Formula 3 is acetic anhydride, and reacts with the compound represented by Formula 2 and the compound represented by Formula 4 to produce an acrylic acid-acetic anhydride mixed anhydride. The resulting mixed anhydride is used as a source for introducing acrylate into the diol represented by the formula (1).

In the above preparation method, the compound represented by Formula 4 acts as a base to make the compound represented by Formula 2 into an acrylate. The resulting acrylate reacts with the compound represented by Chemical Formula 3 to produce an acrylic acid-acetic anhydride mixture as an acrylate introduction source.

Preferably, R ₆ is a substituted or unsubstituted C _1-5 alkylene, and more preferably, R ₆ may be ethylene.

Preferably, the R ₇ to R ₁₀ are each independently hydrogen; Or it may be a substituted or unsubstituted C _1-5 alkyl, more preferably, R ₇ to R ₁₀ may each be methyl.

Most preferably, Formula 4 may be N,N,N',N'-tetramethylethylenediamine.

When preparing the acrylic acid ester compound, based on 1 equivalent of the compound represented by Formula 1, the compound represented by Formula 2 may react 3.0 to 5.0 equivalents, and the compound represented by Formula 3 is 1.5 to 3.5 equivalents Can react, and the compound represented by Chemical Formula 4 can react 1 to 3 equivalents.

The conversion rate to the compound represented by Formula 5 by the manufacturing method may be 85 to 99.9%, or 87 to 99.9%, or 90 to 99.9%, or 90 to 99%.

The yield of the compound represented by Formula 5 obtained by the preparation method may be 70 to 95%, or 75 to 95%, or 75 to 90%, or 75 to 87%, or 75 to 85%.

The compound represented by Formula 5 obtained by the above preparation method is not limited thereto, but may be used as a crosslinking agent during polymerization of an acrylic acid-based monomer.

When using the compound represented by Formula 5 as a crosslinking agent compound, for example, forming an acrylic acid ester compound represented by Formula 5, which is a crosslinking agent compound, by the method of the above-described embodiment;

Crosslinking polymerization of a water-soluble ethylenically unsaturated monomer having at least a partly neutralized acidic group in the presence of the internal crosslinking agent to form a hydrogel polymer;

Drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; And

It may include the step of forming a surface crosslinking layer by further crosslinking the surface of the base resin powder in the presence of a surface crosslinking agent.

In this method, after the compound of Formula 5 forms an internal crosslinked structure in a crosslinking polymerization process, a decomposition reaction may be caused by heat treatment in a subsequent further crosslinking process. As a result, the superabsorbent polymer prepared by the above method may have a high surface crosslinking density and gel strength by a high additional crosslinking reaction, and a relatively low controlled internal crosslinking density. Therefore, such a super absorbent polymer exhibits excellent gel strength and pressure absorbency at the same time as well as high absorbency, so that it can be very preferably used for various hygiene materials.

On the other hand, the method for preparing the super absorbent polymer may be in accordance with the conventional method and conditions for preparing a super absorbent polymer disclosed in Japanese Laid-Open Patent Publication No. 2008-522003, except that the crosslinking agent compound prepared by the method of one embodiment is used. .

The method for preparing an acrylic acid ester compound of the present invention increases the conversion rate and yield of the acrylic acid ester compound by using a safe, low toxicity, and chemically stable acrylic acid as an introduction source of acrylate. This facilitates mass synthesis and mass production of acrylic acid ester compounds.

In addition, the method for producing a super absorbent polymer using an acrylic ester compound prepared according to the method for producing an acrylic ester compound of the present invention enables the production of a super absorbent polymer having superior performance.

Hereinafter, it will be described in more detail to aid in understanding the present invention. However, the following examples are merely illustrative of the present invention, and the contents of the present invention are not limited by the following examples.

Preparation Example 1: Preparation of Compound 1

3-methylbutane-1,3-diol (3.1 g, 30 mmol) and acrylic acid (8.6 g, 120 mmol) were added to a 100 ml flask and slowly stirred in an ice bath. TMEDA (7.0 g, 60 mmol) was slowly added to the reaction vessel, paying attention to heat generation, and then the reaction vessel was transferred to a 60° C. oil bath and acetic anhydride (7.7 g, 75 mmol) was added dropwise over 1 hour. Thereafter, the mixture was further stirred at 60° C. for 4 hours, and after confirming that the reaction was terminated through the conversion rate (conversion rate: 99%) of the reaction using TLC and GC, the mixture was extracted three times with n-hexane. After washing the collected hexane layer with water, residual moisture was _{removed with MgSO 4} , filtered and distilled under reduced pressure to obtain compound 1 (3-methylbutane-1,3-diyl diacrylate, yield: 83%).

¹ H NMR (CDCl ₃ , 500 MHz): 6.40-6.28 (m, 2H), 6.11-6.00 (m, 2H), 5.82-5.73 (m, 2H), 4.28 (m, 2H), 2.21 (m, 2H) ), 1.54 (s, 6H)

Preparation Example 2: Preparation of Compound 2

2-methylpentane-2,4-diol (3.5 g, 30 mmol) and acrylic acid (8.6 g, 120 mmol) were added to a 100 ml flask and slowly stirred in an ice bath. TMEDA (7.0 g, 60 mmol) was slowly added to the reaction vessel, paying attention to heat generation, and then the reaction vessel was transferred to a 60° C. oil bath and acetic anhydride (7.7 g, 75 mmol) was added dropwise over 1 hour. Thereafter, the mixture was further stirred at 60° C. for 4 hours, and after confirming that the reaction was terminated through the conversion rate (conversion rate: 95%) of the reaction using TLC and GC, the mixture was extracted three times with n-hexane. After washing the collected hexane layer with water, residual moisture was _{removed with MgSO 4} , filtered and distilled under reduced pressure to obtain compound 2 (2-methylpentane-2,4-diyl diacrylate, yield: 81%).

¹ H NMR (CDCl ₃ , 500 MHz): 6.38 (m, 1H), 6.31 (m, 1H), 6.08 (m, 1H), 6.01 (m, 1H), 5.80 (m, 1H), 5.73 (m, 1H), 5.25 (m, 1H), 1.67 (d, 2H), 1.51 (s, 6H), 1.26 (s, 3H)

Preparation Example 3: Preparation of compound 3

2,5-dimethylhexane-2,5-diol (4.4 g, 30 mmol) and acrylic acid (8.6 g, 120 mmol) were added to a 100 ml flask and slowly stirred in an ice bath. TMEDA (7.0 g, 60 mmol) was slowly added to the reaction vessel, paying attention to heat generation, and then the reaction vessel was transferred to a 60° C. oil bath and acetic anhydride (7.7 g, 75 mmol) was added dropwise over 1 hour. Thereafter, the mixture was further stirred at 60° C. for 4 hours, and after confirming that the reaction was terminated through the conversion rate (conversion rate: 90%) of the reaction using TLC and GC, the mixture was extracted three times with n-hexane. After washing the collected hexane layer with water, residual moisture was _{removed with MgSO 4} , filtered and distilled under reduced pressure to obtain compound 3 (2,5-dimethylhexane-2,5-diyl diacrylate, yield: 75%).

¹ H NMR (CDCl ₃ , 500 MHz): 6.43 (m, 2H), 6.32 (m, 2H), 6.04 (m, 2H), 1.93 (s, 4H), 1.54 (s, 12H)

Preparation Example 4: Preparation of compound 4

4-methylpentane-1,4-diol (3.5 g, 30 mmol) and acrylic acid (8.6 g, 120 mmol) were added to a 100 ml flask and slowly stirred in an ice bath. TMEDA (7.0 g, 60 mmol) was slowly added to the reaction vessel, paying attention to heat generation, and then the reaction vessel was transferred to a 60° C. oil bath and acetic anhydride (7.7 g, 75 mmol) was added dropwise over 1 hour. Thereafter, the mixture was further stirred at 60° C. for 4 hours, and after confirming that the reaction was terminated through the conversion rate (conversion rate: 99%) of the reaction using TLC and GC, extraction was performed three times with n-hexane. After washing the collected hexane layer with water, residual moisture was _{removed with MgSO 4} , filtered and distilled under reduced pressure to obtain compound 4 (4-methylpentane-1,4-diyl diacrylate, yield: 84%).

¹ H NMR (CDCl ₃ , 500 MHz): 6.43 (m, 1H), 6.32 (m, 1H), 6.13 (m, 1H), 6.04 (m, 1H), 5.84 (m, 1H), 5.77 (m, 1H), 4.17 (t, 2H), 1.88 (m, 2H), 1.75 (m, 2H), 1.50 (s, 6H)

Comparative Preparation Example 1

2-methylpentane-2,4-diol (3.5 g, 30 mmol), dichloromethane (30 mL), 4-dimethylaminopyridine (0.4 g, 3 mmol), and Triethylamine (9.1 g, 90 mmol) were added to a 100 mL flask and ice bath It was stirred slowly at. A solution of acryloyl chloride (8.2 g, 90 mmol) and dichloromethane (20 mL) was added dropwise to this reaction vessel over 1 hour. After further stirring at room temperature for 12 hours, the reaction was terminated after checking the conversion rate (85% conversion rate) of the reaction using TLC and GC. The reaction solvent, dichloromethane, was distilled under reduced pressure, and extracted three times with water and n-hexane. Residual moisture in the collected hexane layer was _{removed with MgSO 4} , filtered and distilled under reduced pressure to obtain compound 2 (2-methylpentane-2,4-diyl diacrylate, yield: 62%).

Comparative Preparation Example 2

Add 2-methylpentane-2,4-diol (3.5 g, 30 mmol), toluene (50 mL), 4-dimethylaminopyridine (0.4 g, 3 mmol), and Triethylamine (9.1 g, 90 mmol) in a 100 mL flask and ice bath It was stirred slowly at. Acrylic anhydride (12 g, 90 mmol) was added dropwise to this reaction vessel over 1 hour. Thereafter, the mixture was further stirred at 50° C. for 12 hours, and the reaction was terminated after checking the conversion rate (80% conversion rate) of the reaction using TLC and GC. Toluene, a reaction solvent, was distilled under reduced pressure, and extracted three times with water and n-hexane. Residual moisture in the collected hexane layer was _{removed with MgSO 4} , filtered and distilled under reduced pressure to obtain compound 2 (2-methylpentane-2,4-diyl diacrylate, yield: 52%).

Example 1

Acrylic acid 100 g, 32 wt% caustic soda solution 123.5 g, sodium persulfate 0.2 g as a thermal polymerization initiator, diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (Irgacure TPO) 0.008 g as a photo polymerization initiator , 0.6 g of the compound of Preparation Example 1, 0.18 g of laponite, and 55 g of water were mixed as an internal crosslinking agent to prepare a monomer composition having a total solid content of 43.8% by weight.

The monomer composition was supplied at a rate of 500 to 2000 mL/min on a conveyor belt in which a belt having a width of 10 cm and a length of 2 m rotates at a speed of 50 cm/min. Simultaneously with the supply of the monomer composition, ^{UV rays having an intensity of 10 mW/cm 2} were irradiated to perform polymerization reaction for 60 seconds.

The polymer obtained through the polymerization reaction was cut by a meat chopper method, and dried at 185° C. for 40 minutes using an air-flow oven.

To 100 g of the base resin powder prepared above, a solution of 3.2 g of ultrapure water, 4.0 g of methanol, 0.088 g of ethylene carbonate, and 0.01 g of silica (trade name: REOLOSIL DM30S, manufacturer: Tokuyama Corporation) was administered and mixed for 1 minute, followed by 185 After drying at °C for 90 minutes to perform a surface crosslinking reaction, classification was performed to obtain a super absorbent polymer having a particle diameter of 150 to 850 µm.

Examples 2 to 4

A super absorbent polymer was prepared in the same manner as in Example 1, except that the compounds of Preparation Examples 2 to 4 were used instead of Compound 1 of Preparation Example 1 as an internal crosslinking agent.

Comparative Example 1

A super absorbent polymer was prepared in the same manner as in Example 1, except that 0.6 g of the existing crosslinking agent PEGDA was used instead of Compound 1 of Preparation Example 1 as an internal crosslinking agent.

Experimental Example 1: Conversion and yield of acrylic acid ester compound

Conversion rates and yields were calculated according to Equations 1 and 2 below from the Preparation Examples and Comparative Preparation Examples, respectively, and the results are shown in Table 1 below.

[Equation 1]

Conversion rate (%) = [(number of moles of acrylic acid ester produced before extraction)/(number of moles of the supplied formula 1)]*100

[Equation 2]

Yield (%) = [(number of moles of acrylic acid ester produced after extraction)/(number of moles of formula 1 supplied)]*100

Conversion rate (%) Yield (%) Manufacturing Example 1 99 83 Manufacturing Example 2 95 81 Manufacturing Example 3 90 75 Manufacturing Example 4 99 84 Comparative Preparation Example 1 85 62 Comparative Preparation Example 2 80 52

As can be seen from Table 1, the conversion rate and yield of the manufacturing method according to an embodiment of the present invention were superior to Comparative Preparation Examples 1 or 2 using conventional acryloyl chloride or acetic anhydride as an acrylate introduction source. .

Experimental Example 2: Evaluation of properties of super absorbent polymer

The physical properties of the super absorbent polymers of Examples 1 to 4 and Comparative Example 1 were measured by the following method, and the results are shown in Table 2.

(1) Centrifugal Retention Capacity (CRC)

The water holding capacity of each resin was measured according to EDANA WSP 241.3 by the absorption ratio under no load.

Specifically, from the resins obtained through the Examples and Comparative Examples, respectively, to obtain a resin classified through a sieve of #20-100. This resin W0(g) (about 0.2g) was evenly put in a nonwoven bag and sealed, and then immersed in physiological saline (0.9% by weight) at room temperature. After 30 minutes elapsed, water was removed from the bag for 3 minutes under the condition of 250 G using a centrifuge, and the mass W2 (g) of the bag was measured. Moreover, after performing the same operation without using a resin, the mass W1 (g) at that time was measured. Using each obtained mass, CRC (g/g) was calculated according to the following equation.

[Equation 1]

CRC (g/g) = {[W2(g)-W1(g)]/W0(g)}-1

(2) Absorption under Pressure (AUP)

The absorbency under pressure of 0.7 psi (or 0.3, 0.9 psi) of each resin was measured according to the EDANA method WSP 242.3.

First, when measuring the combined absorption capacity, the resin fraction at the time of the CRC measurement was used.

Specifically, a 400 mesh stainless steel mesh was mounted on the bottom of a plastic cylinder having an inner diameter of 25 mm. The piston that can uniformly spray the water absorbent resin W0(g) (0.16 g) on the wire mesh under the conditions of room temperature and humidity of 50%, and apply an additional load of 0.7 psi (or 0.3, 0.9 psi) evenly thereon. It is slightly smaller than the outer diameter of 25 mm, and there is no gap with the inner wall of the cylinder, and the vertical movement is not disturbed. At this time, the weight W3 (g) of the device was measured.

A glass filter having a diameter of 90 mm and a thickness of 5 mm was placed on the inside of a 150 mm diameter PET dish, and a physiological saline solution composed of 0.9 wt% sodium chloride was at the same level as the upper surface of the glass filter. One sheet of filter paper with a diameter of 90 mm was mounted on it. The measuring device was placed on the filter paper, and the liquid was absorbed for 1 hour under load. After 1 hour, the measuring device was lifted and the weight W4 (g) was measured.

Using each obtained mass, the absorbency under pressure (g/g) was calculated according to the following equation.

[Equation 2]

AUP(g/g) = [W4(g)-W3(g)]/W0(g)

CRC (g/g) 0.7AUP (g/g) Comparative Example 1 32.2 24.9 Example 1 39.1 26.4 Example 2 44.3 24.1 Example 3 51.5 14.1 Example 4 45.7 25.2

When using the internal crosslinking agent prepared by the manufacturing method according to an embodiment of the present invention, compared with Comparative Example 1 using the existing crosslinking agent PEGDA (Polyethylene glycol diacrylate), it exhibits the same level of pressure absorption capacity and excellent level of water holding capacity. I could confirm that.

Claims (14)

Comprising the step of reacting a compound represented by the following formula (1), a compound represented by the following formula (2), and a compound represented by the following formula (3) in the presence of a compound represented by the following formula (4),
Method for producing an acrylic acid ester compound represented by the following formula (5):
[Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently C _1-20 alkyl,
R ₃ and R ₄ are each independently hydrogen or C _1-20 alkyl,
n is an integer from 1 to 10,
[Formula 2]

In Chemical Formula 2,
R ₅ is hydrogen or methyl,
[Formula 3]

[Formula 4]

In Chemical Formula 4,
R ₆ is substituted or unsubstituted C _1-10 alkylene,
R ₇ to R ₁₀ are each independently a substituted or unsubstituted C _1-10 alkyl,
[Formula 5]

In Chemical Formula 5,
R ₁ to R ₅ and n are as defined in Formula 1 and Formula 2.
The method of claim 1,
R ₁ and R ₂ are each independently C _1-5 alkyl,
R ₃ and R ₄ are each independently hydrogen or C _1-5 alkyl,
A method for producing an acrylic ester compound.
The method of claim 1,
R ₁ and R ₂ are each methyl,
R ₃ and R ₄ are each independently hydrogen or methyl,
A method for producing an acrylic ester compound.
The method of claim 1,
n is 1 or 2,
A method for producing an acrylic ester compound.
The method of claim 1,
R ₅ is hydrogen,
A method for producing an acrylic ester compound.
The method of claim 1,
R ₆ is substituted or unsubstituted C _1-5 alkylene,
A method for producing an acrylic ester compound.
The method of claim 1,
R ₆ is ethylene,
A method for producing an acrylic ester compound.
The method of claim 1,
R ₇ to R ₁₀ are each methyl,
A method for producing an acrylic ester compound.
The method of claim 1,
Formula 1 is any one of the following Formulas 1-1 to 1-4,
Preparation method of acrylic acid ester compound:
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

.
The method of claim 1,
Formula 4 is N,N,N',N'-tetramethylethylenediamine,
A method for producing an acrylic ester compound.
The method of claim 1,
Reacting the compound represented by Formula 2 and the compound represented by Formula 3 in the presence of the compound represented by Formula 4 (step 1); And
Including the step of reacting the product of step 1 with the compound represented by Formula 1 (step 2),
Acrylic acid ester compound manufacturing method.
The method of claim 1,
The conversion rate of the reaction is 85 to 99.9%, the yield is 70 to 95%,
Acrylic acid ester compound manufacturing method.
Forming an acrylic acid ester compound by the method of claim 1;
Crosslinking polymerization of a water-soluble ethylenically unsaturated monomer having at least a partly neutralized acidic group in the presence of the internal crosslinking agent to form a hydrogel polymer;
Drying, pulverizing and classifying the hydrogel polymer to form a base resin powder; And
A method for producing a super absorbent polymer comprising the step of forming a surface crosslinked layer by further crosslinking the surface of the base resin powder in the presence of a surface crosslinking agent.
A super absorbent polymer prepared by the method of claim 13.