Chitosan membrane material prepared from chitosan solution with pH value of 6-8 and preparation method of chitosan membrane material

TL;DR: In this paper, a method for preparing a membrane material from a chitosan solution with a pH value of 6-8 was proposed, which was shown to be efficient, energy-saving, and environment-friendly.

Abstract: The invention discloses a method for preparing a membrane material from a chitosan solution with a pH value of 6-8. The method comprises the following steps: (1) preparing a dispersion liquid; (2) adding chitosan into the dispersion liquid, controlling the temperature to range from a freezing point to 35 DEG C, introducing carbon dioxide into the solution, stirring to dissolve the chitosan, stopping introduction of the carbon dioxide after the chitosan is completely dissolved, and defoaming to obtain a transparent chitosan solution with the pH value of 6-8; and (3) casting the chitosan solution to form a membrane, immersing the membrane into a coagulating bath to solidify and regenerate the membrane, carrying out uniaxial or biaxial orientation, washing and plasticizing, and drying to obtain the chitosan membrane material. Beneficial effects are that: the pH value of the dissolving method provided by the invention is 6-8, so that the degradation of a chitosan molecular chain can be effectively weakened; the dissolving process of the chitosan is efficient, energy-saving, and environment-friendly, the production efficiency is improved, and the production cost is reduced; and the prepared chitosan membrane does not have strong-acidity and strong-alkalinity substance residues, and the mechanical property of the chitosan membrane is good.