Abstract:The dispersion effect of polyimide chopped fiber suspension was studied by changing the conductivity, pH, temperature and fiber concentration of the water-dispersed phase and optimizing by orthogonal test. The fiber sedimentation degree, absorbance and Zeta potential were used to characterize dispersion properties of polyimide fiber suspension under different water-dispersed phase conditions. The parameters of the best water-dispersed phase under the experimental conditions were determined, and the optimum fiber was selected. The concentration and properties of the polyimide fiber paper-based materials formed by the dispersed fibers under the optimal water-dispersed phase were discussed. The results show that under the experimental conditions, when the pH value of water is 6.0, the water temperature is 40 ℃, the fiber concentration is 4‰ and the conductivity of the aqueous solution is low, the dispersion performance of polyimide chopped fibers is better. The pore size distribution is more uniform. The tensile strength index of the paper-based material formed under this dispersion process is 35.9 N/mg, and the tear index is 40.1 mN·m2/g.