Method for homogeneously preparing different chitosan derivatives based on weak base system

Abstract

The invention discloses a method for homogeneously preparing different chitosan derivatives based on a weak base system. The method comprises the following steps: adding a chitosan raw material into an aqueous solution containing bicarbonate and urea, and directly performing stirring and dissolving to obtain an aqueous solution of chitosan; and adding a derivatization reagent into the chitosan solution, performing purifying and freeze-drying under specific reaction conditions to obtain the chitosan derivative. According to the preparation method disclosed by the invention, the chitosan derivatives can be homogeneously prepared by a one-pot method in a weak base system, the operation is simple and convenient, the reaction is controllable, the method is economical and environmentally friendly, and the multifunctional chitosan derivatives can be obtained by changing different derivatization reagents.

Description

technical field [0001] The invention designs a method for homogeneously preparing different chitosan derivatives based on a weak base system, and belongs to the field of polymer materials. Background technique [0002] Chitin is the second largest biologically derived resource after cellulose in nature, and chitosan is the deacetylation product of chitin, both of which have good biocompatibility and are easy to degrade in the natural environment, non-toxic and non-toxic. Harmless and pollution-free. With the continuous development of new chitosan solvents, new materials such as chitosan fibers, chitosan films, chitosan hydrogels, chitosan aerogels, and chitosan microspheres are widely used in separation, adsorption, and biomedical materials. , Flexible electronic devices and other fields have been widely developed, researched and applied, but the direct use of chitosan materials obtained through dissolution and regeneration is far from meeting the actual needs. In order to...

AI Technical Summary

Problems solved by technology

But chitosan is prone to the degradation of chitosan molecular chain in acidic aqueous solution, and under strong alkali system, dissolving needs to use a large amount of alkali and dissolving process needs to go through one or more freezing-thawing, and the solution obtained only in The properties are stable under low temperature conditions, the derivatization reaction can only be carried out under low temperature conditions, the reaction efficiency is low, the process consumes a lot of energy, and it is difficult to apply to the preparation of chitosan derivatives on a large scale

In the traditional alkali / urea system, the strong alkalinity of the solution is suitable for etherification reaction, but not for esterification reaction, which limits the types and choices of homogeneous preparation of chitosan derivatives