The invention discloses a preparation method of a
chitosan membrane. The method comprises the following steps of: dissolving
chitosan in 1-carboxymethyl-3-methyl
chlorine salt
ion liquid water solution of 1-5%, and enabling the
chitosan to completely dissolve so as to obtain a
stock solution of 1-5 wt% for preparing the
chitosan membrane; performing squeezing and filtering; performing standing and defoaming; performing rotary membrane
coating on a glass plate; performing
drying under constant temperature of 40 DEG C and constant
humidity of 50%; performing soaking in a
sodium hydroxide solution of 1-5% for 1-5h and stripping a membrane; cleaning the membrane in
distilled water till the pH is neutral; and
drying the cleaned membrane under the constant temperature of 40 DEG C and constant
humidity of 50% so as to obtain the
chitosan membrane. According to the
chitosan membrane, the thickness is 2.5-3.5 mu m, the
breaking strength is larger than or equal to 170MPa, the elongation at break is larger than 3.6%, and the initial modulus is larger than 3.3 GPa. The chitosan membrane can be used as
anticoagulant materials, bone repairing materials,
wound dressing materials, and the like.