WO2017039392A1 - Method for manufacturing super absorbent polymer fiber - Google Patents

Abstract

The present invention relates to a method for manufacturing a super absorbent polymer fiber, comprising the steps of: manufacturing a neutralization solution by dissolving a water-soluble ethylene-based unsaturated monomer in an aqueous sodium hydroxide solution; adding a crosslinking agent to the neutralization solution and stirring the same so as to prepare a spinning solution; and injecting the spinning solution into a spinneret, carrying out centrifugal spinning, and then drying the same, and to a super absorbent polymer fiber which, as a novel form of a fiber prepared therefrom having a super absorbent polymer function, has flexibility, thereby being applicable to various fields.

Description

Manufacturing method of super absorbent polymer fibers

This application claims the benefit of priority based on Korean Patent Application No. 10-2015-0125535 dated September 04, 2015 and Korean Patent Application No. 10-2016-0106096 dated August 22, 2016. All content disclosed in the literature is included as part of this specification.

The present invention relates to a method for producing superabsorbent polymer fibers.

Super Absorbent Polymer (SAP) is a synthetic polymer material capable of absorbing water of 500 to 1,000 times its own weight.It has been put into practical use as a sanitary device and is now a paper diaper for children. In addition to sanitary products such as gardening soil repair, civil engineering, construction indexing material, seedling sheet, freshness keeper in the food distribution field, and it is widely used as a material for steaming. Therefore, Super Absorbent Polymer (SAP), which is known to have an excellent absorbing capacity compared with conventional absorbents, has a wider range of applications and thus has a high market value.

Current superabsorbent polymers are manufactured and used in powder form. Such superabsorbent polymers in powder form may be scattered or leaked in the manufacture of hygiene materials or in actual use, and are limited in the range of use because they must be used with a specific type of substrate. In addition, the superabsorbent polymer powder manufacturing process is complicated and there are many factors to be controlled.

In order to solve the problems of the prior art as described above, the present invention provides a new type of fiber having a super absorbent polymer (Super Absorbent Polymer) function, and thus, unlike the superabsorbent polymer in the form of powder, There is no risk of scattering or leaking in the application, and the process can be streamlined because it can be spun directly onto the substrate during manufacture. It is also an object of the present invention to provide a method for producing a superabsorbent polymer fiber having a wide range of applications because of its flexibility.

The present invention to achieve the above object,

(1) preparing a neutralizing solution by dissolving a water-soluble ethylenically unsaturated monomer in an aqueous sodium hydroxide solution;

(2) preparing a spinning solution by adding and stirring a crosslinking agent to the neutralizing solution; And

(3) putting the spinning solution into a spinneret and centrifugal spinning and then drying to prepare a superabsorbent polymer fiber;

The neutralization degree of the neutralizing solution is characterized in that 40 to 90 mol%, provides a method for producing a super absorbent polymer fibers.

The present invention also provides a superabsorbent polymer fiber produced by the above production method.

The manufacturing method of the superabsorbent polymer fiber according to the present invention is simplified in the construction of equipment by using centrifugal spinning, low energy consumption, less limit of the polymer that can be spun, and can be simplified in the form of non-woven fabric can simplify the process There is an advantage. In addition, unlike the powdered superabsorbent polymer, it is a new type of fiber that has a super absorbent polymer function, and there is no fear of scattering or leaking when applied as a product in the form of a nonwoven fabric, and can be directly spun onto a substrate during manufacture. Therefore, the process can be simplified and the flexibility can be used to manufacture a superabsorbent polymer fiber having a variety of advantages, there is an advantage that can be expanded to new applications.

1 is a photograph of a super absorbent polymer fiber (nonwoven fabric) according to an embodiment of the present invention.

2 is a scanning electron micrograph of a super absorbent polymer fiber (nonwoven fabric) according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention,

(1) preparing a neutralizing solution by dissolving a water-soluble ethylenically unsaturated monomer in an aqueous sodium hydroxide solution;

(2) preparing a spinning solution by adding and stirring a crosslinking agent to the neutralizing solution; And

(3) putting the spinning solution into a spinneret and centrifugal spinning and then drying to prepare a superabsorbent polymer fiber;

The neutralization degree of the neutralizing solution relates to a method for producing superabsorbent polymer fibers, characterized in that 40 to 90 mol%.

First, the method for producing superabsorbent polymer fibers according to the present invention undergoes a step of preparing a neutralizing solution by dissolving a water-soluble ethylenically unsaturated monomer in an aqueous sodium hydroxide solution in step (1).

In the method for producing superabsorbent polymer fibers according to the present invention, the water-soluble ethylenically unsaturated monomer is not particularly limited as long as it is a monomer normally used in the production of superabsorbent polymers, but preferably anionic monomers and salts thereof and nonionics. Any one or more selected from the group consisting of a hydrophilic containing monomer, an amino group-containing unsaturated monomer, and a quaternized product thereof can be used. Specifically, isobutylene, acrylic acid, polyacrylic acid, methacrylic acid, maleic anhydride, fumaric acid, crotonic acid, itaconic acid, 2-acryloylethanesulfonic acid, 2-methacryloylethanesulfonic acid, 2- (meth) acrylic acid Anionic monomers and salts thereof of loylpropanesulfonic acid or 2- (meth) acrylamide-2-methylpropane sulfonic acid; (Meth) acrylamide, N-substituted (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, methyl acrylate, hydroxypropyl methacrylate, methoxy Nonionic hydrophilic-containing monomers of polyethylene glycol (meth) acrylate or polyethylene glycol (meth) acrylate; And an amino group-containing unsaturated monomer of (N, N) -dimethylaminoethyl (meth) acrylate or (N, N) -dimethylaminopropyl (meth) acrylamide and a quaternized product thereof. It is more preferable that it is at least one selected from the group consisting of isobutylene, maleic anhydride, polyacrylic acid, acrylic acid, methyl acrylate, and hydroxypropyl methacrylate. Most preferably, acrylic acid or salts thereof may be used, and in the case where acrylic acid or salts thereof is used as a monomer, there is an advantage in that a superabsorbent polymer fiber having improved water absorption can be obtained. On the other hand, in the method for producing superabsorbent polymer fibers according to the present invention, the concentration of the water-soluble ethylenically unsaturated monomer may be selected and used appropriately in consideration of reaction time and reaction conditions, but preferably with respect to the total weight of the sodium hydroxide aqueous solution. The content of the water-soluble ethylenically unsaturated monomer may be 10 to 50% by weight. When the concentration of the water-soluble ethylenically unsaturated monomer is less than 10% by weight, it is disadvantageous in terms of economy, and when it exceeds 50% by weight, the viscosity becomes high so that the spinning solution is not spun through the spinneret and thus cannot form a fibrous phase.

In addition, the neutralization degree of the neutralization solution prepared in step (1) is preferably set to 40 to 90 mol%, more preferably set to 50 to 80 mol%. The degree of neutralization referred to in the present invention is a value calculated by an equation calculated at the time of measuring the water-soluble component, and as the value of the degree of neutralization decreases, the absorbency of the final superabsorbent polymer fibers may be reduced.

The present invention may be subjected to a step of preparing a spinning solution by adding a crosslinking agent to the neutralizing solution obtained in step (1) and stirring in step (2).

If the crosslinking agent added in this invention is a compound which can react with the functional group which a polymer has, there is no limitation in the structure. As said crosslinking agent, Preferably, in order to improve the characteristic of the superabsorbent polymer fiber produced, a polyhydric alcohol compound; Acrylate compound; Epoxy compounds; Polyamine compounds; Haloepoxy compound; Condensation products of haloepoxy compounds; Oxazoline compounds; Mono-, di- or polyoxazolidinone compounds; Cyclic urea compounds; Polyvalent metal salts; And it can use 1 or more types chosen from the group which consists of an alkylene carbonate compound, It is more preferable to use an epoxy compound.

Specifically, examples of the polyhydric alcohol compound include mono-, di-, tri-, tetra- or polyethylene glycol, monopropylene glycol, 1,3-propanediol, dipropylene glycol, 2,3,4-trimethyl-1,3 -Pentanediol, polypropylene glycol, glycerol, polyglycerol, 2-butene-1,4-diol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, and One or more types selected from the group consisting of 1,2-cyclohexanedimethanol can be used.

In addition, as an example of the acrylate compound, poly (ethylene glycol) diacrylate may be used.

Ethylene glycol diglycidyl ether and glycidol may be used as the epoxy compound, and polyamine compounds may be ethylenediamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentamine, or pentaethylenehexamine. , At least one selected from the group consisting of polyethyleneimine and polyamide polyamine can be used.

As the haloepoxy compound, epichlorohydrin, epibromohydrin and α-methyl epichlorohydrin can be used. In addition, as a mono-, di-, or a polyoxazolidinone compound, 2-oxazolidinone etc. can be used, for example. And as an alkylene carbonate compound, ethylene carbonate etc. can be used. These may be used alone or in combination with each other. On the other hand, in order to improve the efficiency of a crosslinking process, it is preferable to use including at least 1 type of polyhydric alcohol compounds among these crosslinking agents, More preferably, C2-C10 polyhydric alcohol compounds can be used.

The amount of the crosslinking agent added to the surface of the polymer particles by mixing the crosslinking agent as described above may be appropriately selected depending on the kind of the crosslinking agent to be added or the reaction conditions, but is generally added to the total weight of the water-soluble ethylenically unsaturated monomer. 0.001 to 5% by weight, preferably 0.01 to 3% by weight, more preferably 0.05 to 2% by weight relative to the crosslinking agent can be used. When the content of the crosslinking agent is too small, the crosslinking reaction hardly occurs, and when the content exceeds 5% by weight based on the total weight of the water-soluble ethylenically unsaturated monomer, the physical properties of the superabsorbent polymer may be lowered due to the excessive crosslinking reaction.

Thereafter, the present invention may be subjected to a step of preparing a superabsorbent polymer fiber by drying the spinning solution obtained in step (2) in the step (3) into a spinneret and centrifugal spinning.

The centrifugal spinning is a high-speed spinning by placing the molten or solution polymer in a spinneret having a plurality of holes to rotate at high speed and by using the centrifugal force acting at this time to stretch the unsolidified polymer to laminate the solidified fibers in the collector This is a method for producing a nonwoven fabric. The advantages of centrifugal spinning are that the process can be simplified because the equipment is simple, energy consumption is low, there are few restrictions on the polymer that can be used, and it is manufactured in a non-woven form.

In one embodiment of the present invention, the rotational speed during the centrifugal spinning is preferably 3,000 rpm to 15,000 rpm, but is not limited thereto. When centrifugal spinning at the rotational speed, it can be spun directly on the substrate during manufacturing has the advantage of simplifying the process.

Drying in the step (3) may be carried out for 10 to 120 minutes at a drying temperature of 100 to 250 ℃.

On the other hand, the "drying temperature" throughout this specification may be defined as the temperature of the heating reactor including the heat medium and the polymer in the temperature of the heat medium supplied for drying or the drying process. If the drying temperature is less than 100 ° C., the drying time may be too long, and the physical properties of the superabsorbent polymer fibers to be finally formed may be reduced. If the drying temperature is higher than 250 ° C., only the fiber surface is dried excessively to be finally formed. There exists a possibility that the physical property of a super absorbent polymer fiber may fall. Preferably the drying may be carried out at a temperature of 100 ℃ to 250 ℃, more preferably at a temperature of 160 ℃ to 200 ℃.

On the other hand, the drying time is not limited to the configuration, but in consideration of the process efficiency, etc., it may be performed for 10 minutes to 120 minutes, more preferably 20 minutes to 90 minutes. In addition, if the drying method of such a drying step is also commonly used as a drying process, it can be selected and used without limiting its configuration. Specifically, the drying step may be performed by a method such as hot air supply, infrared irradiation, microwave irradiation, or ultraviolet irradiation.

In one embodiment of the present invention, the fiber is preferably a nonwoven fabric, but is not limited thereto.

The superabsorbent polymer fibers according to the present invention can be suitably used for use in hygiene or resin molded articles. Here, the resin molded article may include the resin fiber of the embodiment, or may be made of only this resin fiber.

The use of such disposable resin molded articles is not particularly limited, and may include molded articles used in various fields such as medicine, chemistry, chemicals, food, or cosmetics.

The present invention also relates to a super absorbent polymer fiber produced by the above production method.

Hereinafter, the present invention will be described in more detail with reference to Examples, but embodiments of the present invention disclosed below are exemplified to the last, and the scope of the present invention is not limited to these embodiments. The scope of the invention is indicated in the appended claims, and moreover contains all modifications within the meaning and range equivalent to the claims. In addition, "%" and "part" which show content in a following example and a comparative example are a mass reference | standard unless there is particular notice.

Example

Example 1 Preparation of Super Absorbent Polymer Fibers

100 g of isobutylene / maleic anhydride and 41.5 g of caustic soda (sodium hydroxide) were dissolved in 330 g of water to prepare a solution having a solid content of 30% by weight and a degree of neutralization of 80 mol%. Thereafter, epoxy (Ethylene glycol diglycidyl ether, EX-810) was added to this solution at 0.3 wt% based on isobutylene / maleic anhydride and stirred to completely mix to prepare a spinning solution. 5 g of the spinning solution was added to a spinneret having a hole size of 600 µm, and spun at a rotational speed of 10,000 per minute to collect a sample, and dried at 190 ° C. for 30 minutes to prepare a superabsorbent polymer fiber nonwoven fabric. The prepared nonwoven fabric is shown in FIG. 1.

Example 2 Preparation of Super Absorbent Polymer Fibers

A superabsorbent polymer fiber nonwoven fabric was prepared in the same manner as in Example 1, except that 1 wt% of epoxy was added as the crosslinking agent to isobutylene / maleic anhydride.

Example 3 Preparation of Super Absorbent Polymer Fibers

100 g of polyacrylic acid and 27.8 g of caustic soda (sodium hydroxide) were dissolved in 734.7 g of water to prepare a solution having a solid content of 17.5 wt% and a neutralization of 50 mol%. Thereafter, epoxy (Ethylene glycol diglycidyl ether, EX-810) was added to the solution as a crosslinking agent in an amount of 0.3 wt% based on polyacrylic acid and stirred to completely mix to prepare a spinning solution. 5 g of the spinning solution was added to a spinneret having a hole size of 600 µm and spun at a rotational speed of 5,000 per minute to collect a sample, and dried at 140 ° C. for 30 minutes to prepare a superabsorbent polymer fiber nonwoven fabric.

Example 4 Preparation of Super Absorbent Polymer Fibers

100 g of acrylic acid, methyl acrylate, hydroxypropyl methacrylate copolymer and 27.8 g of caustic soda were dissolved in 383.25 g of water to prepare a solution having a solid content of 25% by weight and a neutralization degree of 50 mol%. Thereafter, epoxy (Ethylene glycol diglycidyl ether, EX-810) was added to the solution as a crosslinking agent in an amount of 0.1 wt% based on the copolymer and stirred to completely mix to prepare a spinning solution. 5 g of the spinning solution was added to a spinneret having a hole size of 600 µm and spun at a rotational speed of 7,000 per minute to collect a sample, followed by drying at 140 ° C. for 30 minutes to prepare a superabsorbent polymer fiber nonwoven fabric.

Comparative Example 1. Preparation of Super Absorbent Polymer Fiber

A superabsorbent polymer fiber nonwoven fabric was prepared in the same manner as in Example 2, except that the solution was spun in a solution having a neutralization degree of 35 mol%.

Comparative Example 2. Preparation of Super Absorbent Polymer Fiber

A superabsorbent polymer fiber nonwoven fabric was prepared in the same manner as in Example 2, except that the solution was spun in a solution having a neutralization degree of 95 mol%.

The variable adjustments of Examples 1 to 4 and Comparative Examples 1 and 2 are shown in the following [Table 1].

	A concentration (% by weight)	B concentration (% by weight)	Neutrality (mol%)	Revolutions per minute	Drying temperature (℃)	Drying time (minutes)
Example 1	30	0.3	80	10,000	190	30
Example 2		One
Example 3	17.5	0.3	50	5,000	140
Example 4	25	0.1	50	7,000	140
Comparative Example 1	30	One	35	10,000	190
Comparative Example 2	30	One	95	10,000	190

A: water-soluble ethylenically unsaturated monomer

B: crosslinking agent

Experimental Example

Experimental Example  1. Evaluation of Physical Properties of Super Absorbent Polymer Fiber Nonwoven Fabric- Conservative ( CRC , centrifugal retention capacity)

The water holding capacity of the superabsorbent polymer fiber nonwoven fabric prepared in Examples 1 to 4 was measured. The measurement of the water retention capacity was based on the EDANA method WSP 241.3. 0.2 g of the prepared superabsorbent nonwoven fabric was placed in a tea bag and precipitated in 0.9% saline solution for 30 minutes. After dehydration for 3 minutes at 250G (gravity) centrifugal force was measured the amount of saline solution absorbed.

Experimental Example  2. Evaluation of Properties of Super Absorbent Polymer Fiber Nonwoven Fabric- Pressurized Absorption  ( AUL , Absorption Under Load)

The pressure absorbing ability of the superabsorbent nonwoven fabric prepared in Examples 1 to 4 was measured. The measurement of the pressure absorption capacity was based on the EDANA method WSP 242.3. 0.16 g of the sample in the prepared superabsorbent nonwoven fabric was placed in a cylinder defined by EDANA, and a pressure of 0.3 psi was applied to the piston and the weight. Then, the amount of 0.9% saline absorbed for 60 minutes was measured.

	Water retention capacity (g / g)	Pressurized Absorption Capacity (g / g)
Example 1	61.6	7.6
Example 2	24.4	22.2
Example 3	18.5	17.9
Example 4	19.7	19.2
Comparative Example 1	16.3	16.7
Comparative Example 2	22.5	20.4

Experimental Example 3. Scanning electron microscope (SEM) analysis

Figure 2 of the present invention is a SEM analysis to observe the state of the superabsorbent polymer fibers produced by the Example, was measured using a Phenom Pro model of PHENOM WORLD's table SEM. As a result of enlarging the superabsorbent polymer fibers, the width of one fiber was measured to be 4.89 µm.

From the above results, it can be seen that the superabsorbent polymer fibers according to the present invention are a new type of fiber having a super absorbent polymer function having a distribution range of various water-retaining capacity and pressure-absorbing capacity.

Claims (12)

1) preparing a neutralizing solution by dissolving a water-soluble ethylenically unsaturated monomer in an aqueous sodium hydroxide solution;

2) preparing a spinning solution by adding and stirring a crosslinking agent to the neutralizing solution; And

3) preparing a superabsorbent polymer fiber comprising the step of spinning the spinning solution into a spinneret and centrifugal spinning and then drying to prepare a superabsorbent polymer fiber;

The neutralization degree of the neutralizing solution is characterized in that 40 to 90 mol%, the method for producing superabsorbent polymer fibers.

The method for producing superabsorbent polymer fibers according to claim 1, wherein the neutralization degree of the neutralization solution is 50 to 80 mol%.

The method of claim 1, wherein the water-soluble ethylenically unsaturated monomer is isobutylene, acrylic acid, polyacrylic acid, methacrylic acid, maleic anhydride, fumaric acid, crotonic acid, itaconic acid, 2-acryloylethanesulfonic acid, 2-methacryloyl Anionic monomers and salts thereof of ethanesulfonic acid, 2- (meth) acryloylpropanesulfonic acid, or 2- (meth) acrylamide-2-methylpropane sulfonic acid; (Meth) acrylamide, N-substituted (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, methyl acrylate, hydroxypropyl methacrylate, methoxy Nonionic hydrophilic-containing monomers of polyethylene glycol (meth) acrylate or polyethylene glycol (meth) acrylate; And an amino group-containing unsaturated monomer of (N, N) -dimethylaminoethyl (meth) acrylate or (N, N) -dimethylaminopropyl (meth) acrylamide and a quaternized product thereof. The manufacturing method of the superabsorbent polymer fiber.

The super absorbent polymer of claim 1, wherein the water-soluble ethylenically unsaturated monomer is at least one selected from the group consisting of isobutylene, maleic anhydride, polyacrylic acid, acrylic acid, methyl acrylate, and hydroxypropyl methacrylate. Method of making fibers.

The method according to claim 1, wherein the crosslinking agent is a polyhydric alcohol compound; Acrylate compound; Epoxy compounds; Polyamine compounds; Haloepoxy compound; Condensation products of haloepoxy compounds; Oxazoline compounds; Mono-, di- or polyoxazolidinone compounds; Cyclic urea compounds; Polyvalent metal salts; And at least one selected from the group consisting of alkylene carbonate compounds, a method for producing superabsorbent polymer fibers.

The said crosslinking agent is an epoxy compound, The manufacturing method of the super absorbent polymer fiber of Claim 1 characterized by the above-mentioned.

The method of claim 1, wherein the rotational speed during the centrifugal spinning is 3,000 rpm to 15,000 rpm.

The method for preparing superabsorbent polymer fibers according to claim 1, wherein, in step (1), a neutralizing solution is prepared by including 10 to 50% by weight of the water-soluble ethylenically unsaturated monomer based on the total weight of the aqueous sodium hydroxide solution.

The method according to claim 1, characterized in that in step (2) to prepare a spinning solution comprising 0.001 to 5% by weight of the crosslinking agent relative to the total weight of the water-soluble ethylenically unsaturated monomer.

2. The method of claim 1, wherein the drying in step (3) is carried out at a temperature of 100 to 250 ° C. for 10 minutes to 120 minutes.

The method for producing a super absorbent polymer fiber according to claim 1, wherein the fiber is a nonwoven fabric.

The method for producing superabsorbent polymer fibers according to claim 1, wherein the superabsorbent polymer fibers are used for the production of sanitary materials.

Images