CN115286815A - Anti-swelling high-strength hydrogel and preparation method thereof - Google Patents

Anti-swelling high-strength hydrogel and preparation method thereof Download PDF

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CN115286815A
CN115286815A CN202210979636.XA CN202210979636A CN115286815A CN 115286815 A CN115286815 A CN 115286815A CN 202210979636 A CN202210979636 A CN 202210979636A CN 115286815 A CN115286815 A CN 115286815A
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hydrogel
salt solution
swelling
strength
solution
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曾小平
柴子铧
周卿云
徐婷秀
周瀚
吴江渝
王大威
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Wuhan Institute of Technology
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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J3/00—Processes of treating or compounding macromolecular substances
    • C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
    • C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
    • C08J3/075—Macromolecular gels
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
    • C08F251/00—Macromolecular compounds obtained by polymerising monomers on to polysaccharides or derivatives thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/16—Halogen-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/28—Nitrogen-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J2351/00—Characterised by the use of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives of such polymers
    • C08J2351/02—Characterised by the use of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives of such polymers grafted on to polysaccharides
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/16—Halogen-containing compounds
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Abstract

The invention belongs to the technical field of high-molecular hydrogel, and discloses an anti-swelling high-strength hydrogel and a preparation method thereof. The preparation method comprises the steps of dissolving water-soluble chitosan, a monomer and a cross-linking agent in water, adding an initiator solution to initiate polymerization to obtain a hydrogel matrix, and sequentially soaking the hydrogel matrix in two salt solutions to finally obtain the anti-swelling high-strength hydrogel. According to the invention, a hydrogel network structure is constructed by taking water-soluble chitosan as a reinforcing component, and a salt solution two-step soaking method is combined, so that the hydrogel has the characteristics of swelling resistance and high strength, the mass of the hydrogel is slightly changed after the hydrogel is fully swelled in a water environment, the compressive strength of the hydrogel can reach 14MPa, the hydrogel does not crack under a large compression ratio condition, and the hydrogel has good stability.

Description

Anti-swelling high-strength hydrogel and preparation method thereof
Technical Field
The invention belongs to the technical field of high-molecular hydrogel, and particularly relates to anti-swelling high-strength hydrogel and a preparation method thereof.
Background
The hydrogel is a high polymer material with a space three-dimensional network structure formed by taking water as a dispersion medium through chemical or physical crosslinking, and is widely applied to the fields of tissue engineering, intelligent skin, flexible electronic devices, sensors and the like because the hydrogel has the advantages of water enrichment, good biocompatibility, controllable physical and chemical properties and the like. In addition, the hydrogel can also simulate the organism tissue environment, so that the hydrogel has great application prospects in the aspects of biomedicine such as drug loading, controllable release, protein separation and purification and the like.
However, the traditional hydrogel has a loose network structure, so that the mechanical property is generally poor, and the traditional hydrogel shows brittle and weak mechanical characteristics under the action of external force, specifically shows low strength (< 0.1 MPa), poor ductility and insufficient toughness, and cannot meet the great increasing desire for the mechanical property in the actual application process at the present stage. Meanwhile, the side group of the hydrogel molecular chain is provided with a hydrophilic group, and the hydrophilic side group and water molecules form hydrogen bonds, so that the hydrogel often has higher water content and can be swelled in water, the swelling behavior can cause the mechanical property of the hydrogel to be greatly reduced, and the application range and the development prospect of the hydrogel are greatly limited.
The natural high molecular polymer is widely used as flexible filler to enhance the mechanical property of the hydrogel due to the characteristics of rich sources, environmental protection, more active functional groups and the like. The chitosan, as the only basic polysaccharide polymer, is also used as a reinforcing component by researchers to improve the mechanical and biological properties of the hydrogel due to its excellent biocompatibility, antibacterial property and strong reactivity. However, general chitosan needs to be dissolved under an acidic condition, so that post-treatment is needed to remove redundant acid in the preparation process of the chitosan-based hydrogel, the synthesis process is complex, the cost is greatly increased, and the problems of high swelling and low strength of the chitosan-based hydrogel are not effectively solved at present.
Therefore, the development of the anti-swelling high-strength hydrogel has good innovation and application value, and is a key point for further expanding the application field of the hydrogel.
Disclosure of Invention
The invention aims to solve the technical problem of the existing hydrogel, and provides an anti-swelling high-strength hydrogel and a preparation method thereof.
In order to solve the technical problem provided by the invention, the invention provides a preparation method of an anti-swelling high-strength hydrogel, which comprises the following steps:
1) Dissolving water-soluble chitosan, a monomer and a cross-linking agent in water to prepare a mixed solution;
2) Dissolving an initiator in water to prepare an initiator solution;
3) Placing the mixed solution in ice-water bath, adding an initiator solution, and performing ultrasonic defoaming to obtain a precursor solution;
4) Heating the precursor liquid to initiate polymerization, and cooling to room temperature to obtain a hydrogel matrix;
5) And (3) soaking the hydrogel matrix in the salt solution A, and then soaking the hydrogel matrix in the salt solution B to obtain the anti-swelling high-strength hydrogel.
In the scheme, the water-soluble chitosan is chitosan oligosaccharide.
In the above scheme, the monomer is acrylic acid or a mixture of acrylic acid and acrylamide, and the mass of acrylic acid accounts for more than 5% of the total mass of the monomer.
In the above scheme, the cross-linking agent is N' N-methylene bisacrylamide.
In the scheme, the mass percentage concentration of the water-soluble chitosan in the mixed solution is 0.5-5%.
In the above scheme, the mass percentage concentration of the monomer in the mixed solution is 15-20%.
In the scheme, the mass ratio of the cross-linking agent to the monomer is (0.1-5): 100.
In the scheme, the initiator is one or more of potassium persulfate and ammonium persulfate.
In the scheme, the mass ratio of the initiator to the monomer is (0.1-5): 100.
In the scheme, the mass percentage concentration of the initiator in the initiator solution is 0.4-9%.
In the scheme, the ultrasonic defoaming time is 0.5-2h.
In the scheme, the heating temperature in the step 4) is 50-60 ℃, and the heating time is 8-18h.
In the above scheme, the cation contained in the salt solution a is a divalent or trivalent metal ion, and the anion contained in the salt solution a is a monovalent acid radical ion.
Further, the divalent metal ion is Ca 2+ 、Mg 2+ 、Zn 2+ Wherein the trivalent metal ion is Fe 3 + 、Al 3+ Wherein the monovalent acid radical ion is Cl - 、NO 3 - One kind of (1).
In the above scheme, the anion contained in the salt solution B is a divalent or trivalent acid ion, and the cation contained in the salt solution B is a monovalent metal ion.
Further, the divalent acid radical ion is SO 4 2- The trivalent acid radical ion is Citrate 3- The monovalent metal ion is Na + 、K + One kind of (1).
In the scheme, the concentration of the salt solution A is 0.2-0.8mol/L.
In the scheme, the concentration of the salt solution B is 0.4-1mol/L.
In the above scheme, the volume ratio of the mass of the hydrogel matrix to the salt solution a is (2.5-3) g:50mL.
In the above scheme, the volume ratio of the mass of the hydrogel matrix to the salt solution B is (2.5-3) g:50mL.
In the scheme, the soaking time of the salt solution A is 2-3h.
In the scheme, the soaking time of the salt solution B is 8-10h.
The invention also provides an anti-swelling high-strength hydrogel which is prepared by the method.
Compared with the prior art, the invention has the beneficial effects that:
1) The invention adopts a salt solution two-step soaking method, realizes high strength by mutual crosslinking of carboxyl on acrylic acid and divalent or trivalent metal cations and mutual crosslinking of amino on chitosan and divalent or trivalent acid radical ions, realizes anti-swelling by recombination of the metal cations and the acid radical anions, ensures that the hydrogel has the characteristics of high strength and anti-swelling property, has the quality changed only a little after being fully swelled in a water environment, has the compressive strength of 14MPa, does not crack under the condition of large compression ratio, and has good stability.
2) According to the invention, the water-soluble chitosan is used as a reinforcing component to construct a hydrogel network structure, water is used as a solvent of the chitosan, a large amount of acid solution is not required to be consumed in the dissolving process, and post-treatment is not required to remove the acid solution in the subsequent process, so that the synthesis process can be greatly simplified, and the synthesis cost is further reduced.
Drawings
FIG. 1 is a graph showing the compressive stress-strain measurements of the anti-swelling high-strength hydrogel prepared in example 1 of the present invention.
FIG. 2 is a graph showing the swelling property test of the anti-swelling high-strength hydrogel obtained in example 1 of the present invention.
FIG. 3 is a graph showing the compressive stress-strain measurements of the anti-swelling high-strength hydrogel obtained in example 2 of the present invention.
FIG. 4 is a graph showing the swelling property test of the anti-swelling high-strength hydrogel obtained in example 2 of the present invention.
Detailed Description
For better understanding of the present invention, the following examples are given for further illustration of the present invention, but the present invention is not limited to the following examples.
The water-soluble chitosan used in the following examples was a chitosan oligosaccharide purchased from Jinhu crustacean GmbH, okinawa county, with a particle size of 100 mesh, a viscosity of 30-50mPa.s, and a degree of deacetylation > 90%.
Example 1
A preparation method of anti-swelling high-strength hydrogel comprises the following steps:
1) Dissolving 0.5g of water-soluble chitosan, 0.364g of acrylic acid, 1.456g of acrylamide and 0.038g of N, N' -methylenebisacrylamide in 9mL of water together to prepare a mixed solution;
2) Dissolving 0.036g of initiator in 1mL of water to prepare an initiator solution;
3) Placing the mixed solution in an ice-water bath, adding an initiator solution into the mixed solution, and performing ultrasonic defoaming for 0.5h to prepare a precursor solution;
4) Heating the precursor liquid to 60 ℃ to react for 18h to initiate polymerization, and cooling to room temperature to obtain a hydrogel matrix;
5) 2.9g of hydrogel matrix was placed in 50mL of 0.2mol/L CaCl 2 Soaking in the solution for 2.5h, and placing in 50mL of 0.4mol/L Na 2 SO 4 Soaking in the solution for 9h to obtain the anti-swelling high-strength hydrogel.
In order to verify the mechanical strength of the anti-swelling high-strength hydrogel prepared in this example, the hydrogel was subjected to a compressive stress-strain test and compressed at room temperature using a universal tester at a compression rate of 20mm/min, and the results are shown in fig. 1, where it can be seen that the sample still remained unbroken when the compression ratio reached 0.85 and the compressive strength reached 13MPa, indicating that the hydrogel prepared in this example has high strength and compressive strength.
In order to verify the swelling resistance of the swelling-resistant high-strength hydrogel prepared in this example, the swelling performance of the hydrogel was tested, the hydrogel was placed in deionized water at an ambient temperature of 25 ℃, the hydrogel was taken out at regular intervals, excess water on the surface was absorbed and weighed, the weight change rate was calculated as the swelling rate, and the results are shown in fig. 2, where it can be seen that the mass of the hydrogel after soaking increased a little and then decreased rapidly, and the final mass decreased only by about 4%, indicating that the hydrogel prepared in this example has good swelling resistance.
Example 2
A preparation method of an anti-swelling high-strength hydrogel comprises the following steps:
1) Dissolving 0.08g of water-soluble chitosan, 0.346 of acrylic acid, 1.864g of acrylamide and 0.108g of N, N' -methylene bisacrylamide in 9mL of water together to prepare a mixed solution;
2) Dissolving 0.004g of initiator in 1mL of water to prepare initiator solution;
3) Placing the mixed solution in an ice-water bath, adding an initiator solution into the mixed solution, and performing ultrasonic defoaming for 2 hours to prepare a precursor solution;
4) Heating the precursor liquid to 55 ℃ to react for 18h to initiate polymerization, and cooling to room temperature to obtain a hydrogel matrix;
5) 2.6g of hydrogel matrix was placed in 50mL of 0.5mol/L Fe (NO) 3 ) 3 Soaking in the solution for 3h, and placing in 50mL of 1mol/L Na 3 And (4) soaking the Cit solution for 8 hours to obtain the anti-swelling high-strength hydrogel.
In order to verify the mechanical strength of the anti-swelling high-strength hydrogel prepared in this example, the hydrogel was subjected to a compressive stress-strain test and compressed at room temperature using a universal tester at a compression rate of 20mm/min, and the results are shown in fig. 3, where it can be seen that the sample still remained unbroken when the compression ratio reached 0.86 and the compressive strength reached 14MPa, indicating that the hydrogel prepared in this example has high strength and compressive strength.
In order to verify the swelling resistance of the swelling-resistant high-strength hydrogel prepared in this example, the swelling performance of the hydrogel was tested, the hydrogel was placed in deionized water at an ambient temperature of 25 ℃, the hydrogel was taken out at regular intervals, excess water on the surface was absorbed and weighed, the calculated weight change rate was the swelling rate, the results are shown in fig. 4, and it can be seen from the figure that the mass of the hydrogel after soaking increased a little and then decreased rapidly, and the final mass decreased only by about 3.9%, indicating that the hydrogel prepared had good swelling resistance.
Example 3
A preparation method of an anti-swelling high-strength hydrogel material comprises the following steps:
1) Dissolving 0.3g of water-soluble chitosan, 0.993g of acrylic acid, 0.988g of acrylamide and 0.065gN, N' -methylenebisacrylamide in 9mL of water together to prepare a mixed solution;
2) Dissolving 0.095g of initiator in 1mL of water to prepare an initiator solution;
3) Placing the mixed solution in an ice-water bath, adding an initiator solution into the mixed solution, and performing ultrasonic defoaming for 1h to prepare a precursor solution;
4) Heating the precursor liquid to 50 ℃ to react for 16h to initiate polymerization, and cooling to room temperature to obtain a hydrogel matrix;
5) 2.7g of hydrogel matrix was placed in 50mL of 0.7mol/L Al (NO) 3 ) 3 Soaking in the solution for 2h, and then placing in 50mL of 0.7mol/L K 2 SO 4 Soaking in the solution for 10h to obtain the anti-swelling high-strength hydrogel.
The above embodiments are merely examples for clearly illustrating the present invention and do not limit the present invention. Other variants and modifications of the invention, which are obvious to those skilled in the art and can be made on the basis of the above description, are not necessarily exhaustive of all embodiments, and are therefore intended to be within the scope of the invention.

Claims (10)

1. A preparation method of an anti-swelling high-strength hydrogel is characterized by comprising the following steps:
1) Dissolving water-soluble chitosan, a monomer and a cross-linking agent in water to prepare a mixed solution;
2) Dissolving an initiator in water to prepare an initiator solution;
3) Placing the mixed solution in ice-water bath, adding an initiator solution, and performing ultrasonic defoaming to obtain a precursor solution;
4) Heating the precursor liquid to initiate polymerization, and cooling to room temperature to obtain a hydrogel matrix;
5) And (3) soaking the hydrogel matrix in a salt solution A, and then soaking the hydrogel matrix in a salt solution B to obtain the anti-swelling high-strength hydrogel.
2. The method for preparing an anti-swelling high-strength hydrogel according to claim 1, wherein said water-soluble chitosan is chitosan oligosaccharide; the mass percentage concentration of the water-soluble chitosan in the mixed solution is 0.5-5%.
3. The method for preparing the anti-swelling high-strength hydrogel according to claim 1, wherein the monomer is acrylic acid or a mixture of acrylic acid and acrylamide, and the mass of acrylic acid accounts for more than 5% of the total mass of the monomer; the mass percentage concentration of the monomer in the mixed solution is 15-20%.
4. The method for preparing an anti-swelling high-strength hydrogel according to claim 1, wherein the cation contained in the salt solution a is a divalent or trivalent metal ion, and the anion is a monovalent acid radical ion; and the anion contained in the salt solution B is divalent or trivalent acid radical ion, and the cation is monovalent metal ion.
5. The method for preparing the anti-swelling high-strength hydrogel according to claim 1, wherein the cation contained in the salt solution A is Fe 3+ 、Al 3+ 、Ca 2+ 、Mg 2+ 、Zn 2+ Wherein the anion is Cl - 、NO 3 - One of (1); the anion contained in the salt solution B is SO 4 2- 、Citrate 3- Wherein the cation is Na + 、K + One kind of (1).
6. The method of claim 1, wherein the ratio of the mass of the hydrogel matrix to the volume of the salt solution A is (2.5-3) g:50mL, the concentration of the salt solution A is 0.2-0.8mol/L, and the soaking time of the salt solution A is 2-3h.
7. The method of claim 1, wherein the ratio of the mass of the hydrogel matrix to the volume of the salt solution B is (2.5-3) g:50mL, wherein the concentration of the salt solution B is 0.4-1mol/L, and the soaking time of the salt solution B is 8-10h.
8. The method for preparing the anti-swelling high-strength hydrogel according to claim 1, wherein the crosslinking agent is N' N-methylenebisacrylamide, and the mass ratio of the crosslinking agent to the monomer is (0.1-5): 100; the initiator is one or more of potassium persulfate and ammonium persulfate, the mass ratio of the initiator to the monomer is (0.1-5): 100, and the mass percentage concentration of the initiator in the initiator solution is 0.4-9%.
9. The method for preparing the anti-swelling high-strength hydrogel according to claim 1, wherein the heating temperature is 50-60 ℃ and the heating time is 8-18h.
10. An anti-swelling, high strength hydrogel prepared by the method of any one of claims 1-9.
CN202210979636.XA 2022-08-16 2022-08-16 Anti-swelling high-strength hydrogel and preparation method thereof Pending CN115286815A (en)

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