| 摘要 |
PROBLEM TO BE SOLVED: To provide a porous film composed of a high molecular weight polyolefin hard to extrusion-mold, and a manufacturing method thereof. SOLUTION: The porous polyolefin film is obtained using a non-reactive gas by melt-kneading by a twin-screw extruder a resin composition comprising a polyolefin having a viscosity-average molecular weight of at least 200,000 with a non-reactive gas, extruding the obtained polyolefin resin composition containing the non-reactive gas, cooling and solidifying the extruded polyolefin resin and stretching the cooled and solidified polyolefin resin. The manufacturing method of the porous polyolefin film is also provided. |
