CN113788900B - Modified cellulose nanocrystal with high thermal stability and preparation method thereof - Google Patents
Modified cellulose nanocrystal with high thermal stability and preparation method thereof Download PDFInfo
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- CN113788900B CN113788900B CN202111065435.0A CN202111065435A CN113788900B CN 113788900 B CN113788900 B CN 113788900B CN 202111065435 A CN202111065435 A CN 202111065435A CN 113788900 B CN113788900 B CN 113788900B
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- 239000001913 cellulose Substances 0.000 title claims abstract description 62
- 229920002678 cellulose Polymers 0.000 title claims abstract description 62
- 239000002159 nanocrystal Substances 0.000 title claims abstract description 47
- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 238000006243 chemical reaction Methods 0.000 claims abstract description 10
- 239000007788 liquid Substances 0.000 claims abstract description 10
- 239000006185 dispersion Substances 0.000 claims abstract description 9
- 238000002156 mixing Methods 0.000 claims abstract description 8
- UFMZWBIQTDUYBN-UHFFFAOYSA-N cobalt dinitrate Chemical compound [Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O UFMZWBIQTDUYBN-UHFFFAOYSA-N 0.000 claims abstract description 6
- 229910001981 cobalt nitrate Inorganic materials 0.000 claims abstract description 6
- XTOQOJJNGPEPMM-UHFFFAOYSA-N o-(2-oxo-1,3,2$l^{5}-dioxaphosphinan-2-yl)hydroxylamine Chemical compound NOP1(=O)OCCCO1 XTOQOJJNGPEPMM-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000004729 solvothermal method Methods 0.000 claims abstract description 5
- 238000001816 cooling Methods 0.000 claims abstract description 4
- 238000001035 drying Methods 0.000 claims abstract description 4
- 238000010438 heat treatment Methods 0.000 claims abstract description 4
- 238000000926 separation method Methods 0.000 claims abstract description 4
- 238000005406 washing Methods 0.000 claims abstract description 4
- 238000003756 stirring Methods 0.000 claims description 9
- 239000011259 mixed solution Substances 0.000 claims description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 abstract description 13
- 230000000844 anti-bacterial effect Effects 0.000 abstract description 10
- 238000000034 method Methods 0.000 abstract description 8
- 238000010521 absorption reaction Methods 0.000 abstract description 6
- 229910021529 ammonia Inorganic materials 0.000 abstract description 5
- 230000003321 amplification Effects 0.000 abstract description 3
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 238000003199 nucleic acid amplification method Methods 0.000 abstract description 3
- 239000002086 nanomaterial Substances 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 abstract 3
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical compound CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 description 9
- 241000588724 Escherichia coli Species 0.000 description 3
- 241000191967 Staphylococcus aureus Species 0.000 description 3
- 230000015556 catabolic process Effects 0.000 description 3
- 239000002131 composite material Substances 0.000 description 3
- 238000006731 degradation reaction Methods 0.000 description 3
- 239000003153 chemical reaction reagent Substances 0.000 description 2
- 239000008367 deionised water Substances 0.000 description 2
- 229910021641 deionized water Inorganic materials 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000002329 infrared spectrum Methods 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 238000001000 micrograph Methods 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000002371 ultraviolet--visible spectrum Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- FDGBQHCDMSYZRC-UHFFFAOYSA-N 2-hydroxy-2-oxo-1,3,2$l^{5}-dioxaphosphinan-4-amine Chemical compound NC1CCOP(O)(=O)O1 FDGBQHCDMSYZRC-UHFFFAOYSA-N 0.000 description 1
- 238000010146 3D printing Methods 0.000 description 1
- 230000003385 bacteriostatic effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000012046 mixed solvent Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
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Classifications
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B15/00—Preparation of other cellulose derivatives or modified cellulose, e.g. complexes
- C08B15/02—Oxycellulose; Hydrocellulose; Cellulosehydrate, e.g. microcrystalline cellulose
Abstract
The invention belongs to the technical field of nano materials, and relates to a modified cellulose nanocrystal with high thermal stability and a preparation method thereof. The method comprises the steps of uniformly mixing cobalt nitrate, aminotrimethylene phosphoric acid and cellulose nanocrystal dispersion liquid, then placing the mixture into a reaction kettle, heating the mixture to perform solvothermal reaction, then cooling the mixture to room temperature, performing centrifugal separation, washing and drying to obtain the modified cellulose nanocrystal. The prepared modified cellulose nanocrystal not only has high thermal stability, but also has excellent ammonia response performance, antibacterial performance and ultraviolet absorption performance, and the preparation process is simple, environment-friendly and low in cost, is suitable for amplification production, and has wide application prospects in the fields of gas sensing, environmental safety, biomedical treatment and the like.
Description
Technical Field
The invention belongs to the technical field of nano materials, and particularly relates to a modified cellulose nanocrystal with high thermal stability and a preparation method thereof.
Background
Cellulose Nanocrystals (CNCs) are nano-scale cellulose extracted from natural fibers, have the advantages of rich sources, reproducibility, easy degradation, no toxicity, excellent mechanical properties, excellent optical properties and the like, and are widely applied to the field of composite materials as fillers. Composite materials containing cellulose nanocrystals have been widely used in various fields such as packaging, engineering plastics, biomedical engineering, 3D printing, and the like. However, cellulose nanocrystals have poor thermal stability, which is detrimental to their melt blending with the polymer matrix and the properties of the resulting composite product. It is worth mentioning that the cellulose nanocrystal surface contains a large amount of hydroxyl groups, which are easy to modify, so that the cellulose nanocrystal is expected to improve the thermal stability and endow certain specific functionality (such as ammonia response, antibacterial function, ultraviolet absorption and the like) to the cellulose nanocrystal. The modified cellulose nanocrystalline with high thermal stability and excellent functionality is prepared by a simple and economic method, and has wide application prospect.
Disclosure of Invention
Based on the above background, the present invention provides a modified cellulose nanocrystal with high thermal stability and a preparation method thereof. The modified cellulose nanocrystal provided by the invention has high thermal stability, excellent ammonia response performance, antibacterial performance and ultraviolet absorption performance, and is simple in preparation process, environment-friendly, low in cost and suitable for large-scale production.
The technical scheme of the invention is as follows:
a preparation method of modified cellulose nanocrystalline with high thermal stability comprises the following steps:
(1) dispersing cellulose nanocrystals in a mixed solvent of deionized water and DMF, stirring for 10min, uniformly mixing, adding cobalt nitrate, stirring for 30min to obtain a uniform dispersion liquid, adding aminotrimethylene phosphoric acid into the dispersion liquid, stirring for 40min, and uniformly mixing to obtain a reaction mixed liquid;
(2) and (2) placing the reaction mixed solution obtained in the step (1) into a reaction kettle, heating to carry out solvothermal reaction, then cooling to room temperature, carrying out centrifugal separation, washing and drying to obtain the modified cellulose nanocrystal with high thermal stability.
Preferably, the mass ratio of the cellulose nanocrystals to the cobalt nitrate to the aminotrimethylene phosphoric acid to the deionized water to the DMF in the step (1) is 4: 6: 4: 100: 665.
preferably, the solvothermal reaction temperature in the step (2) is 140 ℃, and the reaction time is 24 h.
The modified cellulose nanocrystal with high thermal stability prepared by the method is provided.
The invention has the following beneficial effects:
the modified cellulose nanocrystal prepared by the method has high thermal stability, excellent ammonia response performance, antibacterial performance and ultraviolet absorption performance, is simple in preparation process, environment-friendly, low in cost, suitable for amplification production, and has wide application prospects in the fields of gas sensing, environmental safety, biomedical treatment and the like.
Drawings
FIG. 1 is a scanning electron microscope image of modified cellulose nanocrystals prepared in accordance with the present invention;
FIG. 2 is an infrared spectrum of unmodified cellulose nanocrystals and modified cellulose nanocrystals prepared in accordance with the present invention;
FIG. 3 is a photograph showing the antibacterial activity of modified cellulose nanocrystals prepared in accordance with the present invention against Escherichia coli;
FIG. 4 is a photograph showing the antibacterial activity of modified cellulose nanocrystals prepared in accordance with the present invention against Staphylococcus aureus;
FIG. 5 is a UV-Vis spectrum of unmodified cellulose nanocrystals and modified cellulose nanocrystal aqueous dispersions prepared in accordance with the present invention.
Detailed Description
The present invention is described in detail below by way of examples, it should be noted that these examples are only for illustrating the present invention and should not be construed as limiting the scope of the present invention, and those skilled in the art can make insubstantial modifications and adjustments to the above-described invention, wherein the raw material parts are in parts by weight unless otherwise specified.
In a specific embodiment, the cellulose nanocrystal (i.e., the unmodified cellulose nanocrystal in the invention) is a product (model number is CNC-C) provided by Guilin Qiji technologies, Inc., and has a diameter of 5 to 20nm and a length of 100 to 500 nm; cobalt nitrate is an analytical pure-grade reagent provided by chemical corporation of Shirong; DMF (N, N-dimethylformamide) is an analytical pure grade reagent provided by chemical corporation, julong; aminotrimethylene phosphate was used as a product provided by Shanghai Michelin Biochemical technology Ltd.
Example (b):
a preparation method of modified cellulose nanocrystals with high thermal stability comprises the following steps:
(1) dispersing 4 parts of cellulose nanocrystals in 765 parts of cellulose nanocrystals according to the mass ratio of 100: 665, stirring for 10min, uniformly mixing, adding 6 parts of cobalt nitrate, stirring for 30min to obtain a uniform dispersion liquid, adding 4 parts of aminotrimethylene phosphoric acid into the dispersion liquid, stirring for 40min, and uniformly mixing to obtain a reaction mixed liquid;
(2) and (2) placing the reaction mixed solution obtained in the step (1) into a reaction kettle, heating to carry out solvothermal reaction at 140 ℃ for 24 hours, then cooling to room temperature, carrying out centrifugal separation, washing and drying to obtain the modified cellulose nanocrystal with high thermal stability.
FIG. 1 is a scanning electron microscope image of a modified cellulose nanocrystal prepared by the present invention, and FIG. 2 is an infrared spectrum of the modified cellulose nanocrystal prepared by the present invention; the results show that the modified cellulose nanocrystals prepared by the present invention have larger particle size and different structures than unmodified cellulose nanocrystals.
The color of the unmodified cellulose nanocrystal is white, and the color is not changed after the unmodified cellulose nanocrystal is exposed in an ammonia gas environment; the color of the modified cellulose nanocrystalline product prepared by the method is bluish purple, and the color of the modified cellulose nanocrystalline product is quickly changed into brown within 1min after the modified cellulose nanocrystalline product is exposed in an ammonia gas environment, so that the modified cellulose nanocrystalline product has excellent ammonia gas response performance.
Evaluating the antibacterial performance of the product by adopting an antibacterial activity experimental method of a bacteriostatic zone; the inhibition zones of the unmodified cellulose nanocrystalline on escherichia coli and staphylococcus aureus are both 0mm, the diameters of the inhibition zones of the modified cellulose nanocrystalline product on the escherichia coli and the staphylococcus aureus can reach 23.5mm and 31mm respectively (see fig. 3 and 4), and the modified cellulose nanocrystalline product is excellent in antibacterial effect.
The thermal stability of the product was evaluated using a thermogravimetric analyzer (SDT-Q600, TA corporation, usa); unmodified cellulose nanocrystals having an initial thermal degradation temperature of 235 ℃; the initial thermal degradation temperature of the modified cellulose nanocrystalline product prepared by the method is 256 ℃, which shows that the modified cellulose nanocrystalline product has obviously improved thermal stability.
Evaluating the ultraviolet-visible performance of the product by adopting an ultraviolet-visible spectrometer (Lamdba365, platinum Elmer instruments Co.); FIG. 5 is a chart of the UV-Vis spectra of unmodified cellulose nanocrystals and modified cellulose nanocrystal aqueous dispersions prepared in accordance with the present invention; the results show that the modified cellulose nanocrystalline product prepared by the method has obviously improved ultraviolet absorption performance compared with unmodified cellulose nanocrystalline.
In conclusion, the modified cellulose nanocrystal prepared by the method disclosed by the invention has high thermal stability, excellent ammonia response performance, antibacterial performance and ultraviolet absorption performance, is simple in preparation process, environment-friendly and low in cost, is suitable for amplification production, and has wide application prospects in the fields of gas sensing, environmental safety, biomedical treatment and the like.
The invention is not limited to the examples, and any equivalent changes to the technical solution of the invention by a person skilled in the art after reading the description of the invention are covered by the claims of the invention.
Claims (1)
1. A preparation method of modified cellulose nanocrystalline with high thermal stability is characterized by comprising the following steps:
(1) dispersing 4 parts of cellulose nanocrystals in 765 parts of cellulose nanocrystals, wherein the mass ratio of the cellulose nanocrystals is 100: 665, stirring for 10min, uniformly mixing, adding 6 parts of cobalt nitrate, stirring for 30min to obtain a uniform dispersion liquid, adding 4 parts of aminotrimethylene phosphoric acid into the dispersion liquid, stirring for 40min, and uniformly mixing to obtain a reaction mixed liquid;
(2) and (2) placing the reaction mixed solution obtained in the step (1) into a reaction kettle, heating to carry out solvothermal reaction at 140 ℃ for 24 hours, then cooling to room temperature, carrying out centrifugal separation, washing and drying to obtain the modified cellulose nanocrystal with high thermal stability.
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| CN202111065435.0A CN113788900B (en) | 2021-09-13 | 2021-09-13 | Modified cellulose nanocrystal with high thermal stability and preparation method thereof |
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| CN113788900B true CN113788900B (en) | 2022-08-09 |
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| CN114409972B (en) * | 2022-01-25 | 2023-05-05 | 桂林理工大学 | Sodium alginate composite material with ammonia response and antibacterial functions and preparation method thereof |
| CN115304685A (en) * | 2022-08-11 | 2022-11-08 | 桂林理工大学 | Modified starch nanoparticles with water resistance, ultraviolet absorption and ammonia response color change functions as well as preparation method and application thereof |
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| CN103435849B (en) * | 2013-08-23 | 2016-03-02 | 华南理工大学 | A kind of cellulose base matrix material for ammonia detection and preparation method thereof |
| CN106279440A (en) * | 2015-05-25 | 2017-01-04 | 中国制浆造纸研究院 | A kind of preparation method of carboxyethylation modified Nano fibrillated fibers element |
| CN106589894B (en) * | 2016-12-19 | 2019-08-27 | 广州简米餐具有限公司 | A kind of preparation method that heat resistance fiber element is nanocrystalline |
| CN106905437B (en) * | 2017-03-20 | 2019-02-26 | 青岛科技大学 | Redispersible powder Cellulose nanocrystal of high heat resistance and preparation method thereof |
| CN112852001B (en) * | 2021-01-08 | 2022-07-26 | 天津科技大学 | Preparation method of nano-cellulose ammonia gas induction aerogel |
| CN112903763A (en) * | 2021-03-01 | 2021-06-04 | 中国石油大学(华东) | Ti3C2TxPreparation method of ammonia-based gas sensor and sensing application of ammonia-based gas sensor under assistance of light |
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Application publication date: 20211214 Assignee: GUANGXI AGLYCONE PLANT PRODUCTS Co.,Ltd. Assignor: GUILIN University OF TECHNOLOGY Contract record no.: X2023980044208 Denomination of invention: Modified cellulose nanocrystals with high thermal stability and their preparation method Granted publication date: 20220809 License type: Common License Record date: 20231025 |
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Application publication date: 20211214 Assignee: Guangxi Zaifa Energy Technology Co.,Ltd. Assignor: GUILIN University OF TECHNOLOGY Contract record no.: X2023980045075 Denomination of invention: Modified cellulose nanocrystals with high thermal stability and their preparation method Granted publication date: 20220809 License type: Common License Record date: 20231031 Application publication date: 20211214 Assignee: GUANGXI HEYANG ENERGY LTD. Assignor: GUILIN University OF TECHNOLOGY Contract record no.: X2023980045074 Denomination of invention: Modified cellulose nanocrystals with high thermal stability and their preparation method Granted publication date: 20220809 License type: Common License Record date: 20231031 Application publication date: 20211214 Assignee: Guangxi Wokang Medical Technology Co.,Ltd. Assignor: GUILIN University OF TECHNOLOGY Contract record no.: X2023980045070 Denomination of invention: Modified cellulose nanocrystals with high thermal stability and their preparation method Granted publication date: 20220809 License type: Common License Record date: 20231101 |
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Application publication date: 20211214 Assignee: Guangxi manjin Energy Saving Technology Co.,Ltd. Assignor: GUILIN University OF TECHNOLOGY Contract record no.: X2023980045248 Denomination of invention: Modified cellulose nanocrystals with high thermal stability and their preparation method Granted publication date: 20220809 License type: Common License Record date: 20231103 |