Method for measuring iodine elementary substance concentration of iodine polarizer

The invention provides a method for determining the concentration of elemental iodine of an iodine polarizer, which comprises the following steps of: preparing a series of iodine solutions with known KI concentration to obtain characteristic wavelength; preparing a series of iodine solutions with different iodine concentrations, obtaining the absorbance under the characteristic wavelength, establishing a mathematical model of the iodine elementary substance concentration in the impurity-free liquid and the absorbance of the characteristic wavelength, and obtaining a calculation model Y of the iodine elementary substance concentration in the impurity-free liquid; preparing a series of dyeing tank solutions with known concentrations, obtaining the absorbance of the characteristic wavelength of the impurity-containing liquid and the absorbance of the wavelength of the reaction characteristic absorption peak, and establishing a correction model Y1 of the absorbance of the characteristic wavelength of the impurity