| abstract |
The invention relates to microporous articles made of polymeric materials. Such articles may, in one example, be battery separators for electrical storage batteries. In one embodiment, the article comprises a microporous flexible shape or sheet of a sulfur-free, cured polymeric material of a curable rubber an ethylene-propylene copolymer or mixtures of the curable rubber and ethylene-propylene copolymer. The article possesses an average pore size of less than 2 microns, a predetermined flexibility, and improved toughness, when compared to prior art sulfur cured articles. A continuous production of the cured rubber base material has been found to be especially advantageous. |