Cellulose nanocrystal and preparation method thereof based on oxidation reduction system

A cellulose and nanocrystal technology, applied in the field of nanomaterials and their preparation, can solve the problems of complex and harsh preparation process of Tempo reagent oxidation method, unsuitable for industrialized large-scale production, expensive Tempo reagent, etc., so as to save preparation cost and reduce The effect of preparing energy consumption and shortening the total time

Active Publication Date: 2018-08-07
QINGDAO UNIV OF SCI & TECH
View PDF5 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] In the prior art, the preparation of cellulose nanocrystals mostly adopts acid hydrolysis method, Tempo reagent oxidation method, etc.; among them, the yield of acid hydrolysis method is not high, and it is easy to cause acid pollution to the environment. Even if the acid recovery is re

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Cellulose nanocrystal and preparation method thereof based on oxidation reduction system
  • Cellulose nanocrystal and preparation method thereof based on oxidation reduction system
  • Cellulose nanocrystal and preparation method thereof based on oxidation reduction system

Examples

Experimental program
Comparison scheme
Effect test

Example Embodiment

[0047] Example 1

[0048] Soak 5g of pulp cellulose with 250mL of 4% sodium hydroxide solution and swell for 24h, then use a mixer to pulverize it into cotton wool, wash it with deionized water until the pH of the pulp cellulose is the same as that of deionized water, and then dry; in this step The sequence of swelling and crushing has no significant effect on the result. It can be swelled first and then crushed, or crushed and then swelled;

[0049] Disperse the pretreated cellulose raw material in 300mL deionized water, add 5g hydrogen peroxide and 1g ferrous sulfate, stir at 60°C for 1 hour, and use a cell pulverizer to perform mechanical defibrillation treatment at 49% power for 20 minutes, and then Continue to react at 60°C for 4 hours to stop the reaction, and the total reaction time is 5 hours. After the reaction, the cellulose hydrolysate was centrifuged at a speed of 8000 rpm / min for 10 minutes in a high-speed centrifuge, and then the precipitate was washed repeatedly wi...

Example Embodiment

[0052] Example 2

[0053] The oxidizing agent used is ammonium persulfate, the reducing agent used is sodium sulfite, and all other conditions (such as the type of raw material, the amount and the process flow, etc.) are the same as in Example 1, to obtain a stable suspension of cellulose nanocrystals. The average crystal length is about 283nm, the average diameter is 19nm, the yield is 50%, and the PDI is 0.3.

[0054] In addition, the oxidant ammonium persulfate in this embodiment can not only be matched with sodium sulfite, but also can be matched with reducing agents such as formic acid, succinic acid, ethanol, methanol, sodium hydride, sodium borohydride, etc., to obtain cellulose nanocrystals. The combination of sodium sulfite works best.

Example Embodiment

[0055] Example 3

[0056] The oxidizing agent used is sodium permanganate, the reducing agent used is formic acid, and all other conditions (such as the type of raw material, the amount and the process flow, etc.) are the same as in Example 1. A stable cellulose nanocrystal suspension is obtained. The cellulose obtained by measurement The average length of the nanocrystals is about 253nm, the average diameter is 18nm, the yield is 49%, and the PDI is 0.3.

[0057] In addition, the oxidant sodium permanganate in this embodiment can be matched not only with formic acid, but also with reducing agents such as oxalic acid, succinic acid, ferrous sulfate, methanol, sodium hydride, and sodium borohydride to obtain cellulose nanocrystals. , Among them, it has the best effect with formic acid.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Lengthaaaaaaaaaa
The average diameteraaaaaaaaaa
Average lengthaaaaaaaaaa
Login to view more

Abstract

The embodiment of the invention relates to a cellulose nanocrystal and a preparation method thereof based on an oxidation reduction system. The preparation method comprises the following steps: swelling and crushing cellulose raw materials, and washing; dispersing the pretreated cellulose raw materials into a water solution containing an oxidant and a reducing agent, so as to generate hydrolysis reaction; and carrying out post-treatment on the obtained hydrolysate, so as to obtain stably dispersed cellulose nanocrystal suspension liquid. According to the preparation method, the reducing agentand the oxidant are matched as an aid to participate in the hydrolysis reaction of cellulose, and the activation energy required by the oxidant for destroying an amorphous region is reduced by virtueof the interaction between the oxidant and the reducing agent in the reaction system, so that the reaction rate can be increased under relatively mild reaction conditions; and by adding the reducing agent, the preparation efficiency is improved to a certain degree, the use amount of the oxidant is reduced, the preparation energy consumption is reduced, and the preparation cost is saved.

Description

technical field [0001] The invention relates to the field of nanomaterials and their preparation, in particular to a cellulose nanocrystal and a preparation method thereof, and further relates to a cellulose nanocrystal and a preparation method thereof based on a redox system. Background technique [0002] Cellulose is the most abundant natural biological material in nature, and it is widely found in organisms such as green plants and marine animals. By removing the amorphous regions in the cellulose raw material, nanometer-sized cellulose nanocrystals can be obtained. Cellulose nanocrystals have the characteristics of low density, high strength, and high aspect ratio; they also have the advantages of high specific surface area, reactive surface, and high crystallinity. Huge application value. In addition, cellulose nanocrystals can be stably dispersed in the aqueous phase system, and can be grafted with appropriate monomers using water as the reaction medium, which cannot...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C08B15/02
CPCC08B15/02
Inventor 张建明周立娟段咏欣刘云霄王坤涛袁媛
Owner QINGDAO UNIV OF SCI & TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap