| 摘要 |
A microporous polyolefin film made of a composition which comprises as essential ingredients (A) polyethylene having a viscosity−average molecular weight of 50,000 to 1,500,000 and (B) polypropylene having a viscosity−average molecular weight of 100,000 to 1,500,000 in such proportions that A+B is at least 80 wt.% based on the whole composition, A/(A+B) is from 51 to 90 wt.%, and B/(A+B) is from 10 to 49 wt.%, and which has a shutdown temperature lower than 140°C and has a continuous phase in which the polyethylene and polypropylene are intertwined with each other. |
