Preparation method of water-soluble 2'-hydroxylpropylchitosan

The invention discloses a preparation method of water-soluble 2'-hydroxylpropylchitosan which is prepared by using an isopropanol solution as a reaction system and epihydric alcohol as an etherifying agent through alkalizing, etherifying, neutralizing and purifying chitosan. The optimal reaction conditions are as follows: the amount of the chitosan is 2g, NaOH accounts for 30-40 percent, the amount of the epihydric alcohol is 15mL, the temperature is 60 DEG C and the reaction time is 10h. The color of the water-soluble 2'-hydroxylpropylchitosan obtained by adopting the method disclosed in the invention is white or light yellow, and the solubility is 6-12g/100mL of H2O. The invention has the advantages of ensuring that the reacted chitosan product is grafted with more hydrophilic hydroxyl groups by using the epihydric alcohol as the etherifying agent, and ensuring that the whole chitosan derivative has stronger hydrophily. The epihydric alcohol as a reactant has better hydrophily compared ...