KR102290930B1 - Method of preparing inorganic hydrogel nanocomposites capable of self-healing - Google Patents

Abstract

The present invention relates to a method for producing a self-healing inorganic hydrogel nanocomposite, and more specifically, to a method for producing a self-healing inorganic hydrogel nanocomposite, including the steps of: preparing an aqueous solution in which an acrylic monomer and a peroxide initiator are dissolved; adding inorganic flakes to the prepared aqueous solution; and reacting the aqueous solution to which the inorganic flakes are added at a predetermined temperature for a predetermined time.

Description

Method of preparing inorganic hydrogel nanocomposites capable of self-healing

The present invention by self-healing is directed to a method of manufacturing the inorganic hydrogel nanocomposite possible, using molybdenum disulfide (MoS ₂₎ as the inorganic material, and wherein, molybdenum disulfide (MoS ₂₎ is acting as a reducing agent of the redox reaction an acrylic monomer To grow into a polymer and serve as a reversible cross-linking agent that connects polymer chains, and relates to a method for producing an inorganic hydrogel nanocomposite capable of self-healing of the hydrogel.

Since the development of PHEMA (Poly(2-hydroxyethyl methacrylate)) hydrogels in the 1960s, hydrogels have received continuous attention in the field of biomaterials due to their high hydrophilicity and biocompatibility.

Hydrogel refers to a structure in which a hydrophilic polymer is crosslinked by a physical and chemical method to have a three-dimensional network structure, and can be swelled by absorbing a large amount of water to a certain level without being dissolved in a solvent.

Since the water-swelled hydrogel has a moisture content similar to that of cells or tissues, it is widely used in the field of biomaterials.

In addition, because it has a porous structure, it is used as a medium for drug delivery and cell delivery. Stimulus-sensitive hydrogels can be made in a short time by changing the sol-gel by various external stimuli such as pH or temperature, so they are mainly injected. It is used as a drug delivery system.

On the other hand, natural polymers such as gelatin and chitosan are actively used in bioresearch because they have high biocompatibility.

However, in the case of a natural polymer hydrogel, which is commonly studied, it has remarkably low mechanical strength and brittleness, so there are limitations in its application.

Currently, in order to improve the mechanical strength of the polymer hydrogel, research using nanomaterials such as carbon nanotubes or graphene as a filler for the hydrogel is being conducted.

However, in the case of graphene, it is difficult to expect a dramatic improvement in hydrogel strength because it cannot be uniformly mixed with a polymer having a linear structure and has difficulty in water dispersion.

The self-healing method for producing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention was devised to solve the above problems, and first _{, using molybdenum disulfide (MoS 2} ) as an inorganic material, oxidation for polymerization of an acrylic monomer It promotes radical formation by inducing reduction initiation and provides a non-covalent cross-linking point that leads to the formation of a homogeneous complex, allowing easy and rapid single-step radical polymerization without external stimulation (e.g., pH, heat or light) or additional chemical cross-linking agents. An object of the present invention is to provide a method for producing a hydrogel nanocomposite capable of producing a hydrogel.

In addition, another object of the present invention is to provide a method for preparing a hydrogel nanocomposite having all the characteristics of a typical hydrogel and having improved malleability and mechanical strength compared to conventional chemically crosslinked hydrogels.

In addition, the present invention provides a method for producing a hydrogel nanocomposite having self-healing ability to restore the cleaved hydrogel to maintain the mechanical properties before cleavage by having the reversible property of non-covalent cross-linking It is another object. .

On the other hand, the objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned will be clearly understood by those skilled in the art from the following description.

The method for producing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention comprises the steps of preparing an aqueous solution in which an acryl-based monomer and a peroxide initiator are dissolved, and adding inorganic flakes to the prepared aqueous solution in order to achieve the above objects. and reacting the aqueous solution to which the inorganic flakes are added at a predetermined temperature for a predetermined time.

Preferably, the acrylic monomer may be acrylamide, and the peroxide initiator may be potassium persulfate (KPS).

Preferably, the inorganic flakes are MoS ₂ , and the inorganic flakes may be added in an amount of 0.02 to 0.67 wt% based on the total wt%.

Preferably, in the step of reacting the aqueous solution to which the inorganic flakes are added at a predetermined temperature for a predetermined time, the reaction may be performed at 25° C. for 48 hours.

The method for producing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention has the following excellent effects.

First, by using molybdenum disulfide (MoS ₂ ) as an inorganic material to induce redox initiation for polymerization of acrylic monomers to promote radical formation, and to provide a non-covalent crosslinking point that leads to the formation of a uniform complex, external stimulation (for example, Hydrogels can be prepared easily and quickly through single-step radical polymerization without pH, heat or light) or additional chemical crosslinking agents.

In addition, the present invention has all of the characteristics of a typical hydrogel, and at the same time has superior malleability and mechanical strength than a conventional chemically cross-linked hydrogel.

In addition, the present invention has an excellent effect of having the self-healing ability to restore the cleaved hydrogel to maintain the mechanical properties before cleavage by having the reversible property of non-covalent cross-linking.

1 is an overall process diagram of a method for manufacturing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of the main reaction of the method for preparing the inorganic hydrogel nanocomposite shown in FIG. 1 .
3 is an image (a) showing the gelation test result for the formation of a _{MoS 2} -containing composite hydrogel through redox initiation and a graph showing the mechanical properties of the hydrogel nanocomposite according to the _{MoS 2 content (b: compressive stress strain curve)} , c: compressive elastic modulus at 60% strain of hydrogel, d: compressive stress change compared to control group).
4 is a graph showing the results of a kinetic test of the formation of a hydrogel complex according to an embodiment of the present invention.
5 is an image confirming the radical generation by _{MoS 2} and KPS using bromophenol blue (BPB: bromophenol blue).
6 is a graph showing the XPS analysis results for the phase transition of _{MoS 2} induced by redox polymerization.
7 is an image showing the microstructure of the hydride complex (MoS _{2 , 0.08 wt%) after redox initiation.}
8 is a graph showing the mechanical properties of the hydrogel composite polymerized under light blocking conditions.
9 is an image and graph showing the results of self-healing characteristics of the hydrogel composite according to an embodiment of the present invention.

The terms used in the present invention have been selected as widely used general terms as possible, but in certain cases, there are also terms arbitrarily selected by the applicant. should be taken into account to understand its meaning.

Hereinafter, the technical configuration of the present invention will be described in detail with reference to preferred embodiments shown in the accompanying drawings.

In this regard, first, FIG. 1 is an overall process diagram of a method for manufacturing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention, FIG. 2 is a main method of manufacturing an inorganic hydrogel nanocomposite shown in FIG. Schematic of the reaction, Figure 3 is an image showing the gelation test results for the formation of a _{MoS 2} -containing composite hydrogel through redox initiation (a) and a graph showing the mechanical properties of the hydrogel nanocomposite according to the _{MoS 2 content (b)} : compressive stress strain curve, c: compressive elastic modulus at 60% strain of hydrogel, d: compressive stress change compared to control group) 5 is an image confirming radical generation by _{MoS 2} and KPS using bromophenol blue (BPB: bromophenol blue), FIG. 6 is an XPS analysis result for the phase transition of _{MoS 2 induced by redox polymerization} Graph, Figure 7 is _{an image showing the microstructure of the hydrogel composite (MoS 2} , 0.08 wt%) after redox initiation, Figure 8 is a graph showing the mechanical properties of the hydrogel composite polymerized under light-blocked conditions, Figure 9 is an image and graph showing the results of self-healing characteristics of the hydrogel composite according to an embodiment of the present invention.

1 and 2, the method for preparing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention includes preparing an aqueous solution in which an acrylic monomer and a peroxide initiator are dissolved (S100).

In this case, as the acrylic monomer, various acrylic monomers may be used, but in an embodiment of the present invention, acrylamide is used.

Meanwhile, the peroxide initiator is an oxidizing agent used to initiate radical polymerization, and in an embodiment of the present invention, potassium persulfate is used as the peroxide initiator.

On the other hand, the potassium persulfate is _{an inorganic compound having a chemical formula of K 2} S ₂ O ₈ , also called potassium peroxide disulfate or KPS, and refers to a white solid material that is rarely soluble in cold water but more soluble in warm water.

On the other hand, the method for producing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention includes adding inorganic flakes to the prepared aqueous solution (S200).

In this case, the inorganic flake according to an embodiment of the present invention is MoS ₂ (molybdenum disulfide).

On the other hand, the _{reason for using the MoS 2} (molybdenum disulfide) in an _{embodiment of the present invention is due to the mechanical or electronic properties of MoS 2} (molybdenum disulfide) by inducing redox initiation for polymerization of acrylamide under mild conditions to radically Hydrogel nanocomposites can be easily prepared through single-step radical polymerization without external stimuli (pH, heat or light) or additional chemical cross-linking agents, as they promote formation and provide non-covalent cross-linking points that lead to the formation of uniform composite materials. Because.

In addition, _{by using the MoS 2} (molybdenum disulfide), it is possible to prepare a hydrogel nanocomposite having superior elasticity and mechanical properties compared to a conventional chemical crosslinking agent.

Meanwhile, in an embodiment of the present invention, 0.02 to 0.67 wt% of the inorganic flake is added based on the total wt%.

The reason for limiting the wt% of the inorganic flakes as described above is that an incomplete hydrogel was formed when _{less than 0.02 wt% of MoS 2 was used, and the hydrogel having more than 0.67 wt% of MoS 2} had no elasticity and was completely compressed. Because there is a problem that does not work.

On the other hand, in an embodiment of the present invention, the method may further include the step of ultrasonically treating the aqueous solution to which the inorganic flakes are added, which is because the inorganic flakes are well dispersed when sonicated under aqueous conditions due to interlayer interaction. .

On the other hand, the method for producing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention includes the step (S300) of reacting an aqueous solution to which the inorganic flakes are added at a certain temperature for a certain time (S300), wherein the inorganic flakes are In the step (S300) of reacting the added aqueous solution at a predetermined temperature for a predetermined time, the reaction is performed at 25° C. for 48 hours.

At this time, under the above reaction conditions, the _{combination of MoS 2} (molybdenum disulfide) and KPS generates a sulfate radical or a hydroxyl radical, which can initiate radical polymerization of acrylamide. In particular, the MoS ₂ (molybdenum disulfide) is additionally Inducing crosslinking without the need for a crosslinking agent yields a single composite hydrogel.

On the other hand, _{a change in the amount of the MoS 2} (molybdenum disulfide) added may change the mechanical properties of the hydrogel nanocomposite.

_{Therefore, in the present invention, the concentration of MoS 2} to form a hydrogel from acrylamide of 2.8M in water (2.5 ml) in the presence of KPS (0.02 mmol) was tested, and the result is shown in (a) of FIG. As shown, it was confirmed that a hydrogel was formed when reacted at 25 ° C. for 48 hours using 0.02 ~ 0.67 wt% MoS _{2 (0.5 ~ 2.5 mg).}

Meanwhile, the test results for the mechanical properties of the hydrogel nanocomposite prepared according to an embodiment of the present invention will be described in detail below with reference to FIGS. 3 (b) to (d).

At this time, the diameter of the cylindrical sample used for the test is 16 mm on average, and the height is 13 mm.

And the elastic modulus was obtained from the initial linear region, and the _{higher the MoS 2} added at a concentration of 0.02 to 0.08 wt%, the higher the elastic modulus was.

It showed properties similar to gelatin or agarose gel.

On the other hand, after exceeding the peak, the elastic modulus gradually decreased and reached 0.03 MPa at 0.67 wt%.

Through this, it can be confirmed that the increase in the cross-linking point caused by _{the added MoS 2 improves the mechanical strength to produce a hydrogel having excellent mechanical properties.}

However, excessive addition of inorganic flakes disturbed the elasticity of the hydrogel network, resulting in a rather weak hydrogel, which is due to the aggregation or re-stacking of the nanosheets in the matrix during polymerization.

Nevertheless, one of all hydrogels is still fully compressible during 85% strain during the load-unload cycle, regardless of the amount of _{MoS 2 .}

On the other hand, when comparing the compressive stress of the hydrogel at a strain of 60%, the present invention could find a similar trend as in the case of the elastic modulus, and the large deformation of the hydrogel was the result of the viscoelastic poly(acrylamide)-based matrix surrounding the inorganic flakes. It can be confirmed that it is due to a non-covalent cross-linking point that enables recombination.

On the other hand, using N,N′methylenebis(acrylamide)(MBA), a control hydrogel was prepared at 60° C. _{without MoS 2} input (orange in FIGS. 3 (c) and (d)).

Referring to the above figure, as the amount of MBA increased from 0.03 to 0.16 wt%, the toughness of the hydrogel increased linearly, and when more than 0.16 wt% of MBA was used, a very hard hydrogel was obtained instead of an elastic hydrogel, This phenomenon is caused by irreversible covalent bonding.

Hereinafter, the tensile test results of the hydrogel nanocomposite prepared according to an embodiment of the present invention will be described in detail.

First, a hydrogel film (size: 40mm x 10mm x 1.3mm) was prepared for this, and the tensile strength of the hydrogel showed the same aspect as the compression test.

This will be described in detail on, the more the amount of MoS ₂ increases the tensile modulus of the hydrogel to 0.08wt%, 0.08wt% MoS ₂ or more when the elastic modulus to be added is reduced.

At this time, the maximum modulus of elasticity was 0.06 MPa, and high elongation (strain to fracture, 1110%; toughness, 0.6 MJm ^-3 ) was exhibited.

Unlike general chemical crosslinking agents, MoS ₂ exists as a hydrogel additive and promotes radical generation and at the same time induces physical crosslinking, and the composite hydrogel provides one-step room temperature preparation.

On the other hand, gelation is has not occurred only in the presence of MoS ₂ is not KPS, which demonstrate that the radical generated by the reaction between MoS ₂ and the KPS play an important role in the formation of a hydrogel network.

In addition, KPS, and instead of the acrylic monomer under the same conditions in the presence of MoS ₂ Commercial linear poly (acrylamide) (Mn, 150 kDa; 200 mg / mL) when mixed with it was unable to obtain a hydrogel, which is the original MoS2 It means that the surface functional group of the has little effect on the non-covalent crosslinking.

Hereinafter, the kinetic test results of the hydrogel nanocomposite prepared according to an embodiment of the present invention will be described in detail with reference to FIG. 4 .

In this regard, first, (a) of FIG. 4 shows _{that after adding various amounts of MoS 2} (0.03 to 0.33 wt%) at 0.1% strain, acrylamide aqueous solution (2.8M) and KPS (0.3 mol% compared to the monomer) is a dynamic time sweep graph, (b) is a rheometer for the control test group without MoS _{2 and for 0.08 wt% MoS 2} measured under the same conditions (closed circles and open circles represent storage and loss modulus, respectively, and are inserted The part shows the temperature change (pink) during gelation), and (c) shows the compressive stress-strain curves (MoS ₂ , 0.08 wt%) measured at different time intervals during gelation, with the inset plotted over time. It shows the change in the elastic modulus according to the

Meanwhile, the measurement results shown in FIG. 4 were measured using an oscillatory rheometer at 1 rad/s and room temperature. Referring to FIG. 4, as the amount of MoS ₂ increased, the storage modulus increased at a faster rate, which resulted in faster gelation of the polymerization solution. it means.

On the other hand, when less than 0.05 wt% of MoS ₂ was used, gelation did not occur properly during the initial 10 minutes, whereas when it exceeded 0.33 wt%, gelation was too fast to measure, estimated by the intersection of the storage and loss modulus. The gelation time decreased exponentially as _{the MoS 2 content increased.}

On the other hand, the formation of a nanocomposite having _{0.08 wt% MoS 2 showing the highest modulus of elasticity was further investigated.}

A gelation point appeared at the intersection of 220 s, indicating that the solution started to have viscoelasticity.

Thereafter, the storage modulus increased exponentially with time (Fig. 4(b) black).

In addition, the temperature change of the solution was measured, and in the initial stage within 10 minutes, the temperature rose rapidly to 48 °C and cooled within a short time, which is probably caused by the Trommsdorff effect as shown in the inset of Fig. 4(b). ,

This indicates the rapid formation of a covalent bond structure. In contrast, the _{control solution without MoS 2} showed only a liquid reaction in that the loss modulus was found to be 1.6 times larger than the storage modulus under the same conditions at 25 ° C during the measurement (Fig. 4). (b) light blue).

This further demonstrates the dual role of _{MoS 2} in forming the hydrogel network in redox radical initiation and concomitant crosslinking.

On the other hand, the change of the compression curve according to the reaction time of the hydrogel _{was monitored after the start of the redox reaction of MoS 2} (0.08 wt%) and KPS (0.3 mol% compared to the monomer), as shown in Fig. 4(c), A type of cylindrical hydrogel exhibiting a low compressive modulus of 0.01 MPa was obtained after 3 minutes from the start of the reaction at 25°C.

After that, the elastic modulus increased rapidly and reached 0.05 MPa within 6 hours (Fig. 4(c)).

Conversely, the toughness representing the energy absorbed by the network ^{gradually increased from 2.4 to 17.4 KJm -3} over 48 hours when measured under 60% strain (Fig. 4(c)).

This means the steady generation of covalent structures and secondary non-covalent structures in _{MoS 2} flakes through radical polymerization.

Meanwhile, referring to FIG. 5 , in the method for preparing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention, radical generation can be confirmed in an aqueous solution in which _{MoS 2 and KPS are mixed.}

In order to confirm the above-mentioned radical generation, bromophenol blue (BPB), which is a color-forming radical indicator that removes free radicals displayed in clear color contrast, was used (see FIG. 5(a)).

On the other hand, referring to FIG. 5 (b), an aqueous solution of the dye (7.8 μM, 2.5 mL) shows the maximum absorption at 590 nm when measured by UV-Vis spectroscopy, and MoS ₂ (0.08 wt) for 6 hours at 25 ° C. %) and KPS (0.02 mmol), the solution became completely colorless to visualize radical formation through redox reaction.

Accordingly, the absorption peak of BPB at 590 nm also disappeared.

At this time, _{it is assumed that electron transfer to KPS from defects such as sulfur vacancies of MoS 2} (unsaturated Mo) on the basal surface or edge occurs under aqueous conditions, which are mainly transferred to water and generate sulfuric acid radicals together with hydroxyl radicals.

In contrast, single addition of each component did not change the color of the BPB solution as expected, indicating the absence of radicals.

On the other hand, _{after adding MoS 2} , a slight decrease in absorption intensity was found, which is due to the physical adsorption of the chromophore on the surface of the inorganic flakes.

On the other hand, the KPS-containing sample showed no color change even at 25 °C, but once heated to 60 °C, the measurement solution became easily transparent due to thermal decomposition of KPS to form free radicals.

On the other hand, referring to FIG. 6 showing the XPS analysis results for the phase transition of _{MoS 2 induced by redox polymerization, the initial bulk MoS 2} has Mo 3d peaks at 233.2 and 230.1 eV and S 2p at 164.2 and 162.9 eV after deconvolution. peak, indicating a semiconducting 2H phase.

On the other hand, considering that XPS peaks corresponding to Mo 3d (232.2 and 229.3 eV) and S 2p (163.7 and 162.3 eV) appeared, trace amounts of metal 1T phase were also confirmed, and based on the comparison of Mo 3d peaks, 5% was estimated as

On the other hand, addition of KPS slightly increased the amount of 1T phase after radical initiation.

This means that radical species generated during electron transfer can not only be tightly bound to the surface of _{MoS 2} due to the interaction with the substrate, which can stabilize reactive radical intermediates, but also induce atomic plane glide.

This planar glide induced a phase transition and formed a 10% 1T phase as indicated in the center of FIG. 6 .

Redox polymerization of acrylamide significantly induced a phase transition, and thus the 1T phase increased to 45%, showing a red shift of the binding energy of _{MoS 2 (bottom of FIG. 5).}

It is considered that the surface-bound radicals provide a physical crosslinking point and _{form a hydrogel network where intramolecular interactions or steric hindrances between polymer chains cause internal transformation and promote the phase transition of MoS 2} , and C 1 at 288 eV after reaction A specific XPS peak occurs for , indicating the formation of a poly(acrylamide) network.

_{In contrast, the phase of MoS 2} did not change in the control sample with molded poly(acrylamide) without composite hydrogel formation, further demonstrating the importance of radical adsorption and sequential polymerization.

On the other hand, _{referring to FIG. 7, which is an image showing the microstructure of the hydrogel complex (MoS 2} , 0.08 wt%) after redox initiation, when freeze-dried at 0 ° C. for 48 hours, the dried network is a typical hydrogel network. It was found to have an overall porous structure as

The pore diameter ranged from 0.6 to 2 μm as measured by SEM (see Fig. 7(a)).

On the other hand, MoS ₂ flakes were further confirmed after polymerization through TEM (see Fig. 7 (b)).

On the other hand, when preparing the test sample, the acrylamide aqueous solution (0.3M, 2.5mL) was intentionally diluted to disturb the overall gelation, and then the same amount of MoS ₂ (0.08wt%) and KPS (0.02mmol) as previously used. ) was added.

After stirring at 25 °C for 48 h and washing vigorously by filtration, individual flakes covered with poly(acrylamide) could be observed, indicating that crosslinking mainly occurred in _{MoS 2 nanoplates for hydrogel network formation.}

On the other hand, referring to FIG. 8, which is a graph showing the mechanical properties of the hydrogel composite polymerized under a condition in which light is blocked, the hydrogel exhibiting the same mechanical properties when reacted for 48 hours at 25° C. under dark conditions in which the semi-container is blocked with foil could be obtained.

This means that radical formation by light does not significantly affect hydrogel formation.

Meanwhile, different types of monomers were tested to form various complex hydrogels.

As a test example for this, a very soft hydrogel was prepared using N,N-dimethyl acrylamide (DMA) at a concentration of 200 mg/mL. much lower than the value.

It is presumed that acrylamide, which induces high-efficiency hydrogen bonding, resulted in stronger composite hydrogels when polymerized compared to DMA.

Copolymerization of the same concentration of 1:1 acrylamide-DMA (w/w) in water also formed hydrogels.

The modulus of elasticity was found to be an average of 0.02 MPa, which was between the values of the individual hydrogels indicating the inclusion of the two components.

Meanwhile, the self-healing properties of the hydrogel composite according to an embodiment of the present invention will be described in detail below with reference to FIG. 9 .

First, a hydrogel nanocomposite film was prepared similarly using _{0.08 wt% MoS 2} and 0.02 mmol KPS for self-healing characterization, and then cut in half.

The cut hydrogel film was cut into 2.75 cm × 0.8 cm × 0.1 cm, respectively, and further immersed in distilled water for 1 hour to remove residual monomer and peroxide initiator.

For visual clarity, one film was briefly immersed in a methylene blue (0.2 mM, 10 mL) solution to dye blue, and then briefly washed again with water.

After heat treatment at 70 °C for 3 hours, it was confirmed that the ends of the two films were fixed to each other due to the inherent elasticity and reversibility of physical crosslinking in the network.

The change in length of the self-healing and fixed film was negligible (less than 8%), and properties similar to those of the sample film before cutting were shown as shown in FIG. 9(a).

On the other hand, the heating process was considered essential to induce the healing properties of the hydrogel composite by increasing the mobility of the polymer chain and promoting the exchange of the physical cross-linking point on _{the MoS 2 sheet.}

The diffusion of some of the dye molecules to the other cleaved side shows that the two cleaved films self-heal through internal exchange of physical cross-linking points at the interface during the heating process.

On the other hand, the elastic modulus and ultimate strength of the cured hydrogel were recovered by 70% and toughness by 83%.

On the other hand, the maximum strain at the fracture was measured to be similar, which means that some defects or pinholes were formed during the healing process, which resulted in a slight decrease in the mechanical strength of the sample.

However, the self-healing film was still as malleable as the film before cutting, which could be repeatedly stretched over 800% by hand without showing structural defects (see Fig. 9(c)).

On the other hand, after preparing two cut control hydrogel films (MBA. 0.16 wt%) showing similar mechanical performance as a control, the same heat treatment process was performed.

However, the control film did not show self-healing properties by heating, which is an important result revealing the decisive role of _{MoS 2 capable of exchanging physical crosslinking points.}

Moreover _{, the interface between the composite film containing MoS 2} and the control film was not bonded to each other because bond exchange was not made.

As a result, in the method for producing a self-healing inorganic hydrogel nanocomposite according to an embodiment of the present invention, first, an inorganic molybdenum disulfide (MoS ₂ ) is used to induce redox initiation for polymerization of acrylic monomers to form radicals. By providing a non-covalent cross-linking point leading to the formation of a homogeneous complex and promoting there is.

In addition, the present invention has all of the characteristics of a typical hydrogel, and at the same time has superior malleability and mechanical strength than a conventional chemically cross-linked hydrogel.

In addition, the present invention has an excellent effect of having the self-healing ability to restore the cleaved hydrogel to maintain the mechanical properties before cleavage by having the reversible property of non-covalent cross-linking.

As described above, the present invention has been illustrated and described by way of preferred embodiments, but it is not limited to the above-described embodiments, and those of ordinary skill in the art to which the present invention pertains within the scope not departing from the spirit of the present invention Various changes and modifications will be possible.

Claims (6)

preparing an aqueous solution in which an acrylic monomer and a peroxide initiator are dissolved;
adding inorganic flakes to the prepared aqueous solution; and
Including the step of reacting the aqueous solution to which the inorganic flakes are added at a certain temperature for a certain time, wherein the inorganic flakes are MoS ₂ , and the inorganic flakes are characterized in that 0.02 to 0.67 wt% is added based on the total wt% A method for producing a healing inorganic hydrogel nanocomposite.
The method of claim 1,
The method for producing a self-healing inorganic hydrogel nanocomposite, characterized in that the acrylic monomer is acrylamide.
3. The method according to claim 1 or 2,
The method for producing a self-healing inorganic hydrogel nanocomposite, characterized in that the peroxide initiator is potassium persulfate (KPS).
3. The method according to claim 1 or 2,
The step of reacting the aqueous solution to which the inorganic flakes are added at a certain temperature for a certain time is a method for producing a self-healing inorganic hydrogel nanocomposite, characterized in that the reaction is performed at 25° C. for 48 hours.
delete delete

Images