Layered, water vapor permeable composite comprise at least one water vapor permeable film layer and at least one substrate layer, the water vapor permeable film (i) comprising at least one film forming polymer and at least one inert porous filler, (ii) having a water vapor transmission rate of at least 1000 g/m
2
/day, and (iii) activated. Representative film forming polymers include ethylene interpolymers, and representative fillers include silica glass beads. One exemplary method of activating the film is to subject it to sufficient pressure such that the glass beads are crushed within the film matrix.
层状透湿复合材料包括至少一层透湿薄膜层和至少一层基材层,透湿薄膜(i) 包括至少一种成膜聚合物和至少一种惰性多孔填料,(ii) 的
水蒸气透过率至少为 1000 g/m2
2
/天,(iii) 活化。代表性的成膜聚合物包括
乙烯间聚合物,代表性的填料包括
硅玻璃珠。活化薄膜的一种示例方法是将薄膜置于足够大的压力下,使
玻璃珠在薄膜基质中被压碎。