Abstract:The polypropylene (PP) fibers and polyethylene/polypropylene bicomponent sheathcore structure (i.e., ethylene propylene side by side, ES) fibers were used as raw materials, and good formation and high quality alkaline battery separators were prepared by using the wet-laid process. The internal structure of the separators was changed by adjusting the wet-laid process and the temperature as well pressure in hot pressing process, then using concentrated sulfuric acid as sulfonation agent to treat the battery separator in order to improve the hydrophilicity of the separators. The optimum process of preparing the polyolefin alkaline battery separators by using wet-laid process was explored. The results showed that the optimum hot pressing pressure and hot pressing temperature were 0.5 MPa and 135℃, respectively. Because the effective bonding between fibers of the handsheet was improved, the tensile strength of the handsheet was increased. When the dosage of PEO and PVA were 1.5% and 4% (on oven dry fibers), respectively, and the content of the ES fibers was 40%, the alkaline battery separators with well formation and high quality could be obtained.The sulfonic acid groups were successfully grafted on the battery separators after sulfonation treatment, which made the separators possessed strong hydrophilicity. The performance of resulted separators could meet the industrial requirement of an alkaline battery separator. |