Method for preparing nanocrystal cellulose I by applying acid cation exchange resin

Abstract

The present invention relates to a method for preparing nanocrystal cellulose I by applying acid cation exchange resin, comprising the following steps of: adding fibers and the cation exchange resin in a solvent to obtain a suspension; stirring the suspension or carrying out ultrasonic or microwave radiation on the suspension; then further carrying out ultrasonic dispersion on the suspension and filtering the cation exchange resin to obtain a fiber suspension through separation; and further centrifugally purifying the fiber suspension in high speed to obtain the nanocrystal cellulose I. Because the acid cation exchange resin is used as an acid catalyst capable of decomposing H+ in the solution, the invention overcomes the defect of liquid acid reaction, and has the advantages of repeatable use, small equipment corrosion, little damage on the cellulose degradation, low environmental pollution and the like. Meanwhile, through combining with the special ultrasonic energy form and utilizing the energy, local high temperature, high pressure and cavatition generated by the ultrasonic, the method increases the surface area of the cellulose, promotes the permeation and diffusion of the solvent in the cellulose, and enhances the accessibility of the functional group of the cellulose.

Description

technical field [0001] The present invention relates to a method for preparing nanocrystalline cellulose, and more particularly relates to a method for preparing nanocrystalline cellulose I by using an acidic cation exchange resin. Background technique [0002] Cellulose is the most abundant, renewable and biodegradable natural polymer compound on the earth. How to fully and effectively utilize it has become a research hotspot at home and abroad. Cellulose can degrade amorphous cellulose through acid hydrolysis, enzyme treatment and mechanical methods, and retain crystalline cellulose to obtain nanocrystalline cellulose. Nanocrystalline cellulose has many excellent properties, such as high strength, high transparency, high crystallinity, high hydrophilicity, high modulus, ultra-fine structure and large specific surface area, etc., so nanocrystalline cellulose as a composite material It has good application prospects in enhancement phase, tissue engineering scaffold and filt...

AI Technical Summary

Problems solved by technology

[0003] At present, the preparation of nanocrystalline cellulose reported in the literature mainly adopts strong acid hydrolysis such as sulfuric acid, which is not easy to control the degree of cellulose degradation, and it is more corrosive to equipment, and the post-treatment will produce a large amount of acidic waste liquid, which has a great impact on the environment.