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CN-121975149-A - Amination nano-diamond modified tough anti-freezing polyvinyl alcohol hydrogel, preparation method and application

CN121975149ACN 121975149 ACN121975149 ACN 121975149ACN-121975149-A

Abstract

The invention discloses an amination nano-diamond modified tough anti-freezing polyvinyl alcohol hydrogel, a preparation method and application. According to the invention, double-network hydrogel is formed by virtue of the action force of hydrogen bond between polyvinyl alcohol and xanthan gum, free water and intermediate water in the hydrogel are adsorbed by virtue of amino functional groups rich in the surface of the aminated nano-diamond, and the regulation and control of the state of the hydrogel water are realized. The composite hydrogel has high content of bound water, and can obviously improve the toughness and freezing resistance of the hydrogel. The invention provides a general platform for designing the hydrogel with customized low-temperature performance, and opens up a new path for biomedical and engineering application in cold regions.

Inventors

  • FU YONGSHENG
  • SHI LI
  • XIE JIANAN
  • ZHU JUNWU
  • WANG XIN
  • SUN JINGWEN
  • XIONG PAN
  • ZHANG WENYAO
  • HOU ZHEN
  • XUE LIANG

Assignees

  • 南京理工大学

Dates

Publication Date
20260505
Application Date
20260206

Claims (10)

  1. 1. The preparation method of the improved amination nano-diamond modified tough anti-freezing hydrogel is characterized by comprising the following steps of: adding a polyvinyl alcohol matrix and a cross-linking agent into the xanthan gum emulsion containing the aminated nano-diamond, uniformly stirring, performing ultrasonic dispersion, heating to perform a cross-linking reaction, and then freezing and forming the obtained sol at a low temperature to obtain the anti-freezing hydrogel.
  2. 2. The method of claim 1, wherein the concentration of xanthan in the xanthan emulsion comprising the aminated nanodiamond is 3g/L.
  3. 3. The method according to claim 1, wherein the concentration of the aminated nanodiamond in the xanthan emulsion containing the aminated nanodiamond is 1-3 g/L, preferably 2g/L.
  4. 4. The method of claim 1, wherein the cross-linking agent is calcium chloride at a concentration of 2g/L in the xanthan emulsion containing the aminated nanodiamond.
  5. 5. The method of claim 1, wherein the polyvinyl alcohol has an alcoholysis of 98-99% and a concentration of 200g/L in the xanthan emulsion containing the aminated nanodiamond.
  6. 6. The method of claim 1, wherein the resulting sol is frozen at-18 ℃ for 12 hours to yield the freeze resistant hydrogel.
  7. 7. Method according to claim 1, wherein the sol obtained is frozen at-18 ℃ for 12 hours to obtain the freeze-thaw hydrogel, and the freeze-thaw hydrogel is repeated, i.e. the freeze-thaw hydrogel is left at room temperature for 4 hours, and is frozen at-18 ℃ for 4 hours, and the freeze-thawing process is repeated for 1-10 times, preferably 3-5 times.
  8. 8. The method of claim 1, wherein the aminated nanodiamond is prepared by: (1) Adding 1-ethyl- (3-dimethylaminopropyl) carbodiimide into the dispersion, stirring until the mixture is dissolved, dripping ethylenediamine, stirring the mixed solution at 30-40 ℃ for more than 24 hours, and centrifuging; (2) Adding the nano diamond obtained in the step (1) into N, N-dimethylformamide, stirring, ultrasonically dispersing until the nano diamond is uniform, dropwise adding methyl acrylate, stirring the mixed solution at 30-40 ℃ for more than 24 hours, and centrifuging; (3) Adding the nano diamond obtained in the step (2) into N, N-dimethylformamide, stirring, ultrasonically dispersing until the nano diamond is uniform, dripping excessive ethylenediamine, stirring the mixed solution for more than 24 hours at the temperature of 30-40 ℃, centrifugally washing, and freeze-drying to obtain the aminated nano diamond.
  9. 9. An aminated nanodiamond modified tough freeze-resistant hydrogel prepared by the method of any one of claims 1-8.
  10. 10. The aminated nanodiamond modified tough freeze resistant hydrogel of claim 9, wherein the aminated nanodiamond modified tough freeze resistant hydrogel does not freeze at-25 ℃ and remains flexible.

Description

Amination nano-diamond modified tough anti-freezing polyvinyl alcohol hydrogel, preparation method and application Technical Field The invention relates to an improved amination nano-diamond modified tough anti-freezing hydrogel and a preparation method thereof, and belongs to the technical field of hydrogels. Background Along with the expansion of biomedical engineering technology to special environments (such as high altitude, polar region, winter battlefield and disaster rescue sites), the demands for biomedical materials, in particular wound dressing, capable of stably working in low-temperature, dry and severe temperature-changing environments are increasingly urgent. The ideal low-temperature dressing needs to have excellent biocompatibility, flexibility fit, stable moisturizing capability and the characteristics of freezing resistance and function maintenance in an environment below zero. Hydrogels are considered to be a very potential new generation of wound dressing matrix due to their high water content, three-dimensional network structure, good oxygen permeability and gentle properties to the wound surface. Its moist environment can promote wound healing, and the network structure can carry drugs or growth factors. However, conventional hydrogel dressings face a fundamental challenge in low temperature cold region applications, where large amounts of free water within them rapidly form ice crystals below zero. The ice crystals not only damage the integrity of the polymer network, so that the dressing becomes hard, crisp and loses flexibility to be unable to be attached to the wound surface, but also cause secondary mechanical damage to the new tissue due to volume expansion, and the functions of moisturizing, medicine carrying and the like are completely lost. Traditional freezing strategies mainly reduce the freezing point and inhibit ice crystal growth by introducing freezing components such as proteins, organic solvents or ionic compounds, but these methods tend to impair the core advantages of hydrogels at the expense of high water content. While some progress has been made in the prior art, there is less concern about the inherent specificity of the internal water state of hydrogels and their potential as active design parameters. Therefore, it is highly desirable to design a strong hydrogel for controlling the water state in the hydrogel to achieve strong and freeze resistance. Disclosure of Invention Aiming at the defects of the prior art, the primary aim of the invention is to provide an improved amination nano-diamond modified tough anti-freezing hydrogel, and the other aim of the invention is to provide the preparation method of the improved amination nano-diamond modified tough anti-freezing hydrogel. In order to achieve the above purpose, the present invention adopts the following technical scheme: In a first aspect, the invention provides a method for preparing an improved aminated nano-diamond modified tough freeze-resistant hydrogel, which comprises the following steps: adding a polyvinyl alcohol matrix and a cross-linking agent into the xanthan gum emulsion containing the aminated nano-diamond, uniformly stirring, performing ultrasonic dispersion, heating to perform a cross-linking reaction, and then freezing and forming the obtained sol at a low temperature to obtain the anti-freezing hydrogel. Further, the concentration of xanthan in the xanthan emulsion containing the aminated nanodiamond was 3g/L. Further, the concentration of the aminated nano-diamond in the xanthan emulsion containing the aminated nano-diamond is 1-3 g/L, preferably 2g/L. Further, the cross-linking agent was calcium chloride, which was at a concentration of 2g/L in the xanthan emulsion containing the aminated nanodiamond. Further, the alcoholysis degree of the polyvinyl alcohol is 98-99%, and the concentration of the polyvinyl alcohol in the xanthan gum emulsion containing the aminated nano-diamond is 200g/L. Further, the ultrasonic dispersion time is more than 1 min. Further, the crosslinking reaction temperature was 90℃for 60 minutes. Further, the obtained sol is frozen for 12 hours at the temperature of-18 ℃ to obtain the antifreeze hydrogel. Further, the obtained sol is frozen for 12 hours at the temperature of minus 18 ℃ to obtain the freeze-proof hydrogel, the frozen freeze-proof hydrogel is repeatedly frozen and thawed, namely, the freeze-proof hydrogel is placed at room temperature for 4 hours, and is frozen for 4 hours at the temperature of minus 18 ℃, and the freeze-thawing process is repeated for 1 to 10 times, preferably 3 to 5 times. Further, the aminated nanodiamond is prepared by the following steps: (1) Adding 1-ethyl- (3-dimethylaminopropyl) carbodiimide into the dispersion, stirring until the mixture is dissolved, dripping ethylenediamine, stirring the mixed solution at 30-40 ℃ for more than 24 hours, and centrifuging; (2) Adding the nano diamond obtained in the step (1) into N, N-dimethylf