| 摘要 |
<p>Polyethylene films having desired water vapor transmission rates (WVTR) and methods of producing the same are provided. The methods include adherently superimposing at least one layer of a WVTR-controlling material to a base layer including a polyethylene and a cavitating agent, and subsequently biaxially orienting the composite polyethylene sheet to yield a film having the desired WVTR. The base layer has a porous microstructure and a WVTR substantially higher than the desired WVTR.</p> |
