Improving the wettability of polypropylene separators with maleic anhydride and corona discharge

Despite the variety of separators are commercially available, separators based on polyolefin (PP / PE) materials have received more attentions due to its outstanding properties such as low cost, easy processing, good mechanical properties and chemical stability. But, because of their hydrophobicity, their performance in wettability by electrolyte is poor. In this paper, the polypropylene separators were prepared by dry method (without the use of solvent) by stretching in one direction. The porosity obtained in this method was more than ۳۰% and the thickness of the films was about ۳۰ microns. To modify the wettability of the separators, blending with polypropylene-graft- maleic anhydride (PP-g-MA) anhydride has been used. The effect of corona discharge on surface modification of separators was studied, as well. The results showed that the addition of PP-g-MA as well as corona discharge significantly improved the wettability of polypropylene separators by electrolyte.