POLYOLEFIN MULTI-LAYER POROUS MICROFILM AND MANUFACTURING METHOD THEREFOR

摘要

Disclosed is a polyolefin multi-layer porous microfilm and a manufacturing method therefor, the polyolefin multi-layer porous microfilm has an intermediate layer of polyethylene porous microfilm and two surface layers of porous microfilm both comprised of a polypropylene and a polyethylene having ultra-high molecular weight; the polyethylene of the intermediate layer has a molecular weight of 1x105 to 6x105; the polypropylene of the surface layer has a molecular weight of 1x105 to 1x106 and the polyethylene of the surface layer has a molecular weight of 5x105 to 5x106. In the preparation method, a raw auxiliary material for the intermediate layer and a raw auxiliary material for the surface layers are molten and mixed, the raw auxiliary materials of the intermediate and surface layers are dosed into a two-screw extruder, and then the same is subjected to multi-layer co-extrusion at a die, cooling and then drawing for film-forming, extracting and shaping, in order to obtain the product.