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CN-121992519-A - Regenerated cellulose nanofiber with three-dimensional network structure and preparation method and application thereof

CN121992519ACN 121992519 ACN121992519 ACN 121992519ACN-121992519-A

Abstract

The invention discloses regenerated cellulose nanofiber with a three-dimensional network structure, and a preparation method and application thereof, and belongs to the technical field of cellulose nanofiber preparation. The method comprises the steps of (1) preparing modified cellulose, (2) dissolving the modified cellulose in an alkali solution with a certain concentration to obtain a cellulose solution, (3) preparing a coagulating bath solution, adding the coagulating bath solution into the cellulose solution to obtain regenerated cellulose, and (4) treating by a physical means to obtain regenerated cellulose nanofiber. The invention combines cellulose modification, cellulose regeneration and mild homogenization technology together to develop a novel method for preparing the regenerated cellulose nanofiber, which has the advantages of easy operation, low homogenization pressure, low energy consumption, mass production and the like, and the prepared regenerated cellulose nanofiber has the characteristics of superfine diameter and three-dimensional network structure and has excellent suspension performance.

Inventors

  • ZHANG QIANG
  • LIU XIAODI
  • KANG SHUHUA
  • Xia Ruicai

Assignees

  • 华东师范大学

Dates

Publication Date
20260508
Application Date
20241107

Claims (10)

  1. 1. The regenerated cellulose nanofiber with the three-dimensional network structure is characterized in that the regenerated cellulose nanofiber with the three-dimensional network structure is a network structure formed by interweaving a plurality of cellulose nanofibers instead of being in a single form on a microscopic scale, and has the structural characteristics similar to a natural three-dimensional network structure formed by bacterial cellulose, and the regenerated cellulose nanofiber with the three-dimensional network structure has more excellent suspension performance, shearing thinning behavior and emulsifying performance.
  2. 2. A method for preparing regenerated cellulose nanofibers with a three-dimensional network structure, comprising the steps of: (1) Preparing modified cellulose; (2) Dissolving the modified cellulose in an alkali solution with a certain concentration to obtain a cellulose solution; (3) Preparing a coagulating bath solution, and adding the coagulating bath solution into the cellulose solution obtained in the step (2) to obtain regenerated cellulose; (4) Centrifuging and desalting the regenerated cellulose obtained in the step (3), and treating by using a physical means to obtain the regenerated cellulose nanofiber.
  3. 3. The method according to claim 2, wherein in the step (1), the chemical modification method for preparing the modified cellulose comprises phosphorylation, sulfonation, TEMPO oxidation, carboxymethylation modification.
  4. 4. The method according to claim 3, wherein the modified cellulose produced by the TEMPO oxidation method has an oxidation degree of 0.02 to 0.8 and/or the modified cellulose produced by the carboxymethylation modification method has a substitution degree of 0.02 to 1.0.
  5. 5. The method of claim 2, wherein in step (2), the alkaline solution comprises one or more of NaOH, liOH, csOH, ca (OH) 2 .
  6. 6. The method according to claim 2, wherein in the step (2), the concentration of the alkali solution is 1wt% to 20wt%, and/or the mass ratio of the alkali solution to the modified cellulose is 1 (2.5 to 40).
  7. 7. The method according to claim 2, wherein in the step (3), the coagulation bath solution comprises one or more of a hydrochloric acid solution, an acetic acid solution, a sulfuric acid solution, an ethanol/water solution, and an acetonitrile solution, and/or the concentration of the coagulation bath solution is 1wt% to 20wt%, and/or the mass ratio of the coagulation bath solution to the cellulose solution is 1 (1-20).
  8. 8. The method according to claim 2, wherein in the step (4), the physical means comprises mechanical disc grinding, high-pressure homogenizer, micro-jet, steam explosion.
  9. 9. The method according to claim 8, wherein the pressure of the high-pressure homogenizer is 100 to 1200bar.
  10. 10. Use of regenerated cellulose nanofibers according to claim 1, or of the preparation method according to any one of claims 2-9, in daily cosmetics, food and beverage, pharmaceutical slow release.

Description

Regenerated cellulose nanofiber with three-dimensional network structure and preparation method and application thereof Technical Field The invention belongs to the technical field of nano-cellulose preparation, and particularly relates to a preparation method of regenerated cellulose nano-fibers with a three-dimensional network, and a preparation method and application thereof. Background The cellulose has the advantages of wide sources, good biocompatibility, reproducibility, degradability and the like, and has great significance on green sustainable development, low carbon, environmental protection and the like. The nanocellulose is used as a novel biomass nanomaterial, and is widely applied to the fields of foods, cosmetics, paint coatings, biomedical materials, energy storage materials and the like due to excellent performances such as nanoscale, high specific surface area, high strength, low density and the like. The method for preparing the nano-cellulose mainly comprises a mechanical method, a chemical method, a biological method, a TEMPO oxidation method and an ionic liquid method. The physical method is to cut and fibrillate the fiber by using mechanical equipment to obtain nano-scale cellulose, and common mechanical equipment comprises an ultrasonic cell grinder, a high-pressure homogenizer, a high-pressure micro-jet homogenizer, a beater, a ball mill and the like. The method is environment-friendly, but has high energy consumption. The chemical method mainly utilizes strong acid with high concentration such as sulfuric acid, hydrochloric acid, phosphoric acid and the like to treat cellulose, and a large amount of waste acid is generated in the process. The biological method is to treat cellulose by using biological enzyme, and can prepare the cellulose under milder conditions, but the problems of complex preparation process and long period of the enzyme are also existed. TEMPO oxidation and ionic liquid laws require expensive reagents. In addition, the above methods can all obtain uniform, single nanocellulose, while cellulose nanofibers with three-dimensional network structure, for example, bacterial cellulose is natural nanocellulose with three-dimensional network structure obtained by microbial fermentation, and exhibit unique advantages of low viscosity and high suspension. However, bacterial cellulose production suffers from low yields, high costs, long fermentation periods, etc. The plant-based nanocellulose prepared by Bao Lige company also has a three-dimensional network structure with micro-nano scale, and shows excellent rheological property and suspension property. Therefore, the development of the preparation method of the nanocellulose with the novel three-dimensional network structure has important significance for expanding the performance and application of nanocellulose products. Disclosure of Invention In order to solve the defects in the prior art, the invention provides regenerated cellulose nanofiber with a three-dimensional network structure, and a preparation method and application thereof. The invention innovatively provides a regenerated cellulose nanofiber prepared by combining cellulose modification, cellulose regeneration and mild homogenization technologies, and the regenerated cellulose nanofiber prepared by the invention has an ultrafine three-dimensional network structure. The method is simple to operate, environment-friendly and easy to realize industrialization. In order to achieve the above purpose, the technical scheme of the invention is as follows: The invention provides regenerated cellulose nanofiber with a three-dimensional network structure, which is characterized in that: on the microscopic scale, the cellulose nano-fibers do not exist in a single form, but are in a network structure formed by interweaving a plurality of cellulose nano-fibers, and the structure characteristics of the cellulose nano-fibers are similar to the natural three-dimensional network structure formed by bacterial cellulose, so that the cellulose nano-fibers show more excellent suspension performance, shearing and thinning behaviors, emulsifying performance and the like. The invention also provides a preparation method of the regenerated cellulose nanofiber with the three-dimensional network structure, which comprises the following steps: (1) Preparing modified cellulose; (2) Dissolving the modified cellulose in an alkali solution with a certain concentration to obtain a cellulose solution; (3) Preparing a coagulating bath solution, and then adding the coagulating bath solution into the cellulose solution obtained in the step (2) to obtain regenerated cellulose; (4) Centrifuging and desalting the regenerated cellulose obtained in the step (3), and treating by using a physical means to obtain the regenerated cellulose nanofiber. In the present invention, in the step (1), the method for preparing the modified cellulose includes, but is not limited to, chemical modification methods s